A flight of fancy

I have long been a fan of airships.

The ones we remember most are the German Graf Zeppelin and the ill-fated Hindenberg. Britain built the R100 and then the R101 which crashed and burned in France on her maiden voyage. America had the Akron, Macon, Shenandoah and Los Angeles among many others. The Norwegians and the Italians were also into airship technology.

The Americans held the upper hand as far as airship development was concerned because they controlled the worlds (then) only supply of helium gas leaving the rest of the world forced to use hydrogen. Whilst helium wasn’t quite as good a lifting agent as hydrogen it was a zillion times safer. Look what happened to the Hindenberg and the R101.

There are some excellent websites with photographs of the passenger experience aboard the great airships. Try www.nlhs.com/interior.htm or just Google (Images) ‘airship cabin’. Weight was a major factor in airship design but the largest carried around 100 passengers and crew and provided private cabins to sleep in, a dining room, promenade decks, in one case a grand piano and (since everyone smoked in those days) a smoking room despite the fact that they were surrounded by something like 7 million cubic feet of inflammable hydrogen!

The sheer size of the airships was breathtaking. The USS Shenandoah was just under 800 feet long (3 times the length of a Boeing 747) and 130 feet in diameter. She could carry, launch and recover a fighter aircraft.

The idea of lighter than air flight hasn’t gone away. The Good Year blimps carrying up to 12 passengers on sight-seeing trips have been around for years. A company called Aeroscraft in America is planning a gigantic airship where 2/3rds of the lift is achieved by 14 million cubic feet of helium whilst the remaining lift is provided by engine power and forward motion. They are talking about a 500 ton payload. See http://www.aerosml.com/main.htm

The proposed Aeroscraft airship built to carry a 500 ton payload

My own theories are much more modest. I envisage a 150 foot long by 40 foot wide gondola half of which is taken up by 50 small 2 berth cabins for 94 passengers and 6 crew while the other half comprises dining/lounge/bar and promenade areas.

A rigid frame gas envelope would be around 400 foot long with an oval cross section 60 foot high by 120 foot wide. The envelope would contain no machinery or moving parts leaving it capable of being quickly detached from the gondola for easy maintenance. The envelope would contain a number of oval, doughnut shaped ballonet’s filled with helium with a separate air bag running through the central core of the ‘doughnuts’ where air will be heated to increase or decrease lift as required.

Construction of the envelope frame and the gondola would use light weight carbon fiber composites.

Power would be provided by two light weight, high speed diesel generators using bio-fuel and driving 4 independently gimbaled ducted electric fans attached to the sides of the gondola to provide a combination of lift and thrust, steering and trim.

The rigid frame construction of the envelope will allow operating speeds up to 150 knots at 12,000 feet with the shape of the envelope providing additional lift.

150 knots means London to Sydney non-stop in 48 hours or so or London to New York in around 18 hours and for a fraction of the cost and environmental damage that a jetliner creates. It takes 20+ hours to get to Sydney using an airliner today. Add at least 24 hours for rest and recuperation. An airship taking the same time in total but offering proper sleep, relaxation and space to move about during the flight must surely be a viable alternative particularly when it comes to cost and passenger comfort.

A flight of fancy? I wonder?