United787 From United States of America, joined May 2005, 2344 posts, RR: 1 Posted (7 years 9 months 3 weeks 3 days 18 hours ago) and read 5627 times:
Please forgive me if this has been discussed, I have not been able to find a thread on this subject but...
I just read that Boeing is testing an electric motor on the nose wheel of an AC 767 that will allow airplanes to operate on the ground without the use of engines or ground tow tugs. See link:
My first thought is DUHHHHHH. Why didn't anyone think of this before. I am sure it is more complicated than that, but such a simple concept would seem to have such huge benefits you would think Airbus or Boeing would have figured this out like 30 years ago. Please help me to understand why airplanes don't already have this feature.
DC10GUY From United States of America, joined Feb 2000, 2685 posts, RR: 7 Reply 1, posted (7 years 9 months 3 weeks 3 days 18 hours ago) and read 5563 times:
Wow, great idea. Are they planning to add this to newly built airplanes ??? or old ones too ???
Next time try the old "dirty Sanchez" She'll love it !!!
DLKAPA From , joined Dec 1969, posts, RR: Reply 4, posted (7 years 9 months 3 weeks 3 days 17 hours ago) and read 5450 times:
Quoting Ruscoe (Reply 3): Weight might be a problem.
Ruscoe
For an electric motor to be able to produce enough energy on the nosewheel to allow the plane to move forward, yeah that thing is gonna be pretty big. I'd like to see it even retract into the wheel well.
Sean1234 From United States of America, joined Aug 2000, 411 posts, RR: 0 Reply 5, posted (7 years 9 months 3 weeks 3 days 15 hours ago) and read 5298 times:
How about some ducted air design running off of the APU? BTW I'm not an engineer.
Captaingomes From Canada, joined Feb 2001, 6413 posts, RR: 58 Reply 6, posted (7 years 9 months 3 weeks 3 days 15 hours ago) and read 5267 times:
Oh no, they're making a Boeing FWD instead of RWD. That's no fun!
The concept is fine, but I too wonder about weight and size issues. This electric motor has to be mighty strong. Think about the size of the tugs and the power they generate to efficiently move a 767, now imagine what sort of built-in device would be required to do the same job? Perhaps this will go the way of the folded wings from the 777, it may be made an option at some point, nobody will take it, and it will go down in history as a good idea in theory but not in practice. Just my humble opinion though.
"it's kind of like an Airbus, it's an engineering marvel, but there's no sense of passion" -- J. Clarkson re: Coxster
GEnx From United States of America, joined Jun 2005, 67 posts, RR: 0 Reply 7, posted (7 years 9 months 3 weeks 3 days 14 hours ago) and read 5208 times:
Actually, electric motors can produce tremendous torque, which would work for an aircraft application, where you are just trying to get the plane moving slowly on the ground from a stop. The big question is power source. The assumption seems to be the APU, but will their be alot of intermediary hardware/software necessary to control the system? That's the complexity/cost/weight issue. How much gas saved on the ground to offset the other penalties?
GEnx From United States of America, joined Jun 2005, 67 posts, RR: 0 Reply 8, posted (7 years 9 months 3 weeks 3 days 14 hours ago) and read 5183 times:
And I wonder what the 'Flight related' technical issues are if this a ground based system?
UAL747DEN From United States of America, joined Dec 2003, 2225 posts, RR: 13 Reply 9, posted (7 years 9 months 3 weeks 3 days 13 hours ago) and read 5109 times:
Attaching a motor to something that slams into the ground and goes from stop to couple hundred miles an hour would be mighty complicated, the less moving parts on the plane the better, I don't think we will see this for quite a while
Euclid From South Africa, joined Apr 2005, 372 posts, RR: 0 Reply 10, posted (7 years 9 months 3 weeks 3 days 10 hours ago) and read 4962 times:
I can't see how this could ever work. Never mind the things like extra weight, etc. What bothers me is the fact that they put the motor in the nose gear. Most of the plane's weight rests on the main gear, as we all know, so how on earth would the nose wheel have sufficient traction to pull a fully laden plane forward? I would think, especially on a wet tarmac, that the nosewheel would just start spinning and the plane wouldn't move an inch. Imagine pilots bragging about the burnouts they did!
