YYZ-SAN via a fuel burn and Lake Superior
Jan 1, 2013, 8:49 pm
#1
Original Poster
Join Date: Apr 2000
Location: Toronto, Ontario, Canada
Posts: 3,665
YYZ-SAN via a fuel burn and Lake Superior
On Dec 31 AC 777 (Toronto-San Diego, A319)- taxied to the takeoff runway and sat with engines running for over 30 minutes. Flight deck announced we were too heavy and was burning excess fuel. How is this problem determined and how can the weight be known with no scale? Also, I followed the IFE map. We headed NNW to Sault Ste Marie then west to Montana before turning southwest. Seems like a very strange route - was the jetstream running in reverse? We were only a half an hour late for all the strangeness.
Jan 1, 2013, 8:59 pm
#2
Join Date: Dec 2008
Location: PHL, NYC, DC
Posts: 9,708
pilots have to calculate how much fuel they are carrying...... i believe the volume is converted into weight (by a formula).
as for routing, anything can happen. Sault Ste Marie is not that far off Toronto (by flight).
as for routing, anything can happen. Sault Ste Marie is not that far off Toronto (by flight).
Jan 1, 2013, 10:25 pm
#3
Join Date: Nov 2012
Location: YWG
Posts: 2,272
I believe that Jet A weighs something like ~6.8 lbs/gallon (I really liked playing FSX when I had a Windows machine, and FSX worked it out to something like that). I also believe that they have standard weights for passengers (assume each passenger is X pounds, with Y pounds of baggage).
As for routing, aren't you trying to avoid the jet stream when flying westbound? The jet stream flows west to easy, so when flying to SAN, the jet stream would give you a headwind and slow you down. That might explain the strange route.
As for routing, aren't you trying to avoid the jet stream when flying westbound? The jet stream flows west to easy, so when flying to SAN, the jet stream would give you a headwind and slow you down. That might explain the strange route.
Jan 1, 2013, 10:40 pm
#4
Join Date: Dec 2008
Location: PHL, NYC, DC
Posts: 9,708
I believe that Jet A weighs something like ~6.8 lbs/gallon (I really liked playing FSX when I had a Windows machine, and FSX worked it out to something like that). I also believe that they have standard weights for passengers (assume each passenger is X pounds, with Y pounds of baggage).
As for routing, aren't you trying to avoid the jet stream when flying westbound? The jet stream flows west to easy, so when flying to SAN, the jet stream would give you a headwind and slow you down. That might explain the strange route.
As for routing, aren't you trying to avoid the jet stream when flying westbound? The jet stream flows west to easy, so when flying to SAN, the jet stream would give you a headwind and slow you down. That might explain the strange route.
Jan 1, 2013, 10:43 pm
#5
Join Date: May 2005
Location: Winnipeg
Posts: 205
lots of the westbound transcons (like BOS-SEA, JFK-LAX) have been operating routings that are more northern over the past week... to avoid strong jet streams. Today, the extremely powerful jet stream seems to be located just south of Toronto, where eastbound aircraft are cruising as high as 800mph and westbound at about half that speed, or less.
Jan 1, 2013, 10:47 pm
#6
Join Date: Nov 2012
Location: YWG
Posts: 2,272
I am contemplating getting X-Plane, however.
Jan 2, 2013, 12:09 am
#7
Join Date: Apr 2005
Location: Toronto
Programs: AC SE MM, Marriott Lifetime Titanium, Hyatt Globalist
Posts: 2,101
Jan 2, 2013, 1:03 am
#8
Join Date: Sep 2012
Location: Australia and Canada
Programs: Qantas FF Plat; Virgin Aust Plat;
Posts: 799
On Dec 31 AC 777 (Toronto-San Diego, A319)- taxied to the takeoff runway and sat with engines running for over 30 minutes. Flight deck announced we were too heavy and was burning excess fuel. How is this problem determined and how can the weight be known with no scale? Also, I followed the IFE map. We headed NNW to Sault Ste Marie then west to Montana before turning southwest. Seems like a very strange route - was the jetstream running in reverse? We were only a half an hour late for all the strangeness.
Fuel load (volume to mass), anticipated fuel burn and mass of aircraft (metal, pax, their baggage and freight etc) I believe are part of that last minute flurry of paperwork you see passing between the ground crew and flight deck.
The weight can change around with last minute heavy-ish freight being loaded or unloaded, or maybe a bunch of pax and their baggage not making the flight or being boarded at the last minute (missed another connection).
Seems in the OP's case too much fuel was taken on with the final overall weight configuration, so rather than pumping it out (maybe the gate needed to be freed up) they burned it off.
Your fuel surcharges at work.
