How to Fly (Better)

How to Fly (Better) Entry #3 Climbs, Descents, and Level Fli

​Time for a Flight

So now you've hopefully had a chance to get familiar with an aircraft. Now we're going to try a quick flight from takeoff to landing. For this flight, I don't care where you go or if you actually land or how you handle the engine. We'll get to those things eventually. Here's the plan:

-Take off
-Climb
-Level off and get trimmed out
-Descend
-Level off and get trimmed out
-Return to base
-A few miles out, start your descent for landing
-Land at base

Now let's talk thought each phase of this flight.


Takeoff

You are at full power, landing gear are down, and you might have used some flaps. At full power starting from zero you are going to be accelerating, which will cause the nose to rise. Retracting landing gear and flaps will likely have the same effect, as well as reducing drag and thus aiding acceleration. To prevent the nose from going way high, you have probably unconsciously started to push the stick forward. So reduce the amount of pressure you have to put on the stick by applying some nose down elevator. You can allow the plane to keep climbing, but just use the trim to control it. The main thing at this point is to make sure that you are not climbing so steeply that your airspeed is decreasing. Now get your rudder and aileron trim sorted out to get the wings level and center the ball on the slip indicator.


Climb

You should already be climbing. You should be wings level, working to keep the ball centered, and the nose should be at a steady angle with airspeed either steady or still increasing. If you have trimmed well, all of this is happening without you touching the stick and rudder, or if you are, only the slightest corrections. Take note of what your airspeed is, what your vertical speed is, and how high your nose is above the horizon. Write these things down or remember them for later. Note that this data is only relevant if you are flying stable hands free.

Now, since we generally don't conduct steady climbs at full power, reduce power a little. I don't care how detailed you get if you adjust the prop as well or not or how much you reduce it. You can measure your reduction on the gauges in the cockpit, or just on the HUD readout. But decide what setting you will reduce to, and intentionally go to that setting. Remember it for later.

Now, without touching the stick or elevator trim, watch what happens. Your nose may drop a little with the power reduction, and then you will see airspeed start to drop, and as that happens, the nose will drop too. The power reduction has probably had an effect on aileron and rudder trim, so see to that to keep the wings level and ball centered, but leave elevator trim alone for now. As the nose continues to drop, you will eventually get to the point where airspeed stops decreasing, and the nose stops dropping. Speed will slowly start to build and you will see the nose start to rise again. Left on its own, the nose will gently bob up and down, with each one becoming more gentle than the last until the nose is basically stationary. It is worth noting that if you made a big power reduction, the swings will start larger and faster than if you had made a small one, but it will still stabilize eventually, but if it was too big of a reduction, you might not be climbing anymore.

Now that you are stable, climbing hands free, look at your airspeed and your vertical speed and compare them to what you saw before you reduced power. You should see that your vertical speed is lower, meaning you aren't climbing as fast, your nose will be somewhat less high above the horizon, but your airspeed should be very close to what it was before.


Level Flight

Now let's level out. Since we already know that engine power changes our rate of climb or descent, but our airspeed will settle out at the same speed, we can simply reduce power carefully until our vertical speed is zero. Once again, leave elevator and elevator trim alone, and adjust your engine power until your vertical speed reads zero. Don't forget to adjust your aileron and rudder trim. (Hopefully you are remembering to do this every time and are forming that habit, so from here on out I'm going to assume you are doing this every time you change what you are doing in the airplane and not mention it.) Note that we are just demonstrating a principle here and that this is not how you should level out from a climb normally. Once stabilized, you should now be level and at the same airspeed as before.


Acceleration

So, if engine power is controlling our climb rate, but not making us any faster (once we're restabilized) how do we accelerate in level flight? Well, go ahead and increase throttle, but this time, as you accelerate, don't allow the nose to rise. Apply some nose down elevator to keep it level and then use elevator trim to reduce how much you have to hold the stick forward until you can completely let go and the aircraft remain in level flight. Now we should be level, stable, and flying faster than we were before. Note that this result required us to use engine power AND elevator/elevator trim.


Decent

Time to try a descent. Based on what we've tried already, you should be able to tell that a small power reduction is going to result in a gentle descent and that returning power to it's previous setting will result in level flight, so let's try something new. This time, we will leave engine power alone and see what happens when you only adjust trim. So, apply a bit of nose down elevator trim until the nose pitches down slightly. Immediately we see airspeed start to increase and our vertical speed indicator is showing a descent. Now leave the elevator trim alone and watch the results. The airspeed increases, and as it does, the rate of descent decreases. It might even turn into a climb temporarily, but eventually it should settle out with you in a descent at a somewhat higher airspeed, but your descent rate will be much less than when you first applied the nose down trim at the lower airspeed. If you are flying a particularly heavy and/or underpowered aircraft, you may actually find that you have maintained level flight at a higher airspeed just by applying some nose down elevator trim. At a previous job, I encountered this regularly carrying tourists over the Grand Canyon on hot summer days. The performance of a Cessna 207 at those temperatures and at that altitude is rather pitiful, even with a turbocharged engine, and flying technique could make a huge difference in what the airplane would give you.


Level Flight

Anyways, let's stop the descent the same way you started it, by applying some elevator trim in the opposite direction. If you are flying the SJ Spitfire for these flights, you may have noticed the handy elevator trim indicator on the instrument panel. If you paid attention to where it was last time you were flying level, you can go back to that same setting and expect to once again be flying more or less level. Alternatively, you can use the Z key info readout and see your elevator trim setting there.

Fly home and land. I'm not going to talk about landing procedure and technique now, but see if you can apply some of what you have learned on this flight to your landing. Hopefully, you'll find yourself having an easier time of it.


Important Principles

Here are the key principles to remember from this flight.

1. Power is not about forward speed so much as it is about vertical speed. Adjusting power on its own will only make you climb or descend. It can certainly allow you to go faster or slower, but ONLY when used alongside appropriate adjustments of elevator, or elevator trim. So when you adjust engine power, stop expecting an airspeed change and start expecting an altitude change instead. If what you want is an airspeed change, remember you will have to use elevator trim too.

2. Elevator trim changes both forward speed and vertical speed. However, it makes a less effective control of vertical speed in normal maneuvers because vertical speed is so dependant on engine power (note, this is not as applicable in combat maneuvers). It has its most immediate effect on airspeed.

3. The aircraft flies predictability! For most people, it is mainly a matter of learning to expect the right things. If you're like I was in the beginning, you assume throttle is about airspeed and the elevator makes you go up and down. When you find out the reverse is true, you start thinking and flying differently, and you find you can fly with greater precision with much less effort.

4. What is predictable is measurable. This is why we have instruments. You can set a power setting for your engine, and a trim setting for your elevator, and know that the combination will result in a specific airspeed and a specific vertical speed.

5. What is understood, can be predicted. What is predicted can be measured. What is measured can be mastered. Taking all of the other points together, you can go to known settings for what you want to do, be that a climb or decent at a certain airspeed and/or vertical speed, or level flight at any speed within your aircraft's performance envelope, and it will just happen. You don't have to manhandle the plane to make it do what you want (and if you try, you'll be disappointed.) You just have to tell it what you want in language it understands. The airplane doesn't "speak" airspeed and vertical speed, but it certainly understands engine power and elevator input. Know the settings you want, and the airplane will reliably give you the results you want. This is also how the airplane tells you when something is wrong. If you give it the same inputs you always have, and are getting a different result, you know you have a problem to diagnose.
 
So, I've put three of these out and I'm curious how it's being received. Are they helpful? Do they make sense? Are there questions about any of it? Do you wake up early every morning in hopes that this will be the day the next entry is finally posted? Ok, maybe not. There doesn't necessarily have to be discussion on any of the entries if nobody wants to, but if it isn't being helpful and I'm talking to an empty room, I'll find something else to do on my lunch breaks. If it's worthwhile, I'm perfectly happy to keep going.
 
