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Spiney Norman
26th May 2002, 10:51
As I thought the spin-off discussion on early supersonic flight was getting interesting I thought I'd give it an outlet...If anyone is interested!!!
Although I agree completely with the assertion in Camel Pilots post in the Lindberg v Armstrong thread that the M52 would never result in a supersonic fighter it wasn't ever supposed to as it was purely a research vehicle. However to describe it as 'wierd' as I.M.Esperto has done is unfair. Miles were a company known for investigating unusual and advanced techniques on a very small budget and the M52 was a typical example of this. wether it was a dead-end or would have resulted in the first supersonic aircraft...Well, we'll never know! The X1 was a less ground breaking basic design but it was designed that way to achieve it's purpose..supersonic flight and there is no doubt that this is what it did achieve. I was fascinated to find out it was built to +18/-18g! But that little appeared to have been learned in the use of rocket fuels and organic based lubricants and that a number were destroyed in resultant explosions!

What do you guys think?
Spiney

18-Wheeler
26th May 2002, 11:39
Yes, interesting stuff indeed.
Just digressing even further if I may, I was wondering if anyone knew what the first Soviet supersonic aeroplane was? I haven't been able to find out anything about it specifically.

Perhaps yet another new thread on Barnes Wallis as well? ;)

Spiney Norman
26th May 2002, 12:47
Hi 18-Wheeler.
Soviet supersonic aircraft research is interesting indeed, and as you say, accurate information seems hard to come by. There were certainly rumours, (but no hard evidence), that the USSR first exceeded Mach 1 in May 1947 using a copy of the German DFS 346. This was a swept-wing, dual rocket powered research aircraft designed to achieve Mach 2.65 at 114,000 ft! A huge amount of DFS research fell into the hands of the USSR at the end of the second world war and so did some of their research scientists and the DFS test pilot, Wolfgang Ziese. DFS were a fascinating company in that they developed from a glider manufacturer to a serious research organisation involved with supersonic and stratospheric flight. I'm not aware of any books specifically about their work but if one exists it would certainly be a good read!
Being the type of society that it was in the late 1940's, the USSR can best be described as having a 'distorted' view to reporting facts accurately and it's very unlikely that the DFS 346 did fly supersonically in that country. It would appear that the first supersonic Soviet aircraft was the Lavochkin LA176, which was supersonic in a dive and was designed to be the worlds first truly supersonic fighter but in fact was quickly superceeded by better designs. The first published date I've seen for the LA176 going supersonic is 26th September 1948. I stand to be corrected on this however!

Spiney

CyclicRick
26th May 2002, 20:30
Supersonic flight:

I recently read an article concerning the breaking of the sound barrier in a German aviation magazine. According to the article the sound barrier was actually broken sometime in 1945 by an Me 262 pilot. The story goes that he was off on a test sortie when he was re-called to base asp. He was somewhere over Austria at the time at a pretty high altitude. He turned for home stuffing the nose down at full power when he started to experience pitching, buffeting and slight control reversal ( all things associated with trans sonic flight), when suddelly all everything went fairly quiet. The pilots at the time were forbidden to carry out any high speed flight at the time due to the precious lack of Me 262's at the time, so he kept quiet about it. The only thing that (after landing) let him down was the evident airframe buckling that had occured!
If any one is interested I could dig out the article and translate it for you.
There's a chap in the USA building one at the moment fitted with Lear jet engines as far as I remember, anyone know when it's due to fly?

18-Wheeler
27th May 2002, 00:04
Abso-bluddy-lutely fascinating Spiney, THANKS!

Jhieminga
27th May 2002, 03:53
Indeed several Me262s are being built in Seattle, with the first example undergoing engine test in preparation for a first flight sometime in the very near future. They are powered by the commercial equivalent of the F-5's engine. (Could very well be a Learjet engine, but I'm not that familiar with Learjets)

For more info: Me262 project (http://www.stormbirds.com/project/index.html)

CamelPilot
27th May 2002, 06:28
That is some project!

