Dispatch/operational towing for reducing emissions?

[IHWS]

To me it seems that using jet engines for taxiing is bad for so many reasons: engines are not the most efficient for ground use, source of unnecessary emissions, engine lifetime is wasted and FOD risk, etc...

Virgin Atlantic tried dispatch towing about 15 years ago but it seems it didn't really work out for them that time. However, as time passed, environmental issues are getting more pressing. For instance, ICAO passed a resolution for capping/offsetting CO2 emissions (CORSIA), but there is really no viable alternative fuel for flying.

Do you think that this would make operational towing a viable option? Why is it not being done right now? Or will the associated difficulties continue to keep airlines from doing this?

[Atlas Shrugged]

I thought it was a dumb idea back then..... I don't think I was wrong.

[Junkflyer]

Towing will make a congested airport even more congested.

[Dave Therhino]

You guys aware of Taxibot? I think it is used more to save fuel than for emissions, but the idea is the same.

[stilton]

What do you do with the tug once you’ve reached the runway?


Whatever it is you’ll add to congestion

[Uplinker]

No need for towing. There is e-Taxi for Airbus and WheelTug for Boeing: electric motors in the nose wheel which can taxi the aircraft using the APU Gen, or assist one engine.

Also no need for a pushback tug or towbar, (unless the ramp is icy), just someone on the headset. Save time at busy airports where many have to share the same push crew.

I tried to interest my previous airline in this, but then they went into administration.............

[Skornogr4phy]

The only concern is the weight of the electric motor in the nose gear in that case. If it causes increased fuel burn during flight it might actually increase emissions.

[Uplinker]

[B737900er]

According to Vegans and vegetarians, meat-eaters cause the most damage in regards to climate change.

[petrichor]

Originally Posted by Uplinker

No need for towing. There is e-Taxi for Airbus and WheelTug for Boeing: electric motors in the nose wheel which can taxi the aircraft using the APU Gen, or assist one engine.

Also no need for a pushback tug or towbar, (unless the ramp is icy), just someone on the headset. Save time at busy airports where many have to share the same push crew.

I tried to interest my previous airline in this, but then they went into administration.............

That's going to be one hell of a motor to pull any aircraft over 150T! The weight and stress added to the gear alone would probably make it unfeasible. As for tugs - when under tow the engineer has responsibility for the process including clearance of obstacles and other aircraft - this would not change, which means you now tie up that person for probably 45mins-1hr per aircraft which is not a good use of manpower.

Do we need to do something yes, and RETI is the probably the best compromise so far. The most effective way to cut emissions = less aircraft. The time has come to accept that it no longer makes sense to pursue the ideal that "everyone can fly". They should not. The risks associated with flying justify high safety considerations and that comes at a cost. Unfortunately airlines, manufacturers and regulatory authorities now seem to deem cost/profit margins as more important that safety and that means a reduction in safety margins is necessary just to allow Joe Public to travel halfway around the world for a few bucks! Perhaps the cost of a ticket should have matched inflation all these years, that would have kept the demand down and thus aviation-related emissions. One look at a global view on Flightradar gives a scary perspective on just how many aircraft there are up there at any one time! Yes it would mean less jobs but if we are truly looking at effective ways to cut emissions then we have to look at changing our mindset that an annual holiday abroad or numerous trips for business meetings are an absolute necessity.

My tuppance worth...and yes I'm an airline pilot so I understand the effect of what I'm saying.

[Atlas Shrugged]

All silly. There are much more pressing issues, and this isn't one of them.

[Uplinker]

Originally Posted by petrichor

That's going to be one hell of a motor to pull any aircraft over 150T! The weight and stress added to the gear alone would probably make it unfeasible. As for tugs - when under tow the engineer has responsibility for the process including clearance of obstacles and other aircraft - this would not change, which means you now tie up that person for probably 45mins-1hr per aircraft which is not a good use of manpower.

No, no ! you only need a headset man and possibly a marshaller for the pushback - which is done by the pilots. After the wave off, the pilots taxi the aircraft as they normally do, except using an electric traction motor instead of main engine thrust.

As far as stresses are concerned, the Nose wheel assembly has already been designed and built to be fully capable of taking the full force of towing a max taxi weight aircraft, so it will comfortably handle the push force from the motors. In fact, the motors will be a lot gentler since the motor controller will no doubt have a built in soft start and soft stop, instead of the rough handling of some tug drivers !

The point is you don’t need a tug or a tow-bar, so at busy airports, you save the time involved with disconnecting the tug from the previous aircraft, removing the tow-bar, attaching the tow-bar to the rear of the tug, driving to the next aircraft. disconnecting the tow-bar, attaching it to the aircraft................well, you get my drift. So at busy ramps this could save a lot of time and missed slots.

At airports with long taxi routes and delays, this system could save fuel and CO2.

The system has been built and trialled. Google or youtube WheelTug and you will see.

[tdracer]

Uplinker - how much does such a system weigh? Total - not just the motor but the extra wiring, controls, etc.
500 miles is a short flight - at least on this side of the pond typical flight length for an A320/737 sized aircraft is over twice that (which would proportionally increase the cruise fuel burn due to the extra mass of the system)

[FlightDetent]

You Tube

The video is over 2 year old, not sure if the project actually took off and why not. They have a bucket of arguments if you are looking for the possible pros.

Note that fuel savings is not what's marketed.

[phiggsbroadband]

Have you forgot to factor in the fact that you will be taking off with cooler engines..? A five/ten minute taxy will warm most of the engine lubricant much more than just starting one minute before take off.

[Uplinker]

No, I haven't and I am not the designer of either system.

Have another look at the e-Taxi graphic I posted at #8: The answers to these questions are on there, including 5 min engine warm up.