Zyzygie’s Mumbles and Rambles

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Reluctant Poster said:
Dogfighting died with the introduction of the monoplane. Dogfighting died with the introduction of the jet. Dogfighting died with the introduction of air to air guided missiles, yet somehow it is still with us.
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Yes and no - if you look into aerial combat since the Vietnam war, many of the kills scored were done so without the traditional dogfight. When there were limited ROEs most kills were BVR. I think during the Gulf War there was only one or two VR "dogfights," one where an Iraqi pilot flew into the ground trying to evade an F-15. Even at VR, it seemed most encounters were straight forward (to coin a phrase). As I said many times, today, If you're "dogfighting" either some politician has you fighting within some rigid ROE or something went very wrong and you pissed away several million dollars of technology.
 

Try comparing it with the Naval Weapons Forum NavWeaps Forums which I suspect shows significantly more drift. For example, a thread on the Italian navy The Italian Navy in WWII: Roast It seems today to be on aircraft especially in the Far East. A thread on Battle Name for Sinking of the Bismarck also seems to have moved to aircraft. Another thread Best secondary armament for RN WW2 battleships? seems to have drifted so far into politics that the moderator locked it. Of course, this is just my attempt to cause thread drift in this thread.
 
*****

Talk about grasping at straws Bada. But maybe that's an exaggeration. You don't even have any straws to grasp.

The tendency to surge was far greater in a JUMO than a Derwent.



As Adolf Galland said, the figure of 25 hours was optimistic; 12.5 hours was what was achieved in service.

See the attachment. The steep operating lines of the axial compressors (dashed) against the centrifugal (solid) mean that they have much lower flexibility in operation before surge occurs. Assuming you are capable of understanding a graph, the steep operating lines of the axial compressors mean that they have a much smaller operational window before surge occurs.

In support of this is the statement re the Jumo 004:

"...Cavitation takes place so easily in many compressors as a result of small constructional faults or as a result of foreign bodies that they become entirely unserviceable..."
From Pilot Notes on Me 262 by Flug Kapitan Wendel

From The Me 262 Project:


From the Me 262 Pilot's Handbook -


The Me 262 was liable to fall apart if it tried any aerobatics:


Frankly Bada, the Me 262 would not have been allowed anywhere near service in any self-respecting Allied air force. But OK, the Luftwaffe was understandably desperate. See the section on Powerplant on the following link. But this has been confirmed many times elsewhere:

https://0201.nccdn.net/1_2/000/000/0e0/f98/Me262-Documentation.pdf

These items have been brought up many times before. As they say, no further correspondence will be entered into in these matters...

Credit:
The jet Engine Rolls Royce
Gas Turbine Handbook Principles and Practices
Flight International archives
 

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Sorry, but that's cherry picking.

The workmanship on the Me262 declined due to worsening conditions and contrasted greatly from the models built in 1944.

Slave labor, sabotage, assembly disbursement and constant bombing took it's toll on the 262's quality along with many other machines being assembled, like the He162, for instance.

Unlike the Brewster F3A, which had no excuse for it poor quality...oh, but that's an Allied aircraft, so it should be perfect no matter what, I suppose.
 

Well OK...
But there's a lot of cherries to pick from...
 
Understand that Hans Fay was not a combat pilot AND he was ferrying Me262s to the front late-war (read: 1945) including the one he defected in. Yes, his comments could apply to the ones he was ferrying. They were literally assembled in a forest alongside an autobahnn from components partially assembled in similar locations and trucked to the final assembly point (often being attacked by Allied ground attack) and flown to the front for immediate service AND eventually flown into combat from the very location that were final assembled.

By the way, compare Brown's assessment against Fay's and you'll see a glaring contrast.
 

I don't like straws, the noise they make when sipping is very annoying.

So, you only provide general Technics quotes. That's nice, this way i can also prove you my honda engine is much better than any amercian V6/V8 engine because it's better engineerd.
But is it actually better?!?
Can you provide any copies of Jumo testing showing surge that could confirm your saying? Something from Rechlin, Junkers, Rae or Naca? a real document?
And if you can't understand that combat maneuvres have nothing to do with acrobatics, further discussion is pointless.
ALL Combat maneuvres in an airplane start with ailerons, if those are irresponsive, you're just a sitting duck, a flying platform and not a combat airplane.
A fully loaded C5 Galaxy has a better role rate than the meteor, what means it could be a better fighter than the meteor.
Pilots don't ask the 262 or the meteor to perform a show like an extra 300, they ask to be able to execute maneuvres (changing azimuths/angles ) rapidly enough to save their life and follow the target through the whole flying enveloppe...just like the 262 flew above the bombers stream and their escorts...what was the average altitude of the B17 boxes again?
 

Well OK, but that's just how things were. Bad construction standards were a German problem, whether from field assembly or slave labour.

Fay was arguably a good, unbiased source of information on the merits and demerits of the Me 262:

31 March 1945: Messerschmitt Aktiengesellschaft test pilot and technical inspector Hans Fay (1888–1959) defected to the Allies at Frankfurt/Rhein-Main Airfield, Frankfurt, Germany.

He brought with him a brand-new Messerschmitt Me 262 A-1 twin-engine jet fighter.

