15 ms·

The SR-71 Spy Plane Was So Fast, It Outran Every Missile Fired at It

188 points by jrs235 8y ago

misthop 8y ago
To me the most interesting part of this article is that I missed there was a contract awarded for a Mach 6 SR-72, that may or may not already have a sighted test platform.
rootbear 8y ago
A friend of mine served in the Air Force on the refueling planes that serviced the SR-71s. He said that it was hard for the refueling plane to go as fast as the SR-71's slowest speed! So they did the refueling in a shallow dive, to give the refueling plane a boost.
areoform 8y ago
Is there any single piece of technology that's more retro-futuristic than the SR-71? It is undefinably iconic especially if you understand what happened behind the scenes. Lockheed's Skunk Works managed to not only look into the future, but they managed to make it manifest in the past. The first one took flight over fifty years ago and we still talk about it as if they represent the promise of the future. As a culture and community, we rarely view Project Apollo in the same way. To me, in contrast to the Blackbird, our first step outside our cradle looks dated. The Saturn V is an ode to the sheer force of will required to send human beings to another heavenly body. It certainly looks the part. The Blackbirds, on the other hand, were precise, surgical instruments designed to cut borders and they look the part. Every element of the plane ends in that sharp-looking edge. There are no blunt surfaces on it. It’s one complex curve wrapped around itself and stretched into that timeless shape. And that's before you pull back on the curtain. I don't have online sources for this, but I have read books about the project that explained how every single part within the Blackbirds - from the engines to the paint - was brought into being for this project. They set out to do something so daring and so pioneering that they had to invent new alloys to do it. And then they had to build the machines to work that alloy: new machines - tape-based robots - to precisely carve it into shape, new procedures to put it together, and new philosophies to let it fly. These planes were designed to fly so fast that ordinary Titanium-based alloys would melt or weaken over time leading to rapid, unplanned disassembly. They didn’t have more advanced ceramics which could do the job, so Kelly Johnson’s team came up with a new alloy that was annealed - or re-tempered - in flight, so that it became stronger and stronger over time. Theoretically above some classified altitude the Blackbird can go much faster than Mach 3 and keep on going until the airframe melts away at some crazy high, theoretical speed no one has bothered to check. They did all of that in a past where the most sophisticated engineering tool in common use was a slide rule and the first scientific pocket calculator was nearly a decade into the future. Do you ever wonder when we'll build something so daring that it will finally eclipse this project? I do. Paraphrasing Thiel, "what happened to the future? We were promised Blackbirds and got the F-35 instead."
- blattimwind 8y ago
  > Paraphrasing Thiel, "what happened to the future? We were promised Blackbirds and got the F-35 instead." It's kinda weird how the F-35 just looks somehow dated and like a slob compared to e.g. the older (and cooler looking) F-22. Though perhaps "cool looks" is maybe not the prime factor in fighter jet selection...
  - combatentropy 8y ago
    Kelly Johnson, who led the project to build the Blackbird, disagrees. "All of us had been trained by Kelly Johnson and believed fanatically in his insistence that an airplane that looked beautiful would fly the same way." --- Ben Rich, Skunk Works This quote opens an essay on beauty by Paul Graham, http://www.paulgraham.com/taste.html http://www.paulgraham.com/taste.html
    - js2 8y ago
      Function follows form?
      - ReptileMan 8y ago
        They merge at a point. The moment they merge you have achieved Nir... Unix ideal.
    - mixmastamyk 8y ago
      Believe he also had to be convinced by Rich to support the boxy F-117A.
      - Teknoman117 8y ago
        The F-117 was mostly a limitation of computing technologies at the time. We (apparently) didn't have the horsepower to model radar hitting curved surfaces, so the boxy plane came as a result of the limitations of the modelling system.
  - 8y ago
SEJeff 8y ago
There is an unbelievably good interview with Brian Shul, one of the only SR-71 pilots to take a bunch of pictures of the plane[1]. He tells the story about when his commander asks him to fly right up to the soviet border to get their anti-air radars to light the blackbird up. He asked what he should do if they shot missiles at it and his commander said to just turn around and outrun it. He was quite skeptical of this and very amusingly describes this real life encounter. He's a really funny speaker. [1] https://www.youtube.com/watch?v=BZRP1q1PGUk&t=33m0s https://www.youtube.com/watch?v=BZRP1q1PGUk&t=33m0s UPDATE: Video with better sound thanks to https://news.ycombinator.com/item?id=19505767 https://news.ycombinator.com/item?id=19505767 I found the specific story I was referring to at 33m
- WestCoastJustin 8y ago
  +∞. I watch this anytime I need motivation. This guy is the epitome of not letting anything get in his way. Such a good public speaker and amazing career! Cannot upvote that video enough. Here's one with better sound: https://www.youtube.com/watch?v=BZRP1q1PGUk https://www.youtube.com/watch?v=BZRP1q1PGUk
