Flights between Sydney and LA getting slower?

[alwaysanon]

I am fairly certain that it used to be more like ~11 hours one way and ~13 the other on Qantas or United's 747s between Sydney and LA. I just got off a 15 hour flight from LA on a VA 777 and I never remember the flights being that long before.

So my questions are:

• Are my memories on the timings correct?
• Is the 777 slower than the 747? (Would make sense 2 engines instead of 4)
• Is VA going slower to be more fuel efficient or something?
• How does the A380 compare here?

 

[opusman]

The wind probably has something to do with it

 

[MrHyde]

Looking at Flightaware for flights arriving into Sydney today morning, the VA flight was the quickest at 14.5 hours and the QF flight slowest at 15 hours. The delta and united flights were in between those times.

 

[Dr Ralph]

15 hours is the normal time frame for Qantas A380 LAX to SYD.

 

[jb747]

I am fairly certain that it used to be more like ~11 hours one way and ~13 the other on Qantas or United's 747s between Sydney and LA. I just got off a 15 hour flight from LA on a VA 777 and I never remember the flights being that long before.

Are my memories on the timings correct?

No.

Is the 777 slower than the 747? (Would make sense 2 engines instead of 4)

Marginally perhaps. They both initially cruise at about .84-.85.

Is VA going slower to be more fuel efficient or something?

Slightly slower may be more fuel efficient, but it increases time based costs. The ability to fly slower is very marginal anyway. An airliner at cruise altitude can't go much slower or faster.

How does the A380 compare here?

Very slightly slower than the 747. About the same as the 777.

Speed varies throughout a flight. We virtually never maintain the same mach number. It reduces as we burn fuel, but then goes back up when we climb (only to repeat the cycle again.). Generally about .85 winding back to .82.

The number of engines has no effect on the cruise speed...unless you've shut one down.

 

[Quickstatus]

I am fairly certain that it used to be more like ~11 hours one way and ~13 the other on Qantas or United's 747s between Sydney and LA. I just got off a 15 hour flight from LA on a VA 777 and I never remember the flights being that long before.

So my questions are:

• Are my memories on the timings correct?
• Is the 777 slower than the 747? (Would make sense 2 engines instead of 4)
• Is VA going slower to be more fuel efficient or something?
• How does the A380 compare here?

A lot of flights now include have "padded time" added to their schedule to maintain the "on-time" performance. For example SYD-MEL schedule is 1.5 hours but take off to landing is only 1 hour. Some intercontinental flights such as QF1,9,2,10 have a lot of padded time.

 

[Gold60]

not sure myself. but you will know for sure if they ask you to stick your arms out the window and flap FASTER !!

 

[jb747]

A lot of flights now include have "padded time" added to their schedule to maintain the "on-time" performance. For example SYD-MEL schedule is 1.5 hours but take off to landing is only 1 hour. Some intercontinental flights such as QF1,9,2,10 have a lot of padded time.

Firstly the sector time from Sydney to Melbourne is not 1 hour, and I'm curious as to where you get that from. Very occasional flights might manage it, but my average, in aircraft that are about 5% faster than the aircraft doing it these days, is 1:25. Add that 5% and you get a time that is pretty well exactly the current advertised interval.

Flight times are sometimes adjusted to reflect the times that are achieved. Arrivals at Dubai proved to be slower than originally planned, so the times were updated to reflect that. Those times are also used for scheduling crew, so fiddles to make times look good would have the effect of disrupting crew scheduling. There is a statistical basis that's used but I don't recall it.

Some achieved averages vs planned.
Sydney - LA 13:34 vs 13:40
LA - Sydney 14:50 vs 15:00
Melbourne - LA 14:19 vs 14:20
LA - Melbourne 15:33 vs 15:45

The worst deviation in the bunch is in the order of 1%!

 

[BAM1748]

I am fairly certain that it used to be more like ~11 hours one way and ~13 the other on Qantas or United's 747s between Sydney and LA. I just got off a 15 hour flight from LA on a VA 777 and I never remember the flights being that long before.

So my questions are:

• Are my memories on the timings correct?
• Is the 777 slower than the 747? (Would make sense 2 engines instead of 4)
• Is VA going slower to be more fuel efficient or something?
• How does the A380 compare here?

I think you're correct, back in the early 1990s a 747 SP could cover it an hour or more faster than an A380 or 777.

Matt

 

[jb747]

I think you're correct, back in the early 1990s a 747 SP could cover it an hour or more faster than an A380 or 777.

Matt

Which would require a mach .92 cruise!

 

[NoName]

When in F they can take as long as they want as far as I'm concerned. In fact, provided there's plenty of champagne left it'd be ideal if they just stayed in a holding pattern for a couple of hours prior to landing.

 

[jb747]

When in F they can take as long as they want as far as I'm concerned. In fact, provided there's plenty of champagne left it'd be ideal if they just stayed in a holding pattern for a couple of hours prior to landing.

At the end of the flight another, more important, liquid might be in short supply.....

 

[BAM1748]

Which would require a mach .92 cruise!

