liedetectors
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Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 7:08 pm

I saw once on a show on TV that an SR-71 pilot stated they flew the SR-71 to Mach 7. I only thought it went to Mach 3.3. Can anyone verify/heard of this?
If it was said by us, then it must be true.
 
David L
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 7:46 pm

You're not thinking of the X-15, by any chance?
 
MadameConcorde
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 7:47 pm

You must be mixing up with the X-43A that flew at Mach7 without pilot (unmanned aircraft).
I am not sure about "Aurora" if it ever existed and/or if it ever flew at Mach7.
There was a better way to fly it was called Concorde
 
nomadd22
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 8:35 pm

Officially the X-15 got to mach 6.72.
Anon
 
rwessel
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 9:06 pm

Sure it did. Right after launching off a Nimtz doing 45kts...

But seriously, no. The thermal issues alone would make it impossible.
 
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Dreadnought
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 9:08 pm



Quoting MadameConcorde (Reply 2):
I am not sure about "Aurora" if it ever existed and/or if it ever flew at Mach7.

Aurora did indeed exist and still does. It was the project name of the B-2 bomber in the early 80s, according to this book:

Rich, Ben, Leo Janos. Skunk Works. Little, Brown & Company, 1994. ISBN 0-316-74300-3
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spudh
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 9:25 pm



Quoting Nomadd22 (Reply 3):
Officially the X-15 got to mach 6.72.



Quoting Rwessel (Reply 4):
Sure it did. Right after launching off a Nimtz doing 45kts...

But seriously, no. The thermal issues alone would make it impossible.

3rd October 1967, X-15-A2 piloted by Captain William J. Knight reached a maximum altitude of 102,100ft, levelled off and accelerated to Mach 6.7 (4,520) a new world record (still is I believe) for 'conventional' flight. The airframe reached 2,700 deg F. The aircraft barely survived but was so badly damaged that it was uneconomical to repair and never flew again. The X-15 used an ablataive coating and this speed was its limit. Anything faster could only be achieved by newer technology as used on the Shuttle.
 
rwessel
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 9:32 pm



Quoting Spudh (Reply 6):
Quoting Rwessel (Reply 4):
Sure it did. Right after launching off a Nimtz doing 45kts...

But seriously, no. The thermal issues alone would make it impossible.

3rd October 1967, X-15-A2 piloted by Captain William J. Knight reached a maximum altitude of 102,100ft, levelled off and accelerated to Mach 6.7 (4,520) a new world record (still is I believe) for 'conventional' flight. The airframe reached 2,700 deg F. The aircraft barely survived but was so badly damaged that it was uneconomical to repair and never flew again. The X-15 used an ablataive coating and this speed was its limit. Anything faster could only be achieved by newer technology as used on the Shuttle.

I was commenting on the SR-71, not the X-15.
 
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spudh
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RE: Did The SR-71 Go Mach 7?

Fri Oct 16, 2009 9:44 pm



Quoting Rwessel (Reply 7):
I was commenting on the SR-71, not the X-15.

Oops, sorry about that, yeah you're right there. Although I'm sure it was a bit faster than its quoted max. I think its quoted at cruise Mach 3.2 with max at 3.3 but like a lot of stats this is probably an operational limit rather than structural. I'd bet if they needed to they could dash a good bit more out of it.
I think I remember reading somewhere that it was the shock cones on the engine inlets were the limiting factor. Can't remember the 'unofficial' figure though, something like 3.6 but not sure.
 
PC12Fan
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 12:04 am

Funny story. Friend of a friend was talking to an SR-71 pilot and was asking him about the "actual" top speed of this aircraft. He'd keep pestering him saying, "no really, has fast can this thing really go". He kept after him, and after several tries the pilot barked at him finally saying, "look, I can't tell, you ok?!?!!!!"

My bet is 3.5+ unofficially.
Just when I think you've said the stupidest thing ever, you keep talkin'!
 
