B737 taxi with one eng.
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B737 taxi with one eng.
Hello everybody! I want to know,please, if there is any company which has a special procedure for taxing a B737 with one engine shut off for fuel economy! If yes,what is that procedure? Do you think it really make a fuel saveing? Any difference between clasic and NG?
Thanks!
Thanks!
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after LD and after 2 min cooling you can cut 1 eng. restrictions apply: sharp turns, slope, contaminated taxi ways etc
and we are *supposed* to start the APU and take it on bus. isn't it strange how you can fly with one eng, but need the apu for taxi!?
and we are *supposed* to start the APU and take it on bus. isn't it strange how you can fly with one eng, but need the apu for taxi!?
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My company started this a few months ago. We wait 3 minutes after landing to allow engine to cool and make sure the APU is on the busses. If you're light and have a long taxi in (eg 18R @ AMS) it probably saves fuel and riding the brakes but if you're heavy its hard to see any saving as you have to spool up the remaining engine quite a bit and the fuel flow is doulble the idle value. It's also handy on some bridges as it prevents the left engine from ingesting debris (on a 500 the #1 gets very close to the jetty as you park)
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isn't it strange how you can fly with one eng, but need the apu for taxi!?
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Single engine taxi-out is not done and no procedure exists in my company. Single engine taxi-in on the other hand is allowed if the plane is under a certain max weight (300/500 46t, 700 50t, 800 57t) and after a cooling period of three minutes. The apu is started as part of the normal taxi-in procedure anyway, besides one engine supplies both electric hydraulic pumps with power, each engine powers one brake system and the brake accumulator allows several brake applications if all hydraulic power is lost. All in all not really critical and has been done for the last 10 years.
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What's strange is that statement! Are you really allowed to fly a twin on one engine with APU shut down?
isn't it strange how you can fly with one eng, but need the apu for taxi!?
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Hang on. The single engine flight vs single engine taxi is a completely different discussion. I'm gonna have a rough stab in the dark here but single engine taxi would be a planned operation (hence redundancy required) but single engine flight in revenue service is a completely different ball game.
Single engine taxi in a 737 with the way the hydraulics are set up is a no brainer. Loose the engine and you have the APU supplying both hydraulic systems. Loose the APU and both are still supplied.
Single engine taxi in at AMS 18R always saved me 100kg....Its worth while.
Single engine taxi in a 737 with the way the hydraulics are set up is a no brainer. Loose the engine and you have the APU supplying both hydraulic systems. Loose the APU and both are still supplied.
Single engine taxi in at AMS 18R always saved me 100kg....Its worth while.
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Thank you all,guys! But seems to me that very few of us is using this procedure.All of you that use this,do you have a checklist for that? Is it a special procedure in your company SOP? I know is not really a big thing but it need a procedure,doesn t it?
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No, pure airmanship is enough. No special procedure for us and we do use it, at least for taxi in. Taxi-out might be another thing as you have to assure a sufficient warm-up time before you can set take-off power.
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Single engine taxi in at AMS 18R always saved me 100kg....Its worth while.
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Actually, the issue of landing gear loads with engine out taxi has been examined and it is a non-event. The incremental load difference for engine out taxi is very small and the specs for undercarriage loading are very robust. there are many other events that put far higher stresses on undercarriage components.
The whole issue of landing gear loads for engine out taxi is an urban legend promulgated by "concerns" not based in fact.
Lots of operators do single engine taxi in and out. Yes, it requires thought, good SOP's and training. Like any other tool in a pilots tool box it has a time and place to be used. It also saves significant dollars that at the end of the day contribute to the financial health of the airline - something we all need to ensure we have a job.
The whole issue of landing gear loads for engine out taxi is an urban legend promulgated by "concerns" not based in fact.
Lots of operators do single engine taxi in and out. Yes, it requires thought, good SOP's and training. Like any other tool in a pilots tool box it has a time and place to be used. It also saves significant dollars that at the end of the day contribute to the financial health of the airline - something we all need to ensure we have a job.
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NG-fleet only, allow 2 min. for cooldown, APU up and running and on bus, shut down #2 (make sure there's no 90+ degree turns 
)
Taxi out both donks runnining (even on AMS) APU on captains discression.
)Taxi out both donks runnining (even on AMS) APU on captains discression.
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Which engine to shutdown is a function of hydraulic and electrical system architecture. Manufacturer's provide guidance on this in the FCOM. Some aircraft are sophisticated enough, or have good SOP's, that this is a moot point and you can shut down either engine and then the choice should be driven on taxi turning direction.
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the choice should be driven on taxi turning direction.
At this point I gave up the one-engine stuff.
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- and BA's favourite trick at LGW was to change your stand as you came in, and then not have it 'ready' so you had to stop before entry........................ At this point I gave up the one-engine stuff
At this point I gave up the one-engine stuff
Well said Nigel. but then no difference in MAN either these days!
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It also saves significant dollars that at the end of the day contribute to the financial health of the airline - something we all need to ensure we have a job.
Amazing what operational measures can be taken to contribute to the financial health of the airline - something we all need to ensure we have a job...
