When is On-Time, On-Time?

[BOAC4ME]

This is a question for those of you in Ops/Dispach who spend lots of time attributing delays and calling flight's off on time, or obviously delayed.

I just wondered what sort of arrangements different Airlines have with their Ground Handler in terms of what they are permitted to call on time? i.e. what is the period of time after STD they are permitted to call the flight on time when the A/C actually pushes back and do you call this by 'chocks-off', 'A/C flashing', 'Doors shut', 'A/C literally being pushed'....etc, as have seen and heard all of the above being used.

Would be interesting to hear potentially varying comments on this, as this has always seemed a little bit of a 'grey area' to me not being from an OPS background. :ok:

[Dropline]

My personal record for a departure being recorded as "on time" was one that pushed 50 minutes after STD! That was the airlines decision.

It depends on the airline, the ground handler, and what the actual reason for the delay is. Generally up to 5 minutes late and we can usually call it "on time", anything beyond that requires a delay code and time to be recorded to explain why the flight has departed late.

I tend to go by actual pushback time, but you can use the brakes released time (which is what ACARS uses to catch us out when we try and hide a delay!) or the "a/c flashing" time. As you've noticed, there are no hard and fast rules!

I believe the official CAA punctuality statistics count anything departing within 15 minutes of STD as an on time departure.

[TurningFinals]

Where i work it is self manuvering departure.

We call it off blocks once the aircraft starts taxiing. With one airline (because they are the only airline we handle who allow us to do so) we close the doors on time and use delay code 00 (self manuvering departure).

Officially we need to record all delays regardless of how long past the STD, however some captains are more helpful than others, and when you go to agree the delay code with them they say "we'll call it on time.":ok:

[Trash_Hauler]

Generally speaking, I use the old adage that if it is airborne on time then it was on time, ie: I work at MAN.. If one of my aircraft is say parked up on the 50's in T3, those stands are basically at the threshold of 25R, so they tend to have more play with the ATD than say something parked up on T2 or remote as we have a standard 20 minutes taxy time at MAN to "play" with.

[TurningFinals]

which is what ACARS uses to catch us out when we try and hide a delay!

Used to catch us out, however it can be caught out too if a friendly captain releases the parking brake on time. :ok:

[The96er]

Releasing the parking break is fine, however, If the particular airline records the 'Doors closing' time via ACARS too, then you can get the peculiar situation of the aircraft showing to of pushed whilst the doors are still open ! which takes some explaining :ok:

[groundhogbhx]

This is a 'how long is a piece of string' question. Some airlines give an allowance, one of ours calls anything up to 3 minutes late as on time. It can also be very busy with ramp congestion at times:ok:

Generally it is a quick conversation between Captain and Despatcher about what really went wrong. If the Captain is happy that everything possible was being done and it just didn't work then it's on time, if not then you have to start looking for a reason, but anything upto 5 minutes seems to be the norm.

[TheWanderer]

Releasing the parking break is fine, however, If the particular airline records the 'Doors closing' time via ACARS too, then you can get the peculiar situation of the aircraft showing to of pushed whilst the doors are still open ! which takes some explaining http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gifAgain depends on the programming of the ACARS.
Some ACARS use only brakes off, some use the later of brakes off or doors closed.

For us, 5 minutes after STD requireds a delay code, and our ACARS uses the later of doors closed or brake release.

[Gargleblaster]

What's actually interesting is the arrival time, not the departure one !

[Dropline]

Unfortunately no-one looks at the arrival time... contract SLA's and penalties focus on what time the aircraft departs the station and not when it reaches its destination. Handling agents can still pay penalties for delayed departures even the aircraft actually reaches its destination on time or ahead of schedule!

[TurningFinals]

Yes. Even when their aircraft arrives at it's destination on time, if it has left us late and it's our fault, we will still be penalised for it.

[Friendly Dispatcher]

At my station, we have a good working relationship with most of the based crews and work together, anything up to 5 minutes is usually on time. Sometimes with the shorter sectors of maybe only an hour block time, there's less 'covering up' if you like, but a few minutes in a 4-5 hour block or into long haul, becomes less signifcant even though arrival times aren't considered.

Luckily the majority of crews I work with are very down to earth and like groundhogbhx, if things don't work out but the crew are happy things have been done to standard, it's still ontime within reason.

