Krisz

It was a very interesting take off. Pushback was on time, nothing major delay, LHR looked normal not crazy busy so I was very surprised to be line up at A8 for a 27R departure.
For those who are not a pilot or doesn’t have a LHR airport chart in front of them, it was a take off half way down the run way. I know the runways are long and I bet an A320 could take off shorter distances than that, however I’ve never seen or experienced such a shortened take off run.

Anyone knows how this can happen? I thought pilots motto is no runway behind. Is it BA ops or LHR tower asks to take off half way? Or just the captain had enough taxing. 😏

BTW we landed early in MAN.

KARFA

Had A8 once before. Depends on where the takeoff performance is calculated from but it’s entirely fine - it won’t be carrying much fuel for a short sector like that. you will be familiar with BA planes taking off from shorter runways of course

EDIT: 2414m of runway from A8 btw

corporate-wage-slave

I remember you querying this at the time. And someone from the Tower essentially said "yes, if we see a nice gap and a small aircraft trundling up to the top we invite them to hop over to the runway and get going". They probably used fancier language than that though.

Krisz

Yes you are right that our common favourite airport has a shorter runway than that plus sometime BA doesn’t use the full length there as well, also I read somewhere that the A320 take off performance can be better than the A319 depending the actual engine performance rating. So yes it was perfectly safe and doable.

I was just interested who is deciding lets do this? I think CWS gave the answer above, as a tower request/offer. (I’m guessing the pilots can refuse it? No idea.)

Anyway it was great not to waste time and fuel to taxing around LHR.

navylad

yes, flight crew can always decline an offer such as that and request to continue to taxi to the threshold.

Scott Pilgrim

An intersection departure, not unusual and allows increased flexibility and utilisation.

Probably, certainly used to be, most frequent on 09R as it allowed the most opportunity. Scenario... two A320 south bounds at the threshold waiting to depart that require a two minute departure separation. Third A320, northbound, taxiing to the hold gets asked if could accept an intersection departure from (insert appropriate intersection here) and says yes.

First southbound cleared for take off from threshold, as it passes the appropriate intersection northbound lined up and duly cleared for takeoff.

As northbound departing second southbound is lining up at threshold and ready to go as soon as northbound airborne.

Max runway utilisation.

Based pilots of appropriate types always used to work out the figures for the most used intersections just in case they got lucky!

As ever, lots of rules around when you can and cannot do multiple lineups.

navylad

presumable this way of operating has decreased with the algorithm based dispatch?

Scott Pilgrim

Probably needs Heathrow Tower to answer that specifically.

ahmetdouas

2414 meters? That’s miles and miles for an A320, you probably took off in about half that distance without even using max power given the weight on such a short sector !

noFODplease

And hopefully some info on how the algorithm based despatch works too if he wouldn't mind

Naz1

I've often heard crew tell the controller during initial taxi clearance that they are able to accept a certain (or range) of intersections for departure at which point the ground controller will pass it on to the departure controller who will see if they need or want to use an intersection.

South London Bon Viveur

Presumably onus is on flight crew to request intersection departure or does ATC offer it pro-actively?

Lynyrd

ATC tell you which intersection to use. They will have the experience not to offer it to a jumbo on a JNB but an Airbus can take A8 no problem, it may just have a slightly reduced FLEX temp.


The BA Route Information Manual for LHR states-

A32N
Intersection Planning
• FLEX should be maximised whenever possible when deciding upon the planned
intersection for departure.
• BAW Airbus and LHR ATC have agreed default intersection plan to use
A3/N2E/N11/A13. ATC will give a minimum notice of: 1 min for default
intersection, 3 mins for change of intersection or 5 mins if OET.
• ATC may offer a reduced notice, shorter intersection in the following cases:
– When departing North bound
– First wave departures
– With a tight CTOT
– T3 departures using 09R
• In order to gain this tactical advantage, it may be prudent to plan on a shorter
intersection for departure whilst still attempting to maximise FLEX.
• To assist ATC in keeping R/T to a minimum, when requesting the ACARS PDC,
consider adding a line in the free text section for the planned intersection e.g.
‘Able NB8’.

So with MAN going out on an UMLAT that meets the northbound departure criteria.

KARFA

Reminds me of this recent tweet

Twitter

alvinlwh

If there was a 380 in front of you in the queue, it will be a 3m before the "little" 320 is allowed to start its roll whereas "jumping the queue" cuts the wait down to zero. Also time will be saved for taxing and waiting (idle waste fuel).