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D.H.S.
02-22-2005, 09:43 PM
The P-47 was the first aircraft to break the sound bearrier? It did it in a dive when the pilot tried to pull up the wings came off. Is this true?

D.H.S.
02-22-2005, 09:43 PM
The P-47 was the first aircraft to break the sound bearrier? It did it in a dive when the pilot tried to pull up the wings came off. Is this true?

BBB_Hyperion
02-22-2005, 09:51 PM
NO

VFA195-MaxPower
02-22-2005, 10:51 PM
I think late spits and p51s would become transonic in a dive and encounter compressability problems.. I heard an anecdote that claimed that a me262 pilot broke the sound barrier, and the resulting pressure sucked some bolts out of his wings. He said that the cockpit started to sound funny, the airspeed indicator was off the dial and that there was a lot of buffetting.

There is a documented case of a ww2 ace turned test pilot who broke the sound barrier in a dive in his sabre jet before Chuck Yeager. Full sonic boom and all... But Chuck Yeager was the first one to do it in level flight, I think.

darkhorizon11
02-22-2005, 10:59 PM
Actually once the airflow around the entire a/c passes into supersonic things get smooth again. Buffett is transonic range because some of the air is still flowing at a subsonic rate causing vibrations that will rip a conventional WWII prop fighter to threads. Case in point, just because he got buffett doesn't mean he broke it.

Not to mention thick 4 and 6 series NACA airfoils (that the P-51, P-47, P-38 had) don't fair to well in the transonic and supersonic ranges. I doubt you could get one through the barrier with the wings and empennage still attached, nevermind in level flight.

LuckyBoy1
02-22-2005, 11:01 PM
Nope, Russian flown P-63 was first to truly break the sound barrier.

heywooood
02-22-2005, 11:03 PM
I can break the sound barrier....if I eat too much broccoli.

"ch-ch-choppin' broccoliiiiyah!" - Dana Carvey

JR_Greenhorn
02-22-2005, 11:23 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by VFA195-MaxPower:
There is a documented case of a ww2 ace turned test pilot who broke the sound barrier in a dive in his sabre jet before Chuck Yeager. Full sonic boom and all... But Chuck Yeager was the first one to do it in level flight, I think. <HR></BLOCKQUOTE>Wasn't that George Welch, of Pearl Harbor fame?

VFA195-MaxPower
02-22-2005, 11:23 PM
There are a lot of reasons for the aircraft to buffet when it is under a lot of stress. The Spitfire was know to vibrate as it approached stall speed. The fact that modern aircraft transition smoothly does not mean that the me262 would have. The me262 is not shaped like a supersonic fighter, and it would have a lot of its protruding parts intersecting the supersonic shockwaves.

This is a quote from the pilot:

"The airspeed indicator was stuck in the red danger zone, which is over 1100 km/hr.

I noticed that rivets began popping out of the tops of the wings.

The airplane began vibrating and shaking wildly, banging my head against the sides of the cockpit.

After diving about three miles I again regained control and was able to return to base.

On the runway the mechanics were very surprised by the appearance of the airplane, which looked as though it had been shaken by the hand of a giant."

If the IAS of over 1100 km/h was true, he was very close to the absolute speed of sound, especially if he was at altitude. The speed of sound at 4000m is 1166.4 km/h.

Now, I'm not saying that he did break the sound barrier, but your argument claiming that since his aircraft wasn't rock stready over its maximum indicated airspeed that he didn't break the sound barrier is not sufficient to debunk the claim.

wayno7777
02-22-2005, 11:31 PM
There was a report that as he approached the sound barrier, his ASI was reading inaccurately due the airflow eddying wildly. They do claim to have done it, though. Looking for the link. Can't find it. IIRC it's posted in these forums somewhere.



Search is useless. http://forums.ubi.com/images/smilies/35.gif

Syama
02-23-2005, 12:09 AM
I can break the sound barrier, just need a whip.

tjaika1910
02-23-2005, 12:16 AM
Several pilots died because they reached the sound barrier. To break it in one piece, without a sonic aircraft, and tell about it? Did that really happend?

pourshot
02-23-2005, 01:31 AM
I dont think any prop plane can pass the speed of sound becuase the prop will produce way to much drag. This topic has been done before with the same conclusion.

pourshot
02-23-2005, 01:49 AM
As for the me 262 (http://www.aerospaceweb.org/question/history/q0198c.shtml) read this.

SnapdLikeAMutha
02-23-2005, 01:51 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by pourshot:
I dont think any prop plane can pass the speed of sound becuase the prop will produce way to much drag. This topic has been done before with the same conclusion. <HR></BLOCKQUOTE>

supposing you got rid of the prop?

pourshot
02-23-2005, 02:03 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by SnapdLikeAMutha:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by pourshot:
I dont think any prop plane can pass the speed of sound becuase the prop will produce way to much drag. This topic has been done before with the same conclusion. <HR></BLOCKQUOTE>

supposing you got rid of the prop? <HR></BLOCKQUOTE>

Umm what would you use for thrust?

Abbuzze
02-23-2005, 03:08 AM
It´s doubtfull that a 262 could break the soundbarrier, so it´s even more doubtfull that a P47 can do this and survive it.
If you don´t survive it- it don´t count, cause if a submarine sink into the deepsea after a crash, it´s also no new world record...

