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michapma
02-06-2004, 05:54 AM
Since I have "grown up" as a child of IL-2, I have little virtual (or real, of course) experience and little knowledge gathered about aircraft handling at high altitude. Oleg has stated that the high-alt flight model is not accurate, that it hasn't priority since the Eastern Front was fought at low to mid alt. Of course there is regardless no end of people who will be willing to gripe about how it isn't modeled properly. That's not what I care about.

What does interest me is learning about how aircraft really should handle up there. Last night I took the Me 262 and the FW 190 A8 up at 10000m and 7500m against B-17s in the QMB. Unfortunately start speed is something around 180 IAS, so the first thing to do is dive for speed and then try to climb back up to the bombers' level. In both aircraft, I found it extremely difficult to maintain speed and to maneuver. I also think I discovered that in the 262 airspeed indicator, the white needle is IAS and the yellow needle a calculation of TAS...

Even just climbing above the bombers was a tremendous exercise in patience. Now I know that B-17s are good high-alt aircraft, and again I know that the flight model is off at these alts, but how should it be? Should it really be so laborious to climb, much less turn? When we say that the 190s, P-51s, P-47s et al. rule at high altitude, do we mean that they can do anything except dive, or should they handle as easily at 10000m as the low-alt aircraft do at 1000m?

What is off with the high-alt characteristics? The handling? The climb rates? The airspeed?

Informed responses especially welcome... http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

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michapma
02-06-2004, 05:54 AM
Since I have "grown up" as a child of IL-2, I have little virtual (or real, of course) experience and little knowledge gathered about aircraft handling at high altitude. Oleg has stated that the high-alt flight model is not accurate, that it hasn't priority since the Eastern Front was fought at low to mid alt. Of course there is regardless no end of people who will be willing to gripe about how it isn't modeled properly. That's not what I care about.

What does interest me is learning about how aircraft really should handle up there. Last night I took the Me 262 and the FW 190 A8 up at 10000m and 7500m against B-17s in the QMB. Unfortunately start speed is something around 180 IAS, so the first thing to do is dive for speed and then try to climb back up to the bombers' level. In both aircraft, I found it extremely difficult to maintain speed and to maneuver. I also think I discovered that in the 262 airspeed indicator, the white needle is IAS and the yellow needle a calculation of TAS...

Even just climbing above the bombers was a tremendous exercise in patience. Now I know that B-17s are good high-alt aircraft, and again I know that the flight model is off at these alts, but how should it be? Should it really be so laborious to climb, much less turn? When we say that the 190s, P-51s, P-47s et al. rule at high altitude, do we mean that they can do anything except dive, or should they handle as easily at 10000m as the low-alt aircraft do at 1000m?

What is off with the high-alt characteristics? The handling? The climb rates? The airspeed?

Informed responses especially welcome... http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

http://www.baseclass.modulweb.dk/69giap/fileadmin/Image_Archive/badges/69giap_badge_chap.jpg (http://giap.webhop.info)

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Blutarski2004
02-06-2004, 08:58 AM
I cannot speak to the exact manner in which FB high-altitude modelling is deficient. But the real world situation is basically as follows-

The basic controlling factor of a/c performance versus altitude is the "critical altitude" of its engine/supercharger powerplant package. In simple terms, critical altitude marks the highest altitude at which the powerplant can more or less produce its maximum power. As altitude increases above this critical altitude, engine output steadily decreases. When the engine output has fallen to the point where it can just barely keep the a/c in the air, that is the ceiling, or maximum altitude, achievable by the a/c.

High speed and maneuvers such as sustained climbs and turns require the availability of excess engine power in order to be performed. As a consequence of the above-mentioned progressive loss of power versus altitude, less and less excess power is available as altitude increases above critical. At their ceiling, a/c have very little or no excess power available. Therefore the possibility of maneuver likewise becomes progressively more difficult.

BLUTARSKI

[This message was edited by Blutarski2004 on Fri February 06 2004 at 10:54 AM.]

