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1 hour ago, ZachariasX said:

You‘re not that lucky. Sorry to say that.

 

Compressor stalls that you would more likely have on two or three spool jet engines. In a single spool jet engine, you‘d supply too much fuel by opening the throttle too fast. This excess of fuel creates a larger burn (there‘s still enough of air to burn that fuel) and this increases temps beyond permissible limits.

 

So if you are advancing throttles way faster than the engines are spooling up, you should indeed expect a little fire eventually. But more interesting will be how the compressor out there next to you will come apart (and in which direction).

 

Trust me, slamming the throttle forward in such a jet is more entertaining than you described it.

 

I too think horsing around with one of those early jets was much more hazardous than @LuseKofte mentions, and there is data to support that. But be it more or less frequent, or more or less spectacular in its results, the fact is, in order to operate the 262 similarly to historical parameters, we must have a good dose of engine unreliability.

 

If we are allowed to simply move the throttle up and down like crazy, the 262 will soon be used mostly in situations totally unnaccording to historical facts. For instance, dogfighting the P51 (or trying to). If we go there, we might as well have the p80 or the Gloster Meteor added eventually to a "great hipothetical battles" series (which wouldnt be bad, perhaps!) to have 262s x p80s dueling in fantasy scenarios.

 

Hum ..... Come to think of it, that would be AWESOME hehe. 

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Yes I read earlier they actually did burst into fire. And infact I stated so in this forum. But got shot down here saying this and one of them whom said it only would flame out. Was referring to a interview.  The fact that there will be air enough to supply any amount of fuel to a fire hazard mix seems very likely to me. And I stay corrected

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Posted (edited)

I hope they model the engine temperament but I'm not sure they will go into much detail or they may just keep in simplified like the P-47 Turbosupercharger.

Edited by Legioneod

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Well the slow acceleration and careful throttle settings should be implemented. The plane is known for that. I think A German pilot serving in Argentina said something like he would have loved seeing the 262 with Meteor engines

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52 minutes ago, Legioneod said:

I hope they model the engine temperament but I'm not sure they will go into much detail or they may just keep in simplified like the P-47 Turbosupercharger.

 

I too think we will be getting a damage system much more suave than the real thing. Well, at least it will be something. What would be unberable would be to horse around with the throttle without consequence.

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Posted (edited)
21 minutes ago, danielprates said:

 

I too think we will be getting a damage system much more suave than the real thing. Well, at least it will be something. What would be unberable would be to horse around with the throttle without consequence.

Leaving out the quirks you might as well fly war thunder. I am not against this plane. I like it to perform as it did. And that means do not loose speed. Never mind the throttle management it accelerated very slow so you simply avoid bleeding speed and you spend all your ammo in fewest amount of passes. It did not have  fuel capacity for long flights

Edited by LuseKofte

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Posted (edited)
45 minutes ago, LuseKofte said:

Leaving out the quirks you might as well fly war thunder. I am not against this plane. I like it to perform as it did. And that means do not loose speed. Never mind the throttle management it accelerated very slow so you simply avoid bleeding speed and you spend all your ammo in fewest amount of passes. It did not have  fuel capacity for long flights

 

Agreed. I would like to see it as real as possible. But at the same time, I understand the developers have limited resources and honestly I would be satisfied with 'some' degree of engine management realism.  To me, it would suffice if it was made in such a way that the pilot couldn't fiddle haphazardly with the throttle without consequence. That would be enough. IIRC il21946 made it so that if you changed the throttle too fast, the engine could catch fire (and frequently would). That would already be enough imho. 

 

It bet that in the time and effort it takes to model those engines to absolute perfection, half a Mosquito could be modelled.

Edited by danielprates

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12 hours ago, ZachariasX said:

Compressor stalls that you would more likely have on two or three spool jet engines. In a single spool jet engine, you‘d supply too much fuel by opening the throttle too fast. This excess of fuel creates a larger burn (there‘s still enough of air to burn that fuel) and this increases temps beyond permissible limits.

