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150 kts in an SR71 is more falling than flying, you can barely keep the things level even at 270. A second or two later on the throttle and it would have been a very different story.

Funny, I just read that story a few days ago. Never seen it before.

"I must have had good instructors in my flying career, as something told me I better cross-check the gauges." It's bullshit.

If he truly was 'falling' then he had stalled, and a cross-check would be unnecessary as there would be multiple stall warnings screaming in his ears and flashing in his eyes.

In a plane such as the SR71, I imagine there was a pre-stall warning as he approached stall speed too.

Relative to the attitude, yes, so they must have been flying level at about 20 degrees nose-up.

Interesting info on the subject here and here.

Fuuuuuuck. Interesting reading. Cheers for that!

I used to live with a bloke who flew these. He said that if they were scrambled (to intercept Russian bombers) they never knew if if was for real, but if it was then it was a one way trip because there'd be nothing to come back to. All rather futile.

Interesting info on the subject here and here.

I was going to ask if there was a stall warning system or stick shaker, but the info in one of the links says not. I guess that, apart from when landing, the SR-71 never got into many slow speed and/or low altitude situations!

I was going to ask if there was a stall warning system or stick shaker

No stall warning, but a stick shaker for critical angle of attack, as I read it.

And if you exceeded said angle at Mach numbers then you were fucked.

Sounds relaxing.

So based on the critical angle of attack (18 degrees), the pilot in that story above would have literally been at or just over it. He says himself "we were just falling in a slight bank", which is basically what happens at that AOA and speed, the thing just flops over with minimal input.

Ive just been messing about with it on x-plane and it seems to match all this info. It's quite fun trying to fly the thing as slow as possible.

Shit I haven't used X plane for so long. Need to install!

I seemed to understand that beyond a critical AOA it will continue to pitch up (increase AOA) with no chance of recovery? Is that what you're seeing?

I LOLd at sounds relaxing.

That's pretty much exactly what happens, it just pitches up and then goes into a backwards spin.

Sweet design.

Some SR-71 love:

http://gizmodo.com/5511236/the-thrill-of-flying-the-sr%2071-blackbird

http://www.habu.org/links.html

EXCERPT:
I can tell you about the SR-71 Blackbird's titanium frame, its Pratt&Whitney J58-P4 engines, or*its genesis. But that's not important. What really matters is the thrill of flying it in an extremely dangerous mission, as remembered by this pilot.-JDIn April 1986, following an attack on American soldiers in a Berlin disco, President Reagan ordered the bombing of Muammar Qaddafi's terrorist camps in Libya. My duty was to fly over Libya and take photos recording the damage our F-111's had inflicted. Qaddafi had established a 'line of death,' a territorial marking across the Gulf of Sidra ,swearing to shoot down any intruder that crossed the boundary.

On the morning of April 15, I rocketed past the line at 2,125 mph.I was piloting the SR-71 spy plane, the world's fastest jet, accompanied by Maj Walter Watson, the aircraft's reconnaissance systems officer (RSO). We had crossed into Libya and were approaching our final turn over the bleak desert landscape when Walter informed me that he was receiving missile launch signals. I quickly increased our speed, calculating the time it would take for the weapons-most likely SA-2 and SA-4 surface-to-air missiles capable of Mach 5 - to reach our altitude. I estimated that we could beat the rocket-powered missiles to the turn and stayed our course, betting our lives on the plane's performance.After several agonizingly long seconds, we made the turn and blasted toward the Mediterranean 'You might want to pull it back,' Walter suggested. It was then that I noticed I still had the throttles full forward. The plane was flying a mile every 1.6 seconds, well above our Mach 3.2 limit. It was the fastest we would ever fly. I pulled the throttles to idle just south of Sicily , but we still overran the refueling tanker awaiting us over Gibraltar.

Here's something I didn't know - in discussions yesterday with my old academy chums from back in Florida, someone said that one of our USAF ROTC instructors was a former SR-71 pilot Lt.Col Harry Platt. I've done some checking, and it seems that maybe he wasn't actually with the SR-71 program, but on the Apollo ARIA program instead. I'd not even known about it, but apparently it was a test program which was developed for mobile tracking of spacecraft of the Apollo program, and later. And yes, I did know Lt.Col Platt. Quiet man, and never really talked about his service days. Which for me now, is a real pity.

http://honeysucklecreek.net/other_stations/ARIA/ARIA_stories.html
http://www.angelfire.com/ma3/spacepatch/ARIA.html

The more I read about the BAC English Electric Lightning, the more awestruck I am. It's pretty amazing that the SR-71 could NOT match the Electric Lighting for maximum altitude, especially as the SR-71 was a reconnaissance aircraft, which would use height, and in its own case, speed, to evade the enemy. The SR-71's service ceiling of 85,000 feet, and certainly 87,000 feet was never exceeded. The BAC English Electric Lightning achieved 87,500 feet and 88,000 feet.

Also quite incredible, is that the English Electric Lightning had super-cruise in 1954!!! This is breaking the sound barrier WITHOUT using afterburners. The BAC EEL did this on its very first flight.

The BAC English Electric Lightning achieved 87,500 feet and 88,000 feet.

In a zoom climb. The SR-71 could fly level at 85000.

I'd written that altitude detail in the post above yours. :-)

Perhaps I needed to emphasise level.

What would the SR-71 have achieved if somebody had wanted to score bragging rights? Accelerate to M3.4 in level flight at 85,000', tilt the nose up. Given the level flight limit and speed of the Lightning, I can't see any reason why the SR-71 wouldn't have easily topped out at over 100,000'

One article I read put the max alt at 87,000 feet
http://birch.family.tripod.com/blackbird.html

But the others agree with you.
http://www.u2sr71patches.co.uk/sr71performance.htm
http://www.sr-71.org/blackbird/sr-71/

I still feel that the super cruise feature of the BAC EEL was extremely special, and a very farsighted development.
[ame]http://en.wikipedia.org/wiki/Supercruise[/ame]

super cruise feature

Was it really a "feature"? They put two big fuck off engines in a tight airframe designed to do >M2 wet, it's not that surprising that it could do >M1 dry. Bear in mind that modern fighter engines are turbofans, so they gain much more from afterburn than the relatively primitive non-by-pass Avon, e.g. about +30% for the Avon vs. +50% for the P&W F119 in the F-22.

Accelerate to M3.4 in level flight at 85,000', tilt the nose up. Given the level flight limit and speed of the Lightning, I can't see any reason why the SR-71 wouldn't have easily topped out at over 100,000'

From one of the links I posted previously...

As Angle of Attack increased, the aircraft reached a point where it departed from controlled flight rather than stalling out. A nose-up pitching moment developed as the AOA increased, which eventually becomes uncontrollable as the the critical AOA was reached. Subsonic, the critical AOA for pitch-up is approximately 18 degrees. At high Mach cruise, extreme caution was necessary if Habus were flying at altitudes above those for optimum supersonic cruise because the AOA could exceed 7-8 degrees. At 7 to 8 degrees AOA, any pitch transients caused by unstarts, increased bank angles, etc., could easily lead to an uncontrolled pitch-up manoeuvre.
I think it's fair to assume that when doing mach 3.4 at 85,000', pulling back on the stick wasn't considered a very good idea.

7 - 8 fucking degrees??? I missed that bit... Jesus, I'd leave the stick well alone at that speed. I can barely maintain a constant AOA at 90 knots.