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The “T” Bar Cyclic Design

Since purchasing the very first R22 that was sold (serial number 003 in October 1979), the most often asked question of me has been about the R22’s unique “T” bar cyclic design. Even today, when pilots climb into an R22, R44 or R66 for the first time, the cyclic is the number one topic of discussion. Many people think the purpose of the “T” bar design is an attempt by Frank Robinson to stay consistent with his design philosophy of “make it simple, make it light and make it reliable”. Certainly, the design is very simple since there is only one cyclic control linkage instead of two and this will, obviously, save weight. However, the main reason for the R22’s cyclic design is to increase the amount of lateral cyclic travel available to the pilot in order to desensitize cyclic control in the roll axis. Small helicopters naturally have very sensitive cyclic control. If the cyclic extended up from the floor, like most conventional control systems, the amount of lateral cyclic movement would be limited by the pilot’s legs in a small cockpit such as the R22. By allowing the cyclic grip to pass over the pilot’s legs the “T” bar design increases the total cyclic travel to 14 inches. This means more lateral cyclic can be built into the control linkage which will reduce the sensitively of the cyclic. The US Patent Office issued Frank patent No. 4114843 in 1978 for the “T” Bar design.

There are a couple of other nice things the “T” bar design provides. Getting in and out of the helicopter is so much easier without the cyclic control protruding up from the floor. It borders on acrobatic for me to climb into the cockpit of an MD-500 or a BH-407 because of the cyclic. Additionally, the “T” bar allows the pilot to adjust the cyclic grip so the forearm can rest on the right thigh providing a very stable platform for cyclic imputes. For someone new to a Robinson helicopter there is a short period of adjustment but, since the cyclic imputes are exactly the same as in other helicopters, the transition is not difficult.

Certainly, in the R44, which was introduced in 1993, the need to desensitize lateral cyclic control is not as important as in the smaller R22 and the wider cockpit would allow more travel for a conventional cyclic. However, the entire design of the R44 was based on the R22’s proven design principles. The R44 is just a bigger R22, so the “T” Bar design continued. By 2010 when the R66 was certified, the “T” Bar design had become a Robinson hallmark and together with the ease of entry/exit made it an easy decision.

Tim Tucker

Updated March 2020

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