RE: Cermark F-16 First Flight
Tom,
just of info, if you add a Jett-stream muffler on the OS108, it will help performance a good deal, but its not going to drive the rpm up all that much. You will still want to prop the engine to run in the 11.5K - 12.5 K rpm range.
As for grass ops, lots of folks flying the F-16 on grass. At least 6 I know of, 2 of those with OS91 power. From all reports, no real issues - about 150-200 feet of take-off roll
Photo here is a Jett90LX powered one, with 11x8 prop.