LEXX_Luthor
02-06-2004, 09:58 AM
Well as power goes down, and so does the amount of air the plane's wings and control surfaces can grab onto at a given TAS, so its a double Whammy. They say on the webboards that if you keep your IAS up, everything is the same but...

...For a given IAS, the TAS is higher at high altitude, and the faster you go the larger the turning circle for a given turning force. So things are not the same. I bet if you pull back the stick the same amount at sea level and high level, at the same IAS, you black out earlier at high level cos your TAS is larger way up there...and other aerodynamic affects too maybe like I'm thinking the air over the wing gets more "stally" at high level at a given IAS. That P~51B dude wrote about the dozens of Fb109s at over 10km that turned into them and the Fb109s all fell out of control.



__________________
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Blutarski2004
02-06-2004, 10:30 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by LEXX_Luthor:. That P~51B dude wrote about the dozens of Fb109s at over 10km that turned into them and the Fb109s all fell out of control.<HR></BLOCKQUOTE>


...... Expect to receive soon a very uhappy reply from Emperor Huckebein of the Messershmitts.

;-]

BLUTARSKI

LEXX_Luthor
02-06-2004, 10:37 AM
*bah* I am still struggling with Mach 2 Yak~28P maximum speed. If Huckebein is (choke) right, then I owe him/her a huge debt for opening my eyes. I still don't Believe it though. Religion. So far in the scriptures I have seen, I still can't find any scriptural reference to Yak~28 having Area Rule.



__________________
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Stanly is a moron, kai is a walking dead beet, Xev just want sex.
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p1ngu666
02-06-2004, 10:41 AM
blu makes a good point
the p40 was dire at high alt, didnt have a supercharger for it
now the p47 did. well a turbo http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif
hopefully the high alt will be fixed in the add on. cos of spit, p38, go jobby, ta152, p80, 163
if they didnt, u gotta wonder why the chose the high alt ta152 over the low alt one. that may not have flown tho :\

JorBR
02-06-2004, 11:35 AM
Post by Oleg Maddox 29-01-04 02:34

http://forums.ubi.com/eve/forums?a=tpc&s=400102&f=63110913&m=712109571

â˜Dear user,

FM is comlex thing... Aerodynamics behaviour of the plane changes with altitude very much. At high altitude the air dencity is way lower than on close to sea level altitudes. So the plane should be controlled very gentle comparing to low altitudes. Say turn times became much greater, maneuverability became much worse, etc... The stalls and spins will be more dangereous than on SL... Much more dangerous! And climb rate will be zero at maximal rated altitude for the given aircraft... You can ask it all real pilots, that will confirm that we model physics of that law very correct. There are more than 40 real pilots in our internal tests...

Really its not FM, its a laws of the physics.
Its why was better the prop planes with long wings at altitude - Ta-152, various of MiG's design aircraft(not serial), some of projected 109s modifications, etc for example

Some planes that were able to fly at 10 km and higher altitude duet to good superchargers were almost uncontrolable in terms of maneuverability on these altitudes. High speed of the plane doesn't means good maneuverability on high altitudes automatically. For good and situable maneuverability were designed very special aircraft (see above). From that point of view we model it very correct, simply becasue we model that physics of low air dencity at these altitudes.

Also in IL-2 and FB 3D world we model the changes of air dencity only till 10 km altitude. Higher it is constant due to limit of that engine. Its becaseu in original project were not planned any of coming later aircraft. But trust me there were not any real battles at altitudes higher than 10 km....
The new 3D physics world will be done only in the completely new sim. There will will not limit that world by 10 km altitude.

Speaking above, please try to read the descriptions of WWII pilots about where was beginning the dogfight(means Fighter vs Fighter) and where it was finished in terms of altitudes... Right, beginning on high and ended on low... Why do you think?
(you can read it with little attention in almost every recalls of German and Alies pilots for example.... Just apply for these recals the laws of physics)"

"Never wrestle with a pig; you both get dirty but the pig enjoys it!"

