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ClnlSandersLite
02-04-2005, 09:17 AM
Okay, BI-1.

Out of curiosity, I decided to see how high I could get it. So:

Whole flight was done at 100% power
Duration (powered): 8.4 mins
Take off: flaps down pulled up at about 150 mph (yes, I know the diff between mph and kph)
Transit: immediate flaps/gear up stayed fairly level till nearly 200mph.
Climb: Full power 200 mph climb. I tried to maintain a constant speed, but with the BI-1's somewhat sparse instrumentation, I did have some deviation here and there.
At about 60000 feet the plane couldn't hold speed quite as well so I slowed the ascent to 150 mph. After about 70000 feet I couldn't hold that either so I just basically held what I could.

8.4 mins after takeoff I ran out of fuel at an astounding 88650 feet!
(The SR-71 hold the real record for atmosphere limited powered aircraft at 85,135 feet)

Can this result be realistic?

After VERY gently nosing down and turning around, I glided back to base and landed. Had to spiral down several thousand feet just in sight of base though.

It'd be kinda interesting to see what people can get though. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

ClnlSandersLite
02-04-2005, 09:23 AM
Oh, this was done in crimea btw.

Tooz_69GIAP
02-04-2005, 10:17 AM
Well, this is not realistic, because air density is only modelled correctly up to 10,000m (~33,000ft I think), after that, air density (and I think temperature??) is constant for as high as you can get to.

ColoradoBBQ
02-04-2005, 10:31 AM
The BI-1 has a rocket engine and would keep climbing as long as there is fuel on board. It is not an limited atmosphere powered aricraft.

Tooz_69GIAP
02-04-2005, 10:36 AM
that's true, but loss of lift would become a factor as the air thinned out. The fact is'a rocket aircraft is negated by the fact that it doesn't have the thrust to weight ratio to kep it's speed high enough for the control surfaces to maintain sufficient control.

DuxCorvan
02-04-2005, 02:11 PM
Height record for crewed rocket-powered artifacts is... the Moon. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

The only things that would prevent a BI-1 to exit atmosphere is not having fuel enough -nor enough power to lift more fuel, and life support. And yes, thin air would make you lose control, but not thrust. You would be impulsed in any direction you were aimed, without being able to correct it, unless you casually descend.

In fact, since BI-1 is anything but a presurized aircraft, you should have lost conscience before reaching that altitude, WW2 VVS oxygen masks are not enough to keep you alive up there.

taiterbud
02-04-2005, 02:21 PM
forget loosing oxygen, with out pressurization, your blood would have boiled at 63,000 ft!!! Sorry, but your dead.

darkhorizon11
02-04-2005, 02:44 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by taiterbud:
forget loosing oxygen, with out pressurization, your blood would have boiled at 63,000 ft!!! Sorry, but your dead. <HR></BLOCKQUOTE>

You can make it up to 50,000 with pressure breathing. Or another words, with an oxygen mask, but no suit. You could probably make it past 63k with no suit although even with a mask you could only have maybe two or three minutes of useful conciousness.

A rocket engine will work into outerspace as long as it has a suitable oxygen and hydrogen source (or whatever the BI-1 runs on). The problem is that the pilot controls the aircraft by asymetrically distorting airflow over the control services. With no airflow, no control.

taiterbud
02-04-2005, 02:53 PM
I wish it were that simple. You know, when U2 pilots are scheduled to make a flight above 70,000 ft. they breath 100% O2 for 60 minutes prior to takeoff just to avoid getting the bends on the way up. Conventional liquids (in other words water) biols at 63,000 ft. I've never tested the boiling point of blood, but let us not forget that your body is mostly water anyway. Basically, without a full pressure suit like what the astronauts wear, your body will simply expand in addition to all the fluids boiling. In other words, again I stress, you are dead. Breathing O2 is the least of your worries by the time you are over 63k.

ClnlSandersLite
02-04-2005, 04:19 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>air density (and I think temperature??) is constant for as high as you can get to. <HR></BLOCKQUOTE>
No, the air is most definately thinner up there, try it and see. It may be constant as in a fixed formula (exponential) that isn't correct but still thinner. If there was just a couple more mins of fuel, it would have stalled. I had to have flaps down in order to even keep the thing climbing above about 75k feet. I do Understand the death thing, I'm refering strickly to the airframe though. I must admit that I'm somewhat doubtfull.

