The Economist looks at a back-of-the-envelope proposal from engineers at Airbus that adapts aircraft carrier technology to civil use:
Mindful that many passengers are already nervous about the whole process of getting a plane airborne, the engineers prefer to call their proposal “Eco-climb”. But the idea is straight out of “Fireball”. The aircraft to be launched would sit on a platform that ran along a track where the runway would otherwise be. The platform would accelerate to take-off speed, at which point the plane would lift into the air powered by its own engines.
[. . .]
Altogether, according to Airbus’s back-of-the-envelope calculations, Eco-climb would reduce fuel consumption by 3% on a typical 900km (560-mile) flight, even with existing aircraft designs. But it would also allow for the design of lighter aircraft, with smaller engines, which would cut fuel consumption, noise and emissions further.
Nor is the idea complete fantasy. General Atomics, an American military contractor, has already built and tested a linear-induction-motor-based system of this sort at an airbase at Lakehurst, New Jersey. The General Atomics system is now being scaled up to be fitted on a new generation of aircraft carriers for the American navy.
Maybe these guys should try harder at figuring out Economics, because they’re making it clear they don’t have a clue about aviation or automobiles.
Forget for a moment the mechanics involved in catapulting an aircraft that weighs anywhere between 130,000 pounds (Boeing 737) and 1,200,000 pounds (Airbus A380) on a huge moving platform capable of supporting that much weight, and remember that operating a motor is (linear or rotary) is about the second least efficient thing you can do with electricity, then think about the cost of the electricity used vs. the 3% in jet fuel savings.
What may be justifiable in the context and scale of an aircraft carrier is an entirely different proposition when applied to the realities of modern airport operations. There’s a reason that the Navy has quadruple redundancy for catapults on aircraft carriers. How many people are going to be enthused by half-day flight delays when airport catapults go down?
With a name like the Economist, one would assume there might actually be some economic analysis applied to the topic reported instead of just printing Rube Goldberg press releases verbatim. The Fireball analogy may be prophetic, albeit in a different way.
Comment by Tom Kelley — October 21, 2012 @ 13:00
Tom Kelly touched on my objection to this problem: operations.
I don’t think it’s possible for a non-military organization to operate catapults on a regular and consistant basis 24x7x365.
Even the Navy doesn’t do that.
Comment by Brian Dunbar — October 21, 2012 @ 18:25
I knew a post like this would draw out the “nattering nabobs of negativism”!
Of course it’s not a serious proposal: it’s from Airbus: it’s a ploy to get a new funding scheme up and running from depleted EU pockets to keep Airbus busy.
But it’d be kinda neat to see them try to work with both the regulatory organizations and the airport operators to get this implemented on a trial basis. Think of all the Euros that could be poured into this endeavour!
Comment by Nicholas — October 22, 2012 @ 07:50
> I knew a post like this would draw out the “nattering nabobs of negativism”!
Haw!
> Think of all the Euros that could be poured into this endeavour!
A full employment for consulting engineers project? Proceed, then!
Comment by Brian Dunbar — October 22, 2012 @ 20:24