Edit: And reaching subsonicspeed close to the soundbarrier will break every WWII prop-plane.

WOLFMondo
02-23-2005, 04:04 AM
A Spitfire IX was recorded as reaching 606mph in a dive but the prop and gear broke off, which is probably the fastest recorded dive of a prop plane. I remember reading somewhere about a guy who tried to get the P47 to the sound barrier and was using special propeller but I think the mach number on the wing prevents it from actually going fast enough. Im sure theres someone here who can explain critical mach numbers on wings etc.

hotspace
02-23-2005, 06:31 AM
Close, that was a Spit XI, m8.

Here's a quote from: A Spitfire Story by Alfred Price. I'm not gonna write all of it as it goes on few a few pages, but here's some rough detail:

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>In 1952 a Spit 19 belonging to No 81 Squadron based in Hong Kong achieved what was almost certainly the highest speed and the highest Mach Number ever achieved by a propeller-driven aircraft.

On 5th February Flight Lieutenant Ted Powles took off in PS852 for a Met Flight climb to 50, 000 feet. <HR></BLOCKQUOTE>

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Carefully he nudged the aircraft higher until eventually his altimeter read 50,000ft - a true altitude of 51,550ft at an airspeed indicatored of 108 knots (275 mph true). <HR></BLOCKQUOTE>

Cut a long story short his plane stalled and went into a dive.....

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>After the flight Powles tried to establish exactly what had happed. He had noted the times when he commenced the dive, when he passed 44,000ft just before the vibration started, and again after pull out. Thus he knew that he had taken 9 seconds to descend from 44,000ft until he levelled out at 3,300ft on the altimeter (which due to lag in the instrument probably meant a true altitude below 2,000ft). The descent through 42,000ft and the subsequent pull out had taken 47 seconds, which meant that during the dive the Spitfire must have exceeded 1,000ft per second, or over 680mph. The aircraft was not fitted with a Mach meter, but Powles had recorded the outside temperatures at 5,000ft intervals during his climb so it was a simple matter to work out the speed of sound for each altitude. After colating the available information and applying corrections for compressibility and other factors it seems likly that the Spitfire reached at least Mach 0.94 at 15,000ft during the dive, equivalent to 690mph. <HR></BLOCKQUOTE>

.......now I'm off for a Pint after writing all that http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Hot Space

Jasko76
02-23-2005, 08:20 AM
And here we go again!

Nope, it was the guy that flew the plane in my sig http://forums.ubi.com/images/smilies/10.gif

WOLFMondo
02-23-2005, 08:31 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by HotSpace:
Close, that was a Spit XI, m8.
<HR></BLOCKQUOTE>

Im talking about the IX that did the 606mph during war time testing.

I read about that one as well which is a ridiculously high speed dive!

TAGERT.
02-23-2005, 09:52 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by darkhorizon11:
Actually once the airflow around the entire a/c passes into supersonic things get smooth again. Buffett is transonic range because some of the air is still flowing at a subsonic rate causing vibrations that will rip a conventional WWII prop fighter to threads. Case in point, just because he got buffett doesn't mean he broke it. <HR></BLOCKQUOTE>Exactally! And that is the ONE thing that Me262 pilot based his whole *story* around.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by darkhorizon11:
Not to mention thick 4 and 6 series NACA airfoils (that the P-51, P-47, P-38 had) don't fair to well in the transonic and supersonic ranges. I doubt you could get one through the barrier with the wings and empennage still attached, nevermind in level flight. <HR></BLOCKQUOTE>That and after the war they did some testing with a P47 and different props in dives where they tired to break the sound barrier.. Never got close.

TAGERT.
02-23-2005, 09:54 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by pourshot:
As for the http://www.aerospaceweb.org/question/history/q0198c.shtml read this. <HR></BLOCKQUOTE>Thats the one, Hans Guido Mutke claims are rubbish

SnapdLikeAMutha
02-23-2005, 10:55 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by pourshot:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by SnapdLikeAMutha:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by pourshot:
I dont think any prop plane can pass the speed of sound becuase the prop will produce way to much drag. This topic has been done before with the same conclusion. <HR></BLOCKQUOTE>

supposing you got rid of the prop? <HR></BLOCKQUOTE>

Umm what would you use for thrust? <HR></BLOCKQUOTE>

An effective substitute would be the wind that is propelling the copious cohorts of tumbleweed that superceded my failed attempt at raising a laugh http://forums.ubi.com/images/smilies/cry.gif

LStarosta
02-23-2005, 02:01 PM
I think someone doesn't know that XI is not equal to 19...

skabbe
02-23-2005, 02:22 PM
the typhoon was the first to brake the barrier in 1941, though it was the thick wings that made the air compress and make the airflow faster then sound. how ever no matter engine or propeller on a plane is not the factor of bring it over supersonic, gravity maybe...

telsono
02-23-2005, 02:35 PM
The XF-84H was an attempt to break the sound barrier with a propellor driven aircraft. It was a failure. The noise produced by the propellors would make the ears of ground crew bleed. You can find information at:
http://www.aero-web.org/specs/republic/xf-84h.htm

Yes, the F-84 was basically a jet aircraft, but this was an unigue test to attempt to get a prop aircraft to break the sound barrier. Only two prototypes were built, one was displayed in front of the passenger terminal ofthe airport in Bakersfield, CA for many years. Several years ago it wasd returned to Edwards Air Force Base to be included in their air museum. I remember seeing it there myself.

darkhorizon11
02-23-2005, 02:57 PM
All national pride aside there are two non-technical reasons why I think Mr. Mutke didn't break the sound barrier.

