[nehal3m]

According 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/

[SkyMarshal]

Yeah, 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]

Not 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.