 

It's true that single spool engines are more resistant to compressor stalls, because their pressure-ratio across the compressor is lower and hence every single stage has to work much less hard than on a two- or three-spool design (they're more optimized on the correct mass-flow there, hence they have a higher pressure-ratio across each-stage, which in turn makes them more likely to stall).

 

The interesting part would be how much *too much* fuel needs to be injected to shut the engine down (too rich mixture).

The result (engine fire) would be the same, though.

 

 

9 hours ago, LuseKofte said:

I think A German pilot serving in Argentina said something like he would have loved seeing the 262 with Meteor engines

 

No, he wouldn't. The 262 with radial compressor engines would have been a flying brick - just like the Meteor.

Meteor also had a reputation for killing lots of pilots. But that was the story of any jet at the time.

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Posted (edited)

As a big fan of the Me-262, and in general of this enthusiastic community (which is much less toxic than the DCS one, a big praise to everybody), it is hard to say for me - but this thread is letting me feel embarrassment and somewhat of a headache.

 

I don't know why these alternative facts are still getting around. You guys may want to read up what the German sources say on increasing the throttle too fast - it's "Flammabriss". That's "choking out" to a Jet.

 

It will not lead to an explosion. It won't melt. Flammabriss refers to the engines simply choking out. Cut the throttle and the excess fuel gets shoveled out. They then need to get restarted, which is a lengthy process that takes the pilot's attention, but possible in flight while they still revolve. That is all. They don't blow up. It's still very dangerous though, as it means you'll be a sitting duck and it's especially dangerous when gliding in on the long descend to landing.

 

Wherever this narrative of Me262s blowing up comes from, it's not from increasing the throttle too quickly, but for different reasons, usually getting shot at or landing on the engines with damaged fuel containers and spark flight. The rest is allied propaganda of the time.

 

There have been 1423 Me262s built in series and the first prototype flight was 1942. No typo there. 1942. Some things may have happened before the series hit, with prototypes, but I couldn't find a single report of an Me262 blowing up or the engine damaged after increasing the throttle too quickly. Not a single one.

 

Whoever says this is welcome to provide evidence. In original German documentation. It can get run through the translator, and I am willing to help if Google isn't able to properly translate something.

 

Keep it rocking guys, happy Easter & best regards

 

Fenris

 

P.S. Another comment found here was "short flight time". Range is >1000km, flight time recorded with 50-90 minutes. I cannot decide on how these two sentences would fit together.

Edited by SCG_Fenris_Wolf
P.S. added
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25 minutes ago, SCG_Fenris_Wolf said:

It will not lead to an explosion. It won't melt. Flammabriss refers to the engines simply choking out.

Jet engines typically run rather lean. So there is typically some headroom for making a bigger fire before you‘re extinguishing your burn in jet fuel. If you have an engine with such little margin in stability such as those „B“ Jumos, it will be certainly not a great idea to rely on your argument. Besides, each time you take chances by walking the throttle forward too fast (even without the burn being „drowned“), you‘ll overheat the engine. If a factory fresh engine has a TBO of ~12 hours, guess what out of spec treatment can do to your engine in a 1 hour flight.

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Posted (edited)
50 minutes ago, SCG_Fenris_Wolf said:

P.S. Another comment found here was "short flight time". Range is >1000km, flight time recorded with 50-90 minutes. I cannot decide on how these two sentences would fit together.

 

@ Altitude, @ Cruise power.

 

Whizz around at high power at low altitude and you'll burn through your gas rather quickly. Especially on a straight jet/ turbojet.

That's a basic constraint on any jet-powered aircraft, including turboprops.

 

50 minutes ago, SCG_Fenris_Wolf said:

I don't know why these alternative facts are still getting around. You guys may want to read up what the German sources say on increasing the throttle too fast - it's "Flammabriss". That's "choking out" to a Jet.

