Can a pilot 'put his foot down'?
Thread Starter
Can a pilot 'put his foot down'?
I know that the scheduled departure and arrival times allow some room for a delayed departure not turning into a delayed arrival; but take the following scenario...
Having been at the airport on time, for whatever reason (spurious or otherwise) the plane is mildly delayed, say by 50 minutes leaving the stand.
The crew announce that 'they will make every effort to make up the time lost". Given that civilian aircraft operate in tightly restricted airspace, how much opportunity do pilots have to go a bit a faster that they were originally intending?
Will ATC accommodate the plane that needs to go that bit faster and needs to overtake a slower aircraft in front? Is it possible for aircraft to fly faster anyway. Presumably there are considerations of fuel loading, tankering and fuel burn?
Or is it simply flannel to make passengers feel better.
My regular experience of a flight that is scheduled for 5hrs and 15mins always leaves about 30- 40 mins late and therefore ususally arrives on time. Any later in departure results in a delayed arrival. I wonder if aircraft ever actually take off at the published time. If they did, they would arrive early. Can that really happen?
Having been at the airport on time, for whatever reason (spurious or otherwise) the plane is mildly delayed, say by 50 minutes leaving the stand.
The crew announce that 'they will make every effort to make up the time lost". Given that civilian aircraft operate in tightly restricted airspace, how much opportunity do pilots have to go a bit a faster that they were originally intending?
Will ATC accommodate the plane that needs to go that bit faster and needs to overtake a slower aircraft in front? Is it possible for aircraft to fly faster anyway. Presumably there are considerations of fuel loading, tankering and fuel burn?
Or is it simply flannel to make passengers feel better.
My regular experience of a flight that is scheduled for 5hrs and 15mins always leaves about 30- 40 mins late and therefore ususally arrives on time. Any later in departure results in a delayed arrival. I wonder if aircraft ever actually take off at the published time. If they did, they would arrive early. Can that really happen?
Last edited by Espada III; 15th Nov 2012 at 16:50.
I wonder if aircraft ever actually take off at the published time.
Join Date: Jul 2002
Location: Bali H'ai
Posts: 427
Likes: 0
Received 0 Likes
on
0 Posts
My recent experience was to leave at 11:04am after a scheduled 10:45am departure and arrive at 3:56pm ahead of a scheduled 4:15pm arrival.
We battled head winds of more than 50 mph for most of the flight yet lopped so much time off the schedule. For the first time in 18 years we did a straight in approach to 27L at Heathrow and I was on a departing Piccadilly Line train at 4:40pm.
Not a bad flight on Malaysian Airlines from Kuala Lumpur.
We battled head winds of more than 50 mph for most of the flight yet lopped so much time off the schedule. For the first time in 18 years we did a straight in approach to 27L at Heathrow and I was on a departing Piccadilly Line train at 4:40pm.
Not a bad flight on Malaysian Airlines from Kuala Lumpur.
Join Date: Sep 2007
Location: Slough, UK
Age: 35
Posts: 281
Likes: 0
Received 0 Likes
on
0 Posts
Pilots can fly a bit faster but usually we're talking 0.01 mach or so. Occasionally the airline may encourage them to fly that bit faster to try and get back on schedule. A slight change in speed over a long sector can make quite a bit of difference. This has to be offset by the increase in fuel burn and the operational impact of having the aircraft delayed.
Thankfully schedules are usually sufficiently padded so that an aircraft will arrive roughly at the scheduled time even if departing a bit later than planned.
Thankfully schedules are usually sufficiently padded so that an aircraft will arrive roughly at the scheduled time even if departing a bit later than planned.
Join Date: Jun 2002
Location: Wor Yerm
Age: 68
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Our schedule normally has a bit of "fat" in it and we are normally planned to fly at an economic speed, cruising level and profile. But when running late, we try for the one, some or all of the following:
1. A quick turnaround and rapid cabin preparation.
2. Full power take-off with minimum flap and maybe an intersection departure.
3. Maximum climb power, high speed climb or high climb rate, depending on the airport and/or direction of departure.
4. Short cuts (on departure, en-route and on arrival).
5. Negotiate the best level for speed (for us FL290, depending on the wind and temperature).
6. The highest sensible cruise speed.
7. A steep, high speed, idle descent or if we have to descend early, one that allows us a little more time at FL290 +/- 4,000'.