Of course there are the few hardcore captains looking for every minute. I'm not sure most airline ops bods would want inundated with delay codes for flights departing 1 or 2 minutes late.

[PA38-Pilot]

Closing doors 1 minute after Schedule time is considered late, and a delay code must be assigned. And then, another check between Schedule and Actual T/O time (again, even a single minute is considered as a delay)

[Otto Throttle]

Hmmm, let's see..........

If the handling agent delays the flight, it departs on time.

If anyone else delays the flight, it gets shown as late. If in doubt it usually goes down as Crew Eating Meals, Late Crew Boarding Procedures or the catch all 'blame no-one' option of good old DL89.

And then there are the ground handling managers who bury the truth so deep in bull**** and lies that they probably wrote Tony Blair's infamous dodgy dossier on WMDs in Iraq. :}

[chrystall]

we used to have a duty manager cancel the slot on busy monday morning's as we couldnt process the check in queues in time - and then promptly blame ATC as the delay reason when the new slot came through! got rumbled by a capt who contacted BRU to see how many times the station had requested a new slot....

[TurningFinals]

I'd say it's more like if the crew delay the flight, it goes "on time."

If the handling agent delays the flight, the handling agent delays the flight.

Unless ofcourse you have a friendly captain you use the good old DL89 and everyone is happy.

[jerboy]

Closing doors 1 minute after Schedule time is considered late, and a delay code must be assigned. And then, another check between Schedule and Actual T/O time (again, even a single minute is considered as a delay)

Well, pushback would occur a few minutes after that. This is what every airline I've ever dealt with uses as the ATD.

I assume you meant if the ATD is 1 minute later than scheduled (whether you use doors closed/pushback, brake release or whatever), then a delay code should be assigned. Well, technically, yes. However lets think about it; you describe a delay potentially as small as 1 second (ie for a 1235 STD: The difference between 12.35:59 (on time) and 12.36:00 (one minute late)), which I'm sure that even the most hard-assed ops agent wouldn't give a stuff about.

Its all about using your common sense, taking the hit when you've messed up, and not blaming anyone else when it isn't their fault. As mentioned above an agreement is made a lot of the time between ground and flight crews as to whether a flight is 'on-time' given a short delay.

And then, another check between Schedule and Actual T/O time

Really? No airline I've seen has given a 'Scheduled Take-off Time'. Taxi time at both ends is all taken into account in the time between the STD (pushback) and STA (on stand/chocks etc). The variability of taxi times at a large airport would make giving a 'scheduled take off time' nigh on impossible.

good old DL89.

Not so good as it was at my station. Airport management has started requesting the registration/fltno of the aircraft causing the 'blockage', and preventing our aircraft from pushing.

Too many people with not enough to do? Sounds about right eh?

[desertopsguy]

In my corner of the sandpit the reg authority considers anything up to 15mins on time but from a company perspective we are content with schedule to 5mins, anything more than that and the delay is investigated.

All the best.

[no sig]

Everyone has delays sometime, for some reason, they are a simple fact of life in our industry- best avoided of course and there is much satisfaction, for all concerned, when the airplane pushes exactly on time- but delays will happen despite our best efforts. The essential thing about delays is 'trend'. Is a particular station under-performing on a consistent basis? Is a given route a problem, while others do well for on time performance. It is all too easy to chase your tail with delay analysis, the airline has to be realistic in its expectations and this should be reflected in the performance targets in the handling agreement. Delay analysis also requires a careful look at taxi and block times, which can often mask a delay problem.

Passengers today won't blink at a 5 minute delay, after all our watches are rarely all set to exactly the same time, but a turnaround delay of 15 minutes or more needs a detailed explantion.

Arrival delay analysis is important from the airlines perspective of course, study of these can often point to route and block time issues.

[BOAC4ME]

Thanks all, some very interesting points made, particularily with regard to ACARS and the potential 'manipulation' of.

I suppose that the responses pretty much back-up my initial comment that there is very little or no consistancy in relation to this. In my extremely humble opinion there should be a standardised and regulated practice in relation to this issue, as it is (safety aside) the MOST important aim of aviation, particularily for low-costs whose whole existance is based on primarily two things, ancillary revenue and OTP. It shouldnt come down to things like how well someone gets on with a captain, or ways to 'cheat the clock'.

