Brief Description: Aero Sport Power IO-390 Test Run - Part 1
I received the Lycoming IO-390 test run photos from Aero Sport Power yesterday. They detail the test stand setup and connection to the various gauges for the break-in. All toll, there is about 11.5 hours of runtime across the Initial run and Extended run sheets. The first 10 hours or so are the most critical and require the most care and generally should be at full, or near-full power. This is usually pretty hard to do on a new airplane when there is a fair amount of ground and taxi tests that aren't at anywhere near full power. Having 11.5 hours of test stand run should assure proper break in and allow for a much more relaxed aircraft test phase. The extra 10 hours of run time cost about $1000 which frankly barely pays for the gas (10 hours x 19.8 GPH * $5 Gallon = $990) so it seems like a pretty good investment to assure a properly broken in engine.
The test run sheets are pretty interesting. On the first sheet, you'll note that under "full power", which I assume is slightly over 2800 RPM, they were reading 28.5" inches of manifold pressure! They were routinely measuring 28" at 2800 RPM. Sweet!
