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I’d recommend reading Skunk Works by Ben R. Rich for more on the engineering of the Blackbird and other special aviation projects. I knew the Blackbird was fas
by austinl 3y ago
I’d recommend reading Skunk Works by Ben R. Rich for more on the engineering of the Blackbird and other special aviation projects.
I knew the Blackbird was fast, but didn’t quite realize how fast until reading this book. The SR-72 would cruise at Mach 3, or three times the speed of sound. It would do this at 80,000 feet, over twice the traditional cruising altitude of a 747. Even at this height, where the temperature is -60°F, friction would cause the fuselage to heat to 600°F. This would melt traditional aircraft, so the plane was built with titanium (ironically supplied by the Soviet Union). The Blackbird used to overfly North Korea five days a week in just ten minutes.
- nehal3m 3y agoAccording to this [0] article it leaks fuel sitting on the runway because: "The fuel system of the SR-71 could not be sealed permanently because there simply were no sealants that were flexible and durable enough to deal with those kind of temperatures and shrinking-expansion cycles." I think that says enough about how bonkers fast that thing is. [0] https://nodum.org/was-sr-71-blackbird-leaking-fuel/ https://nodum.org/was-sr-71-blackbird-leaking-fuel/
- SkyMarshal 3y agoYeah, heat expansion made it airtight at Mach 3, but sitting on a runway with its parts contracted back to normal dimensions, it had leaks.
- GartzenDeHaes 3y agoNot just on the runway. The hangers had big drains in them to catch the fuel and anyone unfortunate enough to have to work under the plane would get soaked. "Hey, I think the plane is leaking" -- me.
- SkyMarshal 3y ago/second that book, one of the best on US aviation history and engineering. Also iirc, ironically the technique for shaping the F-117 to reflect away radar came from a Soviet journal article on shaping nosecones to minimize their interference on radar emanating from them.
- p_l 3y agoAnother fun thing is that claims about no computers being used for A-12/SR-71 are mostly boasting possibly to avoid mentioning then black project details, like CIA buying a custom computer (PDP-2) to do calculations on A-12 shape.
- Loughla 3y agoWhat blows my mind is that this aircraft was originally shown, formally, in 1964. 1.9.6.4. They had this level of engineering in 1964. Just imagine what shit goes on behind closed doors today. It really does sort of stagger you.
- game_the0ry 3y agoGiven how bloated and wasteful our government is today, and how much the dept of defense blew on the F-35, I would be staggered if anything useful happens behind closed doors, besides corruption. I think we were able to accomplish a lot more in the past.
- Mistletoe 3y agoPowerpoint was created in 1987 and it was all downhill from there according to the military. https://www.theatlantic.com/politics/archive/2010/04/why-the-military-declared-war-on-powerpoint/345802/ https://www.theatlantic.com/politics/archive/2010/04/why-the...
- marcus_holmes 3y agoThanks for the link, that's fascinating, and resonates so much. Do you know what they used instead?
- katbyte 3y agoIndeed https://m.youtube.com/watch?v=aZ-7U95LYTo https://m.youtube.com/watch?v=aZ-7U95LYTo
- Psyladine 3y agoNot just for military: https://mcdreeamiemusings.com/blog/2019/4/13/gsux1h6bnt8lqjd7w2t2mtvfg81uhx https://mcdreeamiemusings.com/blog/2019/4/13/gsux1h6bnt8lqjd... Turns out trying to contain a complex system within a simple system of abstractions is a trendline towards disaster for any enterprise.
- bragr 3y ago
- carabiner 3y agoI've got a lil titanium bowl for camping. Feels like alien material, it's so light and feels like you could snap it, but then it's incredibly strong. I used it in the oven last night to make TikTok feta pasta. No worries on being oven safe as its melting temp is 3,000°F.
- jacquesm 3y agoTry working it with regular tools and you'll be even more amazed. It's incredible stuff.
- peteradio 3y agoI'm not sure how to take this comment. Is it unworkable or surprisingly workable?
- VBprogrammer 3y agoIt's quite well known for being difficult to machine generally.
- nickff 3y agoTitanium is very hard to work with; for instance the carbide coatings on many drill-bits can cause it to degrade over time. Tooling for production of the blackbirds was a challenge in and of itself, as little was known about working with titanium at the time.
- jasonwatkinspdx 3y agoThe more you cut titanium the harder it gets. It can eat even carbide drill / mill tools. Welding it is a nightmare.
- jacquesm 3y agoVery much unworkable. I got a chunk of titanium tubing at some point of my more metal oriented years and tried to do something useful with it, it ate up my tools pretty quickly. Typical standing time for a regular HSS bit was < 1 hole. Carbide did a bit better, but still that too went much faster than usual.
- vegasbrianc 3y agoCan also recommend this book. Good read.