  - SEJeff 8y ago
    Thanks updated! (33m0s is the story I was referring to)
jclay 8y ago
The SR-71 flight manual can also be found here [0]. I was surprised to find the plane can be flown solo [1], and with no pressure suit below 50,000 feet [2]. There is also a section on "Tactical Limits" describing scenarios where exceeding normal operating limits is advised to exit a hostile area [3] 0. https://www.sr-71.org/blackbird/manual/ https://www.sr-71.org/blackbird/manual/ 1. https://www.sr-71.org/blackbird/manual/5/5-23.php https://www.sr-71.org/blackbird/manual/5/5-23.php 2. https://www.sr-71.org/blackbird/manual/5/5-23.php https://www.sr-71.org/blackbird/manual/5/5-23.php 3. https://www.sr-71.org/blackbird/manual/3/3-135.php https://www.sr-71.org/blackbird/manual/3/3-135.php
- darkpuma 8y ago
  > I was surprised to find the plane can be flown solo [1], Doubtlessly a consequence of the A-12 being flown solo. The SR-71 was a derivative of the A-12.
- CompelTechnic 8y ago
  Link [3] is hilarious in how banal it is- the same of the manual describes both how to defog your windows and how to GTFO if under hostile missile fire.
UI_at_80x24 8y ago
My favorite story about the Blackbird is how it was designed with heat and expansion in mind. On the ground to leaked fuel like a sieve[1][2], it was only once it reached operational speed that the joints & frame heated up and sealed it, (thus requiring a refueling shortly after take-off). [1] https://www.sr-71.org/blackbird/sr-71/ https://www.sr-71.org/blackbird/sr-71/ [2] http://physicsbuzz.physicscentral.com/2011/02/betrayed-by-heat-sr-71-blackbird.html http://physicsbuzz.physicscentral.com/2011/02/betrayed-by-he...
- rootbear 8y ago
  The ground crews, I'm told, hated this plane because it leaked toxic fuel everywhere while on the ground and was otherwise a pain to deal with. These sorts of stories are what impress me about programs like this. No commercial product could ever be so expensive, so difficult, so wildly impractical. The military are practically the only ones who can do things like this, because the need is so great it justifies all the craziness. I work at NASA and we do crazy things like sending robots to Mars, but that seems tame compared to the insanity of something like the SR-71.
- Teknoman117 8y ago
  The other major reasons they didn't load much fuel on the ground is that the engine fuel economy at low speeds and low altitudes was atrocious. After refueling, the crews would head for the cruising altitude as soon as possible.
deepnotderp 8y ago
I don't know the full veracity of this piece, but IIRC the Foxbat once acquired a lock on it: https://theaviationist.com/2013/12/11/sr-71-vs-mig-31/ https://theaviationist.com/2013/12/11/sr-71-vs-mig-31/
- ceejayoz 8y ago
  Plenty of things acquired a lock on it, including ground-based SAM sites. That's the easy part.
  - adolph 8y ago
    The USSR pilot claims: “Had the spy plane violated Soviet airspace, a live missile launch would have been carried out. There was no practically chance the aircraft could avoid an R-33 missile.”
    - ceejayoz 8y ago
      The pilot also claims the lock was from 120km, which is the maximum range of the R-33 at the time, so I'm a bit dubious of the idea without a practical demonstration. I do suspect the "surround from all directions" approach detailed later would've worked, but that's why we moved off to stealth and satellites.
    - deleted 8y ago
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  - deleted 8y ago
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combatentropy 8y ago
I think there is a lesson here that applies to more than just planes. Speed often can solve a problem in a simple way. The enemy will fire missiles at us. What shall we do? (1) Invent missile-proof armor, (2) Build computer-guided anti-missile lasers, (3) Just fly really fast. I guess all of those are hard to do. Making the SR-71 fly at Mach 3 wasn't easy. But to me it seems more elegant. In the early 2000s, Google made a big deal about speed in web apps. I think it still does, but I don't hear about it anymore. And everybody knows that GMail is slower. But I appreciated it while it lasted.
- guhidalg 8y ago
  This resonates with how I like to solve problems. Instead of thinking about how we can fix it or mitigate it, how can we make it impossible for a certain kind of problem to occur? Maybe it's just my procrastination speaking but I find it easier to just wipe out entire kinds of issues.
andy_adams 8y ago
I don't know much about aviation, but I know there's a plane that was faster than the SR-71: The X-15 [1]. I know because my great uncle died flying the X-15 on an experimental flight [2], so it's always been an interesting story for my family. [1] https://en.wikipedia.org/wiki/North_American_X-15 https://en.wikipedia.org/wiki/North_American_X-15 [2] https://theaviationgeekclub.com/the-story-of-mike-adams-the-only-pilot-to-lose-his-life-during-the-x-15-flight-test-program/ https://theaviationgeekclub.com/the-story-of-mike-adams-the-...
- mr_overalls 8y ago
  I find it absolutely incredible that the piloted speed record set by this aircraft - set in October 1967 when William J. Knight flew Mach 6.7 - hasn't been broken in 50+ years.
  - rtkwe 8y ago
    It's a mix of things I think. First we haven't had a really big breakthrough in engine technology in a while and second there's no need to risk a person piloting these anymore because computers and remote control tech has gotten good enough.
    - ProAm 8y ago
