JP-7

I'm sure there are a lot of differences that I'm not even aware of, but typically you're dealing with flashpoints with the fuel when it comes to it.

The Blackbird required even more specialized fuel, JP-7, and while some one-offs of that have been produced, and I'm sure we could produce it again, it had some special characteristics in order to enable the Blackbird to operate.

Now, clearly a lot of science and math is occurring when you got a plane going Mach three point two.

The JP-7, it needed to have a high enough flashpoint in order to avoid unintended combustion, partly because the fuel was used as a primary heat sink to dissipate the high temperature in the airframe.

Which does make sense.

Utilize what you have on the plane in order to cool it, so has a little less of a signature.

Now, the Blackbird's Pratt & Whitney J58 engines required an intense hot flash of triethylborane in order to fire the motors, and it carried 16 shots of that.

So I guess you got 16 engine starts out of that reservoir.

The titanium panels were machined with tolerances that allowed thermal expansion when the airframe reached operating temperature.

Until then, JP-7, a specially formulated fuel with a flashpoint well above standard jet fuel, dripped on the ramp.

The procedure was to take off, rendezvous with a tanker almost immediately after departure, top off the tanks while the aircraft warmed up and sealed itself, and then accelerate to cruise.

Think about that for a moment as a pilot.

The J-58 engines are not on any current maintenance program.

Pratt & Whitney wound down support for them decades ago.

The TEB ignition compounds, the specialized JP-7 fuel, the pressure suits, the tanker coordination requirements, all of it represents a supply chain that essentially closed at the end of the last century.

The pilots and reconnaissance systems officers who flew these aircraft are in their 60s and 70s now.

You know, I've heard fun stories in the past about how at the end of the SR-71 flight program, they held a party and had an SR-71 on the ground, burned the remaining fuel, a full afterburner as part of the entertainment, which I hope is true.

Although it's unfortunate if we don't have any more JP-7, but I heard they did the same thing with the X-51 when that program ended.

They took one of the remaining aircraft and just burned all the fuel with it as part of just to have fun.

But that suggests that you can still... produce JP seven since there was some available for the X 51 program, uh, uh, 10 to 13 years after the SR 71 was retired, uh, finally.