Then how did an aluminum aircraft contacting a building cause enough of a spark to cause an on-impact jet fuel explosion?
Indeed we easily could find some pre-existing videos of pressurized cylinders exploding and there being flames. I don't think you're going to convince me that flammable pressurized canisters do cannot cause thrust when punctured.
Does there have to be another existing fire for punctured [propane] tanks to rocket upward like in the movies?
If positioned in a fixed location over critical energy infrastructure , this drone is on another level.
Rockets that contain hydrogen have self-destruct, and NASA doesn't want to load a rocket with Hydrogen while astronauts are onboard on the ground; though rocket fuel hydrogen is chilled and pressurized with lots of energy.
The true cost of guarding a hydrogen blimp that's guarding the critical infrastructure? Is it as much as guarding an upriver reactor cask that's under ordinance spec?
Compared to grid scale battery farms for energy storage, would
Gravitational Potential Energy and/or CAES Compressed Air Energy Storage (which are less lossy, anyway) be less of a liability if in the flight path of a slow to fixed hydrogen airship?
Aerospace-grade [hydrogen, jet fuel,] tanks are probably more impact resistant than any airship ever?
Which critical energy facilities have procedures for handling a hydrogen airship in their airspace with and without a wind event?
Gravitational Potential Energy in old mines is enough energy storage for domestic US needs FWIU, but supercapacitors or ultracapacitors may be necessary to handle renewable load spikes when the sun shines across the grid.
A broken light bulb or a spark on the ceiling are enough to ignite Hydrogen; and that is why facilities that process it must have ventilation.
"A covered Hydrogen filling station must have electricity for ventilation." Agree or disagree?
And what about microwave energy beaming? Can microwave wireless energy transfer cause a hole in an airship? What about freak lightning storms while inspecting high energy power lines in a balloon filled with flammable and explosive gas?
It looks like it may be possible to store Hydrogen in Sodium Bicarbonate.
There are aerospace-grade hydrogen tanks that aren't supposed to explode in a crash landing, but what about midair collision and war?
There are people working on drones that hover in midair (that do not add flight and ground risk) that efficiently use the air currents too.
I'm afraid [this airship firm] hasn't done a sufficient level of testing to determine how easily the product can become a war liability, and I don't think FAA should clear Hydrogen airships for energy infrastructure inspection.