How can a LHR flight be 14 hours late departing?
 

Looking at BA 251 LHR-SCL is showing as departed 14 Hrs late.I am just a simple soul but cannot understand why a flight emanating from a home base could be subject to such a long delay when spare aircraft/crew should be available outside the peak season.
I am due to fly this route in February so hence the enquiry.
Thanks in advance to those who can explain.

I guess the 22.00hrs departure doesn't leave much wriggle room / spare capacity when it occurs late

Low season is also the season when aircrafts have most heavy maintenance; plus there might be some spare but not enough to cover a ritation of the length of LHR-SCL flight.

additionally, this route is served by 787s. Due to the ongoing struggle of Rolls Royce to overcome the limits of the law of thermodynamics, there are at least 2 787s without engines: this makes it very hard to sub one that has thrown a wobbly.

finally, it’s a late flight. Anything more than 2hrs and it’s night time ban.

If you want chapter and verse - which I would not advise - I would look up "Trent turbine blades on 787s" on this forum or elsewhere. There simply are not spare 787s lolling around the back of Heathrow waiting for someone to whistle for them. And crew don't grow on trees either. I don't know the exact cause for this delay but I would suspect a technical fault, perhaps combined with the complex crew hours on that route, led to this long delay, and there wasn't the possibility of moving to another aircraft. On this sector it can - at the moment - only be a 787 service, unless they split it up into several jumps (which again poses working hour issues). So shoving in a spare 747 unfortunately wouldn't work either. But it would be nice to see BA's 747s back in SCL of course. Then there is the issue of night flights at Heathrow and getting clearance for arrival in SCL.

Past performance is no guide to future deliverables.

You have been given possible reasons for a long delay. Sometimes poo happens, but I would not extrapolate from a single incident to a trip you are taking in several weeks.

Probably happens more than we know. I've had 24H delay (AY HEL-BKK Airbus 350) which is a pain but great for a bit of compensation x 4 pax !!

Speaking in generalities It takes time to prep a replacement aircraft - tug replacement plane from the hanger assuming one of the right type is available) takes time, then unload and reload the luggage and catering, fuel it up etc etc - if one goes tech and then run the risk of the night flight restrictions . Could also be landing restrictions at the destination airport to factor in as well.

rather then instigate a rolling delay perhaps BA just cancelled it at a relatively early hour so passengers could get to hotels at a reasonable hour as well?

Oooh good point, I imagine any backpacker types on the flight would have been cuffed with 600EUR comp and a loss of a half day

not just backpackers I’d be rather happy too.

I will just add on that, we also put our hands up for an offload on the return due to over booked AY flight. Got put onto the TG flight 14 hours later & EUR300 each, so actually I was in flight profit on this trip !

It’s changing to a triple in February as I’m booked on it!

I once had an easyJet overnight delay at Gatwick. Problem was with the aircraft, but by the time the aircraft was fixed the crew had reached the limit of their hours...apparently there wasn't a backup crew left.

Indeed, my son was extremely pleased with the 9 hour delay from ABZ to ALC on yesterday's FR8006. Watched Netflix all day while he and his girlfriend worked out what to do with the 400 euros apiece

There were a few 787 issues yesterday, some inbound (KIX), and some outbound (MCT/SCL/ISB). Unfortunately the 787 fleet is very busy and there simply are loads of aircraft parked up ready to go. During the day there are probably enough crew around to be able to completely re-crew an aircraft, but that's one of the last flights to leave, so there would typically only be enough crew on standby to replace the occasional person to not turn up. The long stage lengths mean crew operating hours are very tight so can't just spend hours in the airport waiting to go.

Swapping for another type (e.g. 777 or 747) just isn't possible as the (787) flight crew already in SCL wouldn't be able to take the aircraft home, and there will also probably a mismatch of the number of cabin crew as the 787s are smaller than the 777 or 747.

Also, as others have pointed out, the SCL leaves very late, so there are numerous issues with finding a new aircraft and crew at late notice. Remember that the last thing BA wants is 200 or so people delayed overnight, plus the same coming home, and a very delayed aircraft then missing from another day's trips. The costs are staggering once you add compensation and hotels etc - BA want on-time departures more than you do!

What dates is it a Triple? 772 or 773?

Are you sure? I've checked the February calendar and I can't see it? Which date is this?