Found this Bensen with floats !

Amphibie

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Aug 24, 2017
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France
Hey everyone

I came across this gyro not too far from where I live... It has no more engine and has never flown with these floats (recently homebuilt).

As I've never flown anything except serial manufactured aircrafts, I would love your opinion about the airworthiness of this gyro, maybe someone recognize this version (all I know is it's a Bensen) ?
 

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WaspAir

Supreme Allied Gyro CFI
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Oct 21, 2006
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Colorado front range
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Bell 47G-3B-1 / A&S 18A / Phoebus C, etc.
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stopped caring at 1000
Approach float operations with caution, and not just for the learning curve of on-water operations. Floats add side surface area well below the c.g., and can greatly increase the tendency to get adverse roll with yaw (e.g., left pedal inducing right roll). They also add substantial drag to an already slow draggy design, and can negatively influence fuel range.
 

WaspAir

Supreme Allied Gyro CFI
Joined
Oct 21, 2006
Messages
4,377
Location
Colorado front range
Aircraft
Bell 47G-3B-1 / A&S 18A / Phoebus C, etc.
Total Flight Time
stopped caring at 1000
On a related note, you might have to worry about what it weighs. I didn't see any N-number on it, so perhaps it has been deemed an unregistered ultralight when flown in the past. It's harder to imagine it still being a legal ultralight with the weight of the floats added (unless perhaps you boat-tow it as a glider, without engine), so it might need to be registered, which could get tricky if the original builder is no longer on the scene.
OOPS - just realized that they don't count float weight for UL -- so never mind about that. It is a challenge nonetheless to keep things under the max permitted weight, requiring a minimum of everything.

Personally, the Bensen safety record overall is pretty dismal, and that has kept me away from them. Others here love them.

Everybody here will join a chorus of "go get some good training before you try to fly it", ultralight or not.
 

Doug Riley

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The stock Bensen with floats has a pretty lethal configuration. The floats act as drag chutes, located far below the aircraft's CG. They try to pull the gyro into a vertically nose-down position. The faster you fly, the worse this effect is.

The problem existed even with the old 1930's autogyros, which were otherwise quite stable. One float-equipped autogyro of that era flipped upside down in the air. Probably because of the nature of its rotor suspension, it reverted to upright flight and landed safely. A modern gyro with an underslung teeter hinge will not fare so well once it's upside down and experiencing reverse flow into the rotor disk.

A gyro friend of mine got into float Bensens. He flew his first in the towed gyroglider configuration, then added an engine. He then experienced an uncommanded dive into the waters of Long Island Sound. He landed in the hospital, but survived. There have been other nose-dives of float-equipped Bensen-style gyros whose pilots did not make it.

Bottom line: a float gyro needs to be designed from the ground up, and tested first with models and them the real thing. A safe design would be a big R&D project.

The stock land-based Bensen is not a particularly user-friendly, stable craft. It, too, tries to flip upside down under certain circumstances. It can be made safer with frame alterations and different tail surfaces. As Wasp says, the stock version killed scores of people (the kill yield got up to about one a month for awhile in the late 60's).

Other scores of people have accumulated thousands of hours in them, but you have to watch your back when flying one. There are safer designs on the market today.
 
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