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View Full Version : Single engine taxi vs no engine taxi?


Screwballs
16th Apr 2008, 10:03
I flew on a well known airline recently and sat at the over wing exits. I have over 1500 hours on the type flown and more on other types. Without doubt, we taxied onto the apron and at a decent speed, shut down both engines. At least 200 meters from the turn on. We then turned onto stand and came to a halt free-wheeling so to speak. It has happened on the airline before but usually just as we come onto the stand, not 200 meters from the turn onto stand.

My question: Is it safe? Is it legal? Is it now SOP in some airlines?

Screwballs

Ps. to assist in the technical side the aircraft type was a 737 NG.

mini-jumbo
16th Apr 2008, 10:27
In my opinion, simple common-sense would dictate that this is not very sensible. For one, a last minute change of stand could make that very embarrassing. Or, being asked to stop by ATC for what ever reason.

Nightrider
16th Apr 2008, 11:23
As mini-jumbo already said, not very sensible. :ugh: However, there is training going on or, as in some case, training to commence, for a one-engine approach to apron and gate. :eek: This is also in my company a discussed issue and there are cost saving reasons behind it.
Saving 2€ on fuel for each arrival (just a guess) on a fleet of more than 100 aircraft following this at least 4 times a day gives a saving of 365000€ a year.....:cool:
In case of lo-co airlines, having the #1 dead arriving at the gate allows for immediate deployment of the airstairs (B737NG) and saves about 18,5 seconds on turn-around..... :E
MOL will love it....

mini-jumbo
16th Apr 2008, 11:44
One engine taxiing when there is a long taxi, I can see the argument for fuel saving, although as I don't fly a 2 engined a/c I'm not sure on the handling characteristics of single engine taxiing.

And yes, MOL will love the time saved on turnarounds.

Gary Lager
16th Apr 2008, 12:04
Single-eng taxi in is SOP in my airline - assuming adequate engine cool-down time, no adverse taxiway/apron characteristics etc etc. Absolutely no problem with handling, as long as you anticipate any taxiway gradient. Saves in the region of $millions if applied over the whole (large) fleet.

Screwballs, I would be very careful of using the words without doubt in this industry; no matter how sure we are of something, we are still prone to error.

Down the back of a 737NG is not the best position to judge things.

Why not write to airline concerned, and ask for an explanation of their policy in this regard? Or file a quick CHIRP report, which can be followed up with the airline whilst preserving your anonymity.

Old Fella
16th Apr 2008, 12:14
Screwballs, I don't like to pour cold water on a good yarn, however I cannot believe that your "well known airline", or any other responsible airline would countenance an event as described by you. I note you have NO DOUBT that it happened. If you are ABSOLUTELY SURE the aircraft "free wheeled" for 200 metres you should, at the very least, change the airline you fly with to one with a responsible approach to the job. :ok:

Screwballs
16th Apr 2008, 15:04
I am well aware of the usual "down the back" comments but I would bet my salary on it. I pax on the same airline, same seat about once a week. I know what it is like. So assume just for now, it is happening.

As it stands, the reason I posted on pprune was to see what people thought before I file a CHIRP report and contact the company. The reason I asked the question was because, when I actually thought about it, what is unsafe about it or illegal about it?

Legally; I couldn't think of any document that specifically prohibits coasting onto stand. But then by the same argument, you can't say it's allowed just because it isn't specifically dis-allowed.

Safety-wise; you still have electric hydraulic pumps, and if APU goes kaput then at least 6 efforts from the accumulator to come to a safe halt.

So to summarise, can you tell me if it is illegal to taxi without power, and why it would be unsafe? I'm just looking for opinions - I know what this place is like hence the anonymity of the airline.

Thanks for the contributions so far,

Screwballs.

Spitoon
16th Apr 2008, 18:14
Don't know where you are but the UK ANO says:

An aircraft shall be deemed to be in flight:
(a) in the case of a piloted flying machine, from the moment when, after the embarkation of its crew for the purpose of taking off, it first moves under its own power until the moment when it next comes to rest after landing.

It doesn't seem to matter whether the engines are running when the aircraft comes to rest.:)

A-3TWENTY
16th Apr 2008, 19:38
No meat , no barbecue...

In the near future the airline financial genius will start to ask us to shut one engine down for descent.

Since I have never a seen a company get out of business because of the pilots , better to think about shutting some administration benefits down.