LHR LGW Diversions

[Father Charles Pawnee]

Any CCF controllers care to comment on this one? A company plans all its aircraft with LHR destination and LGW as alternate. Will LGW accept these aircraft when the delays prevent an approach to LHR?What about LGW traffic diverting to LHR, is that an option?

[eyeinthesky]

First point is that to plan LHR/LGW as alternates to each other seems a bit daft. If the weather's bad at one it's likely to be bad at the other as well. Try somewhere further away, like BB/CC.

If you must have LGW/LHR as alternate then I suppose the ultimate answer is that a diversion should always be accepted up until the airport is full. Be aware however that BAA might have other ideas about what can and can't land, especially at LHR. I have had a lot of experience of the other airports around London turning traffic away because they get full (like when KK runway was blocked with a BAL 767 in December). I have also heard of flights being allowed to land at LHR but then been unable to get a runway slot (controlled by BAA, not ATC) for departure. Admittedly this was an ambulance flight inbound which was not an ambulance flight for departure and had to wait a few hours/days to be allowed out, even though ATC could easily accommodate it.

Beyond, that, I'm sure there are other contributors better qualified than me to comment further.



------------------
"Take-off is optional, Landing is mandatory"

[Take 5]

As an aside but still to do with alternates..had a VIR coming back from the US that informed me that he was changing his alternate to 27L. I tried to clarify this and he stated his "destination was EGLL 27R and his alternate was now EGLL 27L" Sounded fishy to me so I left it at "Roger" Any ideas on the legality of this ? T5

[static]

Eye, planning LGW as altn for LHR is only daft in bad weather conditions, for the reasons you gave. However on a nice sunny day, there`s nothing wrong with it. It saves fuel (environment). As every IFR flight has to have an altn, it`s best to pick the closest suitable one, especially if there`s only a remote chance of ever having to use it.

Planning 27L as altn for 27R is illegal however.

[5milesbaby]

PLANNING 27L as alternative to 27R isn't allowed, however once close to LHR, crews are permitted to 'ditch' the diversion airfield if both runways are servicable. This is in cases when the delays are long but not due to visibility, therefore they can calculate longer holding as no need for diversion and subsequent holding fuel. Sounds dodgy to me, but apparently perfectly legal!!

[Take 5]

Thank you 5milesbeby, that does fit the scenario and I suppose it does make sense as if both runways are serviceable then you can go safely to the limits on fuel as you are as certain as you can be that you won't be forced to divert - even in emergency.

Cheers T5

[Capt Chambo]

It is perfectly legal to, at the PLANNING stage of a flight, nominate LHR as a landing alternate for LHR. This can only be done provided certain criteria can be satisfied, but it is certainly legal.

It is also perfectly legal to ditch your alternate if you are in the hold at LHR. Again certain criteria have to be met before the Commander may do this but it is certainly legal.

The above cases also apply to LGW.

Whether it is sensible or good airmanship, is of course, another matter.

[Father Charles Pawnee]

I do no think it is legal at the planning stage to nominate independent runways at the destination as DEST and alternate, it is perfectly legal though after departure to re-plan everything with an adjacent runway as the alternate, under certain conditions.
The question still remains, any ATCO, what are the chances of a routine diversion between LHR/LGW?

[Capt Chambo]

Rereading my own post here I realize that I have made a mistake, and that you are correct Father Charles Pawnee.

At the planning stage you do not nominate a second runway at your destination as your alternate. Rather, provided a number of criteria can be met at the planning stage, it is then possible to depart for your destination without a destination alternate. Among the criteria that must be satisfied, is that the destination has separate runways. In this respect both Heathrow and Gatwick comply.

[static]

Chambo,

Glad you corrected yourself.
This "replanning in flight" is often used in a very creative manner though, for which it is not ment to be used.
Example: A 737 wants to fly non stop say, LHR-TLV, alternate Larnaca. But it is unable to plan it this way, because it would require a take-off weight in excess of max structural. So, an ATC plan is filed correctly, LHR-TLV, altn Larnaca.
The operational flightplan however, is LHR-Larnaca, alternate Nicosia. The crew gets a second flightplan with them, so they can decide during flight if it`s possible to continue the flight to TLV without alternate, thus making use of this replanning in flight rule.
Now there are several things wrong in this scenario: This is not replanning in flight. ATC is unaware of the aircrafts inability to reach it`s filed destination.(nice in case of comm failure) You plan your flight in a way that gets you arriving at TLV with absolute minimum fuel.

Now I`m sure out there are guys that use this way of operating on a regular basis. Any comments?