Out from Sydney 13.5 hours and return 14.5 hours then and now seems to be 14 plus and 15 plus some. I have some old paper schedules from 25 to 30 years ago, but even they seem to vary from version to version so maybe it was season dependant.

I do remember one out of the ordinary trip east bound on a 747 in the mid 1990s where the captain mentioned we had a 'good tail wind' and arrived having been in the air 12 hours. .92 seems to be max speed for a 747 but I did notice in my paper collection of timetables once the SPs were gone the times started increasing. Perhaps it was simply the SPs could carry enough fuel in a lighter aircraft to give it a bit more speed and sustain a higher average. Back in the jurrasic, remember the days of the Captain inviting passengers to have a look in the coughpit while stuck at the gate waiting for a technician to fix something. Plus as a kid TAAs 3 Lockheed Electra's but that's showing my age too much.

At the gate, LHR.

 

[juddles]

Interesting thread - I know the flight rules / maths would disagrre, but I also perceived those flights to be shorter in the past.

Maybe continental drift is getting away on us? Or global warming?

 

[JohnPhelan]

Some people are confusing two different timings - the times obviously vary when comparing 'door close to door open' as opposed to 'wheels up to wheels down'.

BNE-SYD is generally about 65 - 70 mins in the air (wheels up to wheels down on the runway). What I think they call "block" time (door closed to door open) for the same flight is 90 mins. The extra time is basically taxiing.

They are certainly allowing longer taxiing time now than was done 20 years ago - generally seems to be about 15 mins longer.

 

[MrHyde]

Here is some data from my logs. Not a big sample, but seems to be consistent. The variation could just be taxiing time as the airports get more crowded.

MEL - LAX
May 2007 - 14:05 - QF B747
Sep 2012 - 14:15 - QF A380
Feb 2016 - 14:22 - QF A380

LAX - MEL
June 2007 - 15:15 - QF B747
Sep 2012 - 15:47 - QF A380

SYD - LAX
May 2014 - 14:10 - UA B777

LAX - SYD
May 2014 - 14:51 - UA B777
Feb 2016 - 14:18 - QF B747

 

[Quickstatus]

Firstly the sector time from Sydney to Melbourne is not 1 hour, and I'm curious as to where you get that from.

Timetable as published for SYD-MEL is 1.5 hrs but takeoff to landing is 1 hour with the rest for transit time between gate and runway and maybe a small contingency.

 

[jb747]

Some people are confusing two different timings - the times obviously vary when comparing 'door close to door open' as opposed to 'wheels up to wheels down'.

The schedule is door to door. 20 minutes is allowed for taxiing.

Today's flight plans are all 1:10 (plus or minus 2 minutes), for the actual flight time, Sydney-Melbourne.

They are certainly allowing longer taxiing time now than was done 20 years ago - generally seems to be about 15 mins longer.

Years ago (when Ansett existed), the airlines would never print a time than was longer than the opposition. Apparently there was noticeable gain to being the claimed 'faster'. The problem was that both airlines were printing utter rubbish. When the QF 767s appeared on what had been the TAA timesheet, we were stunned to find that it was simply impossible to fly the scheduled times...even though they'd been worked out for slower aircraft. It took some years of complaining before sense started to appear, and the times were converted to what was actually achieved.

 

[jb747]

Out from Sydney 13.5 hours and return 14.5 hours then and now seems to be 14 plus and 15 plus some. I have some old paper schedules from 25 to 30 years ago, but even they seem to vary from version to version so maybe it was season dependant.

I do remember one out of the ordinary trip east bound on a 747 in the mid 1990s where the captain mentioned we had a 'good tail wind' and arrived having been in the air 12 hours. .92 seems to be max speed for a 747 but I did notice in my paper collection of timetables once the SPs were gone the times started increasing. Perhaps it was simply the SPs could carry enough fuel in a lighter aircraft to give it a bit more speed and sustain a higher average.

The max speed of a 747-400 is .92 mach. You might get there with max continuous thrust, but the only time I tried it topped out at .91. The fuel flow was so high that you'd never get anywhere. The maximum useful speed was .87. That would reduce to .85, and then you'd climb...so call the average .86. Over the years that came down a bit, but only by about .01.

The maximum speed allowed these days is .90.

The A380 cruise cost index that we use varies from day to day. Using the minimum CI, we're normally looking at an average of .84. The A380 does climb higher, earlier than the 747, so will have some small effect. I'd expect a 747 would be about 6-10 knots faster over the ground that an A380...so that would give it an advantage of about 15-20 minutes across the pond.

The SP was a bit slower than the full sized aircraft.

 

[24601]

Interesting thread - I know the flight rules / maths would disagrre, but I also perceived those flights to be shorter in the past.

Maybe continental drift is getting away on us? Or global warming?

Maybe as economy classes get worse the flights seem longer. It is strange because as we get older, time usually seems to pass more quickly. On familiar journeys visual cues we get from landmarks help make trips seem faster. But in the air we don't really get these. Wonder if there is anything in that.

I have no idea how long my longest SYD-LAX was in hours, but it was in Y on a United 747. It seemed endless. Time definitely passes more quickly up the front.