EldOVed
02-06-2004, 11:44 AM
Well 5000m seems to be the "critical altitude" for the La5. I was on gratergreen and saw a 109 buzzing around over my head so I went up to engage him. He was about 5400m. It was funny, every time I got to 4950m I just started to drop. Like a force feild that I couldn't penatrate. No way I could get over 5000m. Then it hit me. "The La5 has no more balls."

JorBR
02-06-2004, 11:48 AM
EldOVed, do you enabled CEM? It never happened to me with CEM disabled.

F19_Olli72
02-06-2004, 11:59 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by EldOVed:
Well 5000m seems to be the "critical altitude" for the La5. I was on gratergreen and saw a 109 buzzing around over my head so I went up to engage him. He was about 5400m. It was funny, every time I got to 4950m I just started to drop. Like a force feild that I couldn't penatrate. No way I could get over 5000m. Then it hit me. "The La5 has no more balls."<HR></BLOCKQUOTE>
To me it sounds as if you didnt adjust your fuelmix. Service ceiling for La-5 is 10 650 m (according to FBs "object viewer").

XyZspineZyX
02-06-2004, 12:05 PM
The simpler explanation is,

At high alts, planes tend to "wallow" more. Climbing is very difficult and slow, it's harder even to keep level bank, and the plane keeps "wanting" to stall, or go nose low and dive to where it can get more "bite" from the prop and the wings.

Turn radii increase dramatically because banking can cause spins much more readily, so you have to be much gentler while turning. (see above).

The only thing that seems "easier" for the plane to do at "nosebleed" alts is to dive. You'll enter a shallow dive and find you've dropped 2 or 3 km like that. Then, of course, it's a long, arduous adventure trying to claw up and get that alt back.

Now, depending on your plane, the alt at which these effects become problematic is different. A 109 would feel this effect begin at 8-9km or so, while a FW190 might start feeling it at 6 or 7km. A P-47 would likely not feel this effect much before 9-10km (but then, it doesn't turn well down low, so it's less noticeable). In fact, you can see from this why the P-47 was so good at its bomber escort role: it was "maneuverable" (for a P47) where other planes were wallowing and gasping for the thicker air below. And it loved to dive, which is the easiest thing to do at that alt anyway.

LEXX_Luthor
02-06-2004, 12:05 PM
Yep, goto External View and see if you are belching brown smoke. Reduce Mix just enough so you stop smoking. Failure to adjust Mix properly severely cripples planes at high altitude. Also, watch your engine instruments when you change Mix at high altitude and you can learn to change Mix without looking at External View...

...or use External View and brown smoke and make a small data table of when you should change fuel Mix at various altitudes. If you fly a plane often enough, you will know this table well.



__________________
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:
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XyZspineZyX
02-06-2004, 12:11 PM
Lexx wrote:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Yep, go to External View and see if you are belching brown smoke<HR></BLOCKQUOTE>

And, if you're on a server that doesn't allow such a crutch? Then what? http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

EldOVed
02-06-2004, 12:16 PM
mmmm... fule mixture, that could be it? I thought it was weird, the 109 was just crusing no problem. Never thought about fule mix. Usually don't fly over 4K. Also I might have had a few holes in my wing (reduced lift). I got lightly sprayed on the way.

F19_Olli72
02-06-2004, 12:36 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Stiglr:
Lexx wrote:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Yep, go to External View and see if you are belching brown smoke<HR></BLOCKQUOTE>

And, if you're on a server that doesn't allow such a crutch? Then what? http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif<HR></BLOCKQUOTE>
Not a problem, just listen to the engine....if it sounds like a dying lawnmover engine it has got the wrong mix. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

michapma
02-06-2004, 12:56 PM
JorBR, I thank you very much for posting that. I should go to the ORR more often.