1. The construction of the Me-262 was weak and in some cases wood. Many metal fighters were shredded due to vibrations in the transonic range.

2. Mr. Mutke didn't open up his mouth about this till years and years after it supposedly happened. Perhaps his memory has left him, this is no disrespect, just that in many cases the human mind subliminally makes its own conclusions about certain things and comes to its own conclusions. I'm not calling Mr. Mutke a liar as he wouldn't even know in his concious self. Its just something the mind does, you want to believe something so over a period of 60 years (unless the event was perfectly documented at the time) the memory slowly becomes what you want it too. Don't believe me??? Ask a cop how many varying eye-witness stories he gets about a crime or a car accident if he waits even just 3 or 4 hours after the incident occured.

Like I said its got nothing to do with pride or not wanting to admit something or give credit where its due. Its just coming to the wrong assumptions, like saying 1+1=3.

Chuck_Older
02-23-2005, 03:06 PM
http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

In order to be considered a 'first', the attempt has to be made under very controlled conditions.

I think some folks are forgetting this is about "First to break the sound barrier in level flight", here.

Yeager's attempt was such an attempt, and he succeeded in this regard first.

There is much desire to 'de-bunk' all sorts of things. A lot of people seem to feel that almost everything officially recorded is off-base and they need to 'prove' that the official accounts are wrong, or biased, or whatever. Yeager did it...first to be proven, and that's that http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

pourshot
02-23-2005, 03:23 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by telsono:
The XF-84H was an attempt to break the sound barrier with a propellor driven aircraft. It was a failure. The noise produced by the propellors would make the ears of ground crew bleed. You can find information at:
http://www.aero-web.org/specs/republic/xf-84h.htm


Yes, the F-84 was basically a jet aircraft, but this was an unigue test to attempt to get a prop aircraft to break the sound barrier. Only two prototypes were built, one was displayed in front of the passenger terminal ofthe airport in Bakersfield, CA for many years. Several years ago it wasd returned to Edwards Air Force Base to be included in their air museum. I remember seeing it there myself. <HR></BLOCKQUOTE>

I just did some reading about this plane. Apparently it was the loudest plane in history, it was so loud you could hear it 35km away. Standing to close it would cause one to loose control of his bowel and even sent one poor bloke into a epileptic fit. http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

Sterf21
02-23-2005, 03:29 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BBB_Hyperion:
NO <HR></BLOCKQUOTE>
that is nonsense dude, it has nothing to do with the TS. Get back to reality and burn the Sun Tzu books.

Chuck_Older
02-23-2005, 03:38 PM
Why? He knew a heck of a lot about his business, didn't he?

Von_Zero
02-23-2005, 04:09 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Sterf21:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BBB_Hyperion:
NO <HR></BLOCKQUOTE>
that is nonsense dude, it has nothing to do with the TS. Get back to reality and burn the Sun Tzu books. <HR></BLOCKQUOTE>
loool
Sterf21, the part with <BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>High Ground is not only more agreeable and salubrious, but more convenient from a military point of view; low ground is not only damp and unhealthy, but also disadvantageous for fighting.

Sun Tzu : The Art of War <HR></BLOCKQUOTE> is Hyperion's sig http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

RedNeckerson
02-23-2005, 04:10 PM
It's quite true.

P-47 pilots in Europe did it on several occassions.

They would cclimb to 30,000ft., point the nose of the Thunderbolt straight down, and the Thunderbolt would remain completely controllable as it broke the sound barrier.

The only way to slow the P-47 down was to fire those eight fifties at German "Tiger" tanks down on the roads. The fifty cal. rounds would bounce off the pavement and up into the belly of the Tiger, effectively destroying it.

MoeLarryCheese
02-23-2005, 07:27 PM
A couple of points.

No propeller plane ever exceeded the speed of sound.
None, never. That simple.
High speed tests in a modified P-47 by Curtiss
after WWII found it to be impossible to exceed
mach1 under any conditions, and the prop was the reason.
The prop blades reach mach1 before the winds
because, as a result of their rotation, they
"travel a greater distance" in terms of air
passing over the prop blades leading edge.
When the baldes reach mach1 all hell breaks loose.
You get asymetrical shock waves and the drag
on those blades exceeds the thrust that could
be provided.

So as you near mach1, the prop acts as a speed brake
as it beats your airframe to shreade with shock waves.


As to the Me-262 exceeding mach1... Another fantasy story
that had bought an old German vetran a few coffies.

There are many reasons why a 262 can not and never will
exceed mach1. just ask the guys that built the replicas.
They are over powered by two GE J-85s and can drive
the airframe to destruction.

I will list a few reasons no 262 broke mach1.

