Does anyone do an "automotive" type compression test on their aircraft
engine?

This used to be more common than the differential compression test. I have
seen a set up for a 9 cylinder radial engine that had 9 adapters and gauges so
that you can do all 9 cylinders at one time. I believe the gauges would hold
the highest reading until reset.

The old version of the AC 43.13 Acceptable Methods, Practices and Techniques,
used to mention the direct compression test as acceptable. I believe that the
current AC 43.13-1B no longer mentions it. Which begs the question is the
direct compression test no longer acceptable?

John Dupre'