SR-71 In-Flight Breakup
barthworks.com
barthworks.com
Must be something about this story, or perhaps the SR-71, that grabs our attention.
The SR-71 is a fantastic setting for any story, but I think what grabs me most about the story is the rationality of it. He wakes up in a strange situation, starts deducing where he is, what his situation is, how his safety systems are functioning, etc, and lands safely; then, a thorough investigation replicates the accident, finds all the root causes of the breakup, and addresses them one by one.
It's no more surprising that the story is catnip for HN than, say, the comic "Fleep" is http://www.aaronsw.com/2002/fleep/
http://jalopnik.com/5951233/this-is-the-man-who-made-the-fir...
tl;dr - the plane disintegrated around him before he had the chance to eject, and he floated to the ground thanks to his parachute. Copilot, not so lucky.
As for the article: it's a pity. The US could fly to the moon with less computer power than a dumbphone, put people in things like the SR71 (how did they actually put enough processing power for all the flight computers in a plane back then?!)... and now?
Space Shuttle's been retired, no near-time replacement. No SR71 (or anything that can be seen as a replacement), and stupid Republican teabaggers caring more about their pockets instead of the population. Seriously, America what's wrong with you?
We Germans needed the Marshall plan after WW2, maybe it's needed the other way round this time...
The Colosseum in Rome still exists because the only way to do it was to do it in stone and stone lasts forever. Since then we've built millions of arenas that won't last as long because we've used economic forces to develop just-good-enough structure. Likewise, the SR-71 has been replaced by the just-good-enough surveillance satellite.
There's another aspect too. Sometimes we do things just to see that we can. Going to the moon is in that category. If there was a compelling reason to go back we would've. The Concorde, one could argue, was in the same category - we had to have the thrill of taking commercial flight into the supersonic realm, but we found that they economics were such that the thrill of going supersonic and getting there a few hours earlier were not enough to support a market.
The original design brief was that it should be a stealth U2, but as the A-12/SR-71 project developed it became clear that that wasn't possible with the technology of the time, but that they could make a platform that flew so fast the SAMs wouldn't have time to lock, launch, and intercept.
There were suborbital spy satellites available before the A-12 even flew: http://en.wikipedia.org/wiki/Corona_%28satellite%29
The problem was that the cost of the keyhole program was incredible, you needed a whole launch platform plus a whole recovery mission every time you wanted to take a picture. So the SR-71 was a cost-saving measure versus Keyhole.
Currently the us military can get the information that the SR-71 could provide more easily and with less danger and cost.
Given that the primary motivation for the SR-71 (and, before it, the A-12) was to have a platform wasn't vulnerable to interception like the U-2, I think satellites aren't merely "just good enough", they are far better in that key respect.
They might be worse at "be where we want on demand", but if that's the overriding concern, there's all kinds of other platforms (drones, U-2). The problem with the SR-71 is that it is highly optimized for survivability through speed, but the speed it has doesn't do enough for survivability to be worth the cost given the other alternatives available.
> There's another aspect too. Sometimes we do things just to see that we can. Going to the moon is in the category.
Well, if you ignore the Cold War geopolitical context of the space race, sure, going to the moon was "just to see that we can".
The Colosseum (and much Roman construction) was built with stone but also concrete. The composition of Roman concrete is such that it's much more durable than most modern concrete, due in part to material properties not well understood until recently.
There's also a survivor bias built into structures which have survived the test of time: by definition, what's lasted are the structures which have lasted.
I'm often extremely critical of off-topic political content, but think that "unusual" content that highlights some interesting bit of the world is great! It definitely fits "intellectually gratifying" far more than politics, or the latest "outrage story".
I'm happy to read well-written articles about things that are new and interesting to me.
I'm not sure about the SR-71 but not all "computers" (or better, control devices) were digital.
PID controllers are "trivial" in analog electronics (which were already small at that time) as well as other types of controllers.
Several studies on chaotic movement comes from this time, as well as things like this: http://en.wikipedia.org/wiki/Lyapunov_stability
Agreed. A couple of op-amps / capacitors / resistors and there you go.
You also have to remember that many of the cycles on a modern desktop are wasted, dealing with the gui, and lots of abstraction layers. Most embedded control systems are much simpler, and are closer to the baremetal, so they don't need GHz of computing power.
The SR-72 would be a pretty impressive effort, if realised.
http://www.lockheedmartin.com/us/news/features/2013/sr-72.ht...
That explains where (alot of) the money went.
That and all that NSA crap.
Nothing wrong with day-dreaming. Many of us aspire to be like Elon Musk or Richard Branson, and they certainly spent their fair share dreaming about what's possible with the latest technologies.
It's also interesting to get different groups of peoples perspective on different subjects. If you posted this question on multiple sites dedicated to a subset of the population (developers, entrepreneurs, moms, croquet enthusiasts, stock-car racing enthusiasts, sales-people, 5th graders) it would be interesting to see the different responses, and to see how much group-think there would be depending on how the first few comments sounded.
Some news topics are inappropriate for HN in my opinion. The current news topic about the missing airplane doesn't really need to be here unless there are people whose only source of news is HN.
In the mid-70s an SR-71 was deployed to the UK and of course it was a sensation in that part of the world. Uncharacteristically, I bullied my mother into collecting breakfast cereal box coupons so I could get a snap-together plastic model of the plane.
Also, it's much more of a hacker's plane than the 'waterfall' approach of things like the F-35. The fact that you start the engines by setting off a small explosion on a special truck surely appeals to a lot of people here.
Incidentally, I find this sidebar extremely distracting; maybe it's time for a plugin/script to fix it.
What's not to like?
One thing I wonder about after reading this is why, if they were able to recreate the entire flight profile in a simulator the next day and see the same result, would they not just test everything in the simulator first?
For the post-accident simulation, they say "ok since we know we are in this modification of the SR-71, in this phase of the flight, and this accident happens, and this backup fails... ok yeah it looks like that's pretty bad.
However, "the right engine inlet's automatic control system malfunctioned".
That probably wasn't part of their simulation. While it sounds like they could have erred on the side of caution and cancelled the remaining tests after that occurred, they must have been confident in their manual control abilities.
Even if they had simulated with the inlet(s) under manual control, real life airflow and reaction times are going to vary.
I wouldn't have guessed the Blackbird has better handling than the modern Ford GT40.
"[E]xtracting myself from the parachute harness, I discovered the source of those flapping-strap noises heard on the way down. My seat belt and shoulder harness were still draped around me, attached and latched."
in the blockbuster film adaptation of this account, (starring Keanu Reeves) the pilot is still holding the stick when his parachute brings him to the ground.