History repeating itself. :cool:

Prince of Dzun
27th May 2002, 06:39
CamelPilot:

I do not agree that level flight was a requirement (as you implied) to qualify as first through the sound barrier . Also your choice of the word " attempt" when referring to George Welsh's flight is not really a good one.
The level flight scenario is simply a reflection of speed whereas the barrier was something else ie a wall . What did it matter if the first man through was in level flight, nose down, or for that matter vertical. First through was First through and if George Welsh did it in a dive then the credit is his. I'm starting to form the opinion that it is not only the Japanese who distort history but others as well. Nothing personal my friend, just trying to tidy things up a bit.

Prince of Dzun

Spiney Norman
27th May 2002, 12:41
Hi Cyclic Rick.
Very Interesting info re the Me262. I must admit, I've never seen any good info on the subject of supersonic flight, either attempted, or by accident in the Me262! The period you mention is fascinating for me because so much new technology was available to pilots, particularly of the Luftwaffe, and yet official control of their exploits was so low that what you actually did with it was pretty much up to you! We'll never really know if an Me262 went supersonic, or the Miethe Flying disc actually flew but wouldn't you like to think so? I know I would.
Messerschmitt did actually build a prototype variant of the Me262 to test the airframe Mach limitations. This being V12 (Werk-Nr. 130 008, VI+AG). But unfortunately, the maximum speed officially recorded for this aircraft was 624 Mph. I'd guess that the stories about supersonic flight in the Me262 are probably inaccurate due to the many and varied problems associated with the Jumo 004 turbojet which was prone to catastrophic failure due to lack of suitable metallurgical research and manufacturing technique. And secondly due to a known fault where, at high speed, the fairing over the starter engine, known as the Zweibel, would detach, sealing the engine exhaust causing an immeadiate flame out and such violent yaw that the aircraft would break up! But, as with all these things...you never know!

Spiney

Chimbu chuckles
27th May 2002, 17:59
My reading of Yeager's book...and watching everything I have ever stumbled across on TV/DVD/Video on the subject leads me to believe,

1/. The US attempt at the sound barrier was conducted in a climb...so if things turned to poo they could slow down quickly.
2/. Even Bell Technical people were dumbfounded/relieved that the Miles M52 was abandoned...they believed it was good technology.
3/. Some 6 months after Yeagers 'official' first supersonic run a scale M52, radio controlled, exceeded the speed of sound.
4/. Lots of good evidence to suggest Welsh was the first man through...hushed up for political reasons...the second time that man was thoroughly screwed in his career...the other time being when the Army Air Corps downgraded his CMH to a lesser award because he was not 'authorised' to take off from Haliewa during the Pearl harbour Attack...he shot down 5 minimum that day...if the US AAC could be that childish under those circumstances I'm certain they could claim the SoS for themselves. Friends of mine who have been supersonic in F86s (Australian version) say it was effortless in a shallow dive and as smooth as silk...can't of been that much of an effort for Welsh.
5/. Watched an interview with an ex ME262 German test pilot from the Reichelin days who claims that SoS was impossible in M262. Way too much drag was his reason, coupled with unreliability.
6/. The drag from the propeller coupled with the way shock waves form on the thick straight wings of WW2 piston fighters means SoS impossible....a lot of VERY talented pilots killed exploring high speeds in Spits, Mustangs etc.
7/. My own father tried VERY hard in early Vampires, Meteors to see how fast he could make them go in the early 50s...full power straight down from above 30000'....and not even close!!:eek:


Chuck.

I have control
27th May 2002, 18:22
The sound barrier was actually broken by a New Zealander called Richard Pearse in 1946. I know this for a fact because I read it in a book. It was on a website as well. Several reliable witnesses, interviewed in the late 1990s, saw they saw him take off in an ingenious, homebuilt rocket plane, fly a complex aerobatic routine and then multiple sonic booms were heard over a radius of several hundred miles.

All this stuff you have heard about Chuck Yeager being first is simply rubbish. Yet another example of aviation history being re-written by the Americans, denying the credit to a brave and ingenious Kiwi...

CamelPilot
27th May 2002, 19:43
Reading it in a book does NOT make it fact! Books are given to us to help us understand. We can only hope that what they say is truth.