8. The most favourable runway at destination.
9. The optimum flap setting for approach to give least time taxiing.
10. Highest sensible taxi in speed.
11. Starting APU on arrival to save waiting for GPU.
So we can turn up the wick if we have to, but it costs. Sometimes as much as 25% more on fuel. Also, when flying close to the limit, you have to be constantly monitoring the aircraft - none of this newspaper reading or sudoku.
1. A quick turnaround and rapid cabin preparation.
2. Full power take-off with minimum flap and maybe an intersection departure.
3. Maximum climb power, high speed climb or high climb rate, depending on the airport and/or direction of departure.
4. Short cuts (on departure, en-route and on arrival).
5. Negotiate the best level for speed (for us FL290, depending on the wind and temperature).
6. The highest sensible cruise speed.
7. A steep, high speed, idle descent or if we have to descend early, one that allows us a little more time at FL290 +/- 4,000'.
8. The most favourable runway at destination.
9. The optimum flap setting for approach to give least time taxiing.
10. Highest sensible taxi in speed.
11. Starting APU on arrival to save waiting for GPU.
So we can turn up the wick if we have to, but it costs. Sometimes as much as 25% more on fuel. Also, when flying close to the limit, you have to be constantly monitoring the aircraft - none of this newspaper reading or sudoku.
Join Date: Jun 2007
Location: Beyond the Blue Horizon
Age: 63
Posts: 1,257
Received 168 Likes
on
103 Posts
Was once upon a time out of Hong Kong on a flight deck of a Virgin 747 behind a BA 747 over western China, both bound LHR, which was slowly caught up, their slow speed was queried. When our pilot asked why BA so slow was told " we are padding some flight time"
When our pilot asked why BA so slow was told "we are padding some flight time"
Join Date: Nov 2007
Location: Polymer Records
Posts: 597
Likes: 0
Received 0 Likes
on
0 Posts
Everything described by PM may save a minute or two. Depending on how low Cost Index is, there may be something to be gained by changing cruise Mach but largely between UK and the Med little more than 5 minutes can be gained by pilot action.
Doesn't mean we won't "do everything we can to get you back as soon as possible".
Doesn't mean we won't "do everything we can to get you back as soon as possible".
Paxing All Over The World
Routing is much of the answer. If they can get a better routing - but then EVERY crew is trying to get a better routing!
I recall a trip back from CDG in the late 80s. We were the last BA out of the day and had been delayed to about 23:00. The Captain did say that he would get us back before the curfew. Because everyone else had gone and the route to LHR was empty, the wheels-to-wheels time was 30 minutes! Smartly into T2 and away! Just remembered, it was a Tristar with that mechanical lifting L1 door.
I recall a trip back from CDG in the late 80s. We were the last BA out of the day and had been delayed to about 23:00. The Captain did say that he would get us back before the curfew. Because everyone else had gone and the route to LHR was empty, the wheels-to-wheels time was 30 minutes! Smartly into T2 and away! Just remembered, it was a Tristar with that mechanical lifting L1 door.
Join Date: Oct 2010
Location: USA
Posts: 76
Likes: 0
Received 0 Likes
on
0 Posts
Unless it's a very very long flight flying faster won't save that much time, but it will burn more fuel.
Time is made up on the ground with quick turn times and short taxi times.
Time is made up on the ground with quick turn times and short taxi times.
Join Date: Feb 2011
Location: UK
Posts: 345
Likes: 0
Received 0 Likes
on
0 Posts
Yes we can make up time by 'putting our foot down.' However, actually flying faster on short (lets say 2-3hrs) sectors will only matter a couple of minutes, if that, between similar aircraft types. If you're doing M0.76 and 777 or so comes whizzing by at M.0845, and he has a little less headwind, you'll see him dissappear in no time. Mostly I would say that tme is won on ground, departure and arrival. We can try and swing things a bit in our favour sometimes but you'll need many parties to cooperate and have some luck.
