Aeronautical Engineering/Fast Hybrid Airships possible?
There are several interesting modern hybrid airship designs being designed and tested in recent years. The speed of these airships is still limited to 100 knots or less.
How would one go about designing a fast STOL hybrid airship- with a cruising speed of 200=350 knots?
On approach is to build a streamlined airship with a design limit of 4g and fit it with powerful jet engines.
Another approach is to take a working airframe design such as a 747 or a Guppy and fill it with helium to obtain some lightness.
Is it the large cross section that makes this difficult to achieve? What about structural rigidity at high speeds?
If you need a further clraification of ideas please let me know.
I always hate to say something can't be done. But a fast airship sounds unlikely. To make it able to withstand 4g acceleration would require heavy structure, which is counter to the airship buoyancy (not to mention the heavy jet engines). And the drag of such a ship at high speed would be huge. Putting helium in an airplane would require large empty volumes that are not available. I am willing to accept the fact that airplanes go fast and airships go slow and each have important missions.