ClnlSandersLite
02-04-2005, 04:22 PM
I also noticed a strange effect in the replay, the amount that the elevator moves in the sim (visually) is determined by it's effectiveness. Even though I had the stick fully depressed, visually, the elevator was very near to neutral.

Lewicide
02-04-2005, 04:39 PM
Using QM builder and an airstart I've made it to over 90,000 feet before loosing all aileron/rudder/elevator control and it nosing over into a lethal uncontrollable dive, compressability and disintegration. An unrealistic altitude acheived for all of the above reasons but a but of fun. Might try bailng out at 90,000 ft next time to see what happens. The longest parachute ride? http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

LEXX_Luthor
02-04-2005, 05:57 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Climb: Full power 200 mph climb.
:
8.4 mins after takeoff I ran out of fuel <HR></BLOCKQUOTE>
Real life it was more like 2 minutes. Try test flight with 25% fuel. Me~163 also should not run 8 minutes full throttle.

plumps_
02-04-2005, 06:19 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ClnlSandersLite:
Okay, BI-1.

Out of curiosity, I decided to see how high I could get it. So:

Whole flight was done at 100% power
Duration (powered): 8.4 mins
Take off: flaps down pulled up at about 150 mph (yes, I know the diff between mph and kph)
Transit: immediate flaps/gear up stayed fairly level till nearly 200mph.
Climb: Full power 200 mph climb. I tried to maintain a constant speed, but with the BI-1's somewhat sparse instrumentation, I did have some deviation here and there.
At about 60000 feet the plane couldn't hold speed quite as well so I slowed the ascent to 150 mph. After about 70000 feet I couldn't hold that either so I just basically held what I could.

8.4 mins after takeoff I ran out of fuel at an astounding 88650 feet!
(The SR-71 hold the real record for atmosphere limited powered aircraft at 85,135 feet)

Can this result be realistic?

After VERY gently nosing down and turning around, I glided back to base and landed. Had to spiral down several thousand feet just in sight of base though.

It'd be kinda interesting to see what people can get though. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif <HR></BLOCKQUOTE>

If this was meant to be a lamentation you picked the wrong plane. You should have tested the Me-163 which some people manged to take to 50.000 (?) m.

But on the other hand, as several other members of the forums have already reported this in the past it's old news. It's known and and it can easily be avoided by simply not climbing too high. We can live with it the way we live with some more limits of the IL-2 engine. Especially since we know that Oleg's team is working on a new engine that will address many of the known issues that will not be changed in the current engine. And as most of us are no masochists we won't mention the known issues every day; instead we will concentrate on the many aspects of this sim that are pure fun.

ClnlSandersLite
02-05-2005, 03:14 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>If this was meant to be a lamentation you picked the wrong plane. You should have tested the Me-163 which some people manged to take to 50.000 (?) m. <HR></BLOCKQUOTE>

Not really a "lamentation", just something interesting. I hadn't seen the topic before so I didn't know if very many people knew about it. I'm going to have to try the Me-163 now, I also might try the parachute dive that Lewicide mentioned. I'm curious to see just how long that will take http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif.

cwojackson
02-05-2005, 03:40 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ClnlSandersLite:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>If this was meant to be a lamentation you picked the wrong plane. You should have tested the Me-163 which some people manged to take to 50.000 (?) m. <HR></BLOCKQUOTE>

Not really a "lamentation", just something interesting. I hadn't seen the topic before so I didn't know if very many people knew about it. I'm going to have to try the Me-163 now, I also might try the parachute dive that Lewicide mentioned. I'm curious to see just how long that will take http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif. <HR></BLOCKQUOTE>I'd request a video of your chute ride but I have a feeling it would/will be longer then a PF campaign mission. If you do try it however, I'd be interested in whether the pilot survives or not.

Asgeir_Strips
02-06-2005, 04:52 AM
I dont think a person without a pressure suit would survive over 60.000ft. But i read somewhere that a F16 Service ceiling was 50.000ft and the F16 pilots doesn't wear pressure suits, (Allthough, modern oxy-systems is far more complex than 60 yrs. ago..) But i think its realistic to survive in 50.000-55.000 ft without a pressure suit.. (Allthough the F16 cockpit is pressurized :-P ) http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif