That video was fascinating, and really well made (great 3D graphics) - I had no idea mooring the R100 was that complicated!
The R100 is my favourite airship: it had a really fancy dining room (look it up on image search) and viewing lounges - and the lewd designer was Barnes Wallace, later famous for inventing the bouncing bombs in WWII!
>> I had no idea mooring the R100 was that complicated!
Arguably the ground handling infrastructure and manpower requirements to land them safely is one of the main impediments to them making a comeback.
It's a shame, as living within spitting distance of the Cardington sheds and seen the small Airlander hybrid, the actual full size R10* must have been something else. There's some rather nice photos here that gives a glimpse of what that was like for the R100 https://rarehistoricalphotos.com/r-100-airship-pictures/
"A unique example of design. The R101 was fitted with a smoking room on the lower deck able to seat 24 people. The floor and ceiling were made of light asbestos with a thin sheet of metal on the floor. The walls were the same construction as the rest of the ship, being made of cloth. The smoking room was not considered a hazard to the ship as all precautions had been taken with materials in construction. This is where you could retire after dinner and enjoy a cigar and postprandial drink."
An audiobook about R101, a sort of "British Hindenburg," with interesting context about the British airship industry: https://youtube.com/playlist?list=PL0INsTTU1k2Vh4m4jS9oVE7GF... ("Fatal Flight: The True Story of Britain's Last Great Airship" by Bill Hammock)
engineerguy (Bill Hammock) is fantastic, check out the rest of his channel while you're there.
cool video! I wonder what is the smallest practical size for a personal zeppelin? I feel like a small craft would not require such complex docking.
Volume increases as the cube of the diameter while weight goes by the square for the ship's structure itself plus a constant for what it can carry laden, and you'll lose a lot of "volumetric lift" as you bring it down in size. What's the difference in lift/density of hydrogen vs hot air, like in a balloon?
I guess we've never seen them marketed so it's probably impractical. Too bad, good tagline for such a company, to indicate the bespoke nature of such personal transport: "Oh, the human!"
It was clear that some of the lift came from the airfoil, but, you're right, that's most of the lift. It's similar to the Aereon inflatables of the 1960s and 1970s. Some flew, but were not very useful.
> What's the difference in lift/density of hydrogen vs hot air, like in a balloon?
Density data from Wikipedia:
Air @ STP: 1.225 kg/m³
Air @ 100°C (typical for a hot air balloon): 0.9486 kg/m³ → lifting force ~0.2764 kg/m³
Hydrogen: 0.0899 kg/m³ → lifting force ~1.1351 kg/m³
Helium: 0.1786 kg/m³ → lifting force ~1.0464 kg/m³
Subtract the density from air and you get the lift force (mass).
i.e. hot air can lift about 24% as much as hydrogen, or conversely, you need 4 times the volume.
I've often wondered if there might be a more efficient propulsion design using modern materials, using something like a whale's fluke, or some flapping wings. Seems like in addition to personal zeppelins, there's room to innovate with more biological designs.
The trick to efficiency is to accelerate more mass at a lower delta v. Doesn't matter if it's rotating or oscillating. I.e. long flapping wings/tail or long, slow propellor blades. One benefit of an airship is large propellors are more practical than on a small plane.
Propellers are usually up around 85% efficient at their design speed (with fixed pitch propellers falling off very rapidly away from this design speed, and variable pitch props having a flatter optimum). There's room for improvement here, but not a game-changing amount. A larger, slower prop captures most of the potential improvement with far less incremental complexity than something completely novel.
I once read somewhere that an estimated 70% of all technical knowledge has only ever been published in the form of patents.
I always find it fascinating to see these ideas described in detail and with technical drawings in old patent applications, a quick google search results in this one [0] describing a mooring mast, filed by the same company that built the R-100.
The R100 is my favourite airship: it had a really fancy dining room (look it up on image search) and viewing lounges - and the lewd designer was Barnes Wallace, later famous for inventing the bouncing bombs in WWII!
https://en.wikipedia.org/wiki/R100