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Mach 3.5 Over Libya in an SR-71 Blackbird

thesr71blackbird.com

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Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#101

Post by ckozlowski »

smburdick wrote: post #49
ben7799 wrote: post #45

Earlier quoted context omitted.

Which is really odd, as Titanium is not that rare. Are we sure that story about the Titanium coming from the USSR is accurate?

I think it's mostly anecdotal (I have heard it too, but I can't think of where) Not a metallurgist, but if I had to guess it was hard to find in large enough quantities at the time. I also understand that it's a lot harder to work with than say aluminum or steel Speaking of which, King Louis served his guests with aluminum silverware, since at the time it was more valuable than gold due to the difficulty of extractin…

"Skunk Works" by Ben Rich is a first hand account by the (eventual) lead of that Lockheed division, and he describes this in his book.

https://www.amazon.com/Skunk-Works-Personal-Memoir-Lockheed/...

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#102

Post by ckozlowski »

scrlk wrote: post #7
ubermonkey wrote: post #5

Earlier quoted context omitted.

I have read that story SO MANY TIMES, but I nearly always click and read again when it comes up.

Once you've finished re-reading, here's the reverse version: > There were a lot of things we couldn't do in a Cessna 172, but we were some of the slowest guys on the block and loved reminding our fellow aviators of this fact. People often asked us if, because of this fact, it was fun to fly the 172. Fun would not be the first word I would use to describe flying this plane. Mundane, maybe. Even boring at times. But th…

On the Blackbird site, there's a really good factual story delivered after someone asked about the slowest they'd ever flown the plane. That tale is a good read:

https://www.thesr71blackbird.com/Aircraft/Stories/sr-71-blac...

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#103

Post by CircleSpokes »

4gotunameagain wrote: post #94
CircleSpokes wrote: post #81

Earlier quoted context omitted.

What a ridiculous thing to say. Do you think the Libyan intelligence service gets to bomb dance clubs and then cry sovereignty when someone bombs some military targets in Libya? I don't know if you are ignorant of the situation or if you truly believe a country cannot retaliate against an attack against their citizens and allies. (This story and the bombing campaigned being photographed by the SR71 was a direct respo…

Well, nobody presented evidence that Libya was behind the La Belle bombing. If you think that some shady arm of US intelligence isn't capable of such a heinous false flag operation, I urge you to read more history. Now I'm not saying it was one, I'm saying we have no idea who was behind it.

Because real life isn't a TV show. That isn't how national security agencies work. They don't dump raw intelligence to the public. The US knew it was Libya obviously, and the data released since then has proved that. Hell even the Stasi & the soviets knew it was Libya.

Again this isn't a TV show. No country needs permission to react to an attack against them by another state like Libya.

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#104

Post by Fatnino »

bombcar wrote: post #86
geocrasher wrote: post #25

Indeed, Mach 3.5 is the declared top speed in this story, but higher speeds are implied. The Mach eases to 3.5 as we crest 80,000 feet... Screaming past Tripoli, our phenomenal speed continues to rise... I realize that I still have my left hand full-forward and we're continuing to rocket along in maximum afterburner... The TDI now shows us Mach numbers, not only new to our experience but flat out scary. He mentions u…

> It's truly incredible that the A12/SR-71 aircraft was designed without the benefit of modern computing. One of the huge things that computers give us is the ability to simulate where the design limits actually are - you can "relatively" easily design a device that needs to do "at least X" but once you're done, you don't really know how far past X you can go - computer simulations can help discover where and what ex…

The computer allows you to cut down your design so that it will do "at least X and no more" so you can save a few cents and then the plane falls apart when the pilot asks it to do Mach 3.6 but that's OK because the manual said it will top out at 3.5

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#106

Post by kingkongjaffa »

sbaiddn wrote: post #89
kingkongjaffa wrote: post #72

Earlier quoted context omitted.

It’s a nice story to read about rock star engineers but F1 race car aerodynamics is not done on paper. Sure concepts to try can be sketched out on paper. Things like wing arrangements, rough intuitive ideas about where the clean and dirty air is. But everything in F1 is an iterative loop between a lap time simulation, vehicle dynamics, and aerodynamics. Vehicle performance is largely a trade off between Cornering dyn…

Obviously they use computers. My point is that Newley, (claims at least) to do his design work on paper. Which, is not that surprising. If you're good enough to have a draughtman digitize your designs for you, you're free to draw what you want on a five by four foot surface and not fiddle with a GUI and a 30?, 40? inch screen. Overnight they print you the latest drawing on the plotter and you're back to you doing you…

His name is Newey BTW.

What you're describing is not how engineering is done.

There's no overnight printing of the drawings.

The 3D CAD models are designed and available in real time, they are used in various CFD and FEA models. The only time drawings are printed out are dimensioned production drawings sent to manufacture the parts.

https://fractory.com/engineering-drawing-basics/

There are no digital draftsmen, it's sort of semantics but design engineers are working directly with parametric 3D models, they can produce 2D drawings from the models.

As a senior engineer Newey is likely reviewing Wind tunnel data, CAD designs of concepts, CFD/FEA Data, laptime sim results, and collaborating "over the shoulder" of less senior engineers responsible for specific aerodynamic packages, who then feed that info in collaboration with design engineers and surface modelers to update the CAD models.

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#107

Post by ridgeguy »

geocrasher wrote: post #25

Indeed, Mach 3.5 is the declared top speed in this story, but higher speeds are implied. The Mach eases to 3.5 as we crest 80,000 feet... Screaming past Tripoli, our phenomenal speed continues to rise... I realize that I still have my left hand full-forward and we're continuing to rocket along in maximum afterburner... The TDI now shows us Mach numbers, not only new to our experience but flat out scary. He mentions u…

Second the recommendation Ben Rich's "Skunk Works" as a good read. A fascinating tale of hardware development in an earlier age.

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#108

Post by ridgeguy »

AdamN wrote: post #61
cm2187 wrote: post #56

Earlier quoted context omitted.

Temperature is the limiting factor for speed, I remember SR71 pilots on a panel saying the aircraft flew faster in winter than in the summer for that reason.

It's also cool that the whole thing was machined 'loose' so that it would expand as it heated up. Apparently the plane would leak fuel and oil when it was on the ground ...

Yep, JP-7 [1]. Special low vapor pressure to mitigate accidental ignition hazard.

The Sled leaked like a grad student's '69 VW bus in the hangar. Leak-free above > 1.5 Mach.

(edit to add link)

[1] https://en.wikipedia.org/wiki/JP-7

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#109

Post by greggsy »

brightball wrote: post #37
greggsy wrote: post #35

Earlier quoted context omitted.

“The Navy told us that a Chinese satellite turned and headed on a different route to photograph that plane.” I can only assume that China publish their targeting on some Twitter account? What ludicrous statement.

I don't think the Navy was watching Chinese twitter...

Are you implying that they disclosed (to a movie director) that the USA have a foothold within China’s IMINT apparatus?

It’s trivial to observe flyover changes, but it’s ludicrous to suggest that this action alone meant they were looking for a specific aircraft.

Re: Mach 3.5 Over Libya in an SR-71 Blackbird

#110

Post by rocket_surgeron »

mardifoufs wrote: post #14

I love stories about America violating sovreign airspace, especially when they use such a cool plane. The entire world is truly their own backyard!

The SR-71s were over Libya in 1986 because the Libyan secret service detonated a bomb in a Berlin nightclub, killing 3 and wounding hundreds, ten days prior.

"oh yeah well what abou.."

With all due respect, stop.

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