Having said that. Richard Pearse was indeed a great aviator. He also claimed to have flown before the Wright brothers. Who do you believe? There is record of the Wright's. There is not one of Pearse's 'attempt.'

I quoted from a book written by one of the country's finest. Respected by all test pilots from the early 40's when he joined Hawker's to the day he died. Many of these were at his Memorial service in February of this year.

What you have to be sure of is "your" facts, because when it comes down to it there is precious few of them. And when you have "your" facts before you where did they come from - books most likely.

I have to say that I don't buy the theory that Welsh broke the sound barrier because there is nothing to back it up. Try finding reference to it on the internet. That there was a cover up is possible but there are no facts. There is plenty on Welsh but nothing about him breaking the s/b. In his own books he doesn't lay claim to it either. Just his efforts in American football, where he was a coach, and a very good one.

This is still a good thread but I would suggest that the pedantic use of knowledge gets us no-where - if you see what I mean. Just for the sake of correctness, the sound barrier is in fact a virtual wall, where the air is compressed until it will compress no more.

Spiney Norman
27th May 2002, 20:31
Chimbu chuckles.
You're spot on regarding the M52 models. I didn't mention them in my original post because I wanted to make the point that the written evidence appears to be that the project was scrapped due to the usual political ineptitude and interference . It would appear that in the final stage of model tests the M52 achieved M1.38 but, and here's the best bit, the model based programme cost ten times the projected cost of the manned aircraft programme! Some years after the M52 programme had been abandoned, (1955), A government white paper was published which stated 'the cancellation of the M52 seriously delayed the progress of aeronautical research in the U.K.' I don't think there is any doubt about this considering that the M52 was not just a simple vehicle designed to penetrate the sound barrier but a turbojet powered aircraft which would have given valuable evidence on transonic wing and intake design, plus useful info on re-heat development.

Spiney

Jhieminga
29th May 2002, 04:29
Indeed there's no such thing as a sound 'barrier'. It's no wall.

What does exist is the transsonic region where airplanes not designed for the speeds in this region will experience many strange (to the untrained) phenomena such as mach tuck, compressibility issues, control reversal, buffetting, unreliable airspeed indications etc.

Now mind the last one there: unreliable airspeed indications! As the airplane is not designed for these speeds, the ASI won't be calibrated for it either! So any story about people flying WW2 era planes 'through the sound barrier' must be taken with a pinch of salt in my opinion. A pilot may well have experienced buffeting and strange readings that made him think that he exceeded the speed of sound, but he might still have been quite a bit slower than that, he was just getting close to the limiting mach number for that specific aircraft.

LowNSlow
7th Jun 2002, 09:50
I seem to recall that when the Bell engineers examined the M-52, they realised that the M-52's all-flying tail would give them the control they needed for the Mach 1 attempt. Up to this point the X-1 had had a conventional fixed tailplane and elevators.

Puts on flak jacket and retreats to bunker......

I have control
7th Jun 2002, 14:26
Chcuk Yeager told me he was sick of the Brits forever whining to him about how the M.52's design had been stolen by the Yanks. He said that the all-flying tail was the particular thing that marked the X-1 out from the M.52 - he confirmed what LowNSlow says, that it was the crucial part of the Bell's supersonic success. However Yeager was adamant that this was an American not a British innovation. If the all-flying tail was indeed a feature of the M.52's design I would be very interested to learn more about it.

btw Yeager also told me that when he left Europe after WW2 he disliked the English more than he disliked the Germans... he is some character!

tony draper
7th Jun 2002, 19:35
The brits had a all flying tail plane installed and working on a aircraft long before the M52 or the Bell x ,will track the article and photo down and post it.

PS. we have a tv prog here run by a guy called Jerremy Clarkson, he is doing a series on speed at the moment, allbeit a light hearted look.
He was talkin about this very thing in his program last week
He showed a clip of Chuck making that statement and immediatly after showed a clip of the early flying tail plane aircraft.

pps, there are dozens of articles on the web re M52, google lists many, here is a snippet I just found.