Therefore it should probably be more 'transparent', admittedly some delays are very convoluted with so many parties involved in a turnaround of an aircraft, but if everyone is confident of at the very least a 'true' ATD, then thats a starting point.

At the end of the day if something involves financial reproach then the waters will inevitably be muddied. :ok:

[Opssys]

This post got somewhat out of hand has been divided into:
On Time Tolerance, Airborne Time, Arrival Delays, Delay Manipulation, Delay Analysis (or Lack of it) and Finally.

On Time Tolerance:
Each airline sets its own 'On time Tolerance' in some cases varying it between Short Haul and Long Haul Operation. Whilst there are anomalies, in general the ranges are:

Zero Tolerance - The Aircraft Starts to Move off Stand on Time, otherwise a delay has to be reported.
+2 to +5 Minutes- Used to be the most used set of ranges and suspect still is

+ 5 to + 15 Minutes - Some Long Operators set wider ranges..

Doors Close Time: If the Doors Close at the required time before STD, this lets the Traffic Handling Sections off the 'hook' at any delay assessment, but is otherwise is not used in Operational Messages:
Ranges tend to be:
-2 to -7 Minutes and again the same airline can use different ranges for Short Haul and Long Haul.

Airborne Time:
Whilst Airlines have standard Taxy Times for each Airport and occasionally for individual stands, it is often very difficult for a Ground Handling agency to pinpoint why an individual departure was late getting Airborne especially at busy Airports.
If general Congestion, or some other problem affecting all departures, then fine, but often a single departure will be unlucky and get held up.
ACARS if fitted or traditional Monitoring will tell the Agency Operations Centre of a late Airborne, but finding out exactly why, will take time they don't have.

Arrival Delays:
I have only encountered one Airline that seriously monitors Enroute and Arrival Delays in real time, although I have also encountered several that do post flight Analysis when it is obvious there is a major discrepancy between Departure, Estimated Flight time and Arrival.

If a single Route and/or Period of the Day Affected, a special one off project has proved useful in actually get the Schedule Changed.

Delay Manipulation
For Airside Dispatchers, ‘honesty is the best policy, but the cost can be too high’. Hence the traditional use of the ‘Rubber Watch’, which can also be applied by the Flight Deck Team.

Even ACARS can, as others have stated, be manipulated, although if to be successful requires the cooperation of the Flight Deck and not releasing the parking brake before doors close.

In the new No-Dispatcher systems being introduced by some Major Airlines, where each section involved has to ‘hit its marks’, I suspect there are a variety of new ways being explored to avoid being deemed the cause of delay.

Some level of Delay Manipulation is always going to exist, but it is going to be much more prevalent, when being deemed the Cause of Delay is translated to being Automatically Blamed for the Delay

Delay Analysis (or lack of it)
Delay recording, A Maximum of 4 Delay Reasons is normal, although at Main base this can get much more complicated in apportioning the exact section(s) involved.
Unfortunately these Delay records are often used in playing the Blame Game, rather than reading the Airside Dispatchers Notes, or any Post-Flight review and of course the Airline may penalise the Handling Agency based on the Delay Information sent in the MVT/MVA/OOI Message, without actually finding out the details.


I was once peripherally involved (getting the reporting module of a system to automatically do what was required) in a project to rigorously investigate primary delay causes from Main base and drill down into exactly why they were occurring.
Once the Airside Dispatchers realised their reports were being taken seriously, the quality of information rose significantly. The project actually revealed some very useful results and changes were made in the internal departments involved and some ultimately less useful discussions with the Airport Authority and ATC were held.

Finally:
Using delay codes as the be all and end all of a Blame Game, or Financial Penalty System actually has a negative effect on improving performance. Unfortunately the Blame Game is easy to play (I'll accept this delay, if you take that one, deal done) and the Financial Penalty Systems provide a stick to beat the Agencies with, so these practises tend to become institutionalised in organisations and much to the frustration of the frontline staff as their reports on what/why and how a delay actually came about are ignored. After a while this results in reporting becoming either terse to the point of being useless, or if time allows a rant which relieves the frustration, but can be safely written, because it won't be read!