Acceleration comparisons

[horseback]

Originally Posted by JtD

Regarding trim, both the F4U and the F6F as tested by NACA required loads of elevator trim. Stick force changes were in the range of 30lb between 200 and 400 mph in level flight. Trimmed for neutral stick forces at low speed, pilots would sometimes not be able to keep the aircraft in a dive.

Trim as suchs seems to have been a bit more effective than it is in game.

I use Francis Dean's America's Hundred Thousand as my primary reference in these things, as well as Barrett Tillman's The Wildcat in WWII, Hellcat: The F6F in WWII, and Corsair: The F4U in WWII and Korea to supplement for 'hard knowledge' on these particular aircraft. I've also had many occasions to talk to men who actually flew these aircraft (my landlord in Coronado many years ago was a former Wildcat, Hellcat and Corsair driver, getting combat time with the Grummans in WWII and with the F4U in Korea; he introduced me to several of his wartime buddies after he noticed my extensive model collection --and bought all my blue airplanes).

On trimming the Corsair, America’s Hundred Thousand says: “The Corsair was easy to trim out for climb. Trim changes from landing gear and flap retraction were minimal, and those for speed and power changes were quite handleable. In cruise condition the airplane could be trimmed for hands and feet off flying with little trouble. Pilots almost universally rated F4U-1C and -1D trimmability as good. In a dive, as with some other US fighters, a considerable amount of rudder trim was required to zero out pedal force which was high if this was not done.”

One the Hellcat’s trim characteristics, it says: “There were nose up trim changes with gear and flap retraction, though they were minimal, and the same was true of initial acceleration into climb. In general, there were substantial both directionally and laterally with speed and power changes, but tab action allowed trimming out control forces to zero except for the rudder. At low speed and high power rudder pedal force could not be trimmed out fully. Most pilots thought trimmability was generally good, though some made the following comments ‘Lack of trimmability”, Excess rudder trim change”, and “Aircraft requires excessive trim” (three pilots). It was noted that in a dive control forces could not be trimmed out quickly enough.

The old Naval aviators I talked to felt without exception that the Hellcat was the easiest aircraft they ever flew off a carrier deck, prop or jet. Of course, most of these old guys were raised on farms or worked at a job demanding a fair amount of physical strength (by modern standards) so a 30lb force difference probably wasn't all that excessive by the standards of the time, especially if you could easily adjust it out with the trim tabs. To be honest, 30lbs (or a bit less than 14kg) doesn't sound like that much to me, but I spent many hours in the pool and the weight room as a younger man.

In-game, trimming out these aircraft is not close to 'easy'.

The point is that many of the aircraft modeled in this sim are based on reports and tests done 70 years ago, and what were called 'mild' or 'light' stick or rudder forces might seem a bit heavy to the average man today. It may not be appropriate to add (over)detailed characteristics to well understood and documented aircraft that have to compete with aircraft that are modeled on older standards that cannot be verified to match the current ones.

Now if you all will excuse me, some miserable sod has released a new patch, and I have to start re-running all of the 100m tests I've done so far...

cheers

horseback

PS: During the early phase of my tests, I ran the trim all the way out in both directions on a number of aircraft, doing both rudder and elevator, as well as a few ailerons; it takes 80 button pushes in each direction from CENTER, or 160 button pushes from one extreme of trim offset to the other. By comparison, using the CH Quad, a tiny increment seemed to have much greater, but much less predictable results. Pick your poison.

[MaxGunz]

UDPSpeed and UDPGraph will let you put data on-screen while flying offline which I think could include acceleration indicator which should allow dynamic testing to see what effect you could achieve. The hardest part is setup and there were walk-thru's on that last I remember. It's like the difference between hand tools and power tools, once you got power tools they can be a pain at times but mostly tend to put a smile on your face once you get used to them.

The parallax effect is probably due to being in right-eye gunsight mode. Switch back and see, it is easier to fly most fighters in centered view. Up close it's even easier to shoot that way, with practice.

Really, in-game since the start I've found the smartest thing to do before maneuver combat is to neutralize trim and avoid hard G's that lead to wingtip stalls or worse. Slip... easiest to avoid in a P-51 with mini-ball gunsight and hardest in the Spits. We NEED a slip indicator in the speedbar to replace what can be felt IRL.