The M52 was to be the first supersonic aircraft in the world, but the Government-funded project was cancelled abruptly.
Mr Kite said: “It was assumed by Ben Lockspieser, the Minister of Aircraft Production, that it was too dangerous to risk pilots’ lives trying to get through the sound barrier.”
To add insult to injury MLA was ordered to hand its work and designs over to the American Bell Aircraft Company.
A year later Major Chuck Yeager, of the US Air Force made the world’s first supersonic flight in a Bell-X1

Dan Winterland
8th Jun 2002, 22:29
Back to the Me262 topic, some time ago I read accounts from several 262 pilots (can't remeber the source) attacking bomber formations from the considerable heights they started their attack runs. Some mentioned lots of turbulence as the speed increased, then smooth flying with the ASI off the clock having seen it kick just as the flight became smooth. Sounds like SoS to me, although they may not have known it at the time.

Jhieminga
9th Jun 2002, 05:05
I'm afraid I'll have to doubt that. The airflow over a part of the airframe or wings may have gone supersonic, or may have gotten close to it, which could account for some buffet, but not the whole plane. Had this happened the centre of lift would have shifted back and there wouldn't have been enough elevator authority to keep the nose up!

More likely they experienced some local compressibility effects, producing mild 'turbulence' and when they descended the increasing density made the local airflow go back to subsonic.

I don't think the basic Me262 design would be capable of going supersonic, definitively not with a normal elevator! But if anyone can produce some facts on this I'm always interested!

Vfrpilotpb
19th Jun 2002, 20:22
Did not our dithering politians of the mid/late forties give the Miles jet to the Americans( in return for some favour or something), who at that time were far away from total control at SOS speed, it was the discovery of the fully movable or flying rear wings that allowed the Bell company to go on and break the sound barrier and in typical form claimed it as their success only?
I seem to think that Aeroplane monthly did a run on this not long ago!
My regards
PeterR-B

ORAC
19th Jun 2002, 23:03
Don't worry. We made up for it by giving the nene jet engine to the Russians!! :(

macky42
20th Jun 2002, 18:30
The M52 has fascinated me for some time (I even built a crude FS5 model of it). I think there was a C4 program entirely on that subject a couple of years ago, with much the same footage as the J. Clarkson program.
Even though the evidence is compelling that the M52 incorporated the all-flying tailplane long before Bell 'invented' it, I doubt Chuck or any other US authority is likely to accept it publicly. I suppose it is possible Bell arrived at the same solution independently without benefit of the Miles data? The answer lies in the Bell archives :)
I wonder what the Smithsonian have to say about it?

411A
20th Jun 2002, 21:46
Here we have the typical...the Yanks stole us blind...ideas, when in actual fact, the guys at Muroc had nearly ALL the right answers..period.
If Brit engineering was sooooo good, why did the Brit aeroplanes keep "falling apart"?:eek:

ORAC
20th Jun 2002, 22:05
If you add up the Brit aeroplanes which crashed/fell apart and then the X machines which crashed/fell apart - I think you might find a lot more holes in the high desert than in the UK.

411A
21st Jun 2002, 02:23
...yes, generally due to a larger budget, and guys that were really paid to "press the envelope", Douglas D558-2, for example.

ORAC
21st Jun 2002, 06:14
In which we might be in agreement. The military/companies on both sides of the atlantic were willing to press ahea. The MOD/Government backed out in the UK. It does, however, render your snde remark irrelevant.

Bigmouth
26th Jun 2002, 08:17
Those of you believing that anybody broke the sound barrier prior to old Chuck need to take a couple of physics and aerodynamics classes.

