The SR-71 was the most extraordinary aircraft ever flown, and it first flew in 1964, only 19 years after WW 2.

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Lugwho · 61-69, M

There's one at the Duxford air museum, near to where I used to live. The information board says it was designed to leak fuel, but a quick google suggests this might be a myth. I have no idea, but I quite like the idea of the experts being taken in by a myth.

Bumbles · 51-55, M

@Lugwho Yes, the SR-71 Blackbird did leak fuel, but not by original design intent. The leaks were a result of engineering trade-offs and the limitations of available materials, not a deliberate feature.

We have one here in LA. Amazing to see the lines of it.

Lugwho · 61-69, M

@Bumbles That might be what the info board said. It's a long time since I was there.

SomeMichGuy · M

@Lugwho The leaking was only while on the ground.

At speed, the Ti would expand and the leaks would stop.

And remember, this air-/spacecraft was designed using slide rules.

SomeMichGuy · M

@Bumbles @Lugwho

Lockheed actually had a lot of problems working with Ti. Some issues are recorded here

https://wisconsinmetaltech.com/titanium-and-the-sr-71/

https://www.lockheedmartin.com/en-us/news/features/history/blackbird.html

Something I remember reading about years ago is referred to in the first reference:

They discovered that their cadmium plated tools were leaving trace amounts of cadmium on bolts, which would cause galvanic corrosion and cause the bolts to fail. This discovery led to all cadmium tools to be removed from the workshop.

I remember reading that the bolts would actually fall out! As a result of this issue, they made tools out of Ti in order to work on the Ti plane.