#1, the wing is too thick.
#2, the engine inlets are too big.
#3, the engine fairings and fillets are all wrong
for near mach or mach1 flight.
#4, the fuselage reaches maximum width at the wing root.
That's ok for 500mph speeds, but all wrong for
anything near mach1. Think "area rule" for this one.
#5, the structure is way too weak. I am not dissing the 262
but if you look at planes designed to exceed mach1
the structures are many times more strong
and steel alloys and titaimium are used in quantity.

The first manned plane to exceed the speed of sound
was likely the XP-86 piloted by George Welsh, in a steep dive
a few days before Chuck Yeager did it in level flight.
By the way, the P-86/F-86 was a very strong plane.
It was designed from the outset with mach1 in mind.

By the way guys, some pilots did indeed report
what looked like some fighters breaking the speed of sound
during WWII, it was found the pitot and air speed indicator system
could not deal with high speeds above 550mph.
Erronius readings.

Martin Caidin pushed the BS about the P-47 breaking
the sound barrier in his history/novels such as "THUNDERBOLT"
It is best not to accept anything Martin Caidin wrote as fact.

MLC

javierib
02-23-2005, 07:32 PM
LOL!!! http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif @ Red comments

Aztek_Eagle
02-23-2005, 07:57 PM
one other point here to mention is the one of where u achive certain speed in an airplanen, ur nose will just drop, and recovery hardly posible... the only plane witch has this modelled sadly is the b1 roket..... many spitfire pilots coment, on how at high speeds thier plane would just become uncontrolable....... so in the game, spits dive wiht anything, fw190s, anything......... witch takes alot of relims of the game aswell....

Aztek_Eagle
02-23-2005, 08:09 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by darkhorizon11:
All national pride aside there are two non-technical reasons why I think Mr. Mutke didn't break the sound barrier.

1. The construction of the Me-262 was weak and in some cases wood. Many metal fighters were shredded due to vibrations in the transonic range.

2. Mr. Mutke didn't open up his mouth about this till years and years after it supposedly happened. Perhaps his memory has left him, this is no disrespect, just that in many cases the human mind subliminally makes its own conclusions about certain things and comes to its own conclusions. I'm not calling Mr. Mutke a liar as he wouldn't even know in his concious self. Its just something the mind does, you want to believe something so over a period of 60 years (unless the event was perfectly documented at the time) the memory slowly becomes what you want it too. Don't believe me??? Ask a cop how many varying eye-witness stories he gets about a crime or a car accident if he waits even just 3 or 4 hours after the incident occured.

Like I said its got nothing to do with pride or not wanting to admit something or give credit where its due. Its just coming to the wrong assumptions, like saying 1+1=3. <HR></BLOCKQUOTE>


even a human body can get close to brake the sound barrier, why not a piece of wood or crappy metal?...

i remmember this..... some cientist in a airballoon got to who knows how many km of height, then he bail of the ballon in a free fall.... i cant recall what they were doing wiht the ballon so high, but i do remmember the guys saying the speed of the dive, and that it was close to it.... at high altitudes the air is not as tick, so the negative effect on objetcs falling is less than at lower altitudes witch can help an aircraft top speeds

MoeLarryCheese
02-23-2005, 08:27 PM
Good point....
But the baloon jump you refer to was well over 100,000' up.
The subject reached an estimated 700mph.
But he slowed in a big way as he decended.
If you saw what was left of the Columbia astronauts
you would understand that the human body can not
deal with the pressures of high speeds well at all.

At altitudes WWII era aircraft could reach
there was no way any plane of that era could
reach mach1.

However... the A-4, better known as the V-2
was recorded at over mach4, but it was an un manned missle.
I am surprised that no attempt was made to put
a set of stubby wings on an A-4 and put a pilot in one.

The first air breathing aircraft capable of surviving mach1
was most likely the XP-86/F-86 sabre. But only in a steep dive.

The post about nose pitch down makes an excellent
point. Even the Bell X-1 that Yeager flew had
trouble with un controllable pitch down.
They solved the problem by using the flying tail trim system for control.

MLC

BigKahuna_GS
02-24-2005, 11:22 AM
S!

First dive that broke the sound barrier.

http://home.att.net/~historyzone/Welch2.html

As the XP-86 was being completed, George Welch had already been designated to make the first series of test flights. Welch spent a considerable amount of his time in the engineering offices located at North American Aviation€s Inglewood facility. Here he would grill the design team about the new fighter€s expected stability and handling. Welch also quizzed the team about the prototype€s potential maximum speed. Being informed that the new fighter, now called the Sabre, should be able to handle 650 knots, Welch formulated a plan in his mind that had it been known, would have caused his employer many a sleepless night.

After a series of extensive ground tests, resplendent in its polished aluminum skin, the XP-86 was disassembled and trucked to Muroc Field (later renamed Edwards Air Force Base). On September 18, 1947, Stuart Symington took the oath of office as the first Secretary of the new, independent United States Air Force. Before the XP-86 was ready for its first taxi tests, Symington made a point of notifying North American that he expected them not to steal any thunder from the new Air Force€s pet research project, the rocket powered Bell XS-1. Symington€s orders were explicit. Having been briefed that the XP-86 was capable of exceeding Mach 1 in a dive, the Secretary fully expected that North American Aviation would wait until the XS-1 had made its mark in history before they claimed their portion of the supersonic sweepstakes. Besides, Larry Bell had already complained to the President about North American plotting to upstage his rocket plane.