Using electric motors is a good idea, as they are immensely powerful, but I think this would work a lot better fitting two smaller motors in the main gears than to fit one big motor in the nose gear.
YYZAeroEng From Canada, joined Jun 2005, 165 posts, RR: 1 Reply 11, posted (7 years 9 months 3 weeks 3 days 8 hours ago) and read 4890 times:
Quoting Euclid (Reply 10): can't see how this could ever work. Never mind the things like extra weight, etc. What bothers me is the fact that they put the motor in the nose gear
Why would something like that bother you? From the article it seems that Boeing/chorus engineers have proven your doubts wrong. The test was performed under a variety of condition, and it has shown its potential.
Quoting Euclid (Reply 10): would think, especially on a wet tarmac, that the nosewheel would just start spinning and the plane wouldn't move an inch. Imagine pilots bragging about the burnouts they did!
Since electric motors are known to produce exceptionally high torque, I don't imagine burnouts would be a problem. The spinning of the wheel would be caused by trying to accelerate too quickly, with the proper application that shouldn't be a problem.
I think exploratory technology like this will go a long way in making air travel more efficient
Revelation From United States of America, joined Feb 2005, 10452 posts, RR: 20 Reply 12, posted (7 years 9 months 3 weeks 3 days 5 hours ago) and read 4774 times:
Maybe they could use the load of the electric motor to help in braking, and use the energy generated to help recharge the battery, just like hybrid automobiles do. I better go call the patent office now!
N867BX From United States of America, joined Nov 2004, 339 posts, RR: 0 Reply 13, posted (7 years 9 months 3 weeks 3 days 1 hour ago) and read 4504 times:
I wonder how the cost of this idea compares to the cost of a pushback tractor.
Wingman From Trinidad and Tobago, joined May 1999, 1836 posts, RR: 5 Reply 15, posted (7 years 9 months 3 weeks 3 days ago) and read 4259 times:
How about a bolt-on model and just use it on departures? Fuel savings are probably more imperative on the long queues waiting for take-off clearance. Just before final line-up it gets removed and hauled back to the terminals for the next plane. Even if you need different models for each plane type you'd still save millions on the number of reduced units required.
StarGoldLHR From Heard and McDonald Islands, joined Feb 2004, 1529 posts, RR: 1 Reply 16, posted (7 years 9 months 3 weeks 3 days ago) and read 3868 times:
Heres a radical idea.
We all know that vacuum cleaners can be set to automatically follow a line on the ground.
Why not develop an "auto-tug" which recieved via radio it's command / route to push back a plane and guide it to the runway for takeoff following lines on the ground, then detach, and await to pick up the next landing plane and automatically take that plane back to the gate.
This saves many things:
1. Engine Fuel on the ground
2. Need for people to push back
3. Safer control for getting aircraft / distances etc around the airport
4. If this was electric/rechargable.. it's ultra energy efficient
5. Saves need for excess weight on the plane
remember.. you saw it first here
So far in 2008 45 flights and Gold already. JFK, IAD, LGA, SIN, HKG, NRT, AKL, PPT, LAX still to book ! Home Airport LCY
AirportGal From United States of America, joined Feb 2005, 73 posts, RR: 0 Reply 17, posted (7 years 9 months 3 weeks 3 days ago) and read 3855 times:
not only would it eliminate the volume (and weight) of fuel needed to taxi from gate to runway, the amount of engine exhaust and noise would be reduced as well.
Dimsum From Canada, joined Jan 2005, 91 posts, RR: 1 Reply 18, posted (7 years 9 months 3 weeks 3 days ago) and read 3808 times:
Quoting Wingman (Reply 15): How about a bolt-on model and just use it on departures? Fuel savings are probably more imperative on the long queues waiting for take-off clearance. Just before final line-up it gets removed and hauled back to the terminals for the next plane. Even if you need different models for each plane type you'd still save millions on the number of reduced units required.
How would this be any different and MORE practical than the existing tow-tug system?