Windy Militant
26th Jun 2002, 12:58
I hate to Pee on the cake chaps but I think you'll find that the Germans were the first to regularly break the sound barrier albeit with an unmanned vehicle. Ask any one who was in the South East of England or Antwerp towards the end of the war. The most unerving thing about the V2 was how the sound of the thing arrived after it had landed so to speak. The Idea of an all moving tail plane had ben theoretically postulated by German Scientists quite early on during the war. Whether it was for research on the V2 or not I can't say, but the Germans had a number of very sophisticated supersonic wind tunnels during the war. In fact the Germans had a great deal of data amassed concerning transonic and supersonic flight most of which was seized by the americans during "Operaton Paperclip" (I think)
I also seem to recall that the all moving tail plane was some what of a lucky accident. I can't remember where but in a book about the X planes I rember a quote from an engineer who said something along the lines that the original tail surfaces were conventionally arranged, however there was a provision to alter the pitch of the horizontal stabilizer using screwjacks. After a number of transonic flights it was found that the pilots were unable to hold the forces by hand so a modification was made to allow the stabilizer to be moved in flight. This was found to work so well that the elevators were locked off and the screw jacks used for control at all times. I'll see if I can find the source to back this up.

macky42
26th Jun 2002, 20:55
Doubt that Miles had the German data to hand when they designed the M52 in 1943...
Neither Bell nor Miles 'invented' the all-flying tail, they were used on some WW1 aircraft. The point is that Miles anticipated the benefit of using it on a transonic aircraft, and specified it from the outset. How Bell arrived at the solution is also not really the point, but they didn't apply it first and credit should be given where due (imho). ;)

Lu Zuckerman
26th Jun 2002, 22:46
I never got close to a V-2 but I did work on the Redstone, which was developed from the V-2. The Redstone and I assume the V-2 as well was steered by carbon vanes (4) which projected into the rocket exhaust. These vanes depending on which were used could place the V-2 / Redstone on the proper target azimuth, the proper roll pattern and then control the ballistic trajectory. You also must understand that not only technology developed by the Germans was appropriated by the Americans (and Russians) they got the top engineering staff from both the missile and aircraft development programs so if the Germans had developed the technology it would most likely be applied by the Americans. So the question still remains who really did develop the controllable tail plane? After all the British got some of the technology as well.

:confused:

I have control
26th Jun 2002, 22:49
So far I have just seen statements: "Miles invented the all-flying tail" or "No they didn't, Bell did".

Can anyone direct me to books or websites that might have some research on this debate?

Lu Zuckerman
27th Jun 2002, 00:50
This article was taken from a website about the X-1 series of test aircraft. It alludes to previous research which dictated the use of a controllable horizontal stabilizer but it does not state who did the research.

"The Langley Memorial Aeronautical Laboratory, Hampton, Va., designed the instrumentation requirements for the craft, which included rate-of-turn recorders, pressure-distribution orifices on the wings and tail and pedal-force transmitters, as well as other data-gathering devices. From research acquired during earlier tests, the committee proposed installing a movable horizontal stabilizer. This element became crucial when Ship No. 1 reached Mach .94 and its elevators lost their effectiveness. So important was the all-movable horizontal stabilizer that virtually every transonic and supersonic aircraft since that time has had one".

:confused:

Spiney Norman
27th Jun 2002, 11:13
Although the point of who invented, (or came upon), the all moving tailplane has always been a contentious subject I have a feeling that this is one of those subjects that their will never be a definative answer to. The German wartime researchers were working on jet and rocket aircraft through many companies and following many paths but nearly all these projects were designed to operate at high subsonic speeds. I guess this is because there really was no practical need to attempt to push on to supersonic speeds because of the opposition they were facing. They were, after all designing warplanes to reverse a very dire situation. However, this is not to say that research may have concluded that an all-moving tailplane would not have existed in records captured by US forces at the end of the war. The most advanced German supersonic project was the DFS346 but this fell into the hands of the Russians. There's no doubt that Miles did fly their all-moving tailplane and that the research was sent to the US by the Attlee government. Evidence seems to indicate that Bell may have stumbled on the same answer following practical problems with the X1 project. My theory, for what it's worth, is that in fact a number of people hit on the solution and...a). The Germans probably hit on the solution at about the same time as Miles but ran out of time to persue it. b) The British had their project ruined by the usual lack of money/idiot political interference. But c) The US had the funds and the drive to push through their project.