Unfortunately, the politics behind the scenes were totally lost on Welch. Not only did he not care one whit about Symington or his edict; Welch was a civilian and not employed by the Government. Moreover, George had long since demonstrated a tendency toward independence. Knowing the potential of the Sabre, there was no way that Welch could pass up an opportunity to explore its limits, and perhaps, gain some personal retaliation for the P-39 €œIron Dog€, by sticking it to the guys at Bell.

http://home.att.net/~historyzone/P51h.JPG
One of the first aircraft that Welch tested was the P-51 Mustang. The aircraft above is a brand new, factory fresh P-51H. This was the fastest of the Mustang line, being capable of 487 mph at 25,000 feet.

With the XP-86 reassembled at Muroc, Welch went to work on a series of taxi tests designed to fully explore ground handling right up to takeoff speed. These tests were done on the morning of September 29. Getting an early start, the taxi runs were completed by 10 AM. Everyone was satisfied with the results. Yet, a minor fuel leak promised to keep the mechanics busy for the rest of the day.

That evening, Welch headed for his room at Pancho€s Fly Inn (later renamed Happy Bottom Riding Club) where he normally stayed when at Muroc. A favorite hangout for both the North American and Bell gangs, as well as most of the test pilots on the base, Pancho€s was the place to learn what everyone else was up to. The owner of the Fly Inn, Pancho Barnes, was a rough and tumble aviatrix who had specialized in air racing and Hollywood stunt flying; she had cultivated friendships across a broad spectrum of personalities. These included Jimmy Doolittle and Mae West, to name but two. Built like a linebacker, Pancho was a larger than life personality who had the delicate charm and manners of a drunken cavalry trooper. Naturally, everyone loved Pancho, who all realized as a soft touch for pilots, especially Yeager, who she adored.

Welch went for dinner and a beer, and as was his habit, he spoke with Millie Palmer, a local girl who made Pancho€s her home away from home. Millie was expert at picking up tidbits of information about the various projects at Muroc. Millie mentioned that the Bell folks didn€t expect to be flying before the end of the week. Welch confided his plan to make a supersonic dive during the Sabre€s first flight on Wednesday, October 1. George explained to Millie what she should look for. €œA sharp boom, like a clap of thunder. If you hear that, be sure to write down the time, what it sounded like, the reaction from others, stuff like that.€



http://home.att.net/~historyzone/xf86-2.JPG
If ever any aircaft looked right, the XP-86 was certainly one of them. With perfectly clean lines, the Sabre could not help but be a winner. This is how the XP-86 appeared after being reassembled at Muroc. Within a few days, it would punch through the sound barrier.


Easing back on the stick, Welch began a steady rate climb at just under 350 mph. Zooming up at over 4,800 feet per minute; it took but a few minutes to reach 35,000 feet. As he leveled off, airspeed quickly increased to 370 mph. After a double-check of his instruments, Welch rolled into a 40 degree dive, pointing the nose west, directly at Pancho€s Fly Inn, several miles away.

The airspeed indicator wound up to about 405 mph, and seemed to get stuck there. Yet, there was no doubt that the XP-86 was still accelerating. Everything felt normal, until passing below 30,000 feet where a tendency to roll needed some minor correction. George pushed the nose over a bit more. Then, suddenly, the airspeed indicator jumped beyond 470 mph and continued to go up. Passing 25,000 feet, Welch eased back on the stick and pulled back the throttle. Once again, there was a bit of wing roll and the airspeed indicator jumped back from 520 to 450 mph (520 mph indicated translates to 720 mph true at this altitude, uncorrected).

Contacting Chilton, Welch joined up with the P-82 as it was time to head back to Muroc. Due to ongoing rigging, the speed brakes had been disabled and were not available. This would complicate the landing approach because jet fighters took quite a while to scrub off airspeed, not having a propeller functioning as a giant, circular air brake. Descending towards the lakebed, Chilton slipped underneath the Sabre as Welch slowed and lowered the landing gear. Once again, the main gear locked down. The nose gear, however, refused to extend beyond the halfway position. Welch cycled the gear up and down several times to no avail. He tried the emergency pump. That too failed to push the nose strut into position. Radio discussions with the North American engineers on the ground produced no solution. Welch even tried pulling several Gs of loading. Nothing worked. With fuel rapidly becoming an issue, Welch elected to make a long, straight-in approach. Touching down at 140 mph, Welch trimmed the nose full up, intending to hold it up as long as possible. Racing alongside the Sabre were crash trucks and a pickup with a motion picture camera. As the Sabre€s speed dipped below 90 mph, Welch began easing the nose down. Just then, the nose gear snapped down and locked in place. The wheel touched, and the XP-86 rolled out normally. George€s luck had held again.

Prior to heading back to North American to brief the engineers, George telephoned Millie Palmer. Excitedly, Millie related that a terribly loud ba-boom had nearly blown her out of bed. The time was noted and it corresponded to George€s dive. €œPancho€, Millie related, €œis really pissed. You know how she feels about Yeager.€ Apparently, Pancho claimed the boom was a result of mining operations going on 30 miles away to the north. Of course, no one had previously heard any mining explosions, nor could that account for rattling windows only on the east facing side of the Fly Inn. Welch chuckled and swore Millie to secrecy.

