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A320 single engine taxi out threats

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A320 single engine taxi out threats

Old 21st Aug 2016, 04:48
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TSIO540

"Tell ATC you need 3 minutes at the holding point....."

If you asked ATC for this in Chicago at peak hour because you mistimed the start, it would probably be the last time you ever saw Chicago.
[/QUOTE]

I totally agree.. In Hong Kong you'd be spanked for that too. WRT asking for 3 mins.. I mean a delay owing to SE taxi should not occur with good judgement unless there is a tech fault. With that in mind, don't be a d#%k to ATC, tell them while there is an opportunity to get you out of the way.

One particular operator was taxiing SE in front of us at about 5kts (steady). The controller asked if there was a tech issue. They said "no, it's a new company policy to taxi on one engine!"

The ATC supervisor then advised to "expedite or you can 'company policy' next right into V4 (disused taxiway) and hold until you're ready to taxi faster"
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Old 21st Aug 2016, 07:27
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And that's why we are paid a nice salary: to judge when or when not to...
Don't blame single engine taxi for some pilot's inability to apply common sense. If you know that you will hold up traffic because of single engine taxi, then either don't do it, or increase the thrust on your live engine. Not rocket science.
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Old 21st Aug 2016, 13:25
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I two engine taxi when it makes sense (warm up requirements, short taxi to RWY, required by local procedure, heavy weight at high altitude airport, contaminated taxi ways, etc.)

I single engine taxi from the gate all other times. SE taxi allows me to: call for taxi about 60-90 seconds earlier, saves fuel, helps prevent hot brakes on a quick turn A/C (no brake fans at our company) I also find it easier to taxi SE.

Our checklists are built with SE taxi in mind. After engine start we accomplish the control check and read final items (5 of them - no briefing items). Our fleet has spent a significant amount if time modifying our checklists to prevent our FO's from being heads down during this process.

If I were at an airline which didn't have this SE taxi "culture" built into it, I could see how it could be uncomfortable, for us it is SOP.
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Old 21st Aug 2016, 21:34
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. Tell ATC you need 3 minutes at the holding point....."
Maybe ATC should give more than three minutes notice of position in takeoff sequence?
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Old 22nd Aug 2016, 14:58
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Our checklists are built with SE taxi in mind. After engine start we accomplish the control check
That's a good point here. Did your airline liaise with Airbus to ask for a no objection in performing the FLT CTL check with 1 engine running ?
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Old 22nd Aug 2016, 15:04
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Operated out of ORD yesterday. Started single-engine, came out on A21, right turn on A, left on A17, left on D, started the second engine when joining D, had plenty of time before we got to 22L.

Really not that hard.
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Old 22nd Aug 2016, 15:18
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Makes me laugh.

In our crew room there are these posters from ATC emphasising how important the taxi phase is and how we should avoid distractions; both heads looking outside and agreeing all clearances etc.

So what do we do? Bring in single engine taxi out. Brilliant ! That won't cause any extra distractions will it ?!?!?!

We follow Airbus SOPs and don't do control checks until after both engines are running.


.
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Old 22nd Aug 2016, 16:00
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How did they manage single engine taxi on the DC 9 with a checklist 3x as long and no autostart?
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Old 22nd Aug 2016, 18:58
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So what do we do? Bring in single engine taxi out. Brilliant ! That won't cause any extra distractions will it ?!?!?!
Oh come on.
We do flight control checks et all while taxiing on 2 engines.

Is it REALLY that more distracting for PM to go "Pump off, Bleed on. Ign. Starting eng 2".
No. If you allow yourself enough time (airmanship!) then there is no rush. There is no real extra distraction.

I am sure the next reason we will hear here is "but there might be a fuel leak!". Which usually comes from the guy who disconnects the ground crew before Eng 2 has even starting turning anyway.
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Old 22nd Aug 2016, 20:56
  #30 (permalink)  
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Poppajo

I have not seen single engine taxi in my previous 6 airlines that operate 320/330 in aus/asia/pacific.

Penko,

"Thats not our decision to make".

Its not my decision, i am a simple line pilot. But it is up to flight ops to balance the competing interests of safety and profit. Some do this well, some dont. Bean counters are important but they should never be permitted to be the sole driver of operational policy!

Captainmongo

Great point. Our company does not have SE taxi culture and as such the procedure is rather cumbersome and not very well thought through, IMHO.

Sonicbum,

I suspect the entire SE taxi procedure is done without much support from Airbus.