Spiney

Prince of Dzun
27th Jun 2002, 11:21
Bigmouth:

It's general knowledge now and freely admitted by all who know that as far as the USA scene is concerned your Chuck was second. George Welsh was first. One does not need lessons in physics and aerodynamics (as you suggest) to hear a sonic boom or observe windows rattling. Sometimes simple things spell out the truth.

Prince of Dzun

I have control
27th Jun 2002, 15:29
Spiney Norman

I agree with your conculsions.

Prince of Dzun

I'm not sure about yours. If rattling windows and loud noise were evidence of supersonic flight then the sound barrier was broke long before 1947...

Prince of Dzun
29th Jun 2002, 05:47
I have control:

You miss the point. The attempt was announced and it arrived on time. It was not a case of rattling windows as a result of something like a botched noise abatement or low level aerobatics. George Wells should have the credit.

Prince of Dzun

overfly
2nd Jul 2002, 23:30
IHC, you asked for references? There's a very interesting history of Miles called 'Wings over Woodley' which has some relevant bits of info IIRC. Also much of the local knowledge still extant can be found in or via the aviation museum just on the edge of the old Woodley airfield. http://www.bigwig.net/museumofberkshireaviation/mba.htm
and http://www.personal.rdg.ac.uk/~snqfree/ for further links.
hope this helps a little bit...

Bigmouth
3rd Jul 2002, 08:05
Prince, If it´s the first time out how do you know what a sonic boom is and what it sounds like?

Prince of Dzun
3rd Jul 2002, 11:13
Bigmouth:

If you happened to be sitting in a bar and a loud explosion type noise suddenly occurred and the windows rattled wouldn't you turn to your companions and say " what's that?" They wouldn't be able to tell you but later when the facts came out they (and you) would realise it was associated with Geroge Welsh's flight and that same noise would then be known as a sonic boom. Easy enough to understand -!! What isn't so easy to understand is why people refuse to accept something that is so obvious. You have my reasons for giving the credit to George Welsh so how about you spelling out your reasons for denying him. Any other deniers please feel free to speak up.

Prince of Dzun

I have control
18th Jul 2002, 14:51
Prince of Dzun

Intrigued by your posts about George Welch potentially breaking the sound barrier before Chuck Yeager I got my hands on the book "Aces Wild" by Al Blackburn, which seems to be the main source of this story.

The book is written in a style which does not inspire confidence in its historical accuracy: for example extensive "conversations" between leading players in the story are quoted extensively in a verbatim fashion, when the author is obviously making them up based upon what he imagines was said. Throughout the book the author demonstrates a clear bias towards the work of North American Aviation (who he once worked for) and this seems to cloud his judgement of historical sources.

Despite the hyperbole on the dustjacket, the book does not actually contain any evidence that Welch flew through the sound barrier before Yeager, other than pure hearsay. Indeed, the people that Blackburn actually bothered to speak to told him that Welch did not do it.

It does seem clear from the book that Welch actually went through the sound barrier several months before he "officially" did, but he did it after Yeager.

I think a lot of people (including Blackburn) would like Yeager to have been second because they don't like Yeager's personality style, but on the evidence of this book I don't believe it happened.

Woff1965
28th Jul 2002, 00:23
Just a few points - the ballistic shape of the V2 rocket was based on the Mauser spitzer rifle bullet.

I recently acquired a copy of Capt. Eric Browns book "Duels in the Sky" in which he discusses the handling characteristics of the Me262, he state that the official Luftwaffe notes were that the pilot shoud avoid dpeeds over 0.83 mach as the nose would drop requiring a 2 handed pull-out.

What makes this doubly interesting is that Capt Brown would probably been selected to pilot the M52.

Also the Rayal Aeronatical Society published a report on the technical feasibility of M52 in the 70's in which they concluded the design, propulsion and structure were all sound and the aircraft would probably have been successful if built.

lunkenheimer
29th Jul 2002, 21:56
Regarding the all-flying tailplane, many many early aircraft had this feature, such as Curtiss floatplanes, and I believe the Antoinette. I think perhaps the question is rather who realized that it was the solution to mach 1 controllability...

BTW, George's last name is Welch...at least if you are referring to the P-40 pilot out of Ewa Field on Dec. 7 '41.