      Wouldnt the scramjet engines be a pretty big breakthrough?
      - dmoy 8y ago
        Scramjet still needs air though, doesn't it? Thus it has to fly lower, and maybe can't get as fast as a rocket engine. Scramjet planes are faster than other non-rocket planes I would imagine?
        darkpuma 8y ago
        The SR-71 cruised at Mach 3.2. Scramjets have been demonstrated to do Mach >5, and theoretically might be capable of something between Mach 17 to Mach 25(!!!) Scramjets do need air, although something to consider is that the faster you go, the more air you get. So at high altitudes with very thin air, you can go faster to get more air. In fact you have to go faster (true airspeed) in thin air anyways even if your brought along liquid oxygen for your engine, because as the air thins your stall speed will go up. The whole thing is a complicated system of equations. Engine capabilities and/or critical mach number (for planes designed for subsonic flight, like the U-2) of the airframe set an upper limit on how fast you can go. Air density decreases with altitude, increasing the stall speed (according to true airspeed, not indicated airspeed.) But for a given true airspeed, with increased altitude the temperature of the air drops, consequently dropping the speed of sound, which reduces the mach number. In subsonic planes as altitude goes up the stall speed and critical mach number eventually pass each other, beyond which your plane can no longer fly. The point of that intersection is known as the 'coffin corner'. In planes designed for supersonic flight passing the critical mach number isn't a problem, but eventually you'll reach a point where the drag on the aircraft is so great that the engines simply don't have enough power to overcome it. Increasing altitude reduces drag as the air gets thinner, but that only works for so long. Air speed inside the engines needs to be considered too. The airspeed past the turbine blades needs to be such that you won't get compressor stall. When you discard the turbine requirement, that's where things start to get interesting. A ramjet has no turbines, it compresses the air using the intake geometry. At full speed the SR-71 was actually producing most of it's thrust with a ramjet effect, most of the air going into the engines was not going through the turbines. The difference between a ramjet and a scramjet is that in a ramjet, the air inside the engine becomes subsonic again for the burn, but in a scramjet the air inside the engine remains supersonic. Scramjets could go really fast.
djyaz1200 8y ago
If you're into this kind of stuff the book Skunk Works by Ben R Rich is REALLY good! IMO it carries a lot of lessons into software development and startups also. Like they did random startup type things where for example the external starter motor for the planes engines was made from a couple Buick motors. They spent lavishly where they had to but were frugal and kept it simple where they could. Fun + interesting read.
godelmachine 8y ago
A bit unrelated , but would someone please explain how come missiles fired from Stinger MANPADS are so fast?
- ceejayoz 8y ago
  They're small, light weight, and about 80% fuel. Without a squishy human on board, rockets can accelerate very quickly.
- Armisael16 8y ago
  They really aren’t. They can only get up to ~750 m/s. You want fast, take a look at the Sprint missiles. The damn things had 100g of acceleration and could hit 3400 m/s.
  - dexen 8y ago
    Did you say Sprint missiles? https://youtu.be/xZTjA44T6tY?t=93 https://youtu.be/xZTjA44T6tY?t=93
    - Armisael16 8y ago
      I do actually follow him, but I hadn’t seen that yet.
sandworm101 8y ago
Opinion: SR-71 does not deserve its records. There are many faster objects, including the X-15 and Shuttle. Both are faster than the Blackbird but do not count. Shuttle is a spacecraft but even during reentry, shuttle could not hit such speeds unaided by other aircraft that departed from it along the way (the boosters etx). Nor could the X-15 which was dropped from a larger carrier aircraft. Both could not get to their records speed unaided. Neither could the SR-71/YF-12. They burnt so much fuel getting off the ground that, to preform a run to top speed and get home, they needed to refuel. So how is that fundamentally different than Shuttle or the X-15? For an aircraft to qualify as an aircraft it should be able to get up and down without help. Therefore it is the Mig-25/31 that deserves the praise of "fastest aircraft".
- avar 8y ago
  This is an urban legend. Landing it when it was almost empty was gentler on the landing gear, so they took off with relatively little fuel in case the mission was scrubbed. They could have taken off and accelerated to record-breaking speeds if that's all they wanted to do, but the typical mission profile was to fly to far away locations to conduct surveillance, so in-air refueling was always part of the mission profile.
  - sandworm101 8y ago
    That's not the information I've seen. From what I've read a fully-loaded takeoff and climb would burn so much fuel, far more than a typical profile, that it would still not have been able to break records set by the migs.
    - avar 8y ago
      These two claims aren't mutually exclusive.
    - jandrese 8y ago
      That sounds dubious to me. The SR-71 had some massive tanks and the idea that it couldn't accelerate to full speed on one tank seems unlikely. Even if you account for the burn in climbing to 50k feet ASL it seems like it has to be underselling the Blackbird quite a lot.