Ecamsurprise

Many airlines now do the flight control checks stationry before taxi. Both sides.
And I suspect you did not read my second post on the subject, there is a lot more to it than pump/bleed/start. Remember airlines have different procedures and my airline probably does it differently to yours.
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Old 23rd Aug 2016, 11:30
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Just like we only manage errors and not eliminate them we only manage distractions. We don't eliminate them.

Can SE taxi be a distraction for a FO? Sure if he or she hasn't been properly trained, or if the Captain isn't taking into account FO work load or experience or any number of other factors a good Captain should be evaluating to determine whether a two engine taxi is a safer course of action.

I conduct initial operating experience line events and our FO's flying the line for the first time are very comfortable and competent performing duties using SE taxi. Do I call for second engine start on the first leg of IOE earlier than I normally would - of course, by the second or third leg - usually not. Our FO's are conditioned through their simulator training to expect to taxi SE (as are our Captains)

The Captain calls for the control check after the second engine is started. Our procedure does not require the Captain to look inside the cockpit during the control check, the FO monitors the correct displacement on the F/CTL page.

As I stated earlier, I find SE taxi, when appropriate, easier - I'd rather taxi with idle or just above idle power than ride the brakes. Finally SE taxi is encouraged at our airline, it is not mandatory.
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Old 28th Jun 2017, 22:05
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TAXI WITH ONE ENG SHUTDOWN A330

Brake life and fuel savings may govern company policy on permitting aircraft to taxi with one engine shut down.
However, if taxiing out with one engine shutdown, the flight crew should be aware of the following:
It is recommended to retain the use of Engine 1 during taxi to maintain the accumulator pressure of the blue hydraulic system.

If taxi is performed with Engine 2, the flight crew should check the accumulator pressure of the blue hydraulic system.

Slow or tight turns in the direction of the operating engine may not be possible at high Gross Weights.

It is not possible for ground personnel to protect the engine against fire, when the aircraft moves away from the ramp.

The remaining engines should be started with sufficient time for engine warm-up before takeoff

Any faults encountered during, or after, starting the remaining engine may require a return to the gate for maintenance. This could result in an additional departure delay.

Taxi with one engine shut down may require higher thrust than usual. Caution must, therefore, be exercised to avoid excessive jet-blast and the risk of Foreign Object Damage (FOD).

It is recommended that the flight crew use the APU. However, APU bleed should be switched off, in order to avoid ingestion of exhaust gases by the air conditioning system.
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Old 20th Dec 2017, 18:22
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Is there any difference (on arrival) between .
PRK BRK..... on
Y ELEC PUMP .... off
ENG 1 ....... shut down

And (parkbrake on)shut down the eng 1 first then turn off the y elec pump ?
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Old 21st Dec 2017, 08:18
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Hi Finns,

Yes it’s in this specific order to allow the PTU self test. Pay attention next time you switch off both engines you will see the PTU memo on the lower ecam.

EDIT: Can’t find the info in the FCOM to back up what I said above... I might be wrong but I’m sure it’s something to do with the PTU...

Last edited by pineteam; 21st Dec 2017 at 14:51.
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Old 21st Dec 2017, 20:41
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The PTU will run if you have both engines off and the Y pump on.
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Old 22nd Dec 2017, 09:44
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Originally Posted by Finns
Is there any difference (on arrival) between .
PRK BRK..... on
Y ELEC PUMP .... off
ENG 1 ....... shut down

And (parkbrake on)shut down the eng 1 first then turn off the y elec pump ?
No - the yellow pump is a PM task and independent from the engine shut down which is the important bit. Set the parking brake, confirm it's on, and shut down ENG 1. There's no requirement to wait for the pump to go off, although I delay it a second or two to ensure the accumulator is topped off when the park brake is set.
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Old 22nd Dec 2017, 11:22
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Fusty Ferret, I agree, but the standards office here wants this things to be read off the FCOM, as it is a supplementary procedure requiring the pump to be switched off before the engine is.
I hate when I cant use common sense only because thats the way the manual it's written, there are sooo many things like this in operation.

Last edited by MD83FO; 23rd Dec 2017 at 12:22.
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Old 23rd Dec 2017, 10:29
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AFAIK Single engine taxi out is not an approved Airbus SOP on the 320 series ,they have ‘ no technical objection’” which means that airlines can get away with doing it . It is not however an Airbus SOP according to our Airbus guru.
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Old 23rd Dec 2017, 10:55
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I don't work for an airline that uses single engine taxi-out. Just out of curiosity, when does the MEL applicability cease in your operation? It can't be 'when the airplane moves under its own power'...
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Old 23rd Dec 2017, 12:21
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Nil further: the Airbus FCOM suggests otherwise.

KingAir1978: Why not? Dispatch Phase <-aircraft moves-> Flight Phase
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