Most aircraft, including the vast majority of small gyroplanes, are equipped with a conventional, "floor mounted" control stick. Back in the late 50's and early 60's, virtually all Bensen Gyrocopters were equipped with an overhead control stick. Because of the geometry of the overhead stick, the control movements required are "opposite" those of a standard stick:

The overhead stick is considered "unconventional" by most pilots - about the worst criticism one can make in the conservative world of aviation. Bensen, who always kept an eye on market potential, responded by developing a conventional joystick, which gradually has come to dominate the sport gyroplane movement. Despite this overwhelming trend, there are still gyro pilots who prefer the overhead stick and consider it a superior control system for small gyros. As ultralight gyroplanes continue to develop, there are some good reasons to revisit the question of the type of control stick geometry. In the sections which follow, I will attempt to briefly summarize the advantages and disadvantages of the standard/conventional and overhead stick.

The advantages of the standard "floor-mounted" control stick all revolve around the "conventionality" of this type of control system:

• Almost all two-seat machines used for dual-control training are equipped with this type of stick.
• If you have flight experience in other conventional fixed or rotary-wing aircraft, control stick inputs will be the same, making for an easier transition to gyroplanes.

There are, however, some distinct disadvantages to the conventional joystick:

• The system tends to be complex. The stick itself can have a multitude of parts (particularly the popular "walking beam"-type stick), not to mention at least two control rods, four rod-end Heim fittings, and associated hardware. This complexity translates to a greater potential for component failure. Such failures, along with other problems than can jam the system in flight, have resulted in a number of fatalities. Most of these could have been prevented with a proper preflight inspection, but the simple fact is there is more to inspect!
• The complexity of the system also results in higher costs. A typical stick assembly can cost between $300 and $500, exclusive of the control rods, Heim fittings, and hardware.
• All of these parts increase the weight of the control system.
• All components have to be carefully adjusted to minimize binding or play - either of which can seriously degrade handling and inhibit precise control of the machine.
• Given the geometry of the system, control inputs in normal flight tend to be made with very small stick inputs. This tends to increase the pilot workload, particularly on long flights, and can lead to over-control.
• The system takes up space below and behind the seat, generally eliminating these areas as places for cargo or equipment storage or mounting.

The advantages of the overhead stick tend to compliment the disadvantages of the conventional joystick:

• The system is extremely simple, with a single rigid stick connected directly to the rotor head. This arrangement is inherently less prone to failure and is easier to inspect. I am not aware of any accidents resulting from failure of the overhead stick, but such failures are certain to be less common in comparison with the standard stick.
• The overhead system costs less - all required materials should not add up to more than $75 - or less!
• The weight of the overhead stick system will be significantly less - an important consideration for Part 103 machines.
• The overhead stick is completely free of binding or play.
• The long lever-arm represented by the overhead stick results in a significantly less sensitive control system, reducing the potential for over-control.
• The space beneath and behind the seat is freed-up for other uses.
• The control inputs are perfectly natural for trike pilots, making for an easy transition to gyros. Given the increasing popularity of trikes, this is a significant factor.

The disadvantages of the overhead stick appear to parallel the advantages of the conventional arrangement:

• Difficult or impossible to get flight training.
• The control inputs are "backwards"/"unconventional" with respect to common fixed-wing aircraft and that makes conventional pilots nervous.

If we could discount the importance of the "conventional" aspect of the standard stick, it is pretty clear that an overhead stick would offer significant advantages, particularly for Part 103 machines. This being the case, lets look at the "unconventional" control issue.

The importance of this issue tends to be amplified by conventional pilots who tend to be quite conservative with respect to all aspects of aircraft design and construction. Here are some very personal observations on these points.

Ease of Use. The control inputs for the overhead stick on a gyro are the same as those required for weight-sift fixed-wings and trike aircraft. These aircraft are typically considered to be very easy and natural to fly - something I can confirm based on many years flying a weight-shift Quicksilver fixed-wing ultralight. Flying with a conventional control stick is more demanding by far!

Confusion? If you have learned to fly with both systems, won't you get confused, particularly in a crisis situation? Without exception, pilots familiar with both systems will answer no! Think about driving for a moment. If you drive with your hands on the top of the steering wheel, you move the wheel one way to make turns. If you grasp the bottom of the steering wheel, these inputs are reversed! The fact is, you don't have to think about it as you shift your hands and about the only way you could make a mistake would be to think about it while driving!

Training. This is a legitimate issue but there is a way around the problem. You can take conventional gyro instruction and then go out and find a trike BFI and pick up a few hours of dual in one of these machines. As long as you are careful and approach flying your own machine in easy stages, there is no reason why you cannot make a safe and easy transition to the overhead gyro stick.

There is no single answer to the "best control system" question. If you want to be conservative, you can simply go with the standard joystick. However, there are some really good reasons to consider the overhead stick option, particularly for an ultralight machine.

This summer (2000) Don and I will be testing an overhead stick on the prototype Gyrobee and the new Honey Bee. Assuming all goes well, I will post documentation drawings for the stick assembly.