Acft taxiing back to gate with one engine running

[fusion_defusion]

Hi ,
I have seen many ATR's taxiing back to the gate only on one engine, is this normal?, I have heared somewhere that, in a multi engine acft wear and tear should be close to equal on all the engines?.

Airline companies want to save fuel?, in long term, will it not cost more that they have to service a worn out engine?

Just a thought, may be i am wrong.

[TightSlot]

Can't be certain, but there's a small chance that they might have calculated all that before they made the decision to implement single-engine taxi procedures?

[McGoonagall]

I have heared somewhere that, in a multi engine acft wear and tear should be close to equal on all the engines?.

Taxi on alternate engines each landing.

[Lord Spandex Masher]

I think you'll find that the engine is still running but the prop has been stopped. The engine can then be used as an APU.

As far as wear and tear it's rare to find one aircraft with the same engines as it started life with. Engines changes don't always happen in pairs, or fours. For instance, if an engine has a bird strike you won't change both just the damaged one (if it needs it).

So, you'll likely be flown around with one engine more worn and torn than t'other anyway.

[fusion_defusion]

Well, thanks everyone for your replies, all of that makes sense!.

[+TSRA]

Originally Posted by McGoonagall

I have heared somewhere that, in a multi engine acft wear and tear should be close to equal on all the engines?.

Taxi on alternate engines each landing.

Not quite so simple as taxiing on alternate engines as each engine supples power to different hydraulic systems only one of which typically services the normal brakes. You generally don't want to shut down an engine until you are certain you no longer need those hydraulics.

The ATR has a prop brake allowing the engine to continue running with the prop stopped - like another poster already stated.

[easyflyer83]

Single engine taxi (after landing) is SOP at Easyjet.

[Piltdown Man]

For us it's single engine out and single engine back, assuming no good reason to do otherwise.

PM

[McGoonagall]

You generally don't want to shut down an engine until you are certain you no longer need those hydraulics.

Thank you. Suitably informed and educated.

[Peter47]

I've found it very common on US commuter flights, not just taxiing in but also inching forward in the outbound queue at JFK. I should think its makes quite a saving at JFK given the long taxi times.

[spannersatcx]

I once met a 747-400 after it's delivery flt from Boeing, it went straight in the hangar and we changed all 4 engines. The reason being, amongst others, that if you have 4 different engines at different operating hours then you didn't have to do the same task on all 4 engines at the same time further down the road, saving unnecessary downtime. At certains in their life they are removed for overhaul and you don't want to be doing all 4 on one a/c at the same time.

I personally hate single engine taxi, the excessive amounts of power required to manouver on one engine, increases wear, increases the amount of fuel used (I don't believe any is saved because of this) and more importantly he hazards to people on the ground caused by increased jet blast, noise etc.

I saw a 757 the other day trying to do a right turn onto a stand with the right engine only, they must of been at take off thrust trying to get it round the turn.

[Siu Mo To]

If excessive thrust was used during se taxi it is indeed unsafe and inefficient. However, it is just pilot technique. I am doing single engine everyday and 90% of the time idle thrust A320 is sufficient. Sometimes if the ramp area is not flat all I need is less than 1.03 EPR.