Well I am paying attention and, at the end I hope to put them all together as a document for the knowledge base. Good info fro those hoping to fly more realistically. Frankly, I wonder how much my trimming issues are due to my X56 input 'wiggles' and even keyboard feed, or if it has to do with the CFS3 model. Even with 2-4 engine aircraft, which I mainly use, I have rudder trim problems, always it seems to veer starboard. Could be my setup??
 
I had an X52 and eventually replaced it after the sensors got too jittery. I think that's a weakness with the Saitek sticks. I went with a Logitech 3D Pro which was much smoother, but I still kept my X52 throttle. A good joystick definitely helps trimming! It simply isn't possible to do it well if your sensors are jumpy.

The gold standard would be to use a higher end joystick with a Halls sensor, which are contactless and don't wear out.

A very light touch with the trim is helpful too. In a real aircraft, my adjustments to trim when I'm fine tuning (on an aircraft with manual trim) are nearly imperceptible. Electric trim on aircraft has about the same precision as you can achieve in CFS3, which is certainly good enough, but not quite as perfect as what a manual system can do.

I suspect your veering to starboard issue is something with your setup. It could be a calibration thing, or if your joystick or rudder has been around for a while, the sensors might be wearing out. I doubt it's an issue with CFS3.
 
I have been keeping up with these posts and intend to try them out. Haven't been able to fly the last couple of weeks as I rebuilt/upgraded my computer and reloaded most of it from scratch. Did keep the drive with CFS3 programs and saved some user folders.

I had always trimmed out the yaw with ailerons and maybe some elevator, not rudder. I was thinking the rudder trim put more drag on the plane. I guess I was wrong.

Also always wondered, if I trim out at reduced power how it might affect full power combat performance.

Keep them coming!

Bob
 
This is really great. Learning how to fly real challenging aircraft such as the F-16 in Falcon BMS. Aircraft take much more attention in modern jet fighter/bombers. Falcon BMS has to be the most challenging air combat sim i've ever played. Love flying the WW I and WW II aircraft ,but fighter tactics in modern aircraft have changed to some degree. Dogfighting rules haven't changed that much other than beyond visual range tactics and defense. Thanks for all the information !
 
mcbob said:
I have been keeping up with these posts and intend to try them out. Haven't been able to fly the last couple of weeks as I rebuilt/upgraded my computer and reloaded most of it from scratch. Did keep the drive with CFS3 programs and saved some user folders.

I had always trimmed out the yaw with ailerons and maybe some elevator, not rudder. I was thinking the rudder trim put more drag on the plane. I guess I was wrong.

Also always wondered, if I trim out at reduced power how it might affect full power combat performance.

Keep them coming!

Bob
Click to expand...

The relationship between trim and drag is going to vary from aircraft to aircraft, but it will generally be pretty negligible. Trimming causes the control surfaces to deflect, which of course creates some drag, but to fly the airplane, even straight and level, is still going to require the exact same control surface deflection to get the same result, whether you are holding the pressure yourself or using trim to do it for you. Take a look at a picture of a Spitfire in level flight, and you will notice the elevator is always deflected slightly down. That certainly causes more drag than if it was in the streamlined position, but if you streamline the elevator with the horizontal stabilizer, you will find yourself in a significant climb. Obviously you can't go as fast in a climb as you can in level flight, so the Spitfire's top speed is reached with the elevator deflected slightly downward. You can experiment with this in the SJ Spitfire Mk.V, which replicates this facet of the design. Had the Spitfire been designed slightly differently, such that the elevator was streamlined in level flight, it might have been faster, but this "design flaw" also contributed to its wonderful lightness on the elevator, so just like any aircraft design, it's a compromise to get the desired results. When I worked building and test flying for a home-built aircraft company, I would customize the control surface rigging to meet the desires of the customer. Rigging the ailerons so they drooped slightly below the wing when in the neutral position, gave the aircraft a lower stall speed, allowing for lower landing speeds and stopping distances, allowing shorter airstrips to be used. But this came at a cost in top speed since the drooped ailerons caused more drag. If they wanted the best top speed and efficiency they could get, I rigged the ailerons streamlined. Some wanted a compromise between the two. In most categories of aircraft you don't have that kind of flexibility, and the design is what it is, but hopefully those examples demonstrate some of how having control surfaces streamlined at the neutral position is not always best, and is actually one of the design features of the aircraft.

Now, you might say that a trim tab being deflected to deflect the control surface creates more drag than if the pilot kept the trim tab streamlined and deflected the control surface manually to achieve the desired results. Sure, that's true, but we aren't talking about huge differences. And as the aircraft accelerates, it is generally going to take progressively less trim deflection to achieve the same results than at a slower speed. So the faster you go, the less effect the trim tab is going to have on drag. Now you have to balance that with your own ability to keep the aircraft stable without the aid of a trim tab. Bobbing up and down as you try to hold it perfectly steady is going to hurt your top speed way more than the little bit of drag the trim tab is adding. There is no way you are going to hold the aircraft as steady by hand as the trim tab will if you use it with precision.

Looking at your question about trimming at reduced power and then going to full power - since pushing the throttle forward to increase engine power is a change in the configuration of the aircraft, your trim needs are going to change. Rudder and aileron trim will need to compensate for the increased torque effects (assuming a propeller-driven aircraft) and as you accelerate, your elevator trim needs are going to change. Speaking of just the elevator, one of three things is going to happen:
1. You don't move the elevator or the trim, and you begin to climb, eventually settling out at the same airspeed as before, but now climbing instead of flying level.
2. You do your best to hold the plane level by pushing the stick forward, having to push harder and harder as you accelerate.
3. You gradually increase nose down elevator trim to keep the aircraft level as you accelerate.

So it's a question of what you want to do and how hard you want to have to work. The pilot who uses trim effectively is going to outperform the pilot who does not.

One last note on trim, specifically rudder trim, yaw, and drag. Flying with the ball centered is called flying coordinated, and it means the aircraft is aligned with its direction of flight. As the ball moves away from center, this indicates that the aircraft is becoming increasingly less aligned with its direction of flight, meaning more and more of the side of the aircraft is being presented to the oncoming wind instead of just the forward facing surfaces. This creates a LOT of drag since you are basically trying to push the airplane through the air partly sideways. You are going to have less drag and go faster if you fly coordinated with the ball centered than if you don't, no matter what you have to do with the controls to make it happen. Rudder and rudder trim are the go-to means of keeping the ball centered.

Hope that helps answer those questions. Great questions, by the way.
 
gecko said:
[STRIKE]And as the aircraft accelerates, it is generally going to take progressively less trim deflection to achieve the same results than at a slower speed. So the faster you go, the less effect the trim tab is going to have on drag.[/STRIKE]
Click to expand...

I need to correct this point. It was late and I must have been more tired than I thought. The faster you go, the more nose-down trim you are going to have to apply, so the trim tab will be deflected more, not less, and the drag created by it will also be more, not less. However, I'd still say it isn't going to affect top speed all that much, and that any speed increase from not using trim and holding the controls manually is theoretical, and in practice you aren't going be able to hold the aircraft as steady as the trim tab will unless that's all you're focused on. This just isn't practical unless you're a test pilot trying to find the absolute top speed of the aircraft.
 
There will be. I have the start of one, but haven't had much time to write it. I'll be using the SJ Spitfire Mk.V to explain flying by known configurations for different phases of flight and transitioning between those configurations, as well as eyes-outside flying. Mastering those skills will set you up for working on good, safe landings in the next part. After that I'll probably do a bit on taxi and takeoff. After that, there are a lot of other places we could take it, and I'm open to suggestions for what people want to learn about.
 
Landings for me are the most difficult. How to loose altitude and still keep the nose up/level rather than down is really hard.
 
How to Fly (Better) Entry #4 - Flaps

Since the next post may be longer in coming since it is a bit more involved, I thought I'd do a quick one that I think will be helpful before trying to tackle it. We haven't talked all that much about flaps, what they do, when to use them, etc.