HaveBlue
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 12:26 am

The one thing I remember distinctly is that when a Sled driver was asked what we would do if the Russians took back the speed record, his comment was "well then we'd go up and press a lil harder on the gas pedal" or something to that effect. It's clear that it could go at least a bit faster than has been acknowledged, and there surely is a difference between operational top speeds and absolute. Also there has to be some reason the real stats are still classified and will be for many more years, I think til around 2021. If it's not any faster than already known, why the hush hush?  Wink
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BMI727
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 4:57 am



Quoting HaveBlue (Reply 10):
It's clear that it could go at least a bit faster than has been acknowledged, and there surely is a difference between operational top speeds and absolute.

That is the case with most performance data on most military aircraft.

I do remember from a TV show that the SR-71 had the distinction of being shot at (unsuccessfully) by the Egyptians and Israelis during the same mission.
Why do Aerospace Engineering students have to turn things in on time?
 
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cpd
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 5:02 am

Quoting Liedetectors (Thread starter):
I saw once on a show on TV that an SR-71 pilot stated they flew the SR-71 to Mach 7. I only thought it went to Mach 3.3. Can anyone verify/heard of this?

The highest speed known is somewhere slightly above Mach 3.5 (but probably below M4.0).

M3.5 is a number that was put in writing, done on a mission over Libya with quite a bit of hostile attention focused on the plane at that point. Of course, that could be all made up as well - though it seems realistic enough.

It would be easy enough to verify, just ask the people who were tracking Mr Shul and Mr Watson on that flight and trying so desperately to shoot them down.   Far from being stealth, it was a huge target - except that it flew so fast that it was hard to shoot down.

Quoting PC12Fan (Reply 9):

My bet is 3.5+ unofficially.

I think that's right as well.

[Edited 2009-10-16 22:03:15 by cpd]
 
BMI727
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 5:47 am



Quoting Cpd (Reply 12):
Far from being stealth, it was a huge target

The TV shows like to point out that the SR-71 included stealth features, which it did. It included the chines, canted tails, and RAM. Of course it was very far from being invisible, and really it is quite difficult to hide anything going at Mach 3 due to the large IR signature. That said, many later aircraft benefited from the early stealth features on the SR-71.
Why do Aerospace Engineering students have to turn things in on time?
 
rwessel
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 6:20 am



Quoting PC12Fan (Reply 9):
My bet is 3.5+ unofficially.

I'd guess a little past M3.5 too, although you're going to get into the region where you're going to do some damage to the aircraft with any length of exposure to those conditions.

Quoting Cpd (Reply 12):
Far from being stealth, it was a huge target - except that it flew so fast that it was hard to shoot down.

The SR-71 appears to be reasonably stealthy (although not by modern "stealth" standards) from the front, and a huge target from the rear.

The problem is that at altitude, if you can't lock on until the SR-71 is almost at your position (because it's stealthy on its approach), your SAM will run out of gas before it can catch up, since it’s starting a dozen nm below, even if it you managed to launch as the SR-71 passed overhead.
 
MadameConcorde
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 1:34 pm



Quoting BMI727 (Reply 11):
That is the case with most performance data on most military aircraft.

André Turcat told me - on a private visit a few years back - that during test flights he had pushed Concorde to maximum speeds much faster than the speed we know as Concorde's normal cuise speed (Mach 2.02) during test flights at Mach2.5 and up. He even barrel rolled Concorde in both directions. He said that during a test flight he stopped the 4 engines in the middle of flight. That last one I would never wanted to be on board. This is taking big risk but I am sure AT knew what he was doing.
The man was fearless.
There was a better way to fly it was called Concorde
 
nomadd22
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 6:08 pm



Quoting Rwessel (Reply 14):
Quoting Cpd (Reply 12):
Far from being stealth, it was a huge target - except that it flew so fast that it was hard to shoot down.