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Back in December I thought to interface Arduino to IL-2 but first there was an MP3 module to deal with. It took over 4 months to find out that the fix is shorting 2 whisker-tiny pins on a surface-mount chip which no way I can do so now there's a new module that's got its own hangups... 115200 serial may not work well breadboarding or I dunno what else is the hangup -- I'm a programmer who can do some hardware so aware that I have my own hardware limits. This will be either GO or NO GO, I won't try another, and then on to other pursuits that have been on hold like an autopilot robot.
As it is, I think my forehead is flat and I have no hair above my ears/eyebrows.

Today, after reading about trim I got a real narsty idea... the same controller that runs the stick could be made to do "smart trim", couldn't it? Or maybe not, having the nose seek to bring the stick to center after some-odd seconds might be a bad thing at times, like when you're just about to shoot! Perhaps a button, like I asked Oleg for back in 2002.

[horseback]

Originally Posted by MaxGunz

The parallax effect is probably due to being in right-eye gunsight mode. Switch back and see, it is easier to fly most fighters in centered view. Up close it's even easier to shoot that way, with practice.

Really, in-game since the start I've found the smartest thing to do before maneuver combat is to neutralize trim and avoid hard G's that lead to wingtip stalls or worse. Slip... easiest to avoid in a P-51 with mini-ball gunsight and hardest in the Spits. We NEED a slip indicator in the speedbar to replace what can be felt IRL.

Today, after reading about trim I got a real narsty idea... the same controller that runs the stick could be made to do "smart trim", couldn't it? Or maybe not, having the nose seek to bring the stick to center after some-odd seconds might be a bad thing at times, like when you're just about to shoot! Perhaps a button, like I asked Oleg for back in 2002.

Since getting TIR about seven years ago, I hardly ever use the Toggle Gunsight button, particularly since 6DOF was introduced in the stock game. The parallax is there from either view in every case, and I assume that it is there as a result of 'artistic license', because it isn't visible in any pictures that I have on hand of existing aircraft (Kinzey's Detail & Scale series has excellent cockpit photos for each of the WWII US fighters, in most cases including extensive shots of each variant) or my own observations in museums and air show displays.

I like the suggestion about neutralizing trim once maneuvering begins, but I believe that the trim models for these aircraft need to be put in line with the other 'stock' aircraft in the game, or that we get a short-term HUD display indicating your trim displacement every time you make an adjustment (like when you change radiator, PP or throttle), so that you know just where the hell you are in terms of trim state--as I pointed out in earlier posts, a RL pilot would roll in more trim to a pre-set point in anticipation of a dive or increased throttle.

I've also been toying with making a trim box with a 20:1 gearbox on each pot so that I can make the teeny-tiny adjustments to my pots that the game demands (and how is it that one button press of 1/80th of total deflection is so necessary?) and at the same time make the larger changes for something I'm about to do.

cheers

horseback

[JG27CaptStubing]

Interesting to see what TD did to some of the FWs... No wonder you can easily get caught with your pants done

[Mustang]

Great Post Horseback !!

Thats take long time to do.

But now...
what aircraft are OP ? vs RL

[horseback]

Originally Posted by JG27CaptStubing

Interesting to see what TD did to some of the FWs... No wonder you can easily get caught with your pants done

To be fair, this set of tests were done at just about the worst possible height for the FW; 3000m is quite close to the alt at which its supercharger moves from low to high blower, so the engine is not at its best here. I've just started doing the sea level (100m) tests, which should be more flattering to the Wurger.

cheers

horseback

[IceFire]

Probably a good idea to point out that context is extremely important. As these acceleration tests were all done at the same altitude. Some aircraft will be better and others worse at this altitude... nothing stays the same across the range. It's not one acceleration level that extends from 0 to 10,000 meters.

You have to know your plane. I know that the Tempest V between 3000 and 4000 meters is less capable against the FW190D-9 (which I consider to be its chief rival) as the stage 1 supercharger starts to run out of steam and you're just about to switch to the stage 2. Depending on the D-9 model year... this is the worst altitude to fight at. Take it lower or higher and the Tempest is faster and more able. Context!

[MaxGunz]

I would have problems with a plane that didn't get noticeably more lift for a 6 mph speed increase.

Check around, there are 10-turn and IIRC 20-turn pots in various ranges.

Less fine-adjusting but oh so desirable, check the unit price:
http://www.futurlec.com/PotSliding.shtml
There is a shipping charge but that can be as low as $4 to $5.
http://www.futurlec.com/Delivery.shtml
The package comes from Hong Kong so expect about 2-3 weeks wait.

Something else you could do is put a 10k or smaller pot in series with a 100k pot (or a 1k and 10k) and have both coarse and fine adjustment knobs on the same circuit.