Can AC turn off engines on the ground / taxi during Earth hour?
Mar 26, 2018, 9:40 am
#16
Join Date: Jun 2003
Posts: 1,934
"This is your captain speaking. We'll be testing out the glide performance of this aircraft during Earth Hour. It may be necessary to restart the engines somewhat sooner than following a full hour of virtue-signalling; we thank you for your understanding."
Last edited by jjclancy; Mar 26, 2018 at 9:40 am Reason: glide typo
Mar 26, 2018, 10:01 am
#17
Join Date: Aug 2010
Location: Why? Why? Zed! / Why? You? Elle! / Gee! Are You!
Programs: Irrelevant
Posts: 3,543
Oh and another thing... Electricity required for lights, air conditionning, IFE screen, USB ports and cockpit systems has to be generated somehow. You can't shut down the engines and APU while taxiing if you want power. Unless you run a really long extension cord from the terminal to the aircraft.
So, no extension cord from the terminal required.
Mar 26, 2018, 12:24 pm
#18
Join Date: Apr 2002
Location: YXE
Posts: 3,050
On jet aircraft such as the A320, the engines power different hydraulic systems, so turning off one of the engines would render one of the hydraulic system un pressurized. There are means to pressurize the system from the other engine, but this is not part of the normal design and would require special operating procedures and brings additional risks to the maintenance requirements of the aircraft. I suspect the additional risks and required maintenance are not worth the effort - otherwise the practice of single-engine taxi-in would be more prevalent.
Mar 26, 2018, 3:21 pm
#19
Join Date: May 2014
Location: YYJ/YYT
Programs: AC 75K (*G), NEXUS
Posts: 652
AC pilots will taxi on one engine whenever possible to save fuel (and reduce emissions, of course). I don't see how replacing an aircraft engine by a tug engine for a single hours would really help reduce emisisons. Moreover, doing so would greatly complicate operations on the ramps and taxiways and would cause potential safety issues.
Mar 28, 2018, 4:15 pm
#20
Join Date: May 2012
Location: YOW
Programs: UA*1K, Marriott Titanium (LTP), Hilton Gold, Hertz PC
Posts: 1,665
Or Gimli Glider, being AC
The descent rate of the plane was about 2,000 feet (600 metres) per minute. They calculated they had about 15 to 20 minutes left before they would be forced to ditch in the ocean.
Mar 29, 2018, 7:31 am
#21
Join Date: Dec 2002
Posts: 8,002
The -400 has a mod that can be purchased that allows for the a/c to taxi on one engine.
Mar 29, 2018, 10:29 am
#22
Join Date: Dec 2007
Location: Toronto - YYZ
Programs: Aeroplan/Hilton Gold/Marriott Bonvoy Titanium/Accor/Hyatt Gold Passport
Posts: 5,899
Departed at 2030 on 3/24. Lights were out // engine(s) was definitely on. IFE was still running - aircraft cannot be in complete darkness.
Mar 29, 2018, 11:29 am
#23
Join Date: Apr 2013
Location: YVR
Programs: Ice Cream Club, AC SE MM, Bonvoy Life Plat
Posts: 2,803
Mar 31, 2018, 11:47 am
#25
Join Date: May 2014
Location: YYJ/YYT
Programs: AC 75K (*G), NEXUS
Posts: 652
Mar 31, 2018, 12:28 pm
#26
Join Date: Aug 2010
Location: Why? Why? Zed! / Why? You? Elle! / Gee! Are You!
Programs: Irrelevant
Posts: 3,543
Not a big deal. Everyone's who flown on an A320 is familiar with the 'barking dog' in the cargo hold -- a hydraulically powered hydraulic pump, or "PTU", that pressurizes the unpressurized hydraulic systems associated with the other engine. This is precisely that system, works very well, and is very practical on the A320 series planes. Single engine taxi-out and in is very common on the A320 series when conditions allow. At places like LAX,etc. where its just a couple minutes of taxi before you're at the runway, they don't bother as the manual requires a period of warm-up, but on longer taxis, where the weights aren't too crazy, its extremely common.
Mar 31, 2018, 12:34 pm
#27
Join Date: Aug 2010
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Posts: 3,543
Many companies having been looking into EGTS for the better part of a decade now. There are still some considerable obstacles to overcome. Weight of the EGTS is one, maintenance is the other. Limited testing has shown that EGTS is beneficial in a very limited and small set of flying cycles. Work on EGTS in general is on-going, we'll get there in another decade or so as better materials are found, weight is reduced, time between maintenance cycles increased and improved reliability.