The SR-71 appears to be reasonably stealthy (although not by modern "stealth" standards) from the front, and a huge target from the rear.

The problem is that at altitude, if you can't lock on until the SR-71 is almost at your position (because it's stealthy on its approach), your SAM will run out of gas before it can catch up, since it’s starting a dozen nm below, even if it you managed to launch as the SR-71 passed overhead.

Neither was the primary reason the plane was so hard to shoot down. SAM 5s and MIG 25s both had the ability to lock on the plane and reach the the altitude. What they didn't have was control surfaces that worked at much over 70,000 feet. It was the same with the U2. The Soviets finally got Powers by shooting barrages of SAMs in the hope that one would happen to be close enough to get the target. The idiot SOB Macnamara refusing to change flight paths helped.
Anon
 
HaveBlue
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 7:17 pm



Quoting Nomadd22 (Reply 16):
The idiot SOB Macnamara refusing to change flight paths helped.

The list of what he did that makes my blood boil lengthens.
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BMI727
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 8:20 pm



Quoting Nomadd22 (Reply 16):
The Soviets finally got Powers by shooting barrages of SAMs in the hope that one would happen to be close enough to get the target.

It took fouteen missiles and they got one of their own MiG-19s in the process.

Quoting Nomadd22 (Reply 16):
The idiot SOB Macnamara refusing to change flight paths helped.

The same thing contributed to the loss of an F-16 over Bosnia and the F-117 over Serbia.
Why do Aerospace Engineering students have to turn things in on time?
 
ferrypilot
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RE: Did The SR-71 Go Mach 7?

Sat Oct 17, 2009 9:10 pm



Quoting MadameConcorde (Reply 15):
He even barrel rolled Concorde in both directions. He said that during a test flight he stopped the 4 engines in the middle of flight. That last one I would never wanted to be on board. This is taking big risk but I am sure AT knew what he was doing.
The man was fearless.

I doubt those things were officially condoned!
Sometimes a man can believe in himself too much and even a test pilot can have too much arrogance for his own good. Having said that a barrel roll can be acheived fairly easily in many aircraft types. ...I had a relative who was reputed to have barrel rolled a Lancaster Bomber.
 
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Stitch
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RE: Did The SR-71 Go Mach 7?

Sun Oct 18, 2009 2:15 am

Tex Johnson did it ( a barrel role) in the Boeing Dash 80 over Lake Washington during Seafair.

I imagine Turcat didn't keep the Concorde beyond Mach 2.2 for long due to airframe heating issues.

As for the SR-71, I have heard rumors it could reach Mach 4, but no Sled Driver I have spoken to has ever broken OpSec on the true top speed.
 
nomadd22
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RE: Did The SR-71 Go Mach 7?

Sun Oct 18, 2009 3:54 am

The skin on the 71 wrinkled pretty bad with any time beyond 3.2. They'd have to iron it back down after the flight. If it went any faster than that, I'm not sure if it would have been for long.
The A-12 might have been a better subject for the thread anyhow. I'd always heard that it was a tiny bit faster than the SR-71. But, they's all Blackboids.
Anon
 
MadameConcorde
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RE: Did The SR-71 Go Mach 7?

Sun Oct 18, 2009 7:59 am



Quoting Ferrypilot (Reply 19):
I doubt those things were officially condoned!
Sometimes a man can believe in himself too much and even a test pilot can have too much arrogance for his own good. Having said that a barrel roll can be acheived fairly easily in many aircraft types.

Turcat was not the only test pilot to barrel roll Concorde.
Second Chief test pilot Jean Franchi barrel rolled the aircraft and not only one time.

Listen to BA Concorde Captain Brian Walpole here at 2.55 in the video.

http://www.youtube.com/watch?v=KYQS3qAIjAo
There was a better way to fly it was called Concorde
 
ferrypilot
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RE: Did The SR-71 Go Mach 7?