 

It will not lead to an explosion. It won't melt. Flammabriss refers to the engines simply choking out. Cut the throttle and the excess fuel gets shoveled out. They then need to get restarted, which is a lengthy process that takes the pilot's attention, but possible in flight while they still revolve. That is all. They don't blow up. It's still very dangerous though, as it means you'll be a sitting duck and it's especially dangerous when gliding in on the long descend to landing.

 

Wherever this narrative of Me262s blowing up comes from, it's not from increasing the throttle too quickly, but for different reasons, usually getting shot at or landing on the engines with damaged fuel containers and spark flight. The rest is allied propaganda of the time.

 

A flameout ("Flammabriss") isn't all that simple. You might have excessive gas spraying around on hot engine parts with less than optimal cooling.

Depending on the situation, you might have an EGT-spike and a tailpipe fire.

 

41 minutes ago, ATAG_SKUD said:

ttp://www.zenoswarbirdvideos.com/Images/Me262/262PilotHandbook.pdf

Interesting...Page 11/28... "The airplane holds its speed in tight turns much longer than conventional types"

Every sim that has modeled the 262 previously had the the 262 bleed speed egregiously with any  type of turns.

 

What does the manual specify as "tight turn"?

It probably has a slightly better sustained turn than most prop-fighters at combat speed, but once all the energy is gone (like after going for instantaneous g for too long), you'll be in trouble getting your speed back. That is unless you trade altitude.

 

Bottom line is: Don't get too slow and you'll be fine.

It's just another airplane.

Edited by Bremspropeller
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On 3/15/2019 at 5:22 AM, Gambit21 said:

 

The SR-71 turns better at mach 3 than the Sopwith Camel does!  

 

That’s about how silly this debate of yours is - the actual conversation/context is either meaningless to you, or you fail to perceive it.

Not as silly as you think!

 

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1 hour ago, Bremspropeller said:

What does the manual specify as "tight turn"?

It probably has a slightly better sustained turn than most prop-fighters at combat speed, but once all the energy is gone (like after going for instantaneous g for too long), you'll be in trouble getting your speed back. That is unless you trade altitude.

 

Bottom line is: Don't get too slow and you'll be fine.

It's just another airplane.

Agreed on trading energy for alt if you take a jet and a prop at equal starting energy states and the prop aircraft loses energy faster than the jet every time both aircraft entered into a maximum rate turn then the jet gains an energy advantage on each pass If the jet extends into an energy conserving climb like hi yo-yo before the prop aircraft is able to take advantage of superior acceleration. It seems the prop aircraft is doomed once it is finally is bled down to 1g stall speeds and becomes a strafe target after successive re-engagements.

Regarding sustained turn rate...If the sustained rate of turn is better in the jet then I would think there would be no further energy loss since that would not meet the definition of sustained turn rate. The sustained rate is probably a function of thrust, drag and stall speed. Two out of three likely go to the 262 but it probably depends on forward speed and compressor/prop efficiencies at those speeds and at some point at lower speeds the prop will overtake the 262 in thrust.  I'm sure someone out there  that can give me a lesson on it.

I'd love to see the turn performance chart for the 262.

:salute:

Skud

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Posted (edited)

Zacharias and Bremspropeller, you talk a lot, but it's all just theoretical, stuttering blablabla of how you imagine a jet engine. None of you posted any reports.

 

You might as well post not at all, it would hold the same value. 😂

 

You'll need to post documentation that support your claim. All the German sources mention is Flammabriss. If you claim further actions resembling Michael Bay's movies, you've got to bring something to the table. 

Edited by SCG_Fenris_Wolf
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1 hour ago, SCG_Fenris_Wolf said:

All the German sources mention is Flammabriss.

Nobody contested the fact that slamming the throttle forward would lead to a Flammabriss.

 

Remember that my comment was based on the „forum notion“ that there would be a compressor stall when advancing the throttle too fast, when in fact what happens is extinction (extinction = flammabriss =/= compressor stall). And you supported my argument. I appears I don‘t have to post documentation as I apparently have you supporting my argument. Thank you.