Jan 2, 2013, 7:17 am
#9
Join Date: Jan 2013
Posts: 144
On Dec 31 AC 777 (Toronto-San Diego, A319)- taxied to the takeoff runway and sat with engines running for over 30 minutes. Flight deck announced we were too heavy and was burning excess fuel. How is this problem determined and how can the weight be known with no scale? Also, I followed the IFE map. We headed NNW to Sault Ste Marie then west to Montana before turning southwest. Seems like a very strange route - was the jetstream running in reverse? We were only a half an hour late for all the strangeness.
Normally, an Airbus A319 will burn 200kgs of fuel to taxi from the terminal to the end of the runway. If de-icing is anticipated, Air Canada dispatch will tell the fuel company to board extra fuel to accommodate the delays in the de-icing pad. I have seen upwards of an extra 800 kgs of fuel added to account for the de-icing delays. In Toronto, as at most stations, de-icing is done with the engines running. If you sit in the de-icing bay for an extended period you are burning fuel. Sometimes de-icing is not required, yet extra fuel has been boarded for it. On most flights it is not a problem. The aircraft are still well below their maximum take-off weight, therefore the extra fuel just gets carried to destination. However, on your flight (YYZ-SAN) I would guess that the aircraft was very close to it's maximum take-off weight without the extra fuel. Because the extra fuel had not been used for de-icing all (or a portion) of it had to be burned off prior to take-off.
There could be other reasons, but I would guess that the one I have mentioned is the most likely.
Also, I had a look at the jet stream on December 31st. It was in fact, running pretty much straight from southern California to southern Ontario. Therefore it made sense for the flight to go west to get out of the winds and then southwest to San Diego.
Jan 2, 2013, 8:38 am
#10
Join Date: Jul 2003
Location: Salish Sea
Programs: DL,AC,HH,PC
Posts: 8,974
The smaller the airplane the tighter the parameters. CRJs have been known to return to the gate to unload baggage and very occasionally, passengers.
Don't ask me how I know
.
Jan 2, 2013, 4:36 pm
#11
Original Poster
Join Date: Apr 2000
Location: Toronto, Ontario, Canada
Posts: 3,665
I looked at a map of the current jetstream flow. Indeed there is a countercurrent flow (E-W) that runs roughly from Minneapolis to LA, an eddy current to the main one that is running from Mexico City to Chicago and Toronto. http://www.intellicast.com/National/Wind/JetStream.aspx
Last edited by B1; Jan 2, 2013 at 4:44 pm
Jan 2, 2013, 4:57 pm
#13
Join Date: Aug 2012
Programs: AC E35K, NEXUS
Posts: 4,368
That explains my last YYZ-SFO. I thought they were lost!
Jan 2, 2013, 5:20 pm
#14
Join Date: Aug 2012
Posts: 323
There could be a few reasons why it was was necessary to sit at the end of the runway to burn off fuel, but I will give you one possible scenario.
Normally, an Airbus A319 will burn 200kgs of fuel to taxi from the terminal to the end of the runway. If de-icing is anticipated, Air Canada dispatch will tell the fuel company to board extra fuel to accommodate the delays in the de-icing pad. I have seen upwards of an extra 800 kgs of fuel added to account for the de-icing delays. In Toronto, as at most stations, de-icing is done with the engines running. If you sit in the de-icing bay for an extended period you are burning fuel. Sometimes de-icing is not required, yet extra fuel has been boarded for it. On most flights it is not a problem. The aircraft are still well below their maximum take-off weight, therefore the extra fuel just gets carried to destination. However, on your flight (YYZ-SAN) I would guess that the aircraft was very close to it's maximum take-off weight without the extra fuel. Because the extra fuel had not been used for de-icing all (or a portion) of it had to be burned off prior to take-off.
There could be other reasons, but I would guess that the one I have mentioned is the most likely.
Also, I had a look at the jet stream on December 31st. It was in fact, running pretty much straight from southern California to southern Ontario. Therefore it made sense for the flight to go west to get out of the winds and then southwest to San Diego.
Normally, an Airbus A319 will burn 200kgs of fuel to taxi from the terminal to the end of the runway. If de-icing is anticipated, Air Canada dispatch will tell the fuel company to board extra fuel to accommodate the delays in the de-icing pad. I have seen upwards of an extra 800 kgs of fuel added to account for the de-icing delays. In Toronto, as at most stations, de-icing is done with the engines running. If you sit in the de-icing bay for an extended period you are burning fuel. Sometimes de-icing is not required, yet extra fuel has been boarded for it. On most flights it is not a problem. The aircraft are still well below their maximum take-off weight, therefore the extra fuel just gets carried to destination. However, on your flight (YYZ-SAN) I would guess that the aircraft was very close to it's maximum take-off weight without the extra fuel. Because the extra fuel had not been used for de-icing all (or a portion) of it had to be burned off prior to take-off.
There could be other reasons, but I would guess that the one I have mentioned is the most likely.
Also, I had a look at the jet stream on December 31st. It was in fact, running pretty much straight from southern California to southern Ontario. Therefore it made sense for the flight to go west to get out of the winds and then southwest to San Diego.