Sun Oct 18, 2009 11:26 pm



Quoting MadameConcorde (Reply 22):
Listen to BA Concorde Captain Brian Walpole here at 2.55 in the video.

Very cool video and well worth checking out. ...The BA pilots assertion that they had raised the nose a mere 10degrees to accomplish the Barrel Roll implies in itself that Concorde could be rolled very easily.

...I have always thought that Concorde vies with the Supermarine Spitfire for the top spot as the most beautiful flying machine ever created.
 
474218
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 12:43 am



Quoting Nomadd22 (Reply 21):
The skin on the 71 wrinkled pretty bad with any time beyond 3.2. They'd have to iron it back down after the flight. If it went any faster than that, I'm not sure if it would have been for long.

The skin on the SR-71 did not wrinkle in flight, so there was no need to iron back down after flight.

The skin of the SR-71 was corrugated (from the factory).
 
HaveBlue
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 1:12 am

Quoting Ferrypilot (Reply 23):
...I have always thought that Concorde vies with the Supermarine Spitfire for the top spot as the most beautiful flying machine ever created

On the top of that list for me is the North American XB-70 Valkyrie, which I always thought was a bit like a Concorde on steroids. A formation flight of the XB-70 in front with a Concorde and a Tu-144 off each wing and slightly behind would make an awesome photo op... if any of them were still flying lol. Or the An-225 with a C-5 and An-124 same formation or our swing planes the B-1 with an F-14 and F-111 off each wing... just dreaming.  

http://img4.imageshack.us/img4/8767/xb70inflight.jpg
[Edited 2009-10-18 18:14:49]
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Flighty
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 1:36 am



Quoting HaveBlue (Reply 25):
A formation flight of the XB-70 in front with a Concorde and a Tu-144 off each wing and slightly behind would make an awesome photo op... if any of them were still flying lol.

Like landing on the moon, those 3 aircraft were amazing achievements for their time!
 
747400sp
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 2:20 am



Quoting HaveBlue (Reply 25):
An-225 with a C-5 and An-124 same formation.


[Edited 2009-10-18 18:14:49]

This could still happen.

I would like to see all of the world largest jets in formation. For example a 747, C-5, An-124, A380 and An-225 all flying in formation.  Smile Man the wake that would cause.  laughing 
 
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vzlet
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 11:14 am



Quoting Nomadd22 (Reply 16):
The idiot SOB Macnamara refusing to change flight paths helped

Blame MacNamara for many things, but as an executive at the Ford Motor Company at the time, he wouldn't have had much influence on the routing of U-2 overflights of the USSR.
"That's so stupid! If they're so secret, why are they out where everyone can see them?" - my kid
 
nomadd22
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 12:02 pm



Quoting 474218 (Reply 24):

The skin on the SR-71 did not wrinkle in flight, so there was no need to iron back down after flight.

You might want to read Ben Rich's book. One new pilot declared an emergency on his first flight because he was unaware of the effect.
Anon
 
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vzlet
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 12:15 pm



Quoting Nomadd22 (Reply 29):
You might want to read Ben Rich's book. One new pilot declared an emergency on his first flight because he was unaware of the effect.

Does the book say how the pilot detected the wrinkles? I wouldn't think that much, if any, of the skin is visible from the cockpit, especially when wearing a pressure helmet.

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474218
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 1:54 pm



Quoting Nomadd22 (Reply 29):
You might want to read Ben Rich's book. One new pilot declared an emergency on his first flight because he was unaware of the effect.

I didn't have to read Ben's book. I worked in the 9th FMS Sheet Metal Shop from 1966 to 1969 and if the skin had wrinkled we would have been the ones to fix it. The skins cracked and they delaminated and some times the wing to fuselage fairings (called fillets) would just fall off, but I never saw the skin wrinkle.
 
nomadd22
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 3:33 pm



Quoting Vzlet (Reply 30):
Does the book say how the pilot detected the wrinkles? I wouldn't think that much, if any, of the skin is visible from the cockpit, especially when wearing a pressure helmet.

