Aut cum scuto aut in scuto
But worth the price.
i recall reading that the fuel efficiency actually improved the higher and faster it flew.
Yep, less drag the higher you go.
I only recently learned that this was the reason the Air Force killed it. Every single time it flew it cost $2 million and it came out of the Air Force's operating budget.
Any time JP-7 was spilled on the tarmac, it would erode the concrete.
was told that on Guam, the new guys were told to park up against the runway. when SR71 took off, all the paint would be burned off their cars