That is my favorite plane. Not many people know that Skunkworks had to build them 'loose'.
So loose in fact that they leaked fluid from almost every crack and crevice sitting on the ground. It was only up at altitude and speed that its 'skin' shrunk sealing it and making it 'liquidtight'.
This is why they always took off with an absolute minimum of fuel and refueled at altitude.
Most definitely 40yrs ahead of its time and still the
fastest plane ever to fly the sky ...