I am going to attempt to here explain some of the mechanical aspects which, make the complex systems ill advised for the Glass Goose.

The gear systems on most aircraft are designed for that specific aircraft. It is true that in SOME few cases, a gear system from one type of aircraft has been found to be almost totally applicable to another design. Most of the time the truth is that the gear was ADAPTABLE to the other design, but required moderate to substantial modification to make it work. Designing the mechanical aspects of a retractable gear system can be a very challenging endeavor. What seems like it should be very simple on the surface can involve very minute nuances of design that make the difference in the system working or not working, or being dependable and not being dependable. To look at the Glass Goose mechanisms, they seem very simple, so what’s the big deal? Well, in fact, they are not simple. They are fairly precise mechanisms. I spent a lot of time redesigning these systems to overcome the failings of the Seahawk design.

The drafting board was not always enough. Many changes were the result of painful gear up landings, or the discovery that the gear would not retract in flight when it did fine in the hanger during static testing. There was the time the gear would extend just perfectly time after time while sitting in the hangar, but it would not extend at all in flight! Each one of those events and changes was born out by good solid reasoning when thoroughly analyzed, but only experience was going to expose the facts upon which the reasoning could be based. This is usually called "trial and error". NASA know Bell Helicopter knows about it. If you think you are good enough an engineer to design something 100% right the first time, you need to talk to some of those folks. There are a lot of good people that paid the ultimate price for what the engineers DIDN’T know. What education or pure IQ cannot reveal experience will.

In this "retracted" position the legs form a flattened "V" similar to the "V" formed by the blades of a pair of open scissors. The "V" or scissor of the upper link and the spring assembly are in a very "stressed" position when the gear is retracted. The weight of the wheels, brakes, axles and gear leg are applying force downward or vertically to the ends of the "Scissor". The only thing keeping the ends of the Scissor from opening up is the hydraulic pressure holding them closed from the other end. It takes approximately 1700 pounds of hydraulic pressure to pull on those linkages hard enough to actually retract the main gear legs fully! (Most of that pressure is required by only the last inch or so of retraction.) BUT, that is at STATIC loading. When landing on water, that 1700 pounds can be magnified as much as 8 times by the impact with the waves! That could mean as much as 15,600 pounds of force required to hold the gear leg up against the bottom of the wing! This would be a very unusual circumstance, but none the less, a possibility and I can tell you it has happened.

There are few of the components of the retract system that could withstand 15,000