Balsa USA 1/3 Scale Sopwith Pup built by Howard Crispin

I bought this Pup from Howard Crispin's family. Howard was the District IV AMA VP until he passed away last year. Howard was a consummate builder, but he didn't fly very much. This Pup has reportedly been in construction for about 10 years. It is currently powered by an unknown engine of unknown size. It says "Homelite" on the carburetor (which faces forward) and has the same external dimensions as a Quadra 52, but I've only gotten it to turn a 20x6 prop in the mid 6000 RPM range so far, so I'd guess it was more like a 35 or 42 cc.

Howard had completed most of the structure and had covered it and begun to paint it. I had to rig the flying wires and install my radio system and ignition battery. I had problems with interference from the ignition system at first, but I replaced the wire throttle push rod with a Sullivan carbon fiber one, moved the ignition battery in front of the firewall, and moved all of the radio gear into the cockpit. Now everything is fine. I had to add about 3.5 lbs of weight to the nose to get it to balance.

It has flown a few times so far, and its a bit underpowered (with the engine not running right), but a 30 lb airplane in the air is impressive just flying ovals!

After I get the engine sorted out, I need to finish putting on the markings (I'm going to use vinyl ones), install the pilot, gun, and windscreen, and any additional details. Howard installed the scale control horns and was planning on putting on simulated scale control wires, but I haven't figured out how to do that yet in a way that will work.

This is a picture of Will Dirickson's Pup at the Joe Nall flyin in 1995. I'll post some pictures of mine as soon as I get some...

UPDATE May, 1998

I finally gave up on the Homelite engine after putting a new ignition system on it and it still didn't run well. I purchased a Zenoah G-45 for it. It turns a 22X6 Zinger prop on it at 6400 RPM. This seems to power it in a very scale fashion. I now have 4 more flights on it and I'm getting used to it. It handles like a ton of bricks, but looks good in the air. I plan on taking it to the Danville Rally of the Giants in June.

UPDATE September, 1998

I flew the Pup at the Danville Rally of the Giants twice, and everything went well for the most part. There was a strong crosswind though and when I landed on the concrete runway, the tire came off of the right wheel and the wheel rim was pretty badly bent. I was able to straighten it fairly easily by hand, but I haven't been able to get all of the "wobble" out. It still works fine though. I've flown the Pup about 10 times more and its quite fun to fly and always impresses the spectators. All I need to do now is finish the markings. For that I'll need about three rolls of red, white and blue Century 21 fabric. Its on my list...

UPDATE June, 2000

I finally broke down and put the markings on. Here are some shots of it flying at the Harrisonburg IMAA flyin in June of 2000. Thanks to my friend Will Dirickson, for the pictures (except for the picture of me flying it) and for supplying the shade for all our IMAA event trips!