Welcome to Episode #69 of The Thermal.

In this Episode of The Thermal, the Piper Pawnee has issues. Wing spar issues to be exact…we get an update from the Soaring Society of America's Ken Sorensen.

Electric Gliders and engine failure. Do you lock the prop or let it spin? The manual says one thing but real-world data says another. We talk to a glider pilot boffin who used his own glider as a test bed.

And a new book called Why We Fly is a wonderful journey into our relationship with flying. We speak to author Caroline Paul about her lifelong obsession with flight.

That's all on Episode #69 of The Thermal.