Yet Another Cycling Forum

Off Topic => The Pub => Topic started by: meddyg on 18 June, 2023, 10:15:04 am

Title: Interesting flightpath (adjustment)
Post by: meddyg on 18 June, 2023, 10:15:04 am
I do waste a little more time than I need on Flightradar 24 !
This was Friday evening staying with friends near Llandysul.
- yes, just across the valley from Basil !
You can see 'em all heading for the Atlantic in daylight.
But this must've been a disappointment for folks bound for Washington !


(https://images2.imgbox.com/19/d0/nVsgL7Uk_o.jpeg) (https://imgbox.com/nVsgL7Uk) (https://images2.imgbox.com/08/6a/mOKxZtmR_o.jpeg) (https://imgbox.com/mOKxZtmR) (https://images2.imgbox.com/81/86/PN6M9zbD_o.jpeg) (https://imgbox.com/PN6M9zbD)

(I think we have a specific aerobatics forum, but I can't find it today).
Title: Re: Interesting flightpath (adjustment)
Post by: quixoticgeek on 18 June, 2023, 10:18:38 am

Interesting why they would do that.

For a full on emergency, Shannon or Dublin would be closer diversions.

J
Title: Re: Interesting flightpath (adjustment)
Post by: perpetual dan on 18 June, 2023, 10:23:33 am
I’ve had a flight turn back half way across the North Sea before (after a lot of waiting for snowploughs and de-icer). The thing that failed had redundancy, so there wasn’t an emergency, but you wouldn’t take off again without a working spare. It was easier to get the module they needed to replace at their base than it was at Gatwick. So back we went.
Title: Re: Interesting flightpath (adjustment)
Post by: meddyg on 18 June, 2023, 11:43:58 am
Next morning
posted on https://aviationa2z.com/index.php/2023/06/17/virgin-atlantic-london-washington-flight-declares-an-emergency-exclusive/
 (https://aviationa2z.com/index.php/2023/06/17/virgin-atlantic-london-washington-flight-declares-an-emergency-exclusive/)
FIRST UPDATE: The flight landed safely at LHR, and passengers are getting disembarked. We will see whether VS will arrange an alternative aircraft or will cancel the flight.

SECOND UPDATE: According to some reports, the plane diverted due to high engine vibration parameters. While some stated that there is a storm ahead of the flight led to this high vibration and, ultimately, the diversion back to London.
Title: Re: Interesting flightpath (adjustment)
Post by: Basil on 18 June, 2023, 11:49:41 am
with friends near Llandysul.
- yes, just across the valley from Basil !

*waves*
Title: Re: Interesting flightpath (adjustment)
Post by: Canardly on 18 June, 2023, 12:02:02 pm
I have often wondered when perusing FR24 why a declared 7700 diverts to an airport miles away from the neared available major airport. Is this because the faulty system has a back up?
Title: Re: Interesting flightpath (adjustment)
Post by: Kim on 18 June, 2023, 12:15:53 pm
As perpetual dan suggests, at least some of the time the problem isn't something that's deteriorating (and would perhaps be considered acceptable while flying over land with full radar coverage, but not the middle of the ocean), and it makes more sense to continue to where it can be repaired, rather than leaving the plane at some random unequipped airport where it can't safely take off again.

Or of course continuing to an airport with no sketchy weather/terrain, a nice big runway and plenty of emergency services might make sense...
Title: Re: Interesting flightpath (adjustment)
Post by: PaulF on 18 June, 2023, 12:28:34 pm
I have often wondered when perusing FR24 why a declared 7700 diverts to an airport miles away from the neared available major airport. Is this because the faulty system has a back up?