After briefing the engineering team at North American, Welch tracked down Ed Horkey. There were some €œfunny€ instrument readings during the dive, and George was looking for some answers.

Test pilot Blackie Blackburn describes the conversation:

€œI started at about 290 knots€, Welch explained. €œIn no time I€m at 350. I€m still going down, and I€m still accelerating, but the airspeed indicator seems stuck like there€s some kind of obstruction in the pitot tube, I push over a little steeper and by this time I€m going through 30,000 feet. All of a sudden, the airspeed needle flips to 440 knots. The aircraft feels fine, no funny noises, no vibration. Wanted to roll to the left, but no big deal. Still, I leveled out at 25,000 and came back on the power. The airspeed needle flicked back to 390. Whadya think?€

€œWhat did the flight recorder look like?€

€œIt wasn€t on the flight card, I was just feeling it out, so I wasn€t running the camera. Anyway, there wasn€t anything wrong with the airspeed system. They checked it out after I landed.€

Horkey guessed that Welch had run into a previously unknown Mach effect. Indeed he had. What Welch had observed was a phenomenon that would later be called, €œMach jump€. Today, €œMach jump€ is generally considered solid evidence of speeds in excess of Mach 1. Of course, on October 1, 1947, no had ever seen it before.

Welch made the second and third flights with the landing gear mechanically locked in the down position. The revised and more powerful hydraulic cylinder for the nose gear had not yet arrived. So, the gear was bolted down and the gear lever was safety wired in the down position. However, there was another reason for bolting down the landing gear. Welch€s ba-boom had also hammered Muroc. Without saying so, the Bell and NACA people were generally unhappy about the rumors comsuming much of the chit-chat on the base. The XS-1 had still failed to push beyond Mach .98. The chatter around the base was that the XP-86 was responsible for the boom that had rattled windows and scared the hell out of everyone. People had raced outside looking for the telltale plume of black smoke that proclaimed the end of an aircraft, and maybe its pilot. But, there was no smoke. There was no crash. The only excitement centered on the crash trucks racing out to meet the swept-wing Sabre as it returned. All in all, it looked as if Welch had pulled the feet out from under XS-1 program. Even though there was no official statement from North American, despite unconvincing denials by Sabre team, the word was out at Muroc. Welch and the XP-86 had gone supersonic.

As soon as Welch landed after his second low speed flight in the €œfixed gear€ XP-86, he was informed that his wife Jan had gone into labor with their first child. Welch flew the company plane up to Los Angeles, but arrived after his son had been born. That evening, Jan phoned her family to announce the birth of Gilles, and of course, tell them about George breaking the sound barrier. Years later, Jan€s brother Jimmy would recall that he could not determine if Jan was more excited about her new baby, or her husband€s supersonic adventure.

The XP-86 was being prepared for its fourth flight. Again, despite replacing the nose gear hydraulic cylinder, the schedule called for this flight to be made with the landing still bolted down. Welch objected. He argued that there was no solid reasoning for this, and flying with the gear bolted down was downright dangerous. He was right. Without the ability to raise the landing gear, an engine failure could be fatal. Welch argued that the Sabre €œglides like a rock€ with the wheels down. Finally it was agreed that the gear would be unbolted and functional, but the flight test parameters would remain unchanged.

On the morning of October 14, Chilton and Welch discussed how they could disguise another supersonic dive. They decided to maintain a constant chatter on the radio, transmitting test results for tests completed early in the flight. That might work, but there was no way to disguise the sonic boom. It was generally understood that later in the morning, Yeager and the XS-1 would be trying for Mach 1. But, there was still time for one dive before the official title was handed to Yeager.

http://home.att.net/~historyzone/XP-86takeoff.JPG
George Welch roars off of the lakebed runway to begin his October 14th flight. After completing his test card, Welch would climb to 37,000 feet and for the second time in two weeks, dive the Sabre through the sound barrier. This time, he beat Chuck Yeager by just 15 minutes.

Climbing out to 10,000 feet, Welch performed all of the low speed maneuvers and tests called for on the flight test card. Yet, he reported only half the results. Retracting the landing gear, he waited until Chilton gave him a thumbs-up that all looked normal. Advancing the throttle to full power, he eased the Sabre into a climb and soared up to 37,000 feet. As he climbed, George read out the second half of the low speed test results. Leveling off, he checked his instruments one final time. As he did on his first dive, Welch rolled the Sabre into a 40 degree dive and pointed the nose directly at Pancho€s. As the jet accelerated, he read out the last of the test results. Just like the first dive, a little wing roll followed by the airspeed indicator needle jumping announced that he had exceeded the speed of sound. Except that this time, he was going even faster, having started his dive 2,000 feet higher. Unlike the dive 13 days earlier, Welch did not pull off power when he passed 25,000 feet. Instead, he executed a full power, 4g pullout. Welch did not realize it at the time, but this maneuver was to greatly increase the force of his sonic boom as it slammed into the earth.

http://home.att.net/~historyzone/xf86-6.JPG
Flying over Rogers Dry Lake on November 13, 1947, the XP-86 with George Welch at the controls would be officially measured at Mach 1.04 by NACA's Radar Theodolite. The tremendous speed of the Sabre had the potential to cause the Air Force great embarrassment.