Checkraiser From , joined Dec 1969, posts, RR: Reply 19, posted (7 years 9 months 3 weeks 2 days 23 hours ago) and read 3662 times:
Quoting Boeing Nut (Reply 14): Seems to me that this is a bit redundant with electric powered tugs anyway. A good idea non the less.
You cut out the person driving the tug and having to attach and release the towbar. Less time involved - and we all know time is money.
Quoting Euclid (Reply 10): What bothers me is the fact that they put the motor in the nose gear.
I don't know any better than the next guy but I imagine the motor would be located inside the A/C and connected via some sort of gearbox and linkage system.
Quoting Euclid (Reply 10): I think this would work a lot better fitting two smaller motors in the main gears than to fit one big motor in the nose gear.
I like this idea too but two motors + two drivetrain assemblies = more weight and money.
Quoting Revelation (Reply 12): Maybe they could use the load of the electric motor to help in braking, and use the energy generated to help recharge the battery, just like hybrid automobiles do.
A good idea as well but I don't think there's any benefit from this. The APU is already going to be running so there's no need to further charge the batteries.
Brake wear should also be reduced because the crew is often times riding the brakes when the A/C is being moved by thrust. The brakes should be used a lot less on taxi now with this system.
FriendlySkies From United States of America, joined Aug 2004, 4003 posts, RR: 6 Reply 20, posted (7 years 9 months 3 weeks 2 days 23 hours ago) and read 3485 times:
Quoting StarGoldLHR (Reply 16): Why not develop an "auto-tug" which recieved via radio it's command / route to push back a plane and guide it to the runway for takeoff following lines on the ground, then detach, and await to pick up the next landing plane and automatically take that plane back to the gate.
Because if the thing went hay-wire, you'd have quite an expensive mess to clean up.
ALB2ATL From United States of America, joined Feb 2005, 88 posts, RR: 0 Reply 21, posted (7 years 9 months 3 weeks 2 days 22 hours ago) and read 3250 times:
Quoting Revelation (Reply 12): Maybe they could use the load of the electric motor to help in braking, and use the energy generated to help recharge the battery, just like hybrid automobiles do. I better go call the patent office now!
Francoflier From France, joined Oct 2001, 3195 posts, RR: 10 Reply 22, posted (7 years 9 months 3 weeks 2 days 22 hours ago) and read 2921 times:
I don't know much, but if the fuel consumed during taxi was such a crippling problem that aircraft manufacturers would have to put heavy electric motors on their planes to taxi them around, wouldn't more airlines have their jets taxi around with only one engine on, say, as an interim mean of saving that fuel?
But I see them all lighting up all 2,3 or 4 burners right at the pushback...
Looks like I picked the wrong week to quit posting...
Euclid From South Africa, joined Apr 2005, 372 posts, RR: 0 Reply 24, posted (7 years 9 months 3 weeks 2 days 21 hours ago) and read 2595 times:
Quoting Checkraiser (Reply 19): I don't know any better than the next guy but I imagine the motor would be located inside the A/C and connected via some sort of gearbox and linkage system.
All electric drives that I have ever seen locate the motor in a housing right on the wheel where it drives the wheel directly, although in some applications there may be gearing involved as well.
Up to 1999 I used to work as an earthmoving mechanic and did a lot of work on the huge mining dump trucks that uses diesel-electric propulsion. The diesel motor (V16 Cummins) would drive a generator that would in turn supply the power to the electric motors, one motor on each rear wheel, driving the wheel directly.
The only reason I have my doubts about using this type of arrangement in the nose gear is that I cannot think how the nose wheels can maintain enough traction on the tarmac to start pulling a plane weighing a couple of hundred tons without spinning, but I'm sure the clever people developing the system would have thought of that and know something that I don't.
Cheers all!
Euclid
25 Oakmad: As for traction control; well they've been doing it for years in with diesel/electric trains. Now obviously the scenario's are a little different but
26 Md80fanatic: Where will a aircraft get the tremendous wattage necessary to run this taxi motor? I don't think batteries will do so well, as the current (charge rat
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