There are various types of flaps, and we have a number of them represented in our CFS3 aircraft. Common to nearly all of them are four things.
1. Lowering them increases lift.
2. Lowering them reduces stall speed.
3. Lowering them increases drag.
4. Lowering them causes the aircraft to pitch down somewhat.

An exception to that last point is the Me 163. Its flaps are positioned more forward on the wing, at a point where they do not cause the aircraft to pitch either up or down.

Hopefully from the above and what we've talked about in previous posts, you can deduce that using flaps will have a big effect on airspeed control, and vertical speed control. We can also deduce that, if used appropriately, flaps can:

1. Reduce turn radius.
2. Reduce takeoff and landing distances.
3. Increase climb rate and or angle.


Uses of Flaps:

Landing: Using flaps for landing is the primary purpose for flaps on almost any aircraft. Because of their effect on lift, drag, and stall speed, they allow controllable flight at much lower airspeeds. When you are trying to return to earth in a controlled fashion and in one piece, slower is better. A slower landing speed also reduces the distance it takes to stop.


Takeoff: Most aircraft at least have the option to use flaps for takeoff, which reduces takeoff distance. Full flaps are seldom used, since the drag penalty tends to slow the acceleration enough that it overrides the lift benefit. Typically, some intermediate flap setting will be designated as the takeoff setting. In the Fw 190, you literally press a button for landing setting, takeoff setting, and flaps up. Most others you just remember what the setting is in degrees and set that.


Deceleration: Flaps can be used to decelerate. This is commonly done in the traffic pattern as you prepare for landing. Typically, flaps will gradually be lowered in increments prior to final approach, either while maintaining level flight or while descending. This culminates in reaching final approach speed with the flaps fully extended.


Terrain/Mountain Flying: When your options are constrained by terrain around you, flaps can reduce the area required to maneuver, both vertically and horizontally. In the vertical, lowing flaps to an intermediate setting increases your climb angle, meaning you gain more height for every foot forward you fly. If you find yourself boxed in by terrain slowing down and popping in some flaps just might make the difference. Horizontally, it reduces your turn radius. It does this by slowing you down (less distance forward covered per degree of turn) and once in a steep bank, a large portion of that extra lift produced by the flaps is directed horizontally, and pulls you through the turn. The results are dramatic, and can allow safe flight in surprisingly tight terrain. In a previous job I did a lot of flying in valleys and canyons, and used flaps extensively to increase my safety margin in confined areas. As with takeoff, generally full flaps are not used for this.

An example of this is a portion of a tour route I used to fly in Arizona where a climbing turn had to be executed in a confined bowl with vertical canyon walls. The prevailing winds often created strong downdrafts capable of shoving an unprepared pilot right down into the canyon on one side, and strong updrafts on the other, where the wind hit the opposite wall and shot upward. I would hug the canyon wall at close to the airspeed limit for 10 degrees of flaps. As the oncoming wall of the bowl filled my windscreen, I would start to pick up the updraft, put in my 10 degrees of flaps, bank away from the wall and start climbing. The extra speed is not desirable in a turn in a confined space, but it can be converted to altitude very quickly, which was extremely desirable to combat the downdraft I was about to fly into. The flaps boost the deceleration, the climb, and cut the turn radius almost in half all at once, keeping me well clear of terrain, with a good enough climb rate to fight the downdraft. If the downdraft was exceptional that day, I would also be slow enough at this point to apply another 10 degrees of flaps to overcome it.

Go take a flight in the Alps sometime and try it out turns in a narrow valley. It can be a lot of fun.


Combat: Some aircraft like the P-51 and P-38 are equipped with combat flaps. These are just their regular landing flaps, but the smaller settings are able to be deployed at very high speeds without damage, and if I'm not mistaken, a relatively small drag penalty. In my above example, I had to make sure I didn't start my turn at too high an airspeed, or I would damage my flaps. No such problem with these aircraft. All of the advantages described above can be used to keep yourself out of the enemy's sights, or bring him into yours. But be careful, the flaps and all that tight turning will bleed off your all-important energy, putting you at the mercy of your opponent if not used with discretion. You can find lots of examples in after action reports about the use of flaps at opportune moments in a dogfight on planes that had this capability.


Emergency Descents: If you find yourself in a situation where you need to get down to the ground immediately, to avoid attack or some other emergency, and you aren't in a fighters that is stressed to take the speed and g-loads of a vertical dive and pull out, deploying everything that creates drag on your aircraft (thus including flaps), and pulling the power to idle will give you a rapid descent without ripping the wings off. It's a handy thing to have in your back pocket when you need it.


One very important thing to note with all of this is that flaps have airspeed limitations. If you lower the flaps at too high of an airspeed, they can be damaged or even ripped off. CFS3 does model this, including asymmetric damage to your flaps, which results in total loss of control. Usually there will be more than one limitation, associated with different degrees of flap extension. Each type of aircraft will have its own limitations, so make sure you know what they are on the one you are flying.


Flaps and Trim Changes:

Supposing you are in stable, level flight, lowering the flaps will initially result in a lowered pitch attitude, a climb, and reducing airspeed. Depending on the aircraft, your power setting, and how much you lowered the flaps, once the airspeed has stabilized, you may still be climbing, you might be level, or you could be descending. In any case you WILL be slower. If you are stable climbing or descending, you will see an initial increase in climb rate, or decrease in descent rate, respectively.

If you have flaps down, and raise them, you will see the reverse of all these effects.

To decelerate by lowering flaps but still maintaining level flight, you initially will have to use a lot of forward stick pressure to combat the sudden increase in lift. Note - always make sure you are under the airspeed limitation for the amount of flaps you are extending before extending them. You may want to trim out the pressure with elevator trim, but your initial response needs to be with the elevator, since trim will not respond fast enough. As the aircraft slows down, the pressure or trim required to hold it level will reduce, and eventually reverse as you start to pull back on the stick to keep the aircraft from descending. You may further have to increase engine power to keep from slowing too much and stalling. To accelerate by raising the flaps again, the reverse will be true - first having to pull more elevator due to the loss of lift, and then reducing it as speed increases. The caution here is to make sure you are above the stall speed for whatever reduced flap setting you are selecting. The stall speed will increase as lift decreases as the flaps retract. If you are below it when you do, you will stall. Additionally, if you have intermediate flap setting airspeed limitations, make sure you don't blow right through them as you accelerate before actually raising the flaps above that limitation.

Suffice it to say, a lot happens when you change your flaps setting. The key is to anticipate the changes, before you do it, and correct accordingly.


That's all for now on flaps. I just thought it would be good to get familiar with them before moving on. Try experimenting with the effect of flaps when raising and lowering them, while leaving engine power and trim alone, and then try some decelerations and accelerations using flaps while maintaining the same altitude. If you want, you can also experiment with turn radius with and without flaps extended, and try an emergency descent in a bomber, or experiment with using them in a dogfight (if your aircraft has combat flaps). If you want to really go the extra mile, see if you can put together everything from this and the previous posts, and try to maintain a steady rate of descent and a constant airspeed while changing flap settings (hint: you'll be changing engine power and trim a lot).

Have fun!
 
How to Fly (Better) Entry #5 - Configurations

In this part, we are going to put together what we have covered in the previous sections into a flight. On previous flights, we were experimenting with the effects of different controls or changes to aircraft configuration. On this flight, we will practice flying in a very practical, operational way. We will focus on knowing the exact configuration we want to put the aircraft in for different phases of flight, and transitioning between those configurations. The idea is to take the guesswork out of getting the aircraft to do what you want it to do. This will come very much in handy for setting yourself up for success with tasks involving a bit more precision, such as landing.

For this flight, I am going to be using the SJ Spitfire Mk.VA and the Real Systems Module. It has some idiosyncrasies that I think make it good for giving you an idea of the kinds of considerations you need to keep in mind when working through aircraft configurations. You can choose to follow along step by step in the Spitfire, and I'll walk you through it, or you can try to apply the principles to a different aircraft.

