changing alternate in-flight

[homerj]

Hi ,

Ive heard guys who are under pressure in the hold changing their alternate in flight to their destination.I presume its a legal thing to allow them to use their alternate fuel to keep holding if they are sure they will get in.

Havent had to do it myself but would like to be confident doing it if I had to.

Just wondering If you ATC guys have any info on it.
Regards
(JAA 737 operator)

[HEATHROW DIRECTOR]

Heathrow was landing 27L once and very busy. We asked a Concorde for his alternate and he said: "27R"! Otherwise never heard of such a case.

[chevvron]

Used to happen as the 'norm' back in the days of early 747s.
BA to LA or San Fran used to file SEA as destination with LA or San Fran as alternate, the reason being en-route headwinds might make them have to land at SEA to re-fuel. If fuel was OK, they'd simpy carry on to their real destination.

[Nubboy]

It all depends on the rules of the regulator your're under.

One of the most practical things we can do is bin the alternate, completely. As long as certain rules are met then you can commit to landing at your destination airfield and use your diversion fuel to hold. Quite often it's a sound thing to do, othertimes, (last winters snow in the UK for example) it would be sheer lunacy. Regardless of the rules, common sense should prevail and you shouldn't paint yourself into a corner.:ok:

[BOAC]

Homer - I think a little confusion has crept in here - in pure semantic terms you cannot 'divert' from your original destination to your original destination. I am not quite sure how the perception that these a/c are 'nominating' their 'destination' as 'alternate' is coming about - they are merely exercising the provisions of EU/JAA OPS whereby the conditions at destination are such that an alternate can be dispensed with in flight, as indeed it can at the pre-departure planning stage under EUOPS 1.295 (c) 1) and 2). In other words - I (may) have nowhere else to go except my destination (as nubboy said).

Chevvron has covered the 'replanning in flight' technique or 'en-route alternate' but that is not going to happen 'in the hold'.

[homerj]

The last time I heard a guy doing it , there was an aircraft blocking the runway so everyone had to hold while they moved it.The weather was fine and atc said the runway would be open in 30 mins so some diverted but some asked to change their alternate to the airport with the blocked runway.

Mabye they used the wrong terminology and ATC knew what they meant.I guess they got rid of the alternate as Nubboy says.
Ill have to get the EU OPS out.

Thanks for the replies

[BOAC]

but some asked to change their alternate to the airport with the blocked runway. -hmm! Makes mental note to try and avoid being flown around by them.:eek:

[Nubboy]

Without looking up all the rules, the main criteria for me to bin an alternate, would be to have an expected approach time (weather and other factors being neutral). For me at least I think waiting for a blocked runway to be cleared might be a moveable feast.

As an aside just having an alternate nominated on a flight plan means you have ticked various boxes about where you could divert to if required. Whether you would actually want to go there, if reqired might be a different matter altogether. The only advantage I can see in asking ATC to change your flight plan alternate is to pre warn them if a diversion is looking likely, and you have plenty of time. Otherwise don't waste the bandwith on congested frequencies. If you need to change it in a hurry, then just tell the folks what you need. The why can come a bit later.