Thread: Bf109E-3
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Old 05-13-2011, 05:44 PM
Blackdog_kt Blackdog_kt is offline
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Quote:
Originally Posted by 609_Huetz View Post
Gonna be interesting to see what you can come up with. After some messing around in the good ol' 109. 480-ish is the absolute max I could squeeze out of her and hold on the deck.

One thing I that may cause issues for people is controling prop pitch by buttons on your joystick rather than using an extra axis-controler. Fine adjustments are almost impossible to achieve with buttons.


Ok, i did some quick and dirty testing before going to bed last night and it turns out that i can't maintain 500km/h after all, but it's not off by too much.

I confirmed speeds by temporarily disabling my head-tracking and placing the mouse over the IAS gauge to keep the pop-up readout of the instrument displayed during the entire test.

I assume that by top speed we mean running flat out but with temp effects and CEM on, so i tried to use the highest possible settings that won't damage the engine.

I firewalled the throttle and activated WEP (which the sim calls "afterburner" and automatically disengages after a while, default key for this is backspace), trimmed nose heavy and started descending to the deck. I easily got 460km/h and by playing with trim and pitch a bit more i managed 470km/h.

I tried further coarsening the pitch but got no noticeable increase.

Never the less, maybe it can get there with further efforts. For example, i don't have a spare slider for pitch so i use buttons on the stick to increase/decrease it, which don't really give that precise of a control. Maybe someone with a second throttle/slider could achieve the missing 30km/h. Perhaps the devs will implement a closer representation of how the pitch control operated and we might be able to overcome this regardless of what controls we use.
It was much more gradual in reality than the way it currently works in the sim, where we get about 20-30 minutes of change of the prop pitch clock indicator for every key press. After reading a link posted in another thread, it seems that 10 minutes on the clock corresponds to 1 degree of prop angle, so it seems like the smallest amount of pitch change for someone using keys or buttons is not less than 2-3 degrees of pitch.
That was a very helpful link, i hope the guy who dug it up won't mind me linking it here too: http://marseillegruppe.com/foro/view...f328cb9d3b84f4

Another thing is that i didn't have the rads completely closed. Water rad was between 1/3 and half open, the oil rad was about 1/3 open. I don't know if i can gain anything more by really pushing the issue with rads and temps, as it was getting way late and i didn't have time for further testing.

I don't think the results are that unrealistic. I mean, i can't really be sure, but surely top speeds published in specs and tests in a controlled environment have many things going for them which not all of us have, mainly the use of proper controls and well trained test pilots that have experience in pushing the machines to their absolute limits.

I don't know if it's bugged or not, but i don't consider it unrealistic either that my 109 will be somewhat slower to one flown by a properly trained guy or someone with better controls than mine.

It's a mere 20-30km/h off and to know if the FM is in need of tuning we would first need to know if the problem really lies with the FM or just with how we work the aircraft.



Quote:
Originally Posted by klem View Post
I'm not a 109 flyer but I thought I'd drop in something Ulrich Steinhilper said in his autobiography "Spitfire on my tail". He was flying the Me109E.

He said that some of the inexperienced pilots had problems keeping up because they could not get used to the idea of establishing an airspeed with high pitch then coarsening it to get a surge in speed with a drop in rpm (a bit like connecting the energy of a rotating flywheel - the rotating engine mass) then, before the gained speed fell away with falling rpm, returning to higher pitch to maintain speed and let the revs build up again, then keep repeating the process. In this way they gained speed more quickly.

Perhaps behaving a bit like KERS in current Formula 1.

I think that technique was used for climbs mainly: rev up the engine to spool up the supercharger a bit more then go to lower RPM/coarse pitch to transfer the boost from the supercharger to a bigger "bite" of air, but the low RPM also makes the supercharger run slower so you repeat it all the way to your chosen altitude.

I do "dance" on the pitch buttons sometimes but that's mainly if i want to keep an intermediate setting between the ones that i can get by a single keypress, for example if i want to set the pitch clock to 10:50 i increase and decrease it in sequence between 10:40 and 11:00. However, that's not really something that i need to keep doing as it doesn't give any noticeable gain in final performance, it's just making the transition smoother between the two settings by letting the aircraft "settle" at an intermediate one ie, it's just a trick for a "poor man's secondary slider" to a get a bit more gradual control.
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