I am also going to introduce eyes-outside flying as part of configuring the aircraft for different phases of flight. Basically, I want you to forget that the artificial horizon in your cockpit exists. The name of the gauge gives away the purpose of this. It is an artificial horizon. It is a tiny, scaled down, less precise version of the real horizon and serves as a backup for when you can't see the actual horizon. We use the horizon (and in instrument conditions, the artificial horizon) for more than just general orientation of which way is up and which way is down. It allows us to set precise pitch and bank attitudes to achieve desired outcomes. And to be clear, when I talk about pitch, I am talking the aircraft's pitch attitude as referenced by the position of the nose relative to the horizon. I am not talking about propeller pitch. Setting a specific pitch attitude is just as much a part of flying as are engine power settings and trim settings. It can be done just as precisely, and, once you are really at home in your aircraft, nearly unconsciously. Much like how you tend to have the lane stripe on the road disappear from view under a specific part of your car's hood (or bonnet, if you're driving on the wrong side of the road :biggrin-new:), you will have the horizon intersect a specific part of your cockpit's framing. This spot will be different of course depending on what you're trying to do. A max rate climb will look different from a cruise climb, level flight, a 45-degree bank, etc. But, much like learning to drive where you have to pay a lot of attention to where that spot is to stay in your lane at first, eventually you learn to put it in the right place without thinking.

A note on power changes. There is a right way and a wrong way to do this. The wrong way can literally melt your engine in very short order. For most of our aircraft, you have a throttle lever, an RPM lever, and a mixture lever. When increasing power, always move the mixture lever to the rich position first, followed by the RPM lever, and finally the throttle. The reason being, you don't want to add all that power before the engine has the fuel and RPM it needs to avoid detonation. Likewise, when reducing power, you use the reverse order, again to avoid putting the prop and mixture controls in a setting only appropriate for lower power when the throttle is still at a high setting. Most CFS3 aircraft don't have these consequences modeled, but the Spitfire will bite you hard for it.

A note on the configuration specifics. These are intended to get you as close as I can to being able to fall into the desired phase of flight efficiently and without hunting around too much for good settings. Consider them good known settings to go for initially, and be prepared to fine tune them to get the desired results. Different flight conditions, particularly altitude, along with fuel and weapons load, can cause some variance in parameters. There are defining performance benchmarks for each phase of flight and all other settings are tweaked to achieve precision in those benchmarks. I have marked them in bold.

These are my own notes for how I fly the aircraft. They are based first and foremost on the original pilots notes for the aircraft, and also from cockpit videos where I can see what actual Spitfire pilots are doing. I don't make any claims that a real Spitfire pilot would look at these and say everything is right. It is just one way to do it and it works well in CFS3.

There is a lot of material here - break it up into more manageable chunks if need be. But keep in mind that it is not just the configurations themselves we are working on, but also transitioning between them, so don't isolate them from each other.


Take-off

So, first thing first - takeoff. I am not going to go into takeoff technique right now, but I will give you the configuration parameters. Here our main concerns are to get off the ground safely, and accelerate to keep the radiator temperature within limits. The liquid-cooled engine is still cooled by air passing through the radiator. If we want to keep the engine cool, we need airspeed so that there is enough air flow through the radiator.

Mixture: Auto-Normal (lever fully back)
Propeller: Max (3,000) RPM (lever fully forward)
Throttle: Max (+12.5 lbs boost at sea level)
Flaps: Up
Elevator Trim: 1 Division Nose Down on the elevator trim indicator
Rudder Trim: Fully starboard
Radiator Shutter: Fully Open
Undercarriage: Up (shortly after liftoff)
Pitch: Bottom of gunsight glass level with the horizon
Airspeed: Rapidly accelerating to at least 140 mph
Rate of Climb: Less than 1,000 feet per minute
Radiator Temperature: Less than 135 C


Climb

Now that we're off the ground and accelerating, the next thing to do is to set up a good, sustainable climb. What kind of climb we perform depends on the mission. If we have inbound bandits at Angels One-Five, we need to gain altitude as quickly as possible to be in position to intercept with an altitude advantage. If we are off on a fighter sweep over occupied France, fuel efficiency is more important, so we might consider a more leisurely cruise climb.

Combat Climb

Not much changes from takeoff configuration, but now our attention shifts to maintaining the optimum airspeed for climb. In the Spitfire Mk.V, the best rate of climb airspeed is 170 mph below 10,000ft. To transition to a combat climb from takeoff configuration, all you need to do is reduce engine revs to 2,850 RPM using the RPM control once you are higher than 2,500 feet above sea level and set your pitch to give you an airspeed of 170 mph. As you climb, you may be able to progressively close the radiator shutter if temperatures are running in the 80-90 C range. This reduces drag and gives you better performance. You will need to adjust rudder trim whenever you change the radiator shutter position. Once everything has settled in climbing at 170 mph and trimmed hands free, make a note (actually write it down) of where the horizon is relative to your cockpit. I have included in the configuration specifics an approximate pitch attitude you can expect to work, but you will need to create a clear mental picture of exactly the pitch attitude that works.

Mixture: Auto-Normal (lever fully back)
Propeller: 2,850 RPM
Throttle: Max
Flaps: Up
Elevator Trim: Slightly less than 1 Division Nose Up
Rudder Trim: As required
Radiator Shutter: Fully Open
Undercarriage: Up
Pitch: Lower front corner of windscreen quarter windows level with the horizon
Airspeed: 170 mph
Expected Rate of Climb: ~2,500-3,000 feet per minute - varies with altitude
Expected Radiator Temperature: - varies with altitude

Cruise Climb

As mentioned earlier, cruise climb is a more fuel-efficient way to get yourself to altitude. Here we climb at a reduced power setting (max continuous power), and instead of flying by an airspeed and letting the climb rate be what it will be, we set a rate of climb, and let the airspeed settle in where it will. Whether coming down from takeoff configuration or a combat climb, the process is the same. Reduce throttle first, followed by RPM. Pitch for the desired climb rate (let's just say 1,000 feet per minute in this case), and trim for hands free flight. As with combat climb, make a note of where the horizon is. Also, to an even greater extent than combat climb, you may be able to get the radiator shutter closed somewhat while still maintaining good temperatures.

Mixture: Auto-Normal (lever fully back)
Propeller: 2,650 RPM
Throttle: +7 lbs
Flaps: Up
Elevator Trim: Neutral or slightly nose down
Rudder Trim: As required
Radiator Shutter: Fully Open (can probably eventually close it)
Undercarriage: Up
Pitch:Bottom of gunsight glass level with the horizon
Expected Airspeed: ~225 mph - varies with altitude
Rate of Climb: 1,000 feet per minute
Expected Radiator Temperature: 75-85 C - varies with altitude


Cruise

When it comes to level cruise, there are many possible configurations appropriate for different operational needs. We will only look at a "normal" cruise and a combat cruise here, but just be aware that there are different settings for maximum range, maximum endurance, etc.

Normal Cruise

We're going to first look at a general purpose normal cruise, and also practice a level out from climb. The first part of this is timing. If you want to level out at a specific altitude, you will want to lead your level out altitude and start leveling out prior to reaching the desired altitude. A good rule of thumb is to lead it by 1/10th of your rate of climb. So leveling out from a 1,500 foot per minute climb, you will want to start reducing pitch to a level flight attitude 150 feet before your target altitude. Pitch until you are holding altitude with no climb or descent rate showing, and start trimming to hold it. Allow yourself to accelerate a bit before reducing power. Reduce throttle first, then RPM, and for this configuration, you will also set the mixture to Auto-Weak. Trim for hands free flight, and reduce your radiator shutter setting to the greatest extent possible. Note the position of the horizon.