I knew about engine power, I've been reading up on superchargers, but I was unsure about flight characteristics. Seems to reflect what I experienced quite nicely. So the FW 190 starts faltering already around 6 or 7 km? I can believe that, but the A-9's ceiling is cited as 11,400m at the IL-2 site. Those B-17s seemed not to mind much! It was far easier to climb above them of course down at 4000 and 5000 m. The Me-262 had a lot of trouble at 7500 and 10000 m too; it's ceiling is shown as 11500 m. I'll have to try the Dora, even though its service ceiling is pegged at 11000 m, and the Kurfurst, with 12000 m. It was easy to reach these TAS values of up to over 600 kph, but maneuver? With extreme patience. It's clear that I was ham-fisting the controls, way too much backpressure. I got better results by making slight adjustments with the trim.

Stiglr, I've read that you can use the exhaust gas temperature (EGT) gauge to lean the mixture. In FB I don't think we have that, but you can go by the manifold pressure (MP) gauge. Adjust the mixture so that the MP is maximum. If it doesn't make a difference, it is probably not critical. At constant engine speed, MP can be a good measure of output power. Note that you can overlean your engine to save fuel, I do this on long missions in the Yak-1. It was probably very bad for the sparkplugs, but I don't think we pay those kinds of penalties.

Thanks for the discussion everyone, I love learning new stuff, especially when I can go apply it. http://ubbxforums.ubi.com/images/smiley/icon_twisted.gif

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LEXX_Luthor
02-06-2004, 01:20 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>And, if you're on a server that doesn't allow such a crutch? Then what?<HR></BLOCKQUOTE>
You can use External View offwhine to make an altitdude data table for proper fuel mix and if you fly a plane more than once, you should be able to learn that table for that plane.



__________________
RUSSIAN lexx website http://www.lexx.ufo.ru/members.shtml
Stanly is a moron, kai is a walking dead beet, Xev just want sex.
:
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p1ngu666
02-06-2004, 01:22 PM
on full real look back, and yaw the plane. in most u can see behind then, and ull see the brown trails
dont forget stage 2 supercharger

chris455
02-06-2004, 01:39 PM
VERY well written response Blutarski.

If what you wrote is described as "maximum ceiling" then would "service ceiling" be the maximum altitude at which the plane could be expected to perform combat maneuvers? I'm just guessing-
S!

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Rata18
02-06-2004, 02:03 PM
Service ceiling: The altitude at which the rate of climb drops below a nominal value.
I can't remember the actual values used, but 100 fpm rings a bell? - It still doesn't really allow for combat manouevers, but most examples of the aircraft *should* be able to get there...
...eventually.

MiloMorai
02-06-2004, 02:06 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Stiglr:
Lexx wrote:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Yep, go to External View and see if you are belching brown smoke<HR></BLOCKQUOTE>

And, if you're on a server that doesn't allow such a crutch? Then what? http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif<HR></BLOCKQUOTE>


There is always off-line to do the testing.http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif http://ubbxforums.ubi.com/infopop/emoticons/icon_razz.gif



Long live the Horse Clans.

robban75
02-06-2004, 02:12 PM
The Fw 190D-9 will suffer at altitudes above 7000m. The D-9 really wasn't a high altitude fighter. At 10,000m it could manage 639km/h, whereas the D-12(the true high alt version of the D family) was 100km/h faster at that altitude.

http://members.chello.se/unni/Dora-9-3.JPG

When it comes to aircombat, I'd rather be lucky than good any day!

BfHeFwMe
02-06-2004, 02:47 PM
Two things I notice missing is the temperature drop and the AOA seems off also. Taking an aircraft that high your oil and water temps should hit the lower end of their thermostatic regulation in a sustained cruise.

In game there's no difference at all for any altitude, unable to ever bank cooling effects, that's not correct. We used to routinely force the oil coolers open right at descent on hot days from cooler altitudes. You could buy yourself a good twenty minutes extra for ground operations by keeping the oil cool through the let down.

The bombers with heavy loads and that high should be riding with excessive AOA, even getting near the service ceiling. Throwing even mild aileron they would drop away, very delicate balancing act with strict limits. Most heavies are equipped with aids such as YAW dampers and control reducers. No way should they be moving like they do in game with dodging manouvers, that would result in catastrophic departure. Might be one of the reasons everything can move so fast and clean, no high AoA, not as much drag.