Last edited by John21UK; 16th Nov 2012 at 05:56.
Only SLF so I have no real idea but it seems that the schedules must have a degree of fat built in so there is some scope for "putting the foot down". Last week we were on an SQ from CDG and by the time we actually took off it was an hour later than the scheduled time of departure (yes, I know that the time refers to push back not getting into the air) but we still made it into SIN ahead of the scheduled arrival time by about 15 mins.
I have no real idea but it seems that the schedules must have a degree of fat built in so there is some scope for "putting the foot down".
If schedules have a buffer built in to them, it's to lessen the need to "put the foot down" following a delayed departure.
Having said that, airlines have to tread a very thin line between being over-generous with scheduled block times (which impacts on utilisation) and trimming them back too much (which affects punctuality stats).
Or is it simply flannel to make passengers feel better.
A change in groundspeed maintained for the groundspeed in miles\minute will result in a change in ETA equal to the change in groundspeed in seconds.
e.g. 480kts gs, increase to 510kts held for 8 minutes will reduce the eta by 30 seconds.
It is a bit approximate, but not a bad guide.
Join Date: Jun 2007
Location: Beyond the Blue Horizon
Age: 63
Posts: 1,257
Received 168 Likes
on
103 Posts
In reply to Dave Reid they landed quite some time behind, I had cleared imigration and was heading for shuttle so well late. Tech problem maybe, but not reported, but as I said a lifetime ago, or so it seems tonight.
It is a bit approximate, but not a bad guide.
Join Date: May 2011
Location: London
Posts: 50
Likes: 0
Received 0 Likes
on
0 Posts
buffer in schedule time
it's also interesting that airlines give themselves different schedule times for the same route at same time of day for example LHR-DUB on BA is 1hr 10, on EI it's 1hr 20. Flybe always add about 1/2 hr extra on their flight times to and from BHD which is why they almost never leave the gate on time but arrival on time figures look impressive!
What are the rules for this? How much buffer are they actually allowed to go up to?
What are the rules for this? How much buffer are they actually allowed to go up to?
Compare block times on a route such as LHR - CDG now with thirty years ago. A 15 min increase is not unusual (mostly longer taxi times, also some extra holding). I couple of years ago I travelled from JFK to Washington DCA with a timetabled block time three times the flight time and double that Eastern were advertising for their LGA - DCA Shuttle in the seventies. Taxi times at JFK around 1700 are rediculous. Mind you, the airline had an impressive on time arrival record.
In regard to flight rather than block time, I'm not a pilot so I'll leave the detailed discussion to the experts, but deviating from optimum cruising speed costs money. I was delayed a couple of hours returning to LHR from HKG a couple of years back after a fault cropped up whilst we were taxiing. The captain said that things had changed and he hoped to shave up to thirty minutes off the flying time. I presume he topped up on fuel before the second push back.
Nothing to do with aviation, but many shipping lines are saving fuel by super slow cruising. Reducing the speed of a container ship by 20% may reduce fuel burn by 50%. I don't know what the trade off is for a typical aircraft - help from experts required - sadly there is not much you can do in a hold. Substituting a prop for a jet will can save you a lot of fuel.
In regard to flight rather than block time, I'm not a pilot so I'll leave the detailed discussion to the experts, but deviating from optimum cruising speed costs money. I was delayed a couple of hours returning to LHR from HKG a couple of years back after a fault cropped up whilst we were taxiing. The captain said that things had changed and he hoped to shave up to thirty minutes off the flying time. I presume he topped up on fuel before the second push back.
Nothing to do with aviation, but many shipping lines are saving fuel by super slow cruising. Reducing the speed of a container ship by 20% may reduce fuel burn by 50%. I don't know what the trade off is for a typical aircraft - help from experts required - sadly there is not much you can do in a hold. Substituting a prop for a jet will can save you a lot of fuel.
Last edited by Peter47; 15th Dec 2012 at 09:47. Reason: Grammar etc
