When we last few the single-seat Merlin PSA, it featured a two-stroke Rotax engine and we enjoyed the heck out of it. It's a nimble - yet solid - airplane that is easy to put down wherever you was it, and is fun to throw around the sky. That was two years ago - and Chip Erwin, importer of the Merlin kit, has not stood still. Aside from working on various electric airplane options and flirting with floats for the Merlin, he has continued to look for a four-stroke engine that matched the Merlin's performance envelope - and he found it in the 60-horsepower HKS 700E.
We got a chance to fly the new engine in one of the recently completed customer planes in Lakeland this week, and can report that the engine - mated to a DUC Hélices three-blade prop - is a great package. It starts with a little bit of a shake, but smooths out immediately and continues being smooth throughout the flight regime. The airplane handles the same as it did with the two-stroke, with the same stall and slow flight characteristics. Acceleration seems better on the runway, with better climb rates off the deck. Little else appears to have changed about the airplane - which is a good thing, because it was a fun flier already. It's just the kind of plane you want to fly on a nice summer evening, trying for ever shorter landings - or increasingly smooth touchdowns.
Erwin is happy with the HKS package on the airplane, and feels it is the right power plant for the machine - but talking with him after our quick flight, it was obvious that wheels are still turning in his head, and we will be excited to check in with him again to see what new version of this fun aircraft appear. Without a doubt, they will be interesting.