Mixture: Auto-Weak (lever fully forward)
Propeller: 2,400 RPM
Throttle: +2 lbs
Flaps: Up
Elevator Trim: Neutral
Rudder Trim: As required
Radiator Shutter: As required
Undercarriage: Up
Pitch:Top of cowl at horizon
Expected Airspeed: varies with altitude
Rate of Climb: 0 feet per minute
Expected Radiator Temperature: 70-80 C - varies with altitude

Turns

Obviously, if we are going to navigate anywhere, we will need to make some turns. But since this disturbs the equilibrium we are trying to maintain, adjustments need to be made. Let's enter a 30-degree banking turn to the left. You will achieve and maintain the bank angle with ailerons, but there is more you have to do. Keep an eye on the horizon and verify with your vertical speed indicator, because if left to its own devices, your nose is going to drop somewhat. Counteract this by pulling back on the stick to maintain the horizon at the correct level and cross check your airspeed to ensure you aren't accelerating or decelerating. Once you have the right picture in your head, you can fly very accurately without referencing the gauge. A left turn will require left rudder to keep yourself coordinated. Also, this whole process causes you to lose altitude. To maintain it, you need to increase engine power. I have found that adding about 1 lb of boost on the boost gauge is a good ballpark guess for 30-degree banks on the Spitfire. Steeper banks will require more power to be added. This also holds true in climbs and descents to maintain a steady rate of climb or descent.

Combat Cruise

In a combat zone where you may get bounced at any moment, it is wise to keep your speed up. You can't sustain full combat power for long, but a high-power combat cruise is the next best thing. So we're going to practice increasing power here. First, move the mixture lever to Auto-Normal, then increase the RPM, and lastly increase the throttle. You will likely have to open the radiator shutter somewhat to maintain cool engine temperatures. Also remember that even though you are still maintaining level flight, since we are accelerating, you will still have to apply some nose-down trim to keep from climbing. As before, note the position of the horizon. Also note that due to our higher airspeed, our nose is somewhat lower than in normal cruise, but we are still maintaining altitude. This is also a good time to remember to take the gun safety off and turn on the gunsight.

Mixture: Auto-Normal (lever fully back)
Propeller: 2,650 RPM
Throttle: +7 lbs
Flaps: Up
Elevator Trim:1/2 Division Nose Down
Rudder Trim: As required
Radiator Shutter: As required
Undercarriage: Up
Pitch:Top of gunsight frame slightly above horizon
Expected Airspeed: varies with altitude
Rate of Climb: 0 feet per minute
Expected Radiator Temperature: 80-90 C - varies with altitude


Descent

Time to head home and start a descent. We could get into how to determine when to descend, but I think I'll save that for if we ever get into navigation. Here I'll just cover how to do it. We are basically going back to a normal cruise setting, but maintaining a steady descent instead of level flight. Since it is a power reduction, we will reduce throttle first, then RPM. We are going to leave the mixture control in the Auto-Normal position. The reason for this is that if descending at a reduced power setting from high altitude, as you descend, the boost pressure supplied by the set throttle position is going to increase. It is very easy not to notice this and end up with a higher boost pressure than is safe for using Auto-Weak mixture. For navigational planning, it is best to target a set rate of descent instead of a set airspeed. In this case we will use 2,000 feet per minute. Engine over-cooling is a concern in this phase of flight, since we have a lower power setting and thus aren't generating as much heat, but the descent gives us a lot of airspeed, and thus much greater cooling than normal. So we will close the radiator. As we push the aircraft into the descent, as airspeed builds up, the amount of nose down trim will need to be steadily increased until airspeed stabilizes. Always remember, you aren't done trimming until your speed is stable. As always, note the position of the horizon.

Mixture: Auto-Normal (lever fully back)
Propeller: 2,400 RPM
Throttle: +2 lbs
Flaps: Up
Elevator Trim: 3/4 Division Nose Down
Rudder Trim: As required
Radiator Shutter: Streamlined (lever positioned adjacent to the red triangle on the map box)
Undercarriage: Up
Pitch: 1/4 of the gunsight glass above the horizon
Expected Airspeed:~290 mph - varies with altitude
Rate of Descent: 2,000 feet per minute
Expected Radiator Temperature: ~75-85 C - varies with altitude


Landing Pattern

When we level out from our descent to prepare for landing, we are going to want to level out at about 1,000 ft above ground level. CFS3 doesn't do us any favors here since the elevation of the different airfields isn't readily accessible and our altimeters read altitude above sea level. It might be best to practice at an airfield that is basically at sea level to give you a rough feel for what 1,000 ft looks like. And, as with the climb, we want to lead the level off by 10% of the descent rate. Since we were doing 2,000 feet per minute in our descent, we'll start the level off 200 feet higher than our target altitude. The main task here is to maintain that altitude while slowing to a speed from which we can begin to configure for landing. In all the other phases of flight, we chose either a rate of climb/descent or an airspeed to target, but from here until we touch down, we will be targeting a specific airspeed and a specific rate of descent. But by now, you should be able to tell that in each of our configurations so far, there was a corresponding rate of climb or descent to any airspeed we tried to hold, and an airspeed that corresponded to any rate of climb or descent. The key was a consistent configuration, and that is all we are doing here. So as we level out we want to reduce power to maintain an airspeed of 140 mph. Undercarriage and flaps can be extended below 160 mph, so this speed gives us some margin so we don't accidentally damage them during a moment of inattention. As we slow down, radiator temperatures will start to increase due to less air flow through the radiator. They are about to increase a lot more as we slow further and encounter an interesting Spitfire quirk when we lower the flaps and undercarriage. With the undercarriage down, the radiator inlet is partially blocked, and when the flaps are down, the outflow from the radiator is seriously obstructed. Combined with low airspeeds, this causes radiator temperature to climb quickly. It is a good idea to get ahead of this and open the radiator fully and re-trim the rudder before starting your approach. Here I also need to mention something about how your constant-speed propeller works. So far we have been setting our engine RPM with the propeller control. This is only possible when the engine is running at high enough power, or our airspeed is high enough, to drive the propeller at the selected RPM. When we are setting up to land, we are at both low power, and low airspeed. Those factors are going to limit the maximum RPM that can be maintained with the propeller control. RPM will now fluctuate based on engine power and airspeed. And lastly, am I sounding like a broken record yet? - note the position of the horizon!

Mixture: Auto-Normal (lever fully back)
Propeller: ~2,100 RPM
Throttle: -3 lbs (-2lbs for 30 degree bank turn)
Flaps: Up
Elevator Trim:~1 1/2 Divisions Nose Up
Rudder Trim: As required
Radiator Shutter: Fully Open
Undercarriage: Up
Pitch: Bottom of gunsight glass level with the horizon
Airspeed: 140 mph
Rate of Climb: 0 feet per minute
Expected Radiator Temperature: ~75 C


Initial Approach

Having now slowed and stabilized yourself in the traffic pattern, it's time to descend. When we talk about landings, I will go into when and where to start the descent, but for now we just want to figure out our configuration for how we descend. Start by lowering the undercarriage, which will cause the nose to drop - expect this and don't allow it to happen. Keep it in the same place. Then reduce power to -6 lbs, and once again, the nose will start to drop, and once again, don't let it. Since you have more drag and less power, but you are maintaining the same pitch attitude, your airspeed will start to drop off steadily, and the aircraft will begin a descent. You will find yourself trimming full nose up elevator and you may still need slight elevator pressure. Airspeed will settle in at the prescribed 95 mph, and you will be in a roughly 1,000 foot per minute descent. Note that there is very little change in pitch attitude from your previous configuration. You will also notice that your RPM needle is at or near the bottom of the scale, even though you didn't touch the propeller control. At your leisure, bring the propeller control to max RPM. Nothing will change, but this step is important, since it ensures your engine will be ready for you to go to full throttle immediately if you need to perform a go-around.

