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Comment by malmsteen | Hacker News Reader

Stupid question: what about flying above the hurricane on the way back ? Possible ?

This is exactly what you'd do in a Concorde, U-2, SR-71, F-15, or F-22. All of these can get to the required FL600, at 60000 feet.

The F-15 and F-22 have an extra bonus. They can climb straight up through the eye. The U-2 could probably manage a spiral climb within the eye.

Depends how tall the storm is. Planes engines breathe air, and there is less air the higher you go, so there's a limit to how high you can go; roughly 10km for commerical jets (actually it's a factor of altitude and speed; at high altitude, you need to go at least a certain speed to get enough air into the engines, but if you go too fast the plane breaks apart). I think big storms are about 10km tall.

It's actually less about the engines and more about the wings. As altitude increases, the air becomes thinner. That means that wings stall speed increases. At the same time, as the air becomes thinner, the speed of sound decreases - and breaking the sound barrier will break your plane. As you go higher, the stall speed and the speed of sound converge.

The point where they meet is called "coffin corner". It is really not a nice place to be: If you are in coffin corner, if you try to descend, you risk speeding up and breaking the plane. If you try to slow down, you risk stalling - although it is possible to recover from a stall, you cannot recover without speeding up.

It is generally advisable stop climbing before you box yourself in like that.

What would a pilot do in a situation like that?

Descend very gently.

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