You get near service ceiling and you should be hanging on the props, my pilots usually adjusted the ADI waterline going high. That's how much they pitch up, the horizon is no longer even close on the indicator.

michapma
02-06-2004, 03:40 PM
Thanks BfHeFwMe (I can remember the initials, but not the order http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif),

That explains a bit more, very good info. That also helps me understand that the bombers wouldn't maneuver like that, which I indeed suspected. What was a typical cruise altitude for the B-17s? Wasn't it something like 20-30,000ft?

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BfHeFwMe
02-06-2004, 05:15 PM
I don't know about the B-17's, but a loaded down Herk is going to struggle to reach 30,000, and they have much better power and wings. Near empty I've been up to 34,000, can tell you if you tripped in the back you'd roll all the way till you hit the rear door. Thats how much it hangs on the prop. IAS is way down, but your true is cooking pretty good. You could see the blade angles were pretty course, max or near, takes much of the power just to hang there. Pretty much flying with the trim wheels and auto pilot at or near service ceiling altitudes.

Used to go up to 40 to 45,000 cruise on Starlizards, that was normal cruise even fully loaded. They could cruise much higher but you'd need pressure suits. You'll notice the ones designed for high altitude cruise always look awkward in angles when landing or taking off, like the nose is down to far. Wings are set at a different angle to fuselodge relation. Only have to watch a B-52 take off to see the effect.

Blottogg
02-06-2004, 08:39 PM
JorBR, thanks for the reprint. I had thought the problem was with temperature modeling. Turns out its density. That also explains the climbs to the moon some folks do with the rocket and unlimited fuel.

Think of it this way. The only thing the airplane cares about is IAS (indicated airspeed.) We'll ignore compressibility and Mach effects, since they're not modeled anyway. The plane will "handle" the same at 10,000m or 10m if flying at the same IAS. It's power available will be different, but for instantaneous maneuvers, its handling will be identical. Up at 10,000m the airplanes manage lower max IAS (due to less power available), and so "wallow" like Stiglr mentions, as they should. As it currently stands though, the model doesn't sufficiently handicap aircraft without compound superchargers, or long, high aspect ratio wings (yes, it's supposed to be even worse for most planes at these altitudes.) In other words, the P-47 can't really shine compared to other aircraft in the sim, because its engine advantage is to some extent shared by all aircraft at altitudes above 10,000m. The same will no doubt be true for the P-38 and Ta-152 when they arrive.

BfHeFwMe excellent points. I think the problems you mention may be with the CEM modeling, and not just the atmosphere model. As far as other aircraft go in the sim, I think this is another area where the Ai's "simplified" flight model stands out, especially with regards to energetic bomber maneuvering. BTW, I didn't know the C-141's would get that high, though with the low bypass TF-33's it makes sense. Were all those altitude restrictions due to cockpit window cracking just politics for the C-17, or was it due to those high altitude forays?

Blotto

"Speed is life." - Anon
"Sight is life. Speed is merely groovy." - "Junior"

Dav_1
02-06-2004, 09:24 PM
Jeez, wonder how I feel? In the first IL2 aircraft don't reach the speeds they're supposed to at ANY altitude!

example: Bf109G6 (oh hell ANY 109!) Fw190 blah blah

Why can't I ever reach the 600km/h speed that 109G6 is supposed to fly at? Combat at 200-300km/h speeds is pitiful

michapma
02-07-2004, 01:54 PM
Dav_1, these speeds are in many cases reachable, but not instantaneously. It takes a while for them to accelerate to full speed, and the closer they get, the longer it takes. The K4 for example does 580kph at sea level, just like it's supposed to. Recall that these speeds are TAS, true airspeed, not IAS, indicated airspeed. The G-6 is supposed to do 530kph at sea level, where TAS and IAS are pretty close. At 7000m, the G-6 should do 640kph TAS, which is going to be much, much lower in IAS. I don't mean to imply you don't know how to fly of course, but if you can't get above 300 at say 2000m, you're doing something wrong.