An abundance of caution perhaps? If it’s non-critical it’s probably best to get to a home base where they have an engineer, spare parts and support for the passengers.
Title: Re: Interesting flightpath (adjustment)
Post by: Jasmine on 18 June, 2023, 03:16:00 pm
Yes, going back to a primary base seems a smart move. I've been on a trans-Atlantic flight that was turned around for an electrical fault (we got to sit in the dark with a strong burning smell). We landed in Shannon, where there was no engineer who could fix it. The engineer had to be flown in from Washington DC, so we all had to stay in a random hotel for 14 hours. Worse still, the plane was a type that didn't normally fly from Shannon, so there was some issue with the catering the following day (I don't remember what, but I remember not getting any food!)
Title: Re: Interesting flightpath (adjustment)
Post by: Mr Larrington on 18 June, 2023, 05:13:19 pm
Once got turned back an hour or two out of Hong Kong en route to, IIRC, Bangkok*.  Friendly airports were lacking in China and Vietnam in 1973.  OTOH my folks got stranded for a Several of days in the Maldives, with nothing to do except swim, loaf on the beach and drink the RAF's gin until a replacement aircraft showed up from Brize Norton.

* On a VC10, which had to stop quite frequently for more petril.
Title: Re: Interesting flightpath (adjustment)
Post by: JefO on 22 June, 2023, 11:58:08 am
... OTOH my folks got stranded for a Several of days in the Maldives, with nothing to do except swim, loaf on the beach and drink the RAF's gin until a replacement aircraft showed up from Brize Norton.


My last visit to the Maldives was when the Icelandic volcanic eruption prevented flights across Europe. Unfortunately, we were already out there when the thing popped its cork. So my wife and I got delayed for a Few of days, but at least we had SCUBA diving as a distraction from the eating, drinking and swimming.

Whilst we were there, one of the staff recommended tomato as a sunburn relief.

We ordered some sliced tomato on the room service.

It arrived, and we used it to relieve the stinging. We placed the used tomato slices back on the plate that it had arrived on.

The room was cleaned while we were busy at diving the reef, and when we returned, the plate was still there, but the tomato had been eaten.

 :sick:
Title: Re: Interesting flightpath (adjustment)
Post by: TimC on 02 August, 2023, 01:05:33 pm

Interesting why they would do that.

For a full on emergency, Shannon or Dublin would be closer diversions.

J

Came across this thread while I was looking for something else. For those who aren't aware of me, I am a retired (2020) Virgin Atlantic Airbus Captain and previously RAF pilot. I have flown this very aircraft (G-VKSS) many times.

Diverting an aircraft with around 260 people on board is a major event, both for those on board and the receiving airfield. The A330-300, while not among the very largest aircraft, is extremely substantial and not easily accommodated by that many airports in UK. Unless the aircraft is about to fall out of the sky, or (in a medical event) our ground-based medical experts advise it, we will try to divert to somewhere on our network so that there is both engineering and passenger support. Out of Heathrow, that basically means returning to Heathrow.

An engine vibration alert is not a serious event, but taking a two-engined aircraft out over up to 8 or 9 hours worth of Atlantic Ocean, often three or more hours away from an emergency diversion airfield (the A330-300 now has 210-minute ETOPs clearance, I believe, while the A330-900 is 285-minute) is hardly the action of a safety-minded pilot. Turning round to Heathrow still leaves plenty of options should the vibration deteriorate, but remember that the aircraft is certified for single-engined flight over water for over 3 hours, so an engine shutdown, should it be needed, is not a disaster.

Title: Re: Interesting flightpath (adjustment)
Post by: Beardy on 02 August, 2023, 03:11:02 pm
Tim, how is that single engine operation time limit derived. Is it a purely theoretical figure devised by the mathematical skills of the engineers, or does some lucky individual have to fly an example of the aeroplane in question on one engine for the time specified? Curious minds and all that  ;D
Title: Re: Interesting flightpath (adjustment)
Post by: TimC on 02 August, 2023, 03:38:55 pm
The process of achieving ETOPS certification is described quite well here (https://simpleflying.com/etops-certification-requirements/). The reason it's categorised by time limits is simply that the chances of a failure increase with time, so limiting the time of exposure is the simplest way of limiting risk. Getting and maintaining ETOPS certification is expensive for operators and manufacturers as the requirements are so strict and need years of proven experience to justify awarding. When Virgin first got the RR Trent 700-powered A330-300, back in 2011, it could already demonstrate many years of reliable operation using the very similar RR Trent 556/560 on the 4-engined A340-600 fleet, so it fairly quickly achieved an ETOPS certification.