Take off alternate
 

Hi all,

I might have posted this in the wrong section but does anybody know when filing for a take off alternate what section does it get entered on the flight plan?

I was looking at the alternate section (16) and to me it looks like that is only for destination alternates but I could easily be wrong!

I had a look through CAP 694 but I couldn't see the answer.

Thanks in advance,

R

Presumably you mean you have diverted to your alternate and now wish to file for a departure? If so, just file it as a normal departure to your next destination. I don't think that ATC would be interested in whether your departure point was your alternate from a previous trip.

ribena, I suspect that you trained in the USA where it's a requirement. There was no such requirement on this side of the Atlantic, when I last saw a flight plan, even in LVP operations.

You must, of course, in LVP conditions, have takeoff alternate(s) which comply with the specifications in your ops manual.

Whenever I've had experience of a departure alternate being nominated, it was by way of a radio call to the tower prior to departure. The info was passed onto the next (departures/approach) controller by phone.

I don't think there's a formal place in the FPL for it. You could enter it in the remarks section, I guess. But it's just as satisfactory to let the tower know before departure.

If nobody knows, it's no big deal, either, IMO. If you have an 'event' requiring the use of a departure alternate during or immediately after takeoff, it's likely to be an emergency, and the ATC unit handling you will quickly ascertain what you want to do and where you want to go.

ATC generally doesn't have a plan, or "sanitize" airspace based on a nominated departure alternate. We just make a plan as required, if it happens. I guess that's why there's no formal space in the FPL for it.

No, I think the OP is talking about departing from an airport when the weather is below the minima required to make an approach at that same airport and is therefore required to plan a suitable alternate relatively nearby (IIRC within 30mins flying time on one engine, but i may be wrong). This allows for the fact that they won't be able to make an immediate return to the departure point in the case of an emergency. It's more of a concern for the airline's ops department than ATC: if you want to divert (at any stage of your flight) tell me where you want to go and I'll arrange it. At that stage I really don't care what's written on your flight plan.

ICAO Annex 6 Part 1 1.3.2
 

The take-off alternate shall be within the following distance from the departure aerodrome:

Aeroplanes with 2 power units
Not more than the distance equivalent to a flight time of one hour at the single-engine cruise speed.
Aeroplanes with 3 or more power units
Not more than the distance equivalent to a flight time of two hours at the one-engine inoperative cruise speed.

Typically, this is 250 n.m. for the 737/757 and 400 n.m. for the DC-10.

:ok: