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billclarke1
09-27-2004, 12:53 AM
When flying Me262 at more than 7500m, I find the aircraft has terrible handling characteristics, is this a consequence of the reduced oxygen level ? This is also apparantly also the case with other piston engined aircraft.

billclarke1
09-27-2004, 12:53 AM
When flying Me262 at more than 7500m, I find the aircraft has terrible handling characteristics, is this a consequence of the reduced oxygen level ? This is also apparantly also the case with other piston engined aircraft.

jurinko
09-27-2004, 02:29 AM
at high alt the air density is much lower and depending on the engine its output may also decrease. But whether the high alt modelling is 100% exact in FB for each A/C I can´t say.

Bearcat99
09-27-2004, 07:34 AM
From what I understand the high alt modelling is not 100% but it has indeed improved greatly from what it was in the original IL2. In fACT I have a high alt P-47 QM that I practice with and I must say... if you fly it right it is a different plane up high. I think the high alt FMs are much much better. You just have to think keep the speed up... you have to think more on the diagonal than the horizontal or vertical...... I find that the damage effects are different up high too.... very often if you pop a inline engine with a good burst of 50 cals.. and depending on your convergence and your distance a 2 second burst is more than enough to do the job..... the engine of the target will sometimes over rev and if there is a fuel leak the plane will explode.. or once it starts down often it will explode before it hits the ground because the engine has overreved so much. It took me about 2 weeks though to finally begin to get he handling right and it was after the last patch with the fixed 50s that I was fially able to actuall survive this mission (sometimes http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif) 4 P-47D-10s & 4P-51D20s all on average or vet with 1 AI Ace... (Im the other Ace... http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif) sometimes I throw in a rookie but the AI is tough enough.. escorting 8 B-17s against 8 109G-6s and 4 190 A-8s and 4 190 A-5s. Sometimes to make it a but more surviveable I take one plane from each of the German flights making it a 12 vs 8 matchup... It is very difficult to survive the 8 vs 16 matchup. The German AI are set up with 2 Aces, 8 vets,4 average and 2 rookies. I like to mix up the AI... to me that is more realistic. Throwing in the rookies kind of allows for the pilots who were either not that as good, scared, fatigued or whatever.
The mission is at 7500m it usually winds up going down low.. I am working on a Coop that I will try to make so it stays up high though...

WWMaxGunz
09-27-2004, 09:35 AM
Altitude aboves 10km all act the same.

What IAS are you flying the 262 at? If you are flying TAS in no-cockpit then you will
see a much larger number than IAS which is a better measure of how your handling should
be.


Neal

clint-ruin
09-27-2004, 09:43 AM
One thing to bear in mind is that the QMB starts aircraft off at around 300kmh TAS, regardless of altitude. If you put a jet with fairly ordinary acceleration stats at 10km instantly, it is not totally surprising to see that it needs to drop a fair bit of alt to pick up sufficient speed to stay up there. No idea if it was really as severe as it is in FB though.

k5054
09-27-2004, 11:09 AM
The handling ought to depend on the IAS, not the altitude itself, but various acceleration and inertia effects depend on true speed.

Hint for imperial measure fans, at 29,000ft (9km ish) your IAS in km/h is equal to your TAS in mph.

At that height your 262 is working in air about 40% as dense as at SL. Jet engines like the Jumo 004 have thrust which varies with density. So they are on 40% of SL thrust. So at 300mph (true) your 262 has only 1600lb thrust whereas it took off with 4,000 lb. With a weight of say 12,000lb it can't do much in the way of climbing. It's like it was a prop plane with the weight of a P-47 and only 1600hp. At less than 300mph it gets worse, thrust is the same but the equivalent HP gets worse. Conversely as it gets faster the equivalent HP gets better. At 450mph it has 2400hp net where a prop plane would need over 3000hp to have the same thrust. Jets up high must go fast to generate excess power for climbs and turns. If you go slow it all deteriorates. If you get slow you have to dive to get your speed back, it's no good flying leveel and hoping to accelerate quickly.

Bull_dog_
09-27-2004, 06:58 PM
All planes handle differently at altitude...some better than others....the spit and P-47 are wonderful up high while others like the Lightning turn into pigs up high as they lose their lift and won't turn or climb without added trim input. I don't fly the 262 so I don't know if this is what you are talking about.

I know it is just differences in Fm's but what I don't know is if it is intentional or just a mistuned FM waiting further refinement.

billclarke1
09-27-2004, 07:54 PM
The main problem for me is the nose won't stay up, and turns are shocking, speed wise.
What is with the trim adjustments ?
How did these A?C fair historically ? as I know the B17's flew in at 30,000 ft.

WWMaxGunz
09-27-2004, 10:34 PM
Historically they flew fast at those alts, very fast.
You don't say what kind of speed or even what measure (IAS/TAS)
where you see these problems.


Neal

WUAF_Badsight
09-27-2004, 11:37 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by k5054:
The handling ought to depend on the IAS, not the altitude itself, but various acceleration and inertia effects depend on true speed.

Hint for imperial measure fans, at 29,000ft (9km ish) your IAS in km/h is equal to your TAS in mph.

At that height your 262 is working in air about 40% as dense as at SL. Jet engines like the Jumo 004 have thrust which varies with density. So they are on 40% of SL thrust. So at 300mph (true) your 262 has only 1600lb thrust whereas it took off with 4,000 lb. With a weight of say 12,000lb it can't do much in the way of climbing. It's like it was a prop plane with the weight of a P-47 and only 1600hp. At less than 300mph it gets worse, thrust is the same but the equivalent HP gets worse. Conversely as it gets faster the equivalent HP gets better. At 450mph it has 2400hp net where a prop plane would need over 3000hp to have the same thrust. Jets up high must go fast to generate excess power for climbs and turns. If you go slow it all deteriorates. If you get slow you have to dive to get your speed back, it's no good flying leveel and hoping to accelerate quickly. <HR></BLOCKQUOTE>

this is as good a explanation as your going to get

the service ceiling wasnt that high for the Schwalb , was 10,500 or 11,500 9cant remember which

plenty of propeller planes are capable of more (even the Zero)

starting at 300 TAS at 10K is only a puny IAS , try using the FMB & setting your speed to like 700

i know that at 7k it just dies & doesnt want to climb anymore at all

WUAF_Badsight
09-27-2004, 11:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by billclarke1:
When flying Me262 at more than 7500m, I find the aircraft has terrible handling characteristics, is this a consequence of the reduced oxygen level ? This is also apparantly also the case with other piston engined aircraft. <HR></BLOCKQUOTE>

its because of its low power output at those alts

it dont have enough power to maintain speed very well at 7K & above . . . . . . your a sitting duck over 7K in a 262 as it wont climb for beans

to be able to defend yourself up their you must maintain as much speed as possible

clint-ruin
09-28-2004, 12:41 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by WUAF_Badsight:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by billclarke1:
When flying Me262 at more than 7500m, I find the aircraft has terrible handling characteristics, is this a consequence of the reduced oxygen level ? This is also apparantly also the case with other piston engined aircraft. <HR></BLOCKQUOTE>

its because of its low power output at those alts

it dont have enough power to maintain speed very well at 7K & above . . . . . . your a sitting duck over 7K in a 262 as it wont climb for beans

to be able to defend yourself up their you must maintain as much speed as possible <HR></BLOCKQUOTE>

One thing to bear in mind is that 'fast' in the jets really means 'very fast' - much faster than what people think of as fast for a prop. The La-7 and Ta-152 cap out somewhere around 680kmh at altitude. That's straight out, balls to the wall, accelerate for a while speed. The jets don't appear in Il2compare, but just from experience - if you cannot get your speed to around 900kmh TAS from a shallow dive quickly in your jet, you are too slow. You want to always be at 600-700kmh+, never slower, ever. If you have to take big circles to turn, or just let the lift of your wings turn you from a slight roll - do so. The target prop plane will not be going anywhere fast - you will disappear from his view very soon at that speed and can come back to the area whenever you want. Fuel isn't -that- terribly short in any of the jets, though the rockets are a big brief.

The other thing to remember with FBs jets is that they will never overheat. "What?!" you say, monocle popping out and shattering on your desk - "Poppycock!" - but it's true. I am sure everyone has seen the overheat warning come up as they accelerate from qmb start/takeoff. If you leave you engines at 100% all the way to your top speed, yup, you might fry them eventually. Don't do that. Set the throttle to 70-75%, and fly level until you are as fast as you seem to be able to go at that throttle setting. Then power up [slowly] to 100% - your final burst of speed will make you go so fast that you sort of outrun your own overheating. When I was last testing it [2.01/2.xb5], not one single jet in the game would overheat at its top speed, once it got there. And you can stay that fast until the fuel runs out. The P-80/He-162 top out at somewhere around 800kmh+ in level flight at sea level, would have to look back at the results to be sure though. That is seriously fast. That is 100kmh over what any prop in the game will do for you even at its ideal altitude, not in the weeds.

Personally I am most attached to the strap-on Me-262A1U4 model - the 50mm is much more effective for very high speed combat than the minethrowers. And it always makes me think of that FW200 thread where that nutty guy went crazy at me and makes me laugh.

WOLFMondo
09-28-2004, 06:25 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Bull_dog_:
All planes handle differently at altitude...some better than others....the spit and P-47 are wonderful up high while others like the Lightning turn into pigs up high as they lose their lift and won't turn or climb without added trim input. I don't fly the 262 so I don't know if this is what you are talking about.
<HR></BLOCKQUOTE>

I fly them very occasionally and don't really like them up high because of there need for uber energy to get anywhere but I find it more satisfying as bouncing them at 500mph in a P47http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

geetarman
09-28-2004, 10:20 AM
Slightly OT - wasn't the Lightening suppose to have very good performance up high? In the game the P-47 does, not the Lightning.