petschge 8y ago
There is a few really great stories about the SR-71 on the internet, many out of the book "Sled Driver". I would not (as it is customary on other parts of the internet) leave the full copy-pasta here, but I do recommend the "air speed check) story (to be found e.g. at https://oppositelock.kinja.com/favorite-sr-71-story-1079127041 https://oppositelock.kinja.com/favorite-sr-71-story-10791270... ) and the low fly-by (e.g. at https://foxtrotalpha.jalopnik.com/the-sr-71-blackbirds-most-spectacular-flyover-was-also-1719654907 https://foxtrotalpha.jalopnik.com/the-sr-71-blackbirds-most-...).
- JustSomeNobody 8y ago
  I re-read the "air speed check" story every time it's posted. It never gets old.
  - plainOldText 8y ago
    Same here! I first came across the story here on HN, and every time someone mentions it I re-read it. It truly never gets old; only now I just got goosebumps. I think it's the people bonding part that gets me.
123jay7 8y ago
The greatest story ever about the SR-71 https://oppositelock.kinja.com/favorite-sr-71-story-1079127041 https://oppositelock.kinja.com/favorite-sr-71-story-10791270...
adolph 8y ago
One of the authors, David Cenciotti, also has a nice aviation (primarily military) weblog [1] and made some interesting speculation about that stealth Blackhawk [2]. 1. https://theaviationist.com/ https://theaviationist.com/ 2. https://theaviationist.com/tag/stealth-black-hawk/ https://theaviationist.com/tag/stealth-black-hawk/
amriksohata 8y ago
On paper it would out run any missle with prior warning. But in reality in a dog fight at close range its unlikely it would be at top speed to do so quickly enough.
- ben7799 8y ago
  There is no such thing as "dogfight at close range" with an aircraft that travels at Mach 3+ when cruising into enemy territory. Even the slightest turn at those speeds moves the airplane by 10s of miles. Any attempt to intercept or shoot down planes that fast happens at great distances and is totally dependent on computers, radar, and missiles.
  - amriksohata 8y ago
    It wouldn't get much time to spy at that speed, it has to slow down at its destination and it's fuel limits won't allow great distances without speed changes. Top speed is different from real speed
    - ceejayoz 8y ago
      You're badly misinformed on the SR-71. > It wouldn't get much time to spy at that speed That's why you take photos and do the spying part back on base. The SR-71's weapon was its sophisticated camera setup. > it's fuel limits won't allow great distances without speed changes When it set its speed record, it crossed from LA to DC on one tank of fuel. (It tanked up immediately after takeoff and immediately before landing, but the cross-country flying part didn't involve a tanker.)
modzu 8y ago
apparently "no Blackbird of any variety has ever flown over the landmass of Russia or China", according to former SR71 pilot Col. RH Graham. so we don't really know if they have the capability, but after they downed the U2 in 1960, seems the US didn't want to find out empirically. that said, you have to love this plane. it's a spaceship.
- AnimalMuppet 8y ago
  I recall reading a story of flying an SR71 through the cloud from a Chinese nuclear test. We wanted to know if it was a fusion weapon or not. The Chinese sent up a fighter after it, and, well, it wasn't fast enough. It also had too low of a ceiling. Can't cite a source (I read about this, what, four decades ago?) so I can't prove it happened.
vermontdevil 8y ago
Y’all should really go to the National Museum of the US Air Force. You’ll see almost all of the planes mentioned here there. And it’s free. Nothing like seeing Blackbird in person as well as all the other planes. Plan on a full day at the place.
Latteland 8y ago
Remember the U2, the predecessor that was shot down famously. https://en.wikipedia.org/wiki/Francis_Gary_Powers https://en.wikipedia.org/wiki/Francis_Gary_Powers.
linsomniac 8y ago
If you haven't heard the "SR-71 Speed Check" story, it's pretty amusing. As told by the pilot: https://www.youtube.com/watch?v=8AyHH9G9et0 https://www.youtube.com/watch?v=8AyHH9G9et0
deleted 8y ago
[deleted]
rident 8y ago
There's a Lockheed A-12 on the USS Intrepid that you can get very close to with a guided tour. One of the facts the tour guides tell you about it is the titanium for the planes, as well as that of the SR-71s, was mostly sourced from Russia via shell companies for all kinds of bullshit reasons. So, America flew spy planes over Russia that were made from materials mostly of Russian origin.
libertyhouse 8y ago
I wish more SR-71 stories focused on the sensors and defensive systems. Although not a sexy as the aircraft, in some ways the SR-71 could be considered a "sensor truck." Post-mission processing and analysis of raw data was a huge part of the total SR-71 program. The system and sensor manufacturers were on the cutting edge of airborne reconnaissance and remote sensing. Good page on some of the sensors here: http://www.sr71.us/sr_sensors_pg3.htm http://www.sr71.us/sr_sensors_pg3.htm
ablekh 8y ago
Here are some relevant and IMO very interesting videos for your viewing pleasure: https://www.youtube.com/watch?v=reytu0y5efs https://www.youtube.com/watch?v=reytu0y5efs https://www.youtube.com/watch?v=-5nSKLyrM1s https://www.youtube.com/watch?v=-5nSKLyrM1s (long talk by SR-71 pilot Maury Rosenberg mentioned in the first video) https://www.youtube.com/watch?v=CeBu6mRDaro https://www.youtube.com/watch?v=CeBu6mRDaro (an even longer talk by another SR-71 pilot Richard Graham)