This is the excerpt.
I remember when a new pilot flying the SR-71 for the first time
out of Beale [AFB, near Sacramento] began shouting "Mayday,
Mayday" over Salt Lake City. "My nose is coming off!" My God,
we all panicked and cranked out all the emergency vehicles. The
guy aborted, staggered back to Beale. All that really happened
was that the airplane's nose wrinkled from the heat. The skin
always did that. The crew smoothed it out using a blowtorch. It
was just like ironing a shirt.
Anon
 
474218
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 4:38 pm



Quoting Nomadd22 (Reply 32):
This is the excerpt.
I remember when a new pilot flying the SR-71 for the first time
out of Beale [AFB, near Sacramento] began shouting "Mayday,
Mayday" over Salt Lake City. "My nose is coming off!" My God,
we all panicked and cranked out all the emergency vehicles. The
guy aborted, staggered back to Beale. All that really happened
was that the airplane's nose wrinkled from the heat. The skin
always did that. The crew smoothed it out using a blowtorch. It
was just like ironing a shirt.

Nice story but didn't happen when I was there. I am not sure the pilot can even see the nose of the aircraft.
 
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vzlet
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 9:06 pm



Quoting Nomadd22 (Reply 32):
This is the excerpt.

Thanks for looking it up. Is that Ben Rich speaking, or someone else's words? It sounds a little "urban legendy" to me, but if it's Rich relating an incident, I certainly will quibble no more.

-Mark
"That's so stupid! If they're so secret, why are they out where everyone can see them?" - my kid
 
nomadd22
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 10:11 pm



Quoting Vzlet (Reply 34):
Thanks for looking it up. Is that Ben Rich speaking, or someone else's words? It sounds a little "urban legendy" to me, but if it's Rich relating an incident, I certainly will quibble no more.

It was One of the "Other voices" Ben used. Colonel Jim Wadkins, one of the pilots, was the one quoted. Page 243 if you have the book.
Can't say it made that much sense to me either, but I'd assumed it wouldn't have been in the book if he made it up. That's not saying I'd bet my retirement on it.
Anon
 
474218
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RE: Did The SR-71 Go Mach 7?

Mon Oct 19, 2009 11:38 pm



Quoting Nomadd22 (Reply 35):
It was One of the "Other voices" Ben used. Colonel Jim Wadkins, one of the pilots, was the one quoted. Page 243 if you have the book.

One thing about the SR-71 (and other Blackbirds) the record keeping was second to none. So it only took a couple of clicks of the mouse to see that no pilot named Wadkins ever flew the SR-71.

However, there were two pilots named Watkins and Maj. Jim L. Watkins was one. He first flew the SR-71 on 17 Feb 1967.

I remember an incident about this time that may have been what Mr. Rich was thinking of. Just forward of the cockpit windscreen is a small flush mounted antenna. Prior to flight this antenna had been removed and when it was reinstalled the screws were not tightened. During the flight the antenna started to vibrate and flutter, right in front of the pilot. The mission was aborted. Needless to say the antenna was wrinkled but it was not from heat.
 
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cpd
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RE: Did The SR-71 Go Mach 7?

Tue Oct 20, 2009 4:49 am

Quoting 474218 (Reply 24):
The skin on the SR-71 did not wrinkle in flight, so there was no need to iron back down after flight.

The story goes that one had an accident. It was damaged badly enough that it couldn't be repaired. So the bits were cut up, and the plan was to burn the lot so it wouldn't be recognisable.

Well, a huge fire ensued. Once it stopped, the result was paint burnt off, but otherwise, bits and pieces, with some slight wrinkles still obviously from an SR-71, and mostly unaffected.

In the end, they reportedly gave up and buried the lot. It's probably still there.