Easing off power, Welch scanned the sky looking for Chilton€s P-82. He spotted what he at first thought was Chilton. Then he realized that the plane had more than two engines. It was a B-29, a mothership, lumbering to altitude with the XS-1 in its belly. Slightly behind, on either side were the P-80s of chase pilots Hoover and Frost. It dawned on him that his shock wave might have hit the big bomber. If it had, there was no doubt that everyone aboard would have gotten the message, loud and clear. Finding Chilton, Welch headed back to the base. The landing gear came down as advertised and George greased it in like the pro he was. A few minutes later, after shutting down and climbing out, Welch heard a distant ba-boom. A check of his watch indicated 10:30 AM. Attaining a speed of Mach 1.06, Yeager had finally done it.

That night there would be no celebrating at Pancho€s. The Air Force had clamped a secrecy lid on Yeager€s flight. The party was held at several of the pilot€s houses. A drunken Yeager managed to crash his motorcycle in a knucklehead display of derring-do. Of course, Pancho€s was open for business, and the North American gang had gathered for a few drinks. Pancho was walking on air, her darling boy having blasted the Fly Inn with a boom that broke some large windows on the east side of the building. Major General Joseph Swing (an old friend from the war) was on hand and asked Welch about the two separate booms. The first was extremely loud, the second, 15 minutes later, was far more subdued. Welch suggested that it came from a V-2 rocket out of White Sands. General Swing knew otherwise. Swing had earned a tremendous reputation for his leading an airborne operation that freed over 2,000 American POWs from a Japanese camp on Luzon. Swing€s reputation and his close friendship with General Eisenhower would come into play later.

http://home.att.net/~historyzone/XP-86Welch.JPG
Very few photographs were taken of the XP-86 using color film. This photo, like the previous one, was probably taken on November 13, 1947. Welch can be identified by his unique, orange flying helmet.

Between October 14 and November 4, Welch had taken the Sabre up 19 times, with eight of those being labeled as €œhigh Mach dives€. The constant hammering of sonic booms finally convinced the Air Force and NACA to employ the same measuring equipment used for the XS-1, to determine the actual speed of the Sabre. On November 13, Welch was €œofficially€ clocked at Mach 1.02 and later that same day, Mach 1.04 was attained. On both flights, the airspeed needle had jumped just as before. Between October 1 and February 28, Welch made at least 68 flights, of which, 23 were supersonic. During the same time period, the XS-1 made seven flights, with but only three were supersonic. Indeed, the vast majority of booms heard in the desert over those months belonged to Welch and the XP-86. More importantly, I believe, the Sabre was a real combat aircraft. It had guns. It could deliver bombs and rockets. It could takeoff and land under its own power. No wonder Bell was worried.

Despite the tight security surrounding the XS-1 program, the story of Yeager€s flight was leaked to a reporter from Aviation Week magazine. In an issue dated December 22, 1947, an article appeared with the glaring headline: €œBell XS-1 Makes Supersonic Flight€. The magazine was released on December 20th. The cat was certainly out of the bag.

http://home.att.net/~historyzone/George1947.JPG
George Welch posed for this photo shortly after the Air Force announced that he had flown the XP-86 through the sound barrier. For political reasons, the Secretary of the Air Force post dated the event by nearly seven months.

Dutch Kindelburger was the founder of North American Aviation, and was still president of the company. He happened to be visiting the Pentagon just three days before Christmas when he was informed that Stuart Symington wanted to see him, right now! Upon arriving at the Secretary€s office, everyone else was asked to leave and the door was closed. Dutch was handed a copy of Aviation Week, opened to the XS-1 article. Dutch shrugged, this was old news to anyone who had been at Muroc.

Symington went on to explain that General Joe Swing had seen the article and claimed that Welch had beat Yeager, not once, but twice. Kindelburger explained the odd behavior of the airspeed indicator, and informed the Secretary that testing in November had confirmed the airspeed indicator€s behavior and the fact that the XP-86 had broken the sound barrier. Symington was dumbfounded. He was in terrible bind. The President had promised Larry Bell that the XS-1 would be the first to go supersonic. Not only that, but the fact that the XP-86 €œofficially€ broke the barrier just days after the rocket plane created another problem. Why spend so much money on the XS-1, when its technology wasn€t even needed?

A solution was worked out that included North American sitting on the story until the Air Force felt it was safe to issue a press release. This would allow Symington to get the maximum mileage out of the XS-1 and Yeager. Then, when it was politically safe, the world would be informed of the Sabre punching through the mythical barrier. True to his word, Kindelburger kept the story under wraps. In June of 1948, a press release announced that the XP-86, piloted by George Welch had broken the sound barrier on April 26th.

This the same George Welch who shot down 4 japanese aircraft during the Pearl Harbor attack.

http://home.att.net/~historyzone/WelchTaylor.JPG
Standing before a Curtiss P-36 fighter, one of the few that survived, five USAAF pilots who shot down one or more enemy aircraft pose for a photograph. From left to right: 1st Lt. Lewis M. Sanders (1 victory), 2nd Lt. Phillip M. Rasmussen (1 victory), 2nd Lt. Kenneth M. Taylor (2 victories), 2nd Lt. George S. Welch (4 victories) and 2nd Lt. Harry W. Brown (1 victory). Together, these 5 pilots shot down nine Japanese aircraft confirmed, with 4 probables and two damaged. This amounts to nearly 1/3 of all Japanese aircraft lost during the Pearl Harbor attack. Three of the men are wearing sidearms, indicating that they were probably on duty when this photo was taken.

