Rand Robinson KR-1 Crashable?

[cub builder]

Much of what has been said about the KRs here is true. Unfortunately, Ken Rand died decades ago, so on paper, the the plane never evolved. However, in the builder community, the plane has indeed evolved into a better performing safer aircraft. The allure of the KR series of aircraft is the low cost and pay as you go build it all from scratch. Thus, many of the KR builders are trying to scrimp and save pennies. That was my situation 20 years ago when I built one. At this point in time, I have nearly 1100 hours on my KR with nearly 20 hours in the last 2 weeks, and can truthfully say it is one of the most enjoyable planes I have ever flown. I fall in love with it all over again with every flight. I should also note that over the years I have made substantial modifications to the plane to improve it's handling and performance.

The KR-1 and KR-2 were both dynamically unstable in pitch with an extremely light elevator that often times lead to over-controlling on the first flight. If you really want to build a single seat KR, build a -2S, then narrow the fuselage down to whatever width you desire. Join the builders forum KRNET.org and by all means check out Mark Langford's and many other builders web sites linked from krnet.org. There are a lot of significant improvements documented on these web sites that make for a much safer aircraft. The most significant that is in the plans is a larger tail and longer fuselage of the -2S. That makes a significant contribution to stability. On the web sites, you will also find other improvements. Fixed gear is almost a must as it is lighter and more durable than the original retracts, and properly faired, is less drag. That's a winner all the way around. There are plans for a different wing that is cleaner than the original wing design. There are plans for a different tail that has a real airfoil to it and should be built to be significantly larger than the -2S plans tail, which really tames the aircraft. There are plans for flaps and/or belly board for deployable drag, which makes the aircraft significantly easier to land. You will see KR aircraft sporting all kinds of engines, VW, Corvair, Jabiru (both 2200 and 3300), Continentals, Lycomings, and nearly anything else you can name. I'm not a big fan of auto engines in these aircraft as the number of forced landings with them seems to be higher than acceptable to me, but many are flying them reliably.

As for the crashability of the aircraft, many are badly damaged and written off following a crash. However, the wooden structure does a good job of absorbing impact forces while the airframe breaks apart. I personally have not tried that yet, but have seen the after results of a few.

Also, don't be drawn in by the advertising. There are KRs that will go 180 mph (mine is one of them, but that's not cruise), and not on a VW engine. There are some that can get off short and land short, but those are very light and not long distance cruisers. There are some with long cruise range, but they aren't going 180 mph either.

As designed, it's not a great aircraft. But with the help of the builder community, it can be built to be a nice flying, fast and sporty, inexpensive aircraft.

-Cub Builder