188 points by jrs235 8y ago

To me the most interesting part of this article is that I missed there was a contract awarded for a Mach 6 SR-72, that may or may not already have a sighted test platform.

rootbear 8y ago

A friend of mine served in the Air Force on the refueling planes that serviced the SR-71s. He said that it was hard for the refueling plane to go as fast as the SR-71's slowest speed! So they did the refueling in a shallow dive, to give the refueling plane a boost.

areoform 8y ago

Is there any single piece of technology that's more retro-futuristic than the SR-71? It is undefinably iconic especially if you understand what happened behind the scenes. Lockheed's Skunk Works managed to not only look into the future, but they managed to make it manifest in the past. The first one took flight over fifty years ago and we still talk about it as if they represent the promise of the future. As a culture and community, we rarely view Project Apollo in the same way. To me, in contrast to the Blackbird, our first step outside our cradle looks dated. The Saturn V is an ode to the sheer force of will required to send human beings to another heavenly body. It certainly looks the part. The Blackbirds, on the other hand, were precise, surgical instruments designed to cut borders and they look the part. Every element of the plane ends in that sharp-looking edge. There are no blunt surfaces on it. It’s one complex curve wrapped around itself and stretched into that timeless shape. And that's before you pull back on the curtain. I don't have online sources for this, but I have read books about the project that explained how every single part within the Blackbirds - from the engines to the paint - was brought into being for this project. They set out to do something so daring and so pioneering that they had to invent new alloys to do it. And then they had to build the machines to work that alloy: new machines - tape-based robots - to precisely carve it into shape, new procedures to put it together, and new philosophies to let it fly. These planes were designed to fly so fast that ordinary Titanium-based alloys would melt or weaken over time leading to rapid, unplanned disassembly. They didn’t have more advanced ceramics which could do the job, so Kelly Johnson’s team came up with a new alloy that was annealed - or re-tempered - in flight, so that it became stronger and stronger over time. Theoretically above some classified altitude the Blackbird can go much faster than Mach 3 and keep on going until the airframe melts away at some crazy high, theoretical speed no one has bothered to check. They did all of that in a past where the most sophisticated engineering tool in common use was a slide rule and the first scientific pocket calculator was nearly a decade into the future. Do you ever wonder when we'll build something so daring that it will finally eclipse this project? I do. Paraphrasing Thiel, "what happened to the future? We were promised Blackbirds and got the F-35 instead."

blattimwind 8y ago
> Paraphrasing Thiel, "what happened to the future? We were promised Blackbirds and got the F-35 instead." It's kinda weird how the F-35 just looks somehow dated and like a slob compared to e.g. the older (and cooler looking) F-22. Though perhaps "cool looks" is maybe not the prime factor in fighter jet selection...
- combatentropy 8y ago
  Kelly Johnson, who led the project to build the Blackbird, disagrees. "All of us had been trained by Kelly Johnson and believed fanatically in his insistence that an airplane that looked beautiful would fly the same way." --- Ben Rich, Skunk Works This quote opens an essay on beauty by Paul Graham, http://www.paulgraham.com/taste.html http://www.paulgraham.com/taste.html
  - js2 8y ago
    Function follows form?
    - ReptileMan 8y ago
      They merge at a point. The moment they merge you have achieved Nir... Unix ideal.
  - mixmastamyk 8y ago
    Believe he also had to be convinced by Rich to support the boxy F-117A.
    - Teknoman117 8y ago
      The F-117 was mostly a limitation of computing technologies at the time. We (apparently) didn't have the horsepower to model radar hitting curved surfaces, so the boxy plane came as a result of the limitations of the modelling system.
- 8y ago

SEJeff 8y ago

There is an unbelievably good interview with Brian Shul, one of the only SR-71 pilots to take a bunch of pictures of the plane[1]. He tells the story about when his commander asks him to fly right up to the soviet border to get their anti-air radars to light the blackbird up. He asked what he should do if they shot missiles at it and his commander said to just turn around and outrun it. He was quite skeptical of this and very amusingly describes this real life encounter. He's a really funny speaker. [1] https://www.youtube.com/watch?v=BZRP1q1PGUk&t=33m0s https://www.youtube.com/watch?v=BZRP1q1PGUk&t=33m0s UPDATE: Video with better sound thanks to https://news.ycombinator.com/item?id=19505767 https://news.ycombinator.com/item?id=19505767 I found the specific story I was referring to at 33m