 

But from reading your comment it almost seems like you don’t think that provoking extinction could damage an engine? You honestly want me to post documentation that running an engine out of spec causes damage? (Timer, anyone?)

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Posted (edited)
2 hours ago, SCG_Fenris_Wolf said:

Zacharias and Bremspropeller, you talk a lot, but it's all just theoretical, stuttering blablabla of how you imagine a jet engine. None of you posted any reports.

 

You might as well post not at all, it would hold the same value. 😂

 

You'll need to post documentation that support your claim. All the German sources mention is Flammabriss. If you claim further actions resembling Michael Bay's movies, you've got to bring something to the table. 

 

Are you saying that slamming the throttles forward, causing an excess buildup of heat, did not ever cause catastrophic engine failures?   Sounds to me, you could get a flameout, or you could get a fire, or it could be the case that the materials in the engine just couldn't take it, and you'd get an uncontained and very catastrophic failure.  The notion you have that the worst thing that could happen was simply drowning the engine, doesn't sound correct at all.

Edited by SeaSerpent
minor term correction
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7 hours ago, ATAG_SKUD said:

http://www.zenoswarbirdvideos.com/Images/Me262/262PilotHandbook.pdf

Interesting...Page 11/28... "The airplane holds its speed in tight turns much longer than conventional types"

Every sim that has modeled the 262 previously had the the 262 bleed speed egregiously with any  type of turns.

:salute:

Skud

That is actually good news. Do anyone know range and fuel capacity. I read very different stories about it. 10 minutts in cruise speed. Little over 1000 km range service celing 11000 m

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Posted (edited)
13 minutes ago, LuseKofte said:

That is actually good news. Do anyone know range and fuel capacity. I read very different stories about it. 10 minutts in cruise speed. Little over 1000 km range service celing 11000 m

image.png.608dcc06ea78da19c630c03fb80b2162.png

That´s the fuel capacity.

Not sure about the 600 liter fuselage tank, that one isnt mentioned in some sources but that´s from the August 1944 manual.

Edited by Psyrion
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2 hours ago, SCG_Fenris_Wolf said:

Zacharias and Bremspropeller, you talk a lot, but it's all just theoretical, stuttering blablabla of how you imagine a jet engine. None of you posted any reports.

 

You might as well post not at all, it would hold the same value. 😂

 

You'll need to post documentation that support your claim. All the German sources mention is Flammabriss. If you claim further actions resembling Michael Bay's movies, you've got to bring something to the table. 


What's wrong with being theoretical?

How many hours do you have in the 262?

 

Have you ever even operated a jet engine?

 

A post-flameout EGT-spike and possible tailpipe-fire isn't Michael Bay, but it's an eyecatcher nonetheless. And it's a very real possibility after a botched flameout-procedure.

 

 

FWIW:

The american manual states that advancing the throttles too quickly on takeoff below 7000RPM will lead to a compressor-stall.

There's no mention of flameouts by hot-gunning the throttles - only by going aft of the idle-position.

 

 

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1 minute ago, Bremspropeller said:

What's wrong with being theoretical?

 

Bremspropeller I for one like solid and easy answers. Even if that means me being corrected. 

So please continue to provide facts where mine are useless. I have only interest in people and specific pilot aircrew history. What I pick up on technical issues is normally forgotten very fast. 

I find your info very interesting

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Posted (edited)

The jumo 004 manual from september 1944 says to move the power slowly up to 6000rpm and quickly from there to full power.

image.thumb.png.af59c925133bdc37117b1ed0f5973754.png

 

The (german) Test pilot notes on zenoswarbird quote Firtz Wendel:

image.png.c7d17bacb476e54bbcbbfc37ebfd6289.png

I guess that could come from different people understand "slowly" in different ways.

