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I am working on a project to create a mid-size airship having a payload of 25kg. I am in a bit of problem regarding choosing the appropriate landing gear design for it.

Which design would be better, considering the tradeoff with weight, which is a very important parameter. Is using 2 wheels to stabilize my system further worth its weight penalty, or a single wheel would be better like Zeppelin?

I would appreciate any help.

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    $\begingroup$ An airship that small doesn't need landing gear at all. Put a skid on the belly of the gondola and call it good. $\endgroup$ – Edward Falk May 28 '15 at 18:25
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    $\begingroup$ True. But the project is just a model which we plan to scale up. $\endgroup$ – Manish Jun 1 '15 at 10:05
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Two wheels side-by-side would only be needed if the craft is in danger of tipping over sideways. Airships should stay upright because the lifting gas will still provide most of the lift, and the wheel is only for carrying the remaining load. It can swivel for ground maneuvering when the airship needs to swing into the wind while mooring at the mast, but will neither absorb big landing loads nor carry the craft at high speed, so it can be kept small.

On the lower tailfin you should only provide a bumper for unintended ground contact; adding a second wheel would only make sense when the ship touches the ground with both wheels when level. This would be a bad design, however, because maneuvering will be much easier when the lower tail fin provides enough ground clearance to allow pitch angles of approx. 3° - 5°. Note that the lower fin on most Zeppelins was smaller than the upper fin; only the last, less slender ones could afford equally sized fins. In that case, however, you need sufficient propulsion power to keep the cruise speed well above the reversal speed.

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  • $\begingroup$ "Airships should stay upright because the lifting gas will still provide most of the lift": If you never plan on deflating the airship, then sure... $\endgroup$ – Sean Oct 28 at 1:29
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Some full-sized airships have three wheels in a tricycle arrangement, such as this wikipedia photo link.

Others have just two, such as the Zeppelin NT - one for weight bearing, and a smaller tail wheel which appears to be there to keep the tail from fouling on the ground.

I'd suggest, for the size you're planning, you just go for the minimum possible. Only worry about wheels if you will need to taxi it or steer it into wind.

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    $\begingroup$ The tricycle arrangement is only for ground handling with deflated envelope. For operations, a single wheel should be sufficient. $\endgroup$ – Peter Kämpf May 28 '15 at 5:21
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    $\begingroup$ Photo of a Zeppelin NT on the ground: efalk.org/Eureka/bigs/dsc_001.jpg.html $\endgroup$ – Edward Falk May 28 '15 at 18:27

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