WestCoastJustin 8y ago
+∞. I watch this anytime I need motivation. This guy is the epitome of not letting anything get in his way. Such a good public speaker and amazing career! Cannot upvote that video enough. Here's one with better sound: https://www.youtube.com/watch?v=BZRP1q1PGUk https://www.youtube.com/watch?v=BZRP1q1PGUk
- SEJeff 8y ago
  Thanks updated! (33m0s is the story I was referring to)

jclay 8y ago

The SR-71 flight manual can also be found here [0]. I was surprised to find the plane can be flown solo [1], and with no pressure suit below 50,000 feet [2]. There is also a section on "Tactical Limits" describing scenarios where exceeding normal operating limits is advised to exit a hostile area [3] 0. https://www.sr-71.org/blackbird/manual/ https://www.sr-71.org/blackbird/manual/ 1. https://www.sr-71.org/blackbird/manual/5/5-23.php https://www.sr-71.org/blackbird/manual/5/5-23.php 2. https://www.sr-71.org/blackbird/manual/5/5-23.php https://www.sr-71.org/blackbird/manual/5/5-23.php 3. https://www.sr-71.org/blackbird/manual/3/3-135.php https://www.sr-71.org/blackbird/manual/3/3-135.php

darkpuma 8y ago
> I was surprised to find the plane can be flown solo [1], Doubtlessly a consequence of the A-12 being flown solo. The SR-71 was a derivative of the A-12.
CompelTechnic 8y ago
Link [3] is hilarious in how banal it is- the same of the manual describes both how to defog your windows and how to GTFO if under hostile missile fire.

UI_at_80x24 8y ago

My favorite story about the Blackbird is how it was designed with heat and expansion in mind. On the ground to leaked fuel like a sieve[1][2], it was only once it reached operational speed that the joints & frame heated up and sealed it, (thus requiring a refueling shortly after take-off). [1] https://www.sr-71.org/blackbird/sr-71/ https://www.sr-71.org/blackbird/sr-71/ [2] http://physicsbuzz.physicscentral.com/2011/02/betrayed-by-heat-sr-71-blackbird.html http://physicsbuzz.physicscentral.com/2011/02/betrayed-by-he...

rootbear 8y ago
The ground crews, I'm told, hated this plane because it leaked toxic fuel everywhere while on the ground and was otherwise a pain to deal with. These sorts of stories are what impress me about programs like this. No commercial product could ever be so expensive, so difficult, so wildly impractical. The military are practically the only ones who can do things like this, because the need is so great it justifies all the craziness. I work at NASA and we do crazy things like sending robots to Mars, but that seems tame compared to the insanity of something like the SR-71.
Teknoman117 8y ago
The other major reasons they didn't load much fuel on the ground is that the engine fuel economy at low speeds and low altitudes was atrocious. After refueling, the crews would head for the cruising altitude as soon as possible.

deepnotderp 8y ago

I don't know the full veracity of this piece, but IIRC the Foxbat once acquired a lock on it: https://theaviationist.com/2013/12/11/sr-71-vs-mig-31/ https://theaviationist.com/2013/12/11/sr-71-vs-mig-31/

ceejayoz 8y ago
Plenty of things acquired a lock on it, including ground-based SAM sites. That's the easy part.
- adolph 8y ago
  The USSR pilot claims: “Had the spy plane violated Soviet airspace, a live missile launch would have been carried out. There was no practically chance the aircraft could avoid an R-33 missile.”
  - ceejayoz 8y ago
    The pilot also claims the lock was from 120km, which is the maximum range of the R-33 at the time, so I'm a bit dubious of the idea without a practical demonstration. I do suspect the "surround from all directions" approach detailed later would've worked, but that's why we moved off to stealth and satellites.
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combatentropy 8y ago

I think there is a lesson here that applies to more than just planes. Speed often can solve a problem in a simple way. The enemy will fire missiles at us. What shall we do? (1) Invent missile-proof armor, (2) Build computer-guided anti-missile lasers, (3) Just fly really fast. I guess all of those are hard to do. Making the SR-71 fly at Mach 3 wasn't easy. But to me it seems more elegant. In the early 2000s, Google made a big deal about speed in web apps. I think it still does, but I don't hear about it anymore. And everybody knows that GMail is slower. But I appreciated it while it lasted.

guhidalg 8y ago
This resonates with how I like to solve problems. Instead of thinking about how we can fix it or mitigate it, how can we make it impossible for a certain kind of problem to occur? Maybe it's just my procrastination speaking but I find it easier to just wipe out entire kinds of issues.

andy_adams 8y ago

I don't know much about aviation, but I know there's a plane that was faster than the SR-71: The X-15 [1]. I know because my great uncle died flying the X-15 on an experimental flight [2], so it's always been an interesting story for my family. [1] https://en.wikipedia.org/wiki/North_American_X-15 https://en.wikipedia.org/wiki/North_American_X-15 [2] https://theaviationgeekclub.com/the-story-of-mike-adams-the-only-pilot-to-lose-his-life-during-the-x-15-flight-test-program/ https://theaviationgeekclub.com/the-story-of-mike-adams-the-...