 

The same Jumo004 manual also says that continous/crusing power is from 7000rpm upwards.

image.png.95510b52b17f86de14fa9a6d73ca5d19.png

Edited by Psyrion
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Well not being the biggest fan of bop. I can see some advantages in it. I always tend to fly underdog planes and bombers. I mean if I go there why not bring the lot. In this pack there are no slow underpowered plane. It is only up to the pilot 

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Posted (edited)

Insufficient airflow for the amount of fuel injected upon startup is what you also commonly call a „hot start“. Todays engines are far easier to handle than the Jumo but if you start ignition too soon, you can still recreate the situation on simpler engines.

 

Wiki on this:

The critical part is injecting the fuel. If the fuel is ignited before there is enough air flowing around the chamber, its temperature will increase dramatically and exceed the design limits of the combustion chamber and turbine blades, thus causing a failure. This condition is known as a hot start.[1]

 

You do that, you go straight back to the hangar, just in case the firefighters didn‘t have to show up.

 

2 hours ago, Psyrion said:

I guess that could come from different people understand "slowly" in different ways.

Slowly means that the rpm increase can easily follow your throttle movement. That is the very fastest you can push forward. That is the crucial aspect. You better do still slower than that.

Edited by ZachariasX
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6 minutes ago, ZachariasX said:

Slowly means that the rpm increase can easily follow your throttle movement. That is the very fastest you can push forward. That is the crucial aspect. You better do still slower than that.

That was in refrence to the two wildly different numbers of either 6000 rpm or 7500 rpm. I said I think those differences might be due to the jumo engineers and the test pilot having a different understanding of what they consider slow lever movements.

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Hmm. I for one are afraid the speed of the 262 are to high to identefy enemy planes in VR, I have a realy big problem with that as it is...

 

And thanks for alle the intresting discusions and tecnical data people here are providing :) . It almost reminds me of the golden days of the UBI forums :)

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On 3/7/2018 at 4:46 AM, =11=Herne said:

I was just watching this vid, which I thought was worth a share. Apparently the engine life was only 25 hours !!
 

 

 

Where’s the engine timers?

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They needed a overhaul at 10 hours changing some heat damaged parts. 25 hours I am not sure any reach that flight time

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5 hours ago, Psyrion said:

That was in refrence to the two wildly different numbers of either 6000 rpm or 7500 rpm. I said I think those differences might be due to the jumo engineers and the test pilot having a different understanding of what they consider slow lever movements.

 

Not to mention the pilot's perception of time when he was all set to land and a P51 appeared on his six!

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1 hour ago, Venturi said:

 

Where’s the engine timers?

15 min at full power according to jumo 004 manual. 

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9 hours ago, Psyrion said:

15 min at full power according to jumo 004 manual. 

 

That's just for life-preservation. If you exced that time, you'll need a hot-section inspection. That is normal with jets - even today.

 

The chances of trashing the engine will increase after that time-frame, but the engine won't fail right away. If will just start eating up itself slowly with a failure somewhere down the road.

Basicly the same story as with a high-powered piston engine - it's a matter of parameters, not a matter of time.

 

With a low TBO to start with, exceeding those 15mins at CRT, you might trash the engine altogether and it's gonna be pulled and salvaged for parts.

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Posted (edited)

Im interested to see if forward frame and that tick glass will have 190s refraction treatment, or law of light refraction will not work on it same like on rest of airplanes i game, pictures they show us didnt still show that part of cockpit. 

Edited by 77.CountZero

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21 hours ago, Psyrion said:

The jumo 004 manual from september 1944 says to move the power slowly up to 6000rpm and quickly from there to full power.

image.thumb.png.af59c925133bdc37117b1ed0f5973754.png

 

The (german) Test pilot notes on zenoswarbird quote Firtz Wendel:

image.png.c7d17bacb476e54bbcbbfc37ebfd6289.png

I guess that could come from different people understand "slowly" in different ways.

 

The same Jumo004 manual also says that continous/crusing power is from 7000rpm upwards.

image.png.95510b52b17f86de14fa9a6d73ca5d19.png

shit this looks so sick, could i ask you for the source file? 

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