I ordered three Aviastar .46s for myself and two flying buddies a few months ago. I brought them out to our club field when I received them to give out to the guys; one of my other flying buddies said he wanted one, too, and I ended up selling him mine.

I did get a chance to break in and tune one of the three engines. One of the guys put his on a Buhor SPAD that he'd built. We had a little bit of glow plug trouble at first, and I found out he'd put an old plug in his Aviastar .46 to break it in. We changed it out to an O.S. #8 and ran the initial break-in tank, alternating the needle from about 1/4 rich of peak to 3/4 rich of peak (typical of most ABC break-in instructions).

After the first tank, I recommended that we go back over the engine and double check the bolts. One of the big differences I've found between expensive engines and inexpensive engines is that the expensive engines seem to stay bolted together better. Sure enough, we found a little bit of play in some of the cylinder head bolts and one of the backplate bolts had started working itself loose. We tightened them back up quickly enough; it was also encouraging to see that the carburetor hadn't started coming loose.

After letting it cool down, we went to restart the engine and discovered that the new O.S. #8 plug had failed. I grabbed a new Fox RC Long plug from my field box (w/ idle bar) and we restarted the engine. The pinch was good after one tank, but no longer too tight to idle reliably. In fact, the idle was solid at around 3,000 rpm. We did a pinch test to get the low-speed needle fine tuned a bit and checked the transition. It was very, very good for a new ABC engine with one tank through it. I told my buddy to go fly his plane.

The Buhor SPAD flew around well enough for about 6 or 7 minutes, and the new Aviastar .46 performed admirably. It was turning an APC 11x6 prop around 12,000 rpms, and it ran beautifully all the way down into the ground. My buddy forgot to put the servo arm screw back into the elevator servo after adjusting his linkage, and the elevator servo arm popped off round mid-flight of his maiden voyage.

The trip into the dirt cracked the carburetor housing, which was a shame because his carburetor had worked great right out of the box. By reputation, that isn't always the case with the Aviastar .46.

My overall impression of the Aviastar .46 was that it was a very solid performing sport engine and a good value for the price. It broke in and tuned easily enough, and the Fox RC Long plug seemed like a really good match for it. Double checking the cylinder head and back plate bolts, especially after the first few runs, would be my only caution. I'd suggest that with any new glow engine, however.

I'd definitely consider ordering more Aviastar engines in the future, especially for projects like combat planes or float planes where I wouldn't want to put a more expensive engine at risk. Also, the larger Aviastar 2-strokes have a good reputation (Sig currently stocks the 1.50 and 2.00 2-strokes), and I think it would be fun to try one of those out on the right project as well.