Sunday, December 10, 2017

Back in the Air

KFAM 101956Z AUTO 27008G15KT 10SM CLR 13/M04 A3001

at times, it seems as though this has been The Year of Not Flying. After the time down to fix the cowling, I had about two months to fly until the annual was due.

And it was not good. One of the first things that was done is a compression check. It's far more involved then this, but basically, they take a spark plug out of a cylinder, hook up a pneumatic test rig, and see how much air pressure the cylinder will hold. The reference pressure is 80psi. Compressions in the 70s are fine. 60psi is acceptable.

Last year, five out of six were in the 70s, on in the 60s. That indicates that a cylinder bears watching.

This year, five were in the 70s and one in the teens. Oopsie. The exhaust valve seat was kind of cruddy. So the cylinder was pulled off (aircraft engine cylinders are bolted to the crankcase) and sent off. Turnaround time wasn't exactly rapid. There were issues with the pushrod tube seals and other fiddly bits.

The airplane was returned to me two days ago. Yesterday was very windy and cold. Today was no peachy day, but I flew. I climbed up to 5,500' and 6,500' and flew around at full throttle to help break in the new(ish) cylinder. Landing, well, that's a 70 degree crossswind, but when you can land on grass, you've got a little more margin.

I'll probably make another hard/hot break-in flight again. Possibly in conjunction with a $100 breakfast.

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