Interesting Stuff, Wisdom from an airplane mechanic Options

[bigkensteele]

A buddy of mine who has his own plane sent this link to me knowing I would find it interesting due to the great similarities between air-cooled aviation engines and the ones in our cars.

It is long, but very informative. Touches on burnt valves, cylinder/case cracks, etc.

Teaser - the first 15 minutes or so explains why compression tests are close to worthless.


https://www.youtube.com/watch?v=4NnOYvOlMB8

[gereed75]

Being a pilot (fixed wing and helo) and an operator and builder of air cooled plane engines, I would say there are many parallels between these two motors. The biggest thing in aero engines is you have a manufacturer that tells you how to operate and there is a lot of CYA written into the equation. And remember, the pilot has a mixture control in the cockpit. Add that to a generally poor understanding (and sometimes fear) on the case of most pilots, and the potential for much engine abuse exists. Then throw in a government regulatory body and you can imagine the BS that ensues.

Savvy pilots use EGT as the means of correctly setting mixture (actually AFR) for various operating regimes. The physics/thermodynamics that occur from there are identical in either engine

BTW, in an autorotation the glide may suck, but you do have the ability to land with zero airspeed and zero sink rate. That has some distinct advantages to gliding in at flying speed in a fixed wing

[somd914]

BTW, in an autorotation the glide may suck, but you do have the ability to land with zero airspeed and zero sink rate. That has some distinct advantages to gliding in at flying speed in a fixed wing

Agree, but auto gyration is no guarantee of a safe landing, and outside of the military, I don't think it is well trained and refreshed on a regular basis. Nor is gliding into unimproved surface at 120+ knots in a commercial passenger jet a guarantee of a safe landing.

But that is neither here nor there, back to the matter at hand. My brother is an A&P of almost 35 years, still turning wrenches. His take on leak down tests (compression in their case), it is a useful tool but not a perfect tool. Everybody is entitled to their opinions.

Also agree that between manufacturer liability and government legislation for safety, maintenance requirements are likely stricter than need be. On the other hand, based on the junk I see on our roads, I sometimes wish we had more regulation on cars in regard to maintenance before one of them smacks me due to mechanical failure.