Mixture: Auto-Normal (lever fully back)
Propeller: ~1,600 RPM (lever fully forward in case of go-around)
Throttle: -6 lbs (-5lbs for 30 degree bank turn)
Flaps: Up
Elevator Trim:Fully Up
Rudder Trim: As required
Radiator Shutter: Fully Open
Undercarriage: Down
Pitch: Bottom of gunsight glass level with the horizon
Airspeed: 95 mph
Rate of Descent: 1,000 feet per minute
Expected Radiator Temperature: ~77 C


Final Approach

In the final phase of the approach to landing, about 500 feet above the runway, we will lower the flaps and enter our final landing configuration. On most aircraft you will have one or two intermediate configurations as you lower your flaps in increments. The Spitfire has no incremental flap settings - it's all or nothing. Since they also significantly obstruct airflow through the radiator, I wait until the final segment of my approach to lower them, in order to keep engine temperatures lower. As you will see, flaps have a huge effect on radiator temperature in the Spitfire. So lower your flaps at about 500 feet. The nose will drop significantly, and this time you can let it happen, but not too low. Keeping the top of the black gunsight frame a little above the horizon will be about right. To maintain our steady 1,000 feet per minute descent, you will need to increase power to -4 lbs (you will see RPM rise with it, but you can ignore that). If you're keeping up with your rudder trim, you may find yourself at or near the starboard limit. Elevator trim is already at max nose up, so there is nothing to do there. I'll save everything else about landing technique for later, but you may find that just having a nice stable approach at an appropriate descent rate and airspeed solves most of your problems.

Mixture: Auto-Normal (lever fully back)
Propeller: ~1,700 RPM (lever fully forward in case of go-around)
Throttle: -4 lbs (-3lbs for 30 degree bank turn)
Flaps: Down
Elevator Trim:Fully Up
Rudder Trim: Fully Starboard
Radiator Shutter: Fully Open
Undercarriage: Down
Pitch: Top of gunsight frame slightly above horizon
Airspeed: 85 mph
Rate of Descent: 1,000 feet per minute
Expected Radiator Temperature: ~115 C


Go-Around

No pilot is perfect, and sometimes a landing approach just isn't looking right. Every pilot should be prepared for the possibility of a go-around on every landing. You have to earn the right to land, and if you haven't, you go around for another try. No harm, no foul. It is good to practice this maneuver as there is a lot going on at low speed and high power close to the ground. Your primary concern is simply aircraft control as you transition rapidly between two radically different phases of flight. You need to stop your descent, maintain airspeed, accelerate, and climb. The first thing is to increase power. If you followed your configurations earlier, the engine is all clear to bring in max throttle right away without fear of causing damage. But this doesn't mean we just slam the throttle forward. A smooth increase in throttle at a moderate rate is appropriate. In the Spitfire Mk.VA, we can go to full power, but with some of the more powerful fighters, full throttle isn't necessary, and might even lead to a loss of control. With the added engine power, you should stop the descent and begin to accelerate. The next urgent thing is to get the flaps up. Raising the flaps first before you have built up airspeed will cause you to keep dropping, but once you have accelerated past 100 mph it is safe to raise them. This helps you accelerate, and prevents you from overheating. A go-around without raising flaps in a Spitfire can quickly turn into a low altitude engine failure. During this whole time you should be fighting to keep the nose from going sky high. Remember your elevator trim? It's still at full nose up. Hold the nose down and get that trim setting lowered. If you fail to keep your nose from going too high, you can easily stall. Remember your takeoff nose attitude? Aim for that. In a real aircraft the stick forces can be really high as you fight the trim until you can reset it. It can be a bit of a workout. Once you are feeling on top of the aircraft, get your undercarriage up, and settle into a climb. Before you know it you'll be back at pattern altitude to level off for your next attempt.

Mixture: Auto-Normal (lever fully back)
Propeller: Max (3,000) RPM (lever fully forward)
Throttle: Max (+12.5 lbs boost at sea level)
Flaps: Up once above 100 mph
Elevator Trim: 1 Division Nose Down
Rudder Trim: Fully starboard
Radiator Shutter: Fully Open
Undercarriage: Up (when able)
Pitch: Bottom of gunsight glass level with the horizon
Airspeed: Accelerating to at least 140 mph
Rate of Climb: No descent, less than 1,000 feet per minute climb
Radiator Temperature: Less than 135 C


Key Points

A stable pitch attitude is critical to each of these configurations, and the best way to see pitch is by referencing the horizon. No amount of precision with the other settings will be able to compensate for being lazy about pitch discipline.

Known configurations take the guesswork out of flying. No more hunting for the right settings or micromanaging the aircraft because it won't stay where you left it. It is a lot to learn on the front end, but it builds familiarity and it starts to take a lot less brain space. Don't expect that you will be able to attain this level of mastery over the whole multitude of CFS3 aircraft however - at least not all at once. I only have enough room in my brain to keep up a few real ones and a few CFS3 ones at a time.


Concluding Thoughts

Your first time through this exercise is simply a fact-finding mission. You aren't trying to nail everything perfectly, and there is a lot of focus on the various gauges while you dial in your settings just right. Once you have settings you can trust, your high attention to the position of needles can be reduced as you become familiar with what "right" looks and feels like on subsequent practice runs. You will get to know very specifically what "right" looks and feels like in the aircraft you've chosen to learn, and much of that is going to apply more broadly in other aircraft. In the real world, you will find pilots who are laser-focused on numbers and fly precisely, but mechanically. You will also find pilots who lack precision, but have a very intuitive feel for what the aircraft is doing. The above method is aimed at balancing the two. It is closely tied to precision and hard numbers. Providing a predictable, stable, and efficient means of reaching them allows your feel for the aircraft to be based on an objective standard rather than feel based on feel. The numbers pilots can learn to trust their feel, and the feel pilots can ensure that their basis for what feels right is solid.


Happy flying!
 
Very detailed, Dan :applause:. I assume for 2 engine night fighters and 4 engine bombers, the principle is the same. i will have to see what pilot notes there are for those. In CFS3, is the auto mixture and prop setting more or less accurate?
 
Yes, the same principles apply in the same way to any aircraft.

Start with knowing what phases of flight you want to use with that aircraft, and determine the controlling parameter(s) for each one. The controlling parameters for each phase of flight for the Spitfire Mk.VA are marked in bold above. If you have a original pilots notes/flight manuals available, you can find usually find the specific airspeeds called out there. Specific climb or descent rates are less commonly defined there and you just have to find something that seems reasonable.

Next you need to determine the correct engine power settings and other aircraft configuration parameters for that phase of flight. You can often get these from the pilot's notes as well. There may not be a power setting called out for every phase of flight, so just do your best to come up some reasonable settings to fill in the gaps based on what you do have. Landing gear and flap settings should be self explanatory if not called out explicitly. Any miscellaneous settings are usually on an as-needed basis.

Then you need to find the pitch attitude that produce the desired airspeed or climb/descent rate when the aircraft is in the specified configuration. Reference the position of the horizon relative to an easily definable feature of the cockpit framing (gunsights often make great points of reference.) Make sure you are stable when you pick this point and note it precisely.

Lastly, determine the trim setting required to hold that pitch when in that configuration. Other than the. SJ Spitfire and Fw 190, CFS3 aircraft don't have working trim indicators, and many real aircraft didn't have an easily usable indicator anyways. Usually there is just a setting specified for takeoff. So this step is optional. You can use the Z key readout and see your trim settings that way if you want to. I do like the Spitfire's indicator and find it incredibly useful in all phases of flight, and that is one of the main reasons I chose that aircraft for the tutorial.

The way to transition between configurations is going to be more or less the same on any aircraft.

So to sum up, to use this method with any aircraft you need to do the following steps in order:

1. Define your phases of flight.
2. Determine the controlling parameters.
3. Determine appropriate aircraft configurations.
4. Find the pitch attitude that results in the controlling parameters being met in that configuration.
5. Find the trim setting that holds the desired pitch attitude.
 
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CFS3 Prop and Mixture Controls

The stock CFS3 mixture and prop controls are generic, and aren't too bad for simulating most aircraft, but there don't work exactly right for everything.

