A320 Electric Jet

[Brian Abraham]

EADS APU-Powered Electric Wheels for A320 Family

Airbus engineers have patented a still-experimental taxiing system for the A320 family, which includes the Airbus Corporate Jet, that uses electrically driven wheels to reduce fuel consumption during ground operations at airports and allow autonomous push backs.

EADS says the system uses electric "actuators" powered by the aircraft's auxiliary power unit (APU) to drive the landing gear wheels. Fuel consumption is expected to be five times less using the APU as compared to using engine power -- saving as much as 200 kg of fuel per flight compared with current airport processes. In addition, this alternative eliminates the need for a tug to push airlines away from the boarding gate.

The demonstration phase of the project is scheduled to close in 2012 with full-scale taxi tests beginning in 2013. If all goes as planned, EADS says initial flight tests will take place the following year.

From Aviation Weeks BCA Bulletin.

[mike-wsm]

Makes a lot of sense if the weight penalty is not too great. Other advantages might include steering by driving the wheels appropriately and spinning the wheels up prior to landing, saving a wee bit of rubber.

[Jane-DoH]

This basic concept is actually very old: Anyone here ever read about Gustave Weisskopf? Either way, the man created an early aircraft, called the Whitehead 21", which was based around a boat-hull fuselage with a pair of wheels, a rudder in the back, wings based on Otto Lilienthal's designs, two tractor propellers driven by a type of steam-engine of his design (which was later used to power trains in Australia if I recall).

Now you might ask: What does this have to do with an A-320 using electrically driven wheels to help it taxi? Well, the Whitehead 21 actually used the engines to spin the wheels for accelerating along the ground initially; as the plane's speed would build, power would be transferred to the propellers prior to takeoff.

[galaxy flyer]

It would be interesting to know the weight penalty--electric motors are not light and there is no use for them once airborne, significant fuel cost carting them around. I am open to the idea.

Can't wait for the Pprune thread, "Crew attempts take-off but forgot to start engines"

GF

[Jane-DoH]

galaxy flyer

It would be interesting to know the weight penalty--electric motors are not light and there is no use for them once airborne, significant fuel cost carting them around. I am open to the idea.

So fuel efficiency would have to outweigh the weight penalty for it to work?

Can't wait for the Pprune thread, "Crew attempts take-off but forgot to start engines"

I can easily imagine this happening. Let's just hope those electric motors can't move the airplane much above 25 knots (I know Ryanair and Southwest would howl at that prospect :E but as I understand, you shouldn't really be taxiing above 25 kts anyway).

[aviatorhi]

That problem (or potential for it) could easily be remedied by having an auxillary throttle for the motors instead of routing it to the engine throttles (probably what they're doing anyway).

We already have too many "stupid pilot checklists" being forced upon crews don't need another 5 because somebody forgot that you need the engines on to take off.

...but as I understand, you shouldn't really be taxiing above 25 kts anyway.

Why the :mad: not... I'm taxiing to get out of an airport, not take a scenic drive.

[300Hp]

at the end of taxi we will stop for good engines temperature?
about 3 minutes.
:hmm:

[mustafagander]

aviatorhi,

Think about tyre sidewall flexing and tyre carcase temperatures for a moment, then contemplate the damage a long, fast taxi can do to your tyres. What is the recommended distance limit again? Just check with the tyre manufacturers. Remember the problems when the reef runway opened in HNL.

Perhaps a 25Kt limit would be a very good thing.

[aviatorhi]

Taking all that into account, in my situation, I disagree that going slowly matters and I have no problem with SWA taxiing like they're "on a mission from god".

[mustafagander]

Stay well away from 400 ton jets then!

[FlightDetent]

Taxi consupmtion CFM 12 kg/min. APU 2 kg/min. Minimum warm up 3 mins. to save 200 kg you need 200/(12-2)+3 = 23 minutes taxi time. To break even need to consider increased fuel burn on each and every sector due weight and maintenance cost.

It may be viable, but "up to 200 kgs" is marketing communication. True, tug cost and flexibility will play a substantial role. For CJ even maybe tug non-availability.

FD (the un-real)