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FSX Warbird Start-ups...

L

letsgetrowdy

Charter Member
Hi guys,

Just something on my mind, I seem to have noticed that in FSx, out of all the warbirds that I've flown, none of them have realistic start-up characteristics.
I have seen a considerable amount of warbirds (eg Spitfires, hurricanes, Mustangs, etc ) at airshows, and have always taken note of how the airscrew comes into opporation when the starter is pressed:

In FSX, for example some of the A2A birds, be it the Spit or P-51, when the starter is clicked, the prop jumps into full motion immediatly, without making any slow motion first.

In reality, these types of powerful piston engines will ALWAYS have a very slight hiccup before jumping into full spin, be it hot or cold.

Take note of these youtube videos, which show a few start-up procedures, and you'll see what I mean.

http://www.youtube.com/watch?v=cv0Onh6NzPA

http://www.youtube.com/watch?v=-sjqir7YzVQ&feature=fvw

http://www.youtube.com/watch?v=xSyVL0D02tY

One can see that a heafty fuel filled merlin like one of these will have complete around two or three slow full revolutions of the prop before the spark will catch and the engine barks into life, as opposed to the usual FSX way of just reacting immediatly.
Also, if the outside temperature is cold, is the Spitfire you would give around a half a dozen shots on the Ki-Gas primar at the carb, meaning that the extreme richness of fuel can result in licks of flame coming from the exhaust stubs, which I have also never encountered in FSX.
 
Also, if the outside temperature is cold, is the Spitfire you would give around a half a dozen shots on the Ki-Gas primar at the carb, meaning that the extreme richness of fuel can result in licks of flame coming from the exhaust stubs, which I have also never encountered in FSX.
Click to expand...

I think you could program the model to do that, set a flag so that if the primer has been used it runs an effect for a couple of seconds that has flames coming out of the exhaust. It'd have to be done with the original model I think though to add the primer to the cockpit and the effects to the exhaust.
Not totally sure about the slow start up as that's determined by the FSX engine model, you might be able to emulate it with some clever modelling....
 
The only model I've ever observed with these signs was the Fs9 Plane Design Spitfire, which gives the proppeller two slow circles with the starter and booster coils engaged, with the starter sound.
Out of all WBs I've ever flown on FS, this was the most realistic in this respect.
 
Yeah, that is one of the issues of the VS Hellcat which I bought while it was cheap, you can put the mixture to rich, no prime or anything, hit the starter and in the same moment the engine is running purty at idle, no slow prop turning, no stuttering start, no problems keeping the engine on at low rpm... Even the default Cessna is harder to start....
 
GBrutus said:
Ah, what I'd give for an FSX version of the Plane Design Spitfire...
Click to expand...

Now Brutus, around three months ago I set to work on trying to port over the plane design Spitfire 16 into FSX and resulted with mixed success.
I managed to,

- Convert the BMP files in 32-bit DDS and creat partial alpha channels for
the texture

- Correct the opaque propeller in FSX Acceleration

- Correct the opaque VC class textures into transparent ones

- Correct the odd flight handling characteristics

However I didn't manage to fix the problem which resulted in about 1/2 of the gauges not showing the counters.

If anyone would like me to upload what I have fixed so far, please say.

Mr. Mugel, I quite agree that the Hellcat is exactly what I'm talking about.
Wozza, glad to see the Texan coming along well. What I'm saying is the start up procedure on the A2A birds is realistic, just not the way the prop reacts to the starter. That sudden jump into life I can't see realistically. When, eg I saw a real Spitfire MK. I start-up at Duxford, the prop completed a whining, slow revolution of the prop, then slowed even more, emitted a flicker of flame from the exhaust, sped up then started up...
 