After December 7th, Welch continued to fly combat patrols around Oahu. However, the news of his four confirmed victories had been released to the press and soon he was ordered back to the States. The country was badly in need of a hero, and Welch fit the bill. After several hectic months of giving War Bond speeches across America, Welch finally received orders to return to the Pacific.

George reported to the 36th Fighter Squadron of the 8th Fighter Group in New Guinea. The good news was that this squadron had been seeing combat. The bad news was that is was flying the hopeless Bell P-39 Airacobra. Welch found himself flying mostly ground support missions, this being largely due to the P-39€s poor combat performance and its limited range. Certainly, the 37mm cannon was useful against ground targets, but the Bell was at a serious disadvantage when facing Japanese fighters.

This was largely the fault of it being fitted with an Allison engine that lacked a two speed, two stage supercharger. This meant that performance dropped off quickly above 12,000 ft. At the altitudes necessary to engage the Japanese bombers and fighters, the P-39 was an absolute dog. Welch did not view the lack of performance at altitude as the primary sin of the P-39. What truly turned Welch against the Airacobra was its limited combat radius. With the majority of air to air engagements being fought beyond the reach of the Bell, opportunities to shoot down more Japanese were nearly nonexistant.

Naturally Welch noted that there were squadrons on his base that were flying the P-38G Lightning. Now, here was a fighter! Fast, long ranging and equally important, its twin Allison engines were turbosupercharged. This allowed the P-38 to climb higher and faster than the P-39. It was everything Welch wanted and the performance of the P-38 was reflected in the tally of Japanese aircraft being shot down. George wanted the Lightning, he wanted it badly and cornered his group commander and inquired as to when 36th could expect to get the P-38.

The answer was: €œWhen we run out of P-39s.€ That was all Welch and the pilots of 36th needed to hear. Virtually any problem encountered in flight (real or imaginary) resulted in a bailout from that day forward. The operational loss rate climbed dramatically. Welch found himself in hot water with the Group commander, who pointed out that George had been very successful in the P-39. Hadn€t he shot down two Vals and a Zero on the one-year anniversary of the Pearl Harbor attack? That didn€t deter Welch, who knew he could have splashed a hell of a lot more if he€d been flying the Lightning. Finally, the Brass gave into Welch€s repeated requests and transferred him across the field to 80th Fighter Squadron. At last, George had his P-38, and he made the most of it.


http://home.att.net/~historyzone/p-38h-8fg.JPG
George Welch would get another nine Japanese in this P-38H. All nine went down in just three engagements.

On June 21, 1943, he destroyed two Zeros over Lae. Then, two months later, George downed three Ki-61 Tony fighters near Wewak. Promoted to captain, Welch was moved to 8th Fighter Group Headquarters. His biggest day since Pearl Harbor came on Sept. 2, 1943, when he killed three more Zeros** (these may have been Ki-43 Hayabusa fighters, called the Oscar by the Allies) and a "Dinah" twin-engine fighter.

The startling thing about Welch€s victories is that they all came in multiples. Virtually every time he found himself in air to air combat, he shot down two or more of the enemy. Shortly after his final kills, George became aware that his rather common case of malaria had grown far worse.

Reluctantly, he reported to the base hospital where the doctors were horrified at his condition and promptly shipped him off to a hospital in Sydney, Australia. His recovery was slow, and the Air Corps decided that George had seen enough combat.

After flying 348 combat missions and 16 confirmed kills, Welch was headed home. One can only wonder what George's final score may have been had malaria not knocked him out of the war. This writer is convinced that Welch would have challenged Bong and McGuire for the ace's crown had he remained in the theater. As it was, malaria sent him home just as things began to heat up in the SWPA.



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ASM 1
02-24-2005, 12:10 PM
Everybody here has been talking about the 262 and the sound barrier... what about the 163 ? now I know it didnt either, but surely it would have got closer than the ME 262, given its higher top speed....

Or would it just have been far too unstable.....?

Zyzbot
02-24-2005, 01:43 PM
Me-163 could not do it. Read the book Rocket Fighter by Mano Zeigler.He describes how the Me-163 goes out of contol at high speeds. This foiled at least one interception of P-38's by Me-163 fighters.


Rudy Optiz...chief test pilot for the Me-163 describes the effect on this web site:

"On the Me 163, the combination of the aft shift in aerodynamic center and shock stall led to a dangerous condition known as €œMach tuck.€ If the Mach number exceeded approximately 0.85, the airplane would begin to nose down on its own. The pilot would naturally react by pulling on the stick and deflecting the elevons upward. This would cause a shock wave to form on the underside of the wing at the elevon hinge line. The elevons would shock stall and be unable to bring the nose up, causing the airplane to pitch over into an ever-steepening dive. The only hope for recovery was to wait until the airplane had dived to a lower altitude where the speed of sound is higher, thus reducing Mach number, and the elevons would regain effectiveness."

http://www.flightjournal.com/fj/articles/me163/me163_6.asp