We've been developing this RC airship over the past two years. Features include 1 hr Endurance, 3-5 amp battery, 400g payload, camera gimbal, FPV, Low vibration, crash survivable, Helium recovery
and storage after each day of use.

Some videos:

Welcome to the LED - Long Endurance Dronehttps://www.youtube.com/watch?v=iMPtHGWouNQ
Brushless gimbal - https://www.youtube.com/watch?v=8sqCBWNohug
Servo gimbal and MFD controller - https://www.youtube.com/watch?v=z3glE5syuCI
Over snow - https://www.youtube.com/watch?v=joLNCG17uPU

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Comment by John Rambo on April 1, 2016 at 12:42am

@Marthin H.,

the problem with blimps is -  they can't be small and efficient, just like quad's can't. 


it seems your L/D ratio is 6:1? That's not a shape which gives you a smallest drag possible. I've done a study and, surprisingly, 3:1 is a way to go for near-ground winds. Since blimp is simply a prolate ellipsoid, your volume increases ^2 (squared) while reducing length and increasing the diameter. 

In regards to envelope construction - default material is coated mylar - some 50uM tick. Rcgroups community claims it has lower helium leakage plus is lightweight. Maybe. For indoor use. 

I've made a sealed bag of UV-resistant polyethylene 2 years ago. 200uM tick. Filled it with hydrogen. It keeps the shape still, but lost some surface tension. I wasn't able to damage it even by standing or bouncing with my ass on it (I'm 65kg). Of course, if won't float as its to heavy for its volume.

https://goo.gl/photos/pFR2Af5e5z6fVt2i9

On the other corner, my 20 liter Helium balloon in two years lost 70% of Helium. It diffuses through finger-thick metal more, than Hydrogen does through a polyethylene film (because H2 molecule consists of two atoms).

Conclusions: For longer endurance and cost reduction by 3x, Hydrogen is the way to go. 150-200uM polyethylene. 2-4 m^3 (as your envelope will come at ~1kg).

And sorry, I'm tend to disagree that such quantities of Hydrogen, and they way it is used is more dangerous than any multi-rotor drone with motors of <=1000kV. 

Comment by Martin Hill on April 1, 2016 at 4:51am
Hi John
To clarify
1) L to D ratio is 4
2) Envelope material is different from helium storage material. 1m3 gives 400g payload. Metalisation reduces porosity significantly
3) Helium costs per yr is about £80.
4) Payload is protected by the envelope on heavy landings. More than pays for cost of helium which is stored between flying days.
5) Solar power Possible for all day endurance.

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