Cost of a diversion VS holding

[LEM]

Hi all, I was just wondering if anybody figured out more precisely after how long it becomes uneconomical to continue holding instead of diverting to the alternate.

This for a typical european scenario, on a B737 with average good pax load, considering the cost of fuel, the delays, the ground transportation etc....

Some people tend to divert too early, IMHO, and I think up to let's say two hours holding is better than diverting.

Your opinions?

LEM

[TopBunk]

How long to hold - a difficult one. Assuming you have the fuel, then it will be cheaper to hold than divert, although I doubt if anyone can hold for 2 hours inbound to LHR!

When you have an EAT (Expected Approach Time) that is later than your fuel allows, then hanging on is basically in the hope than it comes forward because of a weather improvement or loads of others diverting. As a strategy this may work but then again may not. In these circumstances, an early decision to divert can often result in you getting to destination quicker after a splash-and-dash.

[HEATHROW DIRECTOR]

<<although I doubt if anyone can hold for 2 hours inbound to LHR!>>

I've seen very close to it!

[mutt]

doubt if anyone can hold for 2 hours inbound to LHR!

Absolutely no problem! We tanker LOTS of fuel into LHR, holding for 2-3 hours in a B777 is easy!


Mutt.

[Old Smokey]

LEM,

There's too many variables in the equation for a specific answer. For one, there's a helluva difference between diverting to an airport 50 miles away to 'sit out' an hour long period of lousy weather at the destination, and a diversion to an alternate 600 to 700 miles away.

Another big factor is local knowledge, at one of our regular airports, when the fog rolls in the airport remains closed tight for at least 3 hours. Much better to divert to the 120 mile away alternate than going around in circles at great cost to the company when you know there isn't a chance of getting in for at least 3 hours. More dynamic situations like passage of fronts etc. you know are going to clear in an hour or so, and it's better to hold whilst it all passes in the knowledge that you have a very high probability of a successful approach in an hour or so.

Each Airport / Traffic / Weather situation is different, too many variables to arrive at one common solution for all cases.

Mutt, you wouldn't happen to work for an airline from a certain oil-rich country would you?:O

Regards,

Old Smokey

[mutt]

Old Smokey.....

Yep.....


Mutt. :):)

[fireflybob]

I suppose you also need to take into account any "knock-on" effects. If the aircraft ends up in the wrong place when there is another service scheduled out of the original destination and/or the crew runs out of hours etc!

As has been said, it all depends but generally my gut feeling is that if you have the fuel it is worth holding if you expect the wx will improve or you will eventually get an approach.

Its also worth thinking tactically sometimes - if you have oodles of fuel to hold with and everyone else diverts then you might end up at the beginning of the queue when it all opens up again!! Mind you this can also be a reason to divert early. I remember wanting to get to LGW one night a few years ago. It was obvious to me that the weather was not going to improve for a while so I diverted to BOH before the rush. It was quite entertaining sitting on the ramp at BOH watching everyone land after us. We were first for fuel etc., got ops to file the plan to LGW and then we were first to get airborne again on our way to LGW when the weather picked up.

In a nutshell, this type of decision is part of captaincy - you dont always get it right but you learn from your mistakes, hopefully!

[FlightDetent]

What a colourful global business this is... ( tankering out of LHR...)

Anyhow, do you prooners know weather the new Denied Boarding Compensation rules would apply when A/C diverts, crew CHPT.7 limited and hence you dont serve the return leg out of the planned destinaton?

Cheers,
FD.

[stator vane]

way back in 2001, i was told that any diversion would add up to a minimum of 3000 pounds sterling. from a reliable director of operations for an unnamed airline based in brussels with a slight red tint. what with airport landing fees which might be higher for unscheduled flights, extra ATC charges, supply/demand fuel pricing factors etc.

i have asked present airline and they seem to think that we don't need to know that information. treat us like mushrooms they do.

D.I.Y. airlines these days

[Ignition Override]

Maybe your discussion is not only academic, and must be considered in Britain, but as a captain (although based in a 'colony'...), I have never let the cost factor influence my decisions on when and whether to divert-and never will, either. Not if I'm responsible for the ultimate safe end to a flight. I've diverted three or four times. If cost were a factor, the 'bean-counters' would share ultimate responsiblity-but that won't happen..

We try to contact Dispatch long before we reach such a fuel quantity and beware of some (US) Dispatchers "Decision Fuel" figures: these do not reflect true, unanticipated real-world factors, such as ATC denying us the planned altitude and direct routing, or whether the divert route is through crowded airspace and/or in an area of strong thunderstorms.:uhoh: .

Let's make sure that the divert airport has an ILS, or something better than a da^^&#d NDB approach-that is one way to get in a very serious corner with no way to fly a 'real' approach or go anywhere else, based on fuel. Some Rocky Mountain airports (Kalispell, MT) can have unforecast fog from a nearby lake, or unforecast snow-with the runway lights covered up, and no alternate fuel planned to return over the mountains to Great Falls.

Maybe all of this is totally irrelevant, because the 'real world' of airline flying only exists north of France :D . If safety clearly comes first, without any quibbling, then who cares about the cost?

[Captain Airclues]

HEATHROW DIRECTORI've seen very close to it

Were you on duty on 8/12/91? We held for two and a half hours at BNN (JFK-LHR). RVR went below limits at 600ft but saw the runway OK at DH (still had EGCC plus others as diversion). Wx was only above our limits for about 20 minutes for the entire day.

Airclues