Would I have survived?

Paul,
I think it would be enough to fix the rules clearly next time.
Like, clearly state that take off, cruise and descent/approach are mandatorily to be flown according to the POH/handling notes supplied with the plane, and that no flying ourside of the "recommendations" (and "Limitations") is allowed.

Actually I like Charlie3/7's statemen that "the mixture/MAP/RPM/Fuel flow graph has been arrived at by many,many years of trial and error and
hard won experience." to make such rules comprehensive to everybody, even me.

If this is stated in simple terms, bold letters, and not exceeding 10 lines, at the beginning of the rules, then even I may actually understand it. :d

I think we'd all respect such unenforcable rules without need for tracking and control (except maybe for the RTWR, which, I feel, can get quite
competitive).
There's of course the danger that somebody with little experience (that was clearly the case for me this time), or with a plane that does not have
good documentation, or a plain unrealistic flight model, may fly outside of the realistic envelope. So what.
I think we'd have fun nevertheless.

In any way, you at SO did a terrific job designing a race format that promotes racing in a realistic environment, which I would love to see in further events.
And I'll do my best to conform next time - and finish well nevertheless. :d

Cheers,

Gunter
 
Would I (and the plane) have survived the trip?:engel016:

+ What would have happened to the engines?
- Would the engines have worked at all with very lean mixture?
- Would the plane have arrived at all at a leg's destination or would the engines likely have failed in flight?
- Would the engines (and other parts) have to be changed after each leg?

+ Would the real plane have behaved the same way regarding fuel consumption/speed, or is it a quirk in FS that consumption decreases so much with very lean mixture?
Click to expand...

I was never a Connie flight engineer, but I knew/ know several. I've also been on several Connies when an engine had to be shut down, and one memorable occasion in the cockpit landing at Danang with both engines out on one wing.

Time frame is important. Any Connie flying today will be flown very carefully and the engines treated like newborn babies.

In 1972-74 when I flew on them, parts and engines were beginning to be hard to find. While every plane which was sent to the boneyard was a potential warehouse, the long range quality of the parts was always a question. We had easier access to P-3 engines with only two aircraft, than Connie engines with seven aircraft.

In 1949, the Connie was a new top of the line model, and pushing the numbers to set fast trip times was common.

In a contest such as the Evita was framed, all the airlines would have pushed their crews to fly as close to, or slightly over, the high end numbers as possible.

The Wright 3350's had two banks of nine cylinders for each engine. As many hours as you flew, it would be unusual to not change at least one cylinder. Those cylinders could be removed from the outside of the engine and replaced within a couple hours. We always carried spare cylinders in our onboard parts kit.

I remember we did checks on the cylinders, pistons and such after 20-25 hours of flight. The FE and the mech would be out soon after landing putting their hands on cylinders trying to see if one was too hot or too cold.

We seldom burned a piston. I don't remember breaking a connecting rod or crankshaft. I do remember some broken valve rods, but the most common problem when an engine got too hot was an indication of metallic chips in the oil, or a bad oil pressure indication.

I had an old FE tell me a year or two ago how much he would have loved the current sensor technology to tell him the cylinder head temp for each cylinder which is available on some relatively cheap GA aircraft today. Though he wondered how to keep track of all 72 cylinders.

We really don't fly realistic often. We don't have the two main penalties - the cost and the possibility of death. It is hard not to push ahead a bit.

I flew the Lancastrian a bit hot, but I kept everything in the green. Not in the middle of the green, on the upper edges, but in the green.
 
Reggie, thanks for the insight. We do have some people with some amazing experience here. :applause:

I suspect that the main point where I veered from realism was really the ultralean mixture I flew with.

I had an excess of about 50% air in the mixture I believe (vs a stochiometric mixture fuel/air), and at the same time pretty high power.
- Do you think that with such ultralean mixture the engine would have worked at all?
- Would there have been detonation :pop4: (the higher the MAP/pressure in the cylinder, the higher the temperature increase after the compression cycle, no?) or other effects destroying the engine? (Btw, CHT was in the green during flight).
- The engine should at least have run very rough, no?

What do you (and others) think about that?

In fact I suspect that the FS model of engines is not accurate in so far as the effect of mixture is concerned.
As far as I understand, from what I have read in the meantime, in reality the Brake specific fuel consumption (BSFC=FF/BHP, fuel flow to achieve a given BHP) is lowest at maximum EGT-50°F or so, and should increase again if the mixture is leaned further. However, it seems that with the model I have flown, it decreased further with leaner mixtures.
Should be pretty easy to test within the sim, but I can't fly for the next two weeks or so to test that.

PS: This is all new to me, so I may have completely misunderstood the functioning of the engines. May be BS.
Btw, I liked the following presentation on how an engine works:
http://www.njsflight.com/resources/general.html - High performance engine operation

PPS: - I was in the green everywhere as well - temps, pressures, ect. (though I exceeded the rec to stay below 43 psi, MAP was still in the green as well).
 