So what do you mean? Can you give specific examples?

If you're seriously fighting at 200-300kph

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BfHeFwMe
02-07-2004, 02:55 PM
The 45K ceiling was solely due to human physiological limits. Above that regulations required a pressure suit. I know the bomber guys went higher than that, and without suits, but those guys are normally attached to O2 the whole time, and get a good nitrogen purge.

mortoma
02-07-2004, 05:37 PM
Yes I think the HA model in FB is porked and yes Oleg does acknowledge it. All the posts in here about planes not flying as well up high as down low is for sure right. But, the Me262 historically performed extremely well at the typical B-17 and B-24 bombing altitudes. So well in fact, they could climb up way above the bombers and dive down on them and then go back up through the formations
in a high energy climb, which is when most fights of 262s would fire at the bombers. In FB, you can't even do anything but barely maintain your altitude, you just wallow around pathetically. So some of you guys are right about less performance, but in the 262s case, it still was able to manuever like a screaming banshee. This is a historical fact. I am looking for sources now. But I know I have read about them tearing around at high altitude, blowing bombers to bits, as if they were at middle or even low altitude in FB.........

Dav_1
02-07-2004, 08:38 PM
I don't know what to say michapma,
I pick something like the Bf-109G6 late, choose 7500 meters in the QMB, follow all the rules to get speed (throttle 100%, emergency power on, prop pitch full) and fly level and my indicated airspeed rarely goes over 300kmh.

What could I be doing wrong?

(oh yeah and i forgot, i tried doing the same scenario in FMB where i setup just a little bit of fuel and no ammunition and i got the same results)

Cajun76
02-07-2004, 10:29 PM
Dav_1, add this to your test next time. Do the same thing, and make sure you have speedbar enabled. Then switch to No Cockpit view. Viola! TAS and IAS, for your viewing pleasure. Get used to the conversion difference, and you won't need No Cockpit, if that's your desire.


As far as a temperature difference at high altitude, there is one in my experience. The best example is how I manage my engine on the P-47 on a scripted, rotating map server.

Server 1: Winter Map. I can fly around all day at WEP without overheating, and not using my cowl flaps, any altitude.

Server 2: Summer Map. My typical claw for altitude, full WEP, rad open, overheat in 5 minutes or so. Keep climbing, depending on enemies, throttle back. Cool off, WEP on, climb until overheat. By about 5000m, the overheat will go off, and stay off as long as I'm high. Full WEP, rad closed at 9000m no problem. Same server, down low, will overheat with rad open and WEP on again.

So there seems to be some variation, maybe not as much as real life, or as much variation, but some.

Good hunting,
Cajun76

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michapma
02-10-2004, 02:03 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Dav_1:
I don't know what to say michapma,
I pick something like the Bf-109G6 late, choose 7500 meters in the QMB, follow all the rules to get speed (throttle 100%, emergency power on, prop pitch full) and fly level and my indicated airspeed rarely goes over 300kmh.

What could I be doing wrong?

(oh yeah and i forgot, i tried doing the same scenario in FMB where i setup just a little bit of fuel and no ammunition and i got the same results)<HR></BLOCKQUOTE>

The charts at il2sturmovik.com say the G-6 should do 640 kph at 7000 m. As Cajun points out, that's in true airspeed, not indicated airspeed. If you look on the second FB CD, in the folder "MANUAL" you will find a PDF file with a table for conversion between TAS and IAS. According to that table, at 7000 m 657 kph TAS corresponds to 450 kph IAS. That's still a big gap to what you indicated you can get, around 300 kph IAS, which is only 438 kph TAS according to the chart (or 448 kph TAS for 7500 m).

That's interesting, I think I'll try and remember to test out the G-6 at those alts. 100% fuel and keep the plane very steady... remember, we're talking top possible speed, so I won't be disappointed if I get a bit less, as I'm no test pilot. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

http://www.baseclass.modulweb.dk/69giap/fileadmin/Image_Archive/badges/69giap_badge_chap.jpg (http://giap.webhop.info)

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