Fay had been waiting for an opportunity to bring an Me 262 to the Americans, but feared reprisals against his parents. When he learned that the U.S. Army controlled their town, he felt that it was safe to go ahead with his plan.

On 31 March, Fay was ordered to fly one of twenty-two new fighters from the Me 262 assembly factory at Schwäbisch-Hall to a safer location at Neuburg an der Donau, as they were in danger of being captured by advancing Allied forces. His airplane was unpainted other than low visibility Balkenkreuz markings on the wings and fuselage, and standard Luftwaffe markings on the vertical fin. Fay was the fourth to take off, but instead of heading east-southeast toward Neuburg, he flew north-northwest to Frankfurt, arriving there at 1:45 p.m.

http://zenoswarbirdvideos.com/Images/Me262/ME262PILOTDEBRIEF.pdf
 

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Note the date: March 1945.

That Me262 was most likely not assembled in a factory.

And German machines were manufactured with a high degree of quality until late war. Not sure where you're getting your "bad standards" from, unless your also referring to late war.
 

"...Slave labor, sabotage, assembly disbursement and constant bombing took it's toll on the 262's quality along with many other machines being assembled, like the He162, for instance..."

GrauGeist

Well OK, but that's just how things were. Tough, Germany...
 
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Re surge:

Wendel called it "cavitation."

https://watermark.silverchair.com/v...S87JkXUylFqmTG70LHGKtuQXDx5vj3j55YK6bElZ861Zw

"...Some insight relating to the engine operation of the Jumo 004 engines can be obtained from a direct translation of Messersclunitt's test pilot Fritz Wendel's flight notes presented in Boyne (1980). Excerpts pertaining to the engines have been presented in the Appendix. It is interesting to note the concern relating to surge (called "cavitation" by Wendel), during engine acceleration..."


PILOTS NOTES ON ME 262 BY FLUG CAPITAN FRITZ WENDEL:
"In addition to studying the condensed instructions for airframe and engines, a thorough knowledge of these notes, preferably before the first flight in an Me 262, is essential to the pilot.
1. Taxiing
Always accelerate the engines slowly.
The gas temperature must never rise above the permitted value and the engine must not "roar" (bullern). In view of this, only take corners by using the brakes, never by using the engines. Always taxi gently and never make sharp turns, otherwise control of
the aircraft will be lost.
2. Take-off
Switch on the fuel pumps in the main tanks. Hold the aircraft stationary by applying the brakes and then slowly run up the engines, especially slowly up to 7,500 r.p.m. The brakes must be so adjusted that they will hold the aircraft stationary up to 8.500 r.p.m.
After releasing the brakes, push the throttle lever right forward and then check over the engine. The aircraft makes so little demand upon the pilot at the commencement of the take- off run that he is easily able to carry out this check. The check is done by eye and ear, the engines must not "roar" and the instruments must show the same values as they did during running up or during previous take-offs. The gas pressure must be especially watched, and if it is more than five percent lower than previously, do not take-off. In such a case, it is most likely that cavitation has taken place in one of the compressor stages, that is, by running up too quickly, the compressor has been overloaded and the smooth flow breaks up, exactly as it does when a wing stalls. Cavitation takes place so easily in many compressors as a result of small constructional faults or as a result of foreign bodies that they become entirely unserviceable. It the take-off is continued when cavitation has occurred in the compressor, then the quantity of air flowing through is too small, the quantity of fuel injected however is the same or sometimes even larger, as a result of which, the engine is overheated."
 
GrauGeist said:
What's the date of his notes?

He was the first to fly the 262 under jet power (when the airframe was configured as a tail stagger) and it was equipped with the early 004 engine.
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25th May 1945.

See:

http://zenoswarbirdvideos.com/Images/Me262/ME262WendeL.pdf

Look Grau, the bottom line is that both the Me 262 and the Meteor III were pretty hairy at first.

The Me 262 was by far the better interceptor and the Meteor was the better dogfighter and ground attack aircraft.

But we have to pay tribute to those engineers and technicians and airmen who risked everything by sailing into uncharted waters in the developing of the early jets and hitting the sound barrier.

The great Nietzsche says it best:

"...We aeronauts of the spirit! - All those brave birds which fly out into the distance, into the farthest distance - it is certain! Somewhere or other they will be unable to go on and will perch down on a mast or a cliff-face - and they will even be thankful for this miserable accommodation! But who could venture to infer from that, that there was not an immense open space before them, that they have flown as far as one could fly! All our great teachers and predecessors have at last come to a stop... It will be the same with you and me! But what does that matter to you and me! Other birds will fly farther! This insight and faith of ours vies with them in flying up and away; it rises above our heads and above our impotence into the heights and from there surveys the distance and sees before it the flocks of birds, which, far stronger than we, still strive whither we have striven, and where everything is sea, sea, sea! - And whither then would we go? Would we cross the sea? Whither does this mighty longing draw us, this longing that is worth more to us than pleasure? Why just in this direction, thither where all the sums of humanity have hitherto gone down? Will it perhaps be said of us one day that we too, steering westward, hoped to reach an India - but that it was our fate to be wrecked against an infinity? Or, my brothers. Or?..."

 
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