By default, most of our CFS3 aircraft do not have automatic mixture, which means mixture must be adjusted for altitude in order to produce the right fuel/air mixture in the engine. Since the air gets less dense as you get higher, you need to reduce the amount of fuel the engine is getting to keep the right balance. The vast majority of WWII had automatic mixture adjustment to reduce the pilot's workload. Setting the auto mixture setting in the realism settings will turn this on for all aircraft in CFS3, or you can turn it on for individual aircraft in that aircraft's aircraft.cfg. This gives generic auto mixture capability, but lacks an important feature that was present on the real aircraft. All of the actual aircraft had at least two auto mixture settings. One for high power (often called Auto-Rich or Auto-Normal) and an economy setting for lower power cruise (usually called Auto-Lean or Auto-Weak). In some aircraft this was set by the mixture lever, but in many there wasn't a mixture lever at all and the correct setting was automatically set based on the throttle setting. You can see this in the SJ Spitfires where the earlier Mk.Vs have a two position control, and the LF.Mk.Vs don't have a mixture control or have had it disabled. In CFS3 the stock auto mixture feature essentially only gives you the high power mixture setting.

The CFS3 propeller controls are a bit better for most aircraft. By the end of 1940, most WWII aircraft had a constant speed propeller similar to what most CFS3 aircraft had. You set a desired engine RPM using the propeller control in the cockpit and a governor system changed the propeller blade pitch continuously to maintain that RPM quite precisely.

The main exception is German aircraft (but may not bombers?), which often didn't have a propeller control lever. Instead, a predetermined ideal RPM was set automatically for a given boost pressure (manifold pressure). All the pilot had to do was set the desired boost pressure with the throttle and the RPM is set automatically. There was also a manual mode where the pilot could select a specific blade pitch (not RPM) manually. Some allied aircraft had the ability to set a pitch manually as well. Neither of these features is currently modeled in CFS3.

A slight difference in behavior you may notice is that most CFS3 aircraft can maintain max RPM at lower power settings and airspeeds than the SJ Spitfire, so you may not see the behavior I described in the landing phases until much closer to touchdown, if at all. Technically, most aircraft would have had similar behavior to what you see in the Spitfire in this respect.
 
How to Fly (Better) Entry #6 - Stalls

Stalls

Before we move into takeoffs and landings, I want to briefly cover stalls. One of the main cautions in the landing phases of flight is avoiding stalls, and in fact, the speeds chosen for approach and landing are based on that particular aircraft's stall speed.

A stall refers to an aerodynamic condition where the wing is no longer producing lift, or is producing very little lift. I'm pretty sure everyone here is aware, but just to be clear, when we are talking about stalls in relation to aircraft, we are talking about the wing, not the engine. We are just going to cover basic, 1 G stalls this time to keep it manageable. At some later point we can get into accelerated stalls and spins, but for this one we're just introducing the basics.

I will go into aerodynamics a little bit, since I think it helps you to be able to visualize the effect of your maneuvers on inducing a stall. A common misconception is that a stall always occurs at a certain airspeed on a particular aircraft, known as the stall speed of that aircraft. It is true that we reference a stall speed for each aircraft we fly and it is one of the most important numbers to have memorized when you fly. However, this airspeed is only valid when the aircraft is experiencing one G. If you are pulling more than one G, the aircraft will stall at a higher airspeed. If you are at less than one G, the aircraft will stall at a lower airspeed. Keep this in mind, because it is critical to understanding how to avoid and recover from stalls.

Instead of a specific airspeed that the wing always stalls at, there is a specific angle of attack, which, if exceeded, will always result in a stall. Angle of attack (AoA) is the angle formed between the chord line (the imaginary straight line between the leading edge and trailing edge of the wing) and the relative wind (the direction from which the oncoming air stream is hitting the wing). As you pitch up, AoA increases, which increases your lift. This is one of the things that causes you to climb when you pitch up. However, you can only increase AoA so much and continue to increase lift. As AoA increases, the relative wind is hitting the underside of the wing more and more. Eventually, it is hitting it at such an angle that the airflow over the top side of the wing becomes disrupted, which spoils the lift the wing is producing. We call the angle at which this occurs the Critical Angle of Attack, and the resulting loss if lift is called a stall. There is a lot of information on this readily available elsewhere if you want to go into more detail. This site lays it out pretty well, and even if you don't want to read everything, the diagrams will be helpful to take a look at: https://www.mpoweruk.com/flight_theory.htm

Hopefully that provides a helpful mental picture of the airflow around your wing. Going forward, keep that mental picture in mind, along with the following:

1. The stall occurs at the critical AoA.
2. To get out of a stall, all you have to do is reduce your AoA to anything less than critical AoA.
3. The only time the aircraft will stall at its published stall speed is when it exceeds its critical AoA at exactly one G.

So practically, how are we going to use this information? We don't have a published critical AoA, and we have no way to reference it if we did. Understanding AoA is critical to stall awareness, avoidance, and recovery, even if we can't see it on a gauge.


Awareness

Prevention is better than the cure, so let's look at how to stay out of this situation in the first place. We'll do this mainly by noting some situations where our AoA margin above critical AoA is going to be thin.

1. Low airspeed: When you are flying slow, your angle of attack will be higher. If for example, you are flying at low power and trying to climb or maintain altitude, you will have to pull back more and more to increase your AoA to maintain lift. But when you hit that critical AoA, the lift is gone and you stall. Low power, a high pitch attitude, and deceleration all exacerbate this condition.

2. Higher G loads: Just about any time you are pulling back on the stick, you are increasing your G load and AoA. This can happen at any speed.

3. Go-arounds: Here you are at slow airspeed, and the maneuver involves pulling up - both of these increase your AoA. You are also going from low power to high power, which can really mess with your rudder coordination, which can lead to a spin. Added to all of this is the fact that if you trimmed your elevator properly for final approach, your elevator trim is at, or nearly at, the full nose up position. When you apply power, your aircraft will automatically begin climbing, possibly quite sharply. If not anticipated and corrected for, this can lead to a stall very quickly and at an altitude too low to safely recover. With real life control forces acting on the flight controls, you have to get pretty physical with some aircraft, fighting the nose up trim until you can get it reduced. Thankfully, the limitations of our sim controls mean we don't have to deal with this here. If you have a force feedback stick though, you might get a bit of a feel for how that adds to a very busy few moments of flight. At any rate it's worth your virtual life to understand and anticipate all of the factors in play during a go-around that can lead to a stall.


Recognition

If you do find yourself approaching a stall, here are some signs you may be approaching, or in, a stall.

Air buffeting: As AoA approaches critical, the airflow over the wing is increasingly disturbed, and you can hear it. CFS3 models this rather nicely. In one STOL aircraft I spent a lot of time in, we flew STOL approaches based on the specific whistling sound audible in the cockpit at high angles of attack. It wasn't on the verge of a stall, but it was the very first warning sign and told us we were getting the slowest approach speed possible with a reasonable safety margin above the stall. I simply adjusted my pitch attitude until I got the right sound and flew that attitude to the ground.

Sloppy or unresponsive controls: As you approach the stall, your controls will feel increasingly mushy and ineffective, especially your ailerons.

Shaking: Many aircraft will experience some shuddering on the ragged edge of the stall. The Spitfire, for example, was known for warning it's pilots with a shudder before the stall which could be both felt and heard in the cockpit. I have modeled this behavior in the SJ Spitfires.

Nose drop: The definitive indication that you are no longer approaching a stall but are now in one, is a marked drop in the pitch attitude in spite of pulling back on the stick. On some aircraft this will be accompanied by a wing drop.

All of these characteristics will vary from aircraft to aircraft. Some are quite forgiving, others are rather nasty. The Me 163 technically doesn't stall at all and simply mushes forward. The Macchi C.200 has a wicked wing drop, and if it develops into a spin, isn't recoverable no matter how much altitude you have. Know your airplane.