mr_overalls 8y ago
I find it absolutely incredible that the piloted speed record set by this aircraft - set in October 1967 when William J. Knight flew Mach 6.7 - hasn't been broken in 50+ years.
- rtkwe 8y ago
  It's a mix of things I think. First we haven't had a really big breakthrough in engine technology in a while and second there's no need to risk a person piloting these anymore because computers and remote control tech has gotten good enough.
  - ProAm 8y ago
    Wouldnt the scramjet engines be a pretty big breakthrough?
    - dmoy 8y ago
      Scramjet still needs air though, doesn't it? Thus it has to fly lower, and maybe can't get as fast as a rocket engine. Scramjet planes are faster than other non-rocket planes I would imagine?
      - darkpuma 8y ago
        The SR-71 cruised at Mach 3.2. Scramjets have been demonstrated to do Mach >5, and theoretically might be capable of something between Mach 17 to Mach 25(!!!) Scramjets do need air, although something to consider is that the faster you go, the more air you get. So at high altitudes with very thin air, you can go faster to get more air. In fact you have to go faster (true airspeed) in thin air anyways even if your brought along liquid oxygen for your engine, because as the air thins your stall speed will go up. The whole thing is a complicated system of equations. Engine capabilities and/or critical mach number (for planes designed for subsonic flight, like the U-2) of the airframe set an upper limit on how fast you can go. Air density decreases with altitude, increasing the stall speed (according to true airspeed, not indicated airspeed.) But for a given true airspeed, with increased altitude the temperature of the air drops, consequently dropping the speed of sound, which reduces the mach number. In subsonic planes as altitude goes up the stall speed and critical mach number eventually pass each other, beyond which your plane can no longer fly. The point of that intersection is known as the 'coffin corner'. In planes designed for supersonic flight passing the critical mach number isn't a problem, but eventually you'll reach a point where the drag on the aircraft is so great that the engines simply don't have enough power to overcome it. Increasing altitude reduces drag as the air gets thinner, but that only works for so long. Air speed inside the engines needs to be considered too. The airspeed past the turbine blades needs to be such that you won't get compressor stall. When you discard the turbine requirement, that's where things start to get interesting. A ramjet has no turbines, it compresses the air using the intake geometry. At full speed the SR-71 was actually producing most of it's thrust with a ramjet effect, most of the air going into the engines was not going through the turbines. The difference between a ramjet and a scramjet is that in a ramjet, the air inside the engine becomes subsonic again for the burn, but in a scramjet the air inside the engine remains supersonic. Scramjets could go really fast.

djyaz1200 8y ago

If you're into this kind of stuff the book Skunk Works by Ben R Rich is REALLY good! IMO it carries a lot of lessons into software development and startups also. Like they did random startup type things where for example the external starter motor for the planes engines was made from a couple Buick motors. They spent lavishly where they had to but were frugal and kept it simple where they could. Fun + interesting read.

godelmachine 8y ago

A bit unrelated , but would someone please explain how come missiles fired from Stinger MANPADS are so fast?

ceejayoz 8y ago
They're small, light weight, and about 80% fuel. Without a squishy human on board, rockets can accelerate very quickly.
Armisael16 8y ago
They really aren’t. They can only get up to ~750 m/s. You want fast, take a look at the Sprint missiles. The damn things had 100g of acceleration and could hit 3400 m/s.
- dexen 8y ago
  Did you say Sprint missiles? https://youtu.be/xZTjA44T6tY?t=93 https://youtu.be/xZTjA44T6tY?t=93
  - Armisael16 8y ago
    I do actually follow him, but I hadn’t seen that yet.

sandworm101 8y ago

Opinion: SR-71 does not deserve its records. There are many faster objects, including the X-15 and Shuttle. Both are faster than the Blackbird but do not count. Shuttle is a spacecraft but even during reentry, shuttle could not hit such speeds unaided by other aircraft that departed from it along the way (the boosters etx). Nor could the X-15 which was dropped from a larger carrier aircraft. Both could not get to their records speed unaided. Neither could the SR-71/YF-12. They burnt so much fuel getting off the ground that, to preform a run to top speed and get home, they needed to refuel. So how is that fundamentally different than Shuttle or the X-15? For an aircraft to qualify as an aircraft it should be able to get up and down without help. Therefore it is the Mig-25/31 that deserves the praise of "fastest aircraft".

avar 8y ago
This is an urban legend. Landing it when it was almost empty was gentler on the landing gear, so they took off with relatively little fuel in case the mission was scrubbed. They could have taken off and accelerated to record-breaking speeds if that's all they wanted to do, but the typical mission profile was to fly to far away locations to conduct surveillance, so in-air refueling was always part of the mission profile.
- sandworm101 8y ago
  That's not the information I've seen. From what I've read a fully-loaded takeoff and climb would burn so much fuel, far more than a typical profile, that it would still not have been able to break records set by the migs.
  - avar 8y ago
    These two claims aren't mutually exclusive.
  - jandrese 8y ago
    That sounds dubious to me. The SR-71 had some massive tanks and the idea that it couldn't accelerate to full speed on one tank seems unlikely. Even if you account for the burn in climbing to 50k feet ASL it seems like it has to be underselling the Blackbird quite a lot.

petschge 8y ago

There is a few really great stories about the SR-71 on the internet, many out of the book "Sled Driver". I would not (as it is customary on other parts of the internet) leave the full copy-pasta here, but I do recommend the "air speed check) story (to be found e.g. at https://oppositelock.kinja.com/favorite-sr-71-story-1079127041 https://oppositelock.kinja.com/favorite-sr-71-story-10791270... ) and the low fly-by (e.g. at https://foxtrotalpha.jalopnik.com/the-sr-71-blackbirds-most-spectacular-flyover-was-also-1719654907 https://foxtrotalpha.jalopnik.com/the-sr-71-blackbirds-most-...).