PPPS: I had looked at the flight parameters with AFSD: TO power was Shaft horsepower (BHP?)=3280 HP (per engine, max_rated_hp=3250 HP), cruise was about 2140 HP, i.e. about 67%.
That's not straining the engines too much, isn't it?
 
The issue is not how FS models engines, or specific components of engines.

The issue is how modelers design their engines and their failure to use the capabilities to model damage.

While there are some things you can do with aircraft to cause catastrophic damage, only a very few designers work with cumulative damage.

One of the things I like about the FSD aircraft was that the impact of running an engine improperly over a period of time would cause the aircraft to have poor performance.

If modelers would write their flight dynamics to keep track of engine hours, to keep track of abusive flying and institute degraded engine performance - that would make a lot of people fly much more realistically.

But they don't do that because the FS community does not want that type of aircraft.

One of the reasons I like Copley's P-38 is that you can hear the engines running poorly when the mixture is off.

I do remember one FE who told me that listening to the Connie engines was important to get the best performance. I don't ever remember seeing all four mixture controls at the same setting in cruise. All the engines on our aircraft had different hours on them, and each engine needed to be set individually for best performance.

Low mixture, high MP, etc - among the problems which can occur are burning spark plugs and fouling spark plugs. Given the region and the stops, the possibility of off octane fuel was high. I don't think FS can simulate an 18 cylinder engine losing a cylinder because of fouled plugs, something I have experienced in real life.

Flying "by the numbers" is an approximate. Without the aircraft POH, you really cannot set the correct numbers for your flight. The numbers for the Rio to Sao Paulo leg would be different than the numbers for the Atlantic crossing leg.

And with recips, each plane, each engine varies those numbers a little.

Flying by the numbers is a range, not a this number MP and RPM only idea.

The crew has to make the decision about the tradeoffs. Pushing the plane to ultra lean mixture could easily have not had a negative impact upon the 30 hour or so flight. But it would have had an impact on the life of those four engines.

The 3350 was never cheap - as I said above we can never come close to the cost factor in flying, which is so very important in the real world.
 
Reggie, thanks for the comments and explanations.

RFields said:
But they don't do that because the FS community does not want that type of aircraft..
Click to expand...

I for one, would love to have a real-to-life sim of a plane - I think... :kilroy: And you would as well, I bet!
If there's the material available to learn the proper techniques, and if I can ask stupid questions on the forums. Just would keep it a simple plane not to be overwhelmed.

RFields said:
The 3350 was never cheap - as I said above we can never come close to the cost factor in flying, which is so very important in the real world.
Click to expand...

Now, how would that be - the sim fries the processor as a function of the damage to the engines. :d
 
If you had a real life sim of a Connie, you would require at least one, probably two other people to fly it.

A sim of those big old recips simply could not be flown realistically by one person.

You would have to spend close to an hour pre-flight. I never remember less than 15 minutes pre-takeoff runups and checks right before takeoff.

You would have to spend 40-80 hours with the manuals before you ever fired an engine.

The sim does a good job of giving us a close feel for some of the complexity of these big planes. But flying them was so much more than following checklists and procedures. A lot of it was experience which can only be gained in the aircraft.

I really think the Evita event was a pretty good test under near realistic conditions. Just like a real airline pilot, you made a risk/ reward decision as to how hard to push the plane. The damage modeling could have been better and penalized you more for long term engine abuse. But the fact that you are questioning your decisions and their impact shows the event achieved it's purpose.

Something Indy Car driver Eddie Cheever said once kind of sums it up "The moment I knew I was a race car owner, and not just a driver, was at Dover. I was skidding toward the wall and realized I was worried about how much the crash would cost, not how much hitting the wall would hurt."

When I take to the air in that real Light Sport Aircraft for a lesson, I am very aware that if I push the plane past the limits set by the school, it will cost me money. Hard earned green folding cash.
 
I have finally done some testing of aircraft performance with AFSD, and it seems that BSFC decreases strongly with very lean mixtures for the fs9 piston engine planes.

As this is getting quite into details of the fs9 engine model, I have started a new thread over at my usual lair.
http://forums.flightsim.com/vbfs/showthread.php?t=200852
However, if you can help me understand this, it would be great if you could drop in over there.

Thanks,

Gunter
 
Thanks to the race committee for all the research that goes into the events. I don't have a lot of time to test prior to these events so the background information is useful. The fuel penalty made sense, but I am still not sure I quite grasped the payload bonus properly. I tried to estimate my fuel consumption and pick a payload that would hopefully not put me above max landing weight and would allow me to take off and land on some of the more challenging fields.

As Reggie points out, you don't have anything on the line when you are sitting at your computer, unlike when you are operating a real aircraft. It would be great if there was an engine wear model over time that could be applied to the RTW. Until then, I think it will come down to plannign and teamwork and not crashing on takeoff and landing to be succesful.


Reggie - Are you working on your Light Sport? I am very interested in that myself as I just want to fly around and control an airfram in all phases of flight and not have to pay for extensive cross country training that I will never have the money to take advantage of.

Cheers!
 
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