letsgetrowdy said:
.
Wozza, glad to see the Texan coming along well. What I'm saying is the start up procedure on the A2A birds is realistic, just not the way the prop reacts to the starter. That sudden jump into life I can't see realistically. When, eg I saw a real Spitfire MK. I start-up at Duxford, the prop completed a whining, slow revolution of the prop, then slowed even more, emitted a flicker of flame from the exhaust, sped up then started up...
Click to expand...
Ahhh that a whole different kettle of fish :)
FS needs almost 500rpm before combustion starts,factor in that prop_still animation looks real bad at anything over 40rpm.You can alter the animation timings and some of the engine/prop params but there is a either a problem later down the chain or you loose the ability to start the engine 9 out of 10 times.Ive set up the slow prop on the texan to stutter as it passes the compression stroke but even though it looks real good in shut down,due to the high RPM of the startup you cant even notice it meh at least I try ;)
Wozza
 
Realistic starting has always been a problem with the FlightSim series. For FSX, A2A has, so far, the best starting and engine management with their AccuSim package, but that is only available on their Boeing Stratocruiser, WOP3 P-47D razorback, and their new Piper Cub. Wozza has developed an electric inertia starter with a pretty good prop animation, although the single push button to energize and engage is not exactly correct.
 
Fighters aside, in larger aircraft such as the C-46 and DC-6 and others, the starter is engaged and you count blades for up to 20 seconds, before you fire mags. FS has never yet provided this ability and this has been a personal gripe since way back. Animation challenge I guess, or just not enough demand.

Alexdan
 
Nice to see the old Spit is still liked - I was rather proud of the startup sequence I designed for it! It involved a lot of messing around, but I was embarrassed into doing it when I was doing some "on site research" and was able to stand right by a Hurricane starting up. The way it starter was so different to the FSX startup sequence that I just HAD to figure out a way to make it work.

I've got a lot on my plate right now, but I'll see if I can pull out the source files for the Spitfire and fix the problems with the gauges in the next month or two. I've looked at the problem before but frustratingly wasn't able to get it to work reliably on different systems.
 
Yes IanP. I got all the A2A Accusim stuff. More power to them...

I fly what I know, err.. knew, - pre 1950 stuff, and it isn't really a big selling area for developers, other than fighters.:kilroy:

Best

Alexdan
 
Ed Walters said:
I've got a lot on my plate right now, but I'll see if I can pull out the source files for the Spitfire and fix the problems with the gauges in the next month or two. I've looked at the problem before but frustratingly wasn't able to get it to work reliably on different systems.
Click to expand...

Great news! I bought the PD Spit just to have a go at trying to port it over to FSX, having never had FS9, and I said above, had mixed luck.
 
Rotating the blades around, typically 6, 8, or 10 blade counts, is certainly an important factor when starting up a large-piston engine. It has been something that has been on my mind, and I definitely will try and figure out some way of animating it as well with future releases. The point of it is so that you don't do any damage to the engine on start up - any gunk that may have built up while sitting out, could do damage to the piston rods or other parts. At the same time, you usually pump the primer for every blade as it crosses - or keep the automatic primer on for the duration - so that you have the engine prepared for the ignition to be unleashed.

Of course it would be great to have a functioning primer for once, so that you could have an even more realistic start sequence, where the mixture is the last thing adjusted to keep the engine running. Whether you are starting a B-17, B-25, P-51, P-47, P-40, or any other warbird of that nature, you start the engine only on the primer - giving shots of primer, while holding the starter, then trowing in the ignition, and finally when it turns over, throw in the mixture.
 
One additional problem with having a truly realistic starting sequence is that you have only one mouse in a sim. Starting a real reciprocating engine involves holding the priming switch, energizing/engaging the starter and switching on the magnetos. Real pilots use both hands, try it with a single mouse pointer. Now you can "cheat" a bit by assigning functions such as the starter switch to the keyboard. I have and it does make things easier. I'm kind of weird with flight sim, I go through all the gyrations of a real engine start, knowing that priming and such is useless in the majority of flight sim aircraft.
 
Guys have a look at this video from the 1980's showing Spitfire IX MH434 completing a start-up procedure and flight. Again, notice the two slow revolutions of the prop when the starter and booster coils are pressed, and then the engine turns over and chugs into life and smoke is released from the exhaust.

http://www.youtube.com/watch?v=FzsJBjbCyvM

Of course, what would also be great would be the ability to complete a walk-around of the exterior model, checking for damage etc.
 
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