I am a US Aircore Colt 40 Turbo user from Greece and about 2 years ago I had requested some advice from you. I want to contribute to your site with some photos of my Colt. I have flown in for 1.5 year and generally I am satisfied with it. I use an OS Max .46 engine and I found out that a 10.5x7.7 propeller gives the best performance with very good vertical performance and outside loops. Also, the plane is really tough and durable and in a crash it suffered it was ready to fly again in a couple of hours.
Main drawback of the plane is its increased weight. Don't consider flying with an engine smaller than .46 and with a .61 or more the plane will have outstanding performance. Although the plane is extremely durable, some parts suffer more. One of them is the landing gear. After one year of flying I replaced it with an aluminum gear. The other weak point is the power cartridge that breaks in a serious crash. It is easy to construct some cartridges from plywood, using the original as a template.
Another problem with Colt is in the case of an engine stop. The plane sinks fast and you have limited time and space to glide, so you must land immediately. I found out that some weights in the tail improve the gliding but you must be careful in dead-stick landings.
John Mademlis
Greece