Recovery

So you're in a stall. Now what? The following is the basic technique for recovering from a stall: Push, Power, Rudder, Roll, Recover.

Push: This is the most critical step. Push the stick forward firmly. This will reduce angle of attack back below critical AoA. This is known as breaking the stall. Hold this until smooth airflow is restored over the wing. Depending on how deeply stalled you are, this may require a longer or harder push. The important thing is to not cut this short. If you don't fully break the stall, you can induce a worse secondary stall as you try to recover. If you are inverted, you still push - don't pull! AoA only cares about chord line and the relative wind. Your attitude relative to the ground is irrelevant.

Power: Apply full power. No need to slam the throttle, but don't be lazy about it either. You can start increasing power while you are still pushing to break the stall. Remember - make sure your prop and mixture are set for full power first (if applicable to your aircraft) or you might add engine trouble to your scenario.

Rudder: Keep the ball centered (known as flying coordinated) with your rudder pedals. Uncoordinated flight will cause one wing to have a higher angle of attack than the other. If you get one wing below critical AoA, but not the other, you will have a spin on your hands.

Roll: Once the stall is broken, you have full power, and you are flying coordinated, you can counter any wing drop or rolling that occurred during the stall. It is important to wait until all of that is accomplished, before applying any aileron inputs other than neutral. This is because just like flying uncoordinated, ailerons cause your wings to have different angles of attack, and you don't want to spin.

Recover: You have broken the stall, you have applied power, you are flying coordinated, and the wings are level. With the stall combined with all of that pushing, you are probably in a nose low attitude, so now it is time to stop accelerating towards the ground, and get your nose attitude back up where it belongs. It is important not to do this too suddenly, since you are once again increasing AoA. A sudden jerk back on the stick can put you right back into a stall. Be smooth. In fighters with high speed and G limits, a lot of acceleration isn't necessarily a bad thing, but in other aircraft not built for that kind of abuse, you need to make sure you are doing this in a timely manner so as not to overstress the aircraft as you pull back to a normal flight attitude. As you enter a level flight attitude or a climb, confirm with your vertical speed indicator that you aren't still descending. Now you can start reconfiguring your aircraft back to the appropriate settings for whatever you were trying to do before the stall.

Note that all of this can happen very quickly. Only a second or two with practice. If you have altitude, you have time, but if the trees and houses are looking big, every millisecond counts. With practice you will get a feel for just how fast you can be without inducing a secondary stall.


Practice

Let's take a plane out and practice stalls with it. For consistency, I will use the SJ Spitfire Mk.VA again. You can follow along in that aircraft or pick a different one. We are going to do some things to demonstrate stall behavior, you can practice the Push, Power, Rudder, Roll, Recover method, and we will note the 1 G stall speeds with flaps up and with flaps down. If you are using a different aircraft and don't know what a good landing approach speed is, we will go over how to calculate one based on your stall speed.

So, let's set up in the landing pattern configuration, but with plenty of altitude, let's say 5,000ft. Since we want to be ready for a stall recovery, make sure the mixture is set to Auto Normal and the propeller lever is fully forward. Start a gentle climb and pull the throttle to idle. As you decelerate the nose will want to drop. Hold the nose up, and watch for the warning signs of an impending stall. Keep an eye on the slip indicator and keep the top needle centered (or keep the ball centered if you're not flying a British aircraft) to maintain rudder coordination. Right as the nose drops into the stall, note and record the airspeed reading. This is your flaps up 1 G stall speed. Now initiate the recovery procedure outlined above.

Starting Configuration:
Mixture: Auto-Normal (lever fully back)
Propeller: RPM lever fully forward
Throttle: -3 lbs (-2lbs for 30 degree bank turn)
Flaps: Up
Elevator Trim:~1 1/2 Divisions Nose Up
Rudder Trim: As required
Radiator Shutter: Fully Open
Undercarriage: Up
Pitch: Bottom of gunsight glass level with the horizon
Airspeed: 140 mph
Rate of Climb: 0 feet per minute
Expected Radiator Temperature: ~75 C

Now set up the same way for another stall. As before, keep coordinated on the rudder. This time, at the first warning sign of the stall, pull sharply back on the stick. This will cause a rapid momentary increase in AoA, and induce a stall early. Note that the airspeed at this stall was higher than the 1 G stall speed you recorded earlier. This is just to demonstrate how the stall is directly dependent upon AoA and not airspeed. Initiate the stall recovery procedure.

For our last stall, we are going to set up in the full landing configuration with flaps and undercarriage down and in a descent. Once stabilized, bring the pitch up so the nose is a little above the horizon and hold it steady until you see the nose drop and you stall. Remember rudder coordination as always. Record the airspeed reading at the moment the nose dropped. This is your flaps down 1 G stall speed. This time, perform the stall recovery and then go straight into the go-around transition.

Approach Configuration:
Mixture: Auto-Normal (lever fully back)
Propeller: ~1,700 RPM (lever fully forward in case of go-around)
Throttle: -4 lbs (-3lbs for 30 degree bank turn)
Flaps: Down
Elevator Trim:Fully Up
Rudder Trim: Fully Starboard
Radiator Shutter: Fully Open
Undercarriage: Down
Pitch: Top of gunsight frame slightly above horizon
Airspeed: 85 mph
Rate of Descent: 1,000 feet per minute
Expected Radiator Temperature: ~115 C

Go-Around Configuration:
Mixture: Auto-Normal (lever fully back)
Propeller: Max (3,000) RPM (lever fully forward)
Throttle: Max (+12.5 lbs boost at sea level)
Flaps: Up once above 100 mph
Elevator Trim: 1 Division Nose Down
Rudder Trim: Fully starboard
Radiator Shutter: Fully Open
Undercarriage: Up (when able)
Pitch: Bottom of gunsight glass level with the horizon
Airspeed: Accelerating to at least 140 mph
Rate of Climb: No descent, less than 1,000 feet per minute climb
Radiator Temperature: Less than 135 C


Stall Speeds and Approach Speeds

I have repeatedly mentioned how angle of attack determines when an airplane stalls, and not an airspeed, so now we need to talk about the usefulness of stall speeds. The stall speed, being more accurately called the 1 G stall speed, is very important to keep in mind, particularly during the takeoff, initial climb, and approach and landing phases of flight. These phases all occur at 1 G, when we are low and slow, or in other words, when we are the most susceptible to stall with the least opportunity to recover. Note how we recorded two stall speeds for the Spitfire. One with flaps up, and one with them down. On aircraft with intermediate flap settings, there is a corresponding stall speed for each. It is important to know what they are for your aircraft so you can make sure to give yourself an adequate margin of airspeed to stay safe in these phases of flight. Thus, you also want to be aware of, and be disciplined about holding, the correct climb and approach speeds. While climb airspeeds are determined by a variety of factors, approach and landing speeds are based directly on the stall speed of the aircraft. A margin of 1.3 times the stall speed is generally what is used. This gives you margin in case you encounter a gust of wind, turbulence, or get momentarily distracted, and drift slower than your intended airspeed. If you look at the manual included in the SJ Spitfire Mk.V, you will find a flaps up stall speed of 73, and a flaps down stall speed of 65. These correspond to the flaps up and flaps down approach speeds of 85 and 95, respectively. In both cases the approach speeds are very close to 1.3 times the corresponding stall speed. So if you are wanting to find a good approach speed for an aircraft but don't have a manual for it, you can simply find the stall speeds for that aircraft in each flap setting, and multiply them by 1.3 to get good, safe approach speeds.
 
Most CFS3 aircraft have data on the various stages of flight in the 'help' folder, although I must confess that I, probably along with most, don't read and pay attention to that before flying. I should do so! I think that I might take out those files to another place for easier access on another monitor or to print out. These were mostly done by AvHistory and I assume apply to their aircraft models, even though ETO and TOW aircraft keep the same. How thay compare with reality is something I have yet to check.
 
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