Quoting Vzlet (Reply 30):
I wouldn't think that much, if any, of the skin is visible from the cockpit, especially when wearing a pressure helmet.

My thoughts too. The big bone-dome didn't appear to afford much visibility at all. The plane itself didn't have much visibility either, hence the RSO sometimes using the view-scope on approaches to land in poor weather as a sort of a help to the pilot.

Quoting Nomadd22 (Reply 16):
Neither was the primary reason the plane was so hard to shoot down.

But the major, and most obvious reason - is that at those speeds, even a change of direction by only a few degrees would destroy the solution of the missile.

Quoting MadameConcorde (Reply 15):
André Turcat told me - on a private visit a few years back - that during test flights he had pushed Concorde to maximum speeds much faster than the speed we know as Concorde's normal cuise speed (Mach 2.02) during test flights at Mach2.5 and up.

The man has done many things (he's a legend), and while I wouldn't doubt him, I do wonder how he managed that, given that they just managed 2.23 in Concorde 02, and then later 2.19 or 2.21 in Concorde 202 Delta-Golf (if I remember right). 202 if I'm not mistaken had engine surge at that point, so they eased off.

I seriously doubt anything more than M2.3 would ever have been achieved in Concorde without engine problems. I don't doubt that the airframe might have survived, especially if the ISA was very suitable, it's the engines/intakes that I think wouldn't handle it.

I do believe the talk of barrel rolls and other unconventional maneuvers. Even though it was all "off the record".

Quoting Stitch (Reply 20):
I imagine Turcat didn't keep the Concorde beyond Mach 2.2 for long due to airframe heating issues.

02 did M2.23 during engine intake trials, and 202 (the production model) did 2.19 or 2.21 (if memory serves me right).

Airframe heating issues were not likely the problem, especially in very cold conditions. The TMO (for production models carrying passengers) might well be 127C, but they did go beyond that on numerous occasions, sometimes with the engines surging - before anything more than M2.3 was known to have been achieved. The TMO, in most conditions had some margin before it was achieved. Though it may well be achieved in warm conditions at speeds less than M2.0. By warm, we are talking much higher than ISA.

Hence, the production models had a cruise rating that would, if necessary, reduce the engine performance (by about 1% N2) if needed. In very cold conditions, this would occur. Normally, the swap between engine ratings would have no change at all, so the N2 would remain as it was. So as you can well imagine, going faster than M2.02 was possible, even though operational procedures (and the AFCS Max Climb/Max Cruise mode) in civilian service didn't allow it.

It is also well known that it also flew much higher in testing than the delivered planes carrying passengers did. Of course, they had their FL600 limit, but pre-production models (which in this context, I mean 01, 02, 201, 202), but it was known to have achieved almost FL640, and, on another occasion, one achieved almost FL690.

[Edited 2009-10-19 22:15:56 by cpd]
 
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Stitch
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RE: Did The SR-71 Go Mach 7?

Tue Oct 20, 2009 2:02 pm



Quoting Cpd (Reply 37):
Airframe heating issues were not likely the problem, especially in very cold conditions.

For a short time, I agree. But the plane was designed with a cruise speed of Mach 2.2 due to airframe heating limits and in operation generally cruised at Mach 2 in part to reduce the thermal load to increase airframe life. So if the plane could reach and maintain Mach 2.5, I would not expect Monsieur Turcat to cruise at that speed for an extended period of time (say 60 minutes or more).
 
474218
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RE: Did The SR-71 Go Mach 7?

Tue Oct 20, 2009 7:53 pm



Quoting Cpd (Reply 37):
The story goes that one had an accident. It was damaged badly enough that it couldn't be repaired. So the bits were cut up, and the plan was to burn the lot so it wouldn't be recognisable.

Well, a huge fire ensued. Once it stopped, the result was paint burnt off, but otherwise, bits and pieces, with some slight wrinkles still obviously from an SR-71, and mostly unaffected.