JustSomeNobody 8y ago
I re-read the "air speed check" story every time it's posted. It never gets old.
- plainOldText 8y ago
  Same here! I first came across the story here on HN, and every time someone mentions it I re-read it. It truly never gets old; only now I just got goosebumps. I think it's the people bonding part that gets me.

123jay7 8y ago

The greatest story ever about the SR-71 https://oppositelock.kinja.com/favorite-sr-71-story-1079127041 https://oppositelock.kinja.com/favorite-sr-71-story-10791270...

adolph 8y ago

One of the authors, David Cenciotti, also has a nice aviation (primarily military) weblog [1] and made some interesting speculation about that stealth Blackhawk [2]. 1. https://theaviationist.com/ https://theaviationist.com/ 2. https://theaviationist.com/tag/stealth-black-hawk/ https://theaviationist.com/tag/stealth-black-hawk/

amriksohata 8y ago

On paper it would out run any missle with prior warning. But in reality in a dog fight at close range its unlikely it would be at top speed to do so quickly enough.

ben7799 8y ago
There is no such thing as "dogfight at close range" with an aircraft that travels at Mach 3+ when cruising into enemy territory. Even the slightest turn at those speeds moves the airplane by 10s of miles. Any attempt to intercept or shoot down planes that fast happens at great distances and is totally dependent on computers, radar, and missiles.
- amriksohata 8y ago
  It wouldn't get much time to spy at that speed, it has to slow down at its destination and it's fuel limits won't allow great distances without speed changes. Top speed is different from real speed
  - ceejayoz 8y ago
    You're badly misinformed on the SR-71. > It wouldn't get much time to spy at that speed That's why you take photos and do the spying part back on base. The SR-71's weapon was its sophisticated camera setup. > it's fuel limits won't allow great distances without speed changes When it set its speed record, it crossed from LA to DC on one tank of fuel. (It tanked up immediately after takeoff and immediately before landing, but the cross-country flying part didn't involve a tanker.)

modzu 8y ago

apparently "no Blackbird of any variety has ever flown over the landmass of Russia or China", according to former SR71 pilot Col. RH Graham. so we don't really know if they have the capability, but after they downed the U2 in 1960, seems the US didn't want to find out empirically. that said, you have to love this plane. it's a spaceship.

AnimalMuppet 8y ago
I recall reading a story of flying an SR71 through the cloud from a Chinese nuclear test. We wanted to know if it was a fusion weapon or not. The Chinese sent up a fighter after it, and, well, it wasn't fast enough. It also had too low of a ceiling. Can't cite a source (I read about this, what, four decades ago?) so I can't prove it happened.

vermontdevil 8y ago

Y’all should really go to the National Museum of the US Air Force. You’ll see almost all of the planes mentioned here there. And it’s free. Nothing like seeing Blackbird in person as well as all the other planes. Plan on a full day at the place.

Latteland 8y ago

Remember the U2, the predecessor that was shot down famously. https://en.wikipedia.org/wiki/Francis_Gary_Powers https://en.wikipedia.org/wiki/Francis_Gary_Powers.

linsomniac 8y ago

If you haven't heard the "SR-71 Speed Check" story, it's pretty amusing. As told by the pilot: https://www.youtube.com/watch?v=8AyHH9G9et0 https://www.youtube.com/watch?v=8AyHH9G9et0

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rident 8y ago

There's a Lockheed A-12 on the USS Intrepid that you can get very close to with a guided tour. One of the facts the tour guides tell you about it is the titanium for the planes, as well as that of the SR-71s, was mostly sourced from Russia via shell companies for all kinds of bullshit reasons. So, America flew spy planes over Russia that were made from materials mostly of Russian origin.

libertyhouse 8y ago

I wish more SR-71 stories focused on the sensors and defensive systems. Although not a sexy as the aircraft, in some ways the SR-71 could be considered a "sensor truck." Post-mission processing and analysis of raw data was a huge part of the total SR-71 program. The system and sensor manufacturers were on the cutting edge of airborne reconnaissance and remote sensing. Good page on some of the sensors here: http://www.sr71.us/sr_sensors_pg3.htm http://www.sr71.us/sr_sensors_pg3.htm

ablekh 8y ago

Here are some relevant and IMO very interesting videos for your viewing pleasure: https://www.youtube.com/watch?v=reytu0y5efs https://www.youtube.com/watch?v=reytu0y5efs https://www.youtube.com/watch?v=-5nSKLyrM1s https://www.youtube.com/watch?v=-5nSKLyrM1s (long talk by SR-71 pilot Maury Rosenberg mentioned in the first video) https://www.youtube.com/watch?v=CeBu6mRDaro https://www.youtube.com/watch?v=CeBu6mRDaro (an even longer talk by another SR-71 pilot Richard Graham)