In the end, they reportedly gave up and buried the lot. It's probably still there.

Like I said be for it only takes a couple of clicks of the mouse to get the real story rather than repeat things you heard from people that don't know in the first place: The following web site lists all the SR-71 (and other Blackbirds) crashes and while what you say may or may not be true, I worked in the shop that would have repaired and wrinkled skins and in my limited time at Beale we never repaired any wrinkled skins. Cracks were another story, every flight resulted in many hours of structural repairs.

The crash you describe sounds like 61-17977 which is detailed on page 3 of the following site.

http://www.wvi.com/~sr71webmaster/srloss~1.htm
 
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cpd
Posts: 4595
Joined: Sat Jun 28, 2008 4:46 am

RE: Did The SR-71 Go Mach 7?

Wed Oct 21, 2009 2:22 am

Quoting 474218 (Reply 39):
Like I said be for it only takes a couple of clicks of the mouse to get the real story rather than repeat things you heard from people that don't know in the first place:

Wow, so sarcastic. I won't mention names then. It came from someone who did know. Someone who was there at the time.

Quoting 474218 (Reply 39):
The crash you describe sounds like 61-17977 which is detailed on page 3 of the following site.

No sorry, it wasn't that one. Perhaps you might be a little less abrupt next time?

[Edited 2009-10-20 19:26:33 by cpd]
 
474218
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Joined: Mon Oct 10, 2005 12:27 pm

RE: Did The SR-71 Go Mach 7?

Wed Oct 21, 2009 2:44 am

Quoting Cpd (Reply 40):
Wow, so sarcastic. I won't mention names then. It came from someone who did know. Someone who was there at the time.

I guess I am sarcastic because "I was there" and everyone else is saying "I heard, I read, I was told" will I lived it.

So I will not say anything else and you can go on believing what you want to but "I was here" and I know what happened.

[Edited 2009-10-20 19:46:42]
 
nomadd22
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Joined: Fri Feb 22, 2008 7:42 pm

RE: Did The SR-71 Go Mach 7?

Wed Oct 21, 2009 11:43 am

Thanks for the link 474218, but I'm not sure why you think it's unreasonable for people to consider the guy who worked on building the plane and took over Skunk Works from Kelly a more reliable source than an anonymous nick in a chat room. Maybe the pilot who you doubt existed because of my typo just made up those stories. Maybe some poster and reality aren't exactly the closest of buddys. I guess everyone here can make their own decision.
Anon
 
Blackprojects
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RE: Did The SR-71 Go Mach 7?

Wed Oct 21, 2009 6:21 pm

I Used to have an Aerograph book which stated that the Maximum MACH Number on the SR-71a was 3.6 due to going any faster and the the Supersonic Shock waves formed on the PITOT Tube at the tip of the nose would start to enter the Intakes of the Engines which would result in an UN-START and Probable loss of the Aircraft due to extreme Airodynamical forces!
 
aeroweanie
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RE: Did The SR-71 Go Mach 7?

Wed Oct 28, 2009 11:34 pm



Quoting PC12Fan (Reply 9):
My bet is 3.5 unofficially.

The fastest speed every achieved in a A-12/SR-71/YF-12 was M=3.6, by Darryl Greenamyer, on a test flight. The NASA handbook for people running experiments on the SR-71 has a chapter on what would be needed for the SR-71 to achieve M=4. The list is significant and not cheap.
 
prebennorholm
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RE: Did The SR-71 Go Mach 7?

Thu Oct 29, 2009 12:47 am

The SR-71 holds the world speed record at 3,529.56 km/h (which is likely to be around Mach 3.3 at the high altitude).

Check http://records.fai.org/documents.asp?from=gliding&id=8879

The X-15 does not count in the category of aeroplanes since it was unable to take off on own power.
Always keep your number of landings equal to your number of take-offs

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