Oceanic reclearance?
Thread Starter

Joined: Mar 2005
Posts: 553
Likes: 0
From: UK
Oceanic reclearance?
For those of you operating ETOPS across the NAT HLA, I have a question...
-If you receive a clearance that differs to the one that forms part of the route on the OFP, do you have to manually recalculate the critical fuel scenarios and ETPs?
-Does the dispatcher take into consideration the possibility of a reclearance to an adjacent NAT track when calculating fuel requirements, or would the usual 5% CONT be enough to cover this? Obviously the EEP and EXP can easily be determined from the range rings drawn on the plotting chart.
-If you receive a clearance that differs to the one that forms part of the route on the OFP, do you have to manually recalculate the critical fuel scenarios and ETPs?
-Does the dispatcher take into consideration the possibility of a reclearance to an adjacent NAT track when calculating fuel requirements, or would the usual 5% CONT be enough to cover this? Obviously the EEP and EXP can easily be determined from the range rings drawn on the plotting chart.

Joined: Apr 2009
Posts: 645
Likes: 16
From: Canada
I don't believe potential reclearances is a part of fuel planning calculations. So no you certainly don't have extra fuel specifically in order to fly other routes (i.e. no regulations require it, unless your company does)
You really have to look at the situation from the angle of what you do once your in the air vs. planning on ground. As for calculation of ETPs, the reality is that I don't think there's a tool that could be as accurate as flight planning software. You can use the ETP circles, that'll help, and use the average winds in order to get a decent estimate. But in any case, once your in the air go anywhere that meets ETOPS requirements and that'll fulfill your needs.
You do bring up a good point and one that I haven't thought about, namely, what if a reclearances takes you further away from your ETOPS alternates. As for your contingency it might or might not cover the extra fuel required. It's not there for any specific purpose. In any case you can use it up for whatever purpose is necessary during flight (and even before). The reality is that it's up to the crew to work out (using whatever tools are available) to decide whether or not they can accept a reclearances.
You really have to look at the situation from the angle of what you do once your in the air vs. planning on ground. As for calculation of ETPs, the reality is that I don't think there's a tool that could be as accurate as flight planning software. You can use the ETP circles, that'll help, and use the average winds in order to get a decent estimate. But in any case, once your in the air go anywhere that meets ETOPS requirements and that'll fulfill your needs.
You do bring up a good point and one that I haven't thought about, namely, what if a reclearances takes you further away from your ETOPS alternates. As for your contingency it might or might not cover the extra fuel required. It's not there for any specific purpose. In any case you can use it up for whatever purpose is necessary during flight (and even before). The reality is that it's up to the crew to work out (using whatever tools are available) to decide whether or not they can accept a reclearances.
Thread Starter

Joined: Mar 2005
Posts: 553
Likes: 0
From: UK
You do bring up a good point and one that I haven't thought about, namely, what if a reclearances takes you further away from your ETOPS alternates.
I guess my main question is, what is the operational procedure for re-plotting ETPs? I was under the impression that most operators place these in their FMS as a reference fix for situational awareness. If you're no longer flying your planned route, what do you enter? Would using the original lat/long with the <abeam> function activated suffice?

Joined: Apr 2009
Posts: 645
Likes: 16
From: Canada
You need to work out the ETPs using whatever methods you have available to you. I'm not sure about the capabilities of your FMS but on the aircraft I fly one can set a point abeam the original ETP. You're going to find it difficult to find exact coordinates. Any methods available to you in the aircraft are rough estimates.
If there are any 'operational procedure' to recalculating ETPs then your company would be teaching them to you.
If there are any 'operational procedure' to recalculating ETPs then your company would be teaching them to you.
Joined: Sep 2008
Posts: 629
Likes: 1
From: Been around the block
I assumed that this would be easier to determine, simply by plotting the new clearance on your chart. Is it not the case that you can check if it falls within the approved area of operation by comparing it to the range circles already drawn during the planning stage?
I guess my main question is, what is the operational procedure for re-plotting ETPs? I was under the impression that most operators place these in their FMS as a reference fix for situational awareness. If you're no longer flying your planned route, what do you enter? Would using the original lat/long with the <abeam> function activated suffice?
I guess my main question is, what is the operational procedure for re-plotting ETPs? I was under the impression that most operators place these in their FMS as a reference fix for situational awareness. If you're no longer flying your planned route, what do you enter? Would using the original lat/long with the <abeam> function activated suffice?
Joined: Mar 2007
Posts: 1,235
Likes: 0
From: USofA
"Usually"if the route is only 1 degree different, up or down Lat, the the recaluclation of the ETP is pretty meaningless, otherwise I would contact your dispatcher have them reclalculte a new ETP. It's worth noting that the CFP is nothing more than a plan when you push the power up, after that it becomes very dynamic and can vary significantly as you move along your track. Constant monitoring of you fuel and time scores are a must.



Joined: Dec 1999
Posts: 1,174
Likes: 123
From: uk
If you have the ALTN feature (our 767s and some 757s have, can’t speak for other ac types) careful programming of winds, temps and FLs will calculate time/fuel to a choice of ERAs and this effectively tell you when you are at an ETP. Our manuals show how to do the plotting/maths but I’ve never used that!
Joined: Sep 2008
Posts: 629
Likes: 1
From: Been around the block
don’t use those abeams if you’re cpdlc. If the reroute is really far, your ETP and ETOPs entry and exit points can change, as well as your ETOPs alternates. An oceanic reroute can be a real handful. I always remind the FO and IRO to make sure we copy the route on the ground in the FMC. That way, if we screw up the reroute, while plugging it in, we still have our original route. Lat long coordinates are a PITA to punch in on the ground and even worse airborne. We will talk to dispatch too, no matter what, even for a seemingly small reroute. Use all your tools. You might be on a C55 flight plan, where only the 10% fuel contingency is for class 2 nav. And then, it’s only 10% of your fuel for one hour into class 2 nav areas. If you fly off your filed route, you can be outside of class 1 nav and into a C55 scenario without knowing it.

Joined: May 1999
Posts: 241
Likes: 47
From: Runcorn,Cheshire,England
ETOPS is essentially a planning exercise only. I.e. can you legally dispatch. Once airborne ETPs are only as good as the forecast winds so trying to work them out to the nearest minute is pretty much meaningless. As long as you know where youre nearest suitable alternate is at all times then that for me is pragmatic and safe. ETOPS alternates are only applicable at the planning stage, once airborne, normal rules apply.

Joined: Feb 2001
Posts: 6,729
Likes: 105
From: The Winchester
In the UK and possibly elsewhere in Europe the lady or gent "dispatcher" (aka Turn Round Manager in some airlines) who was actually out on the ramp overseeing the loading of your flight out of, say LHR, would probably have some choice words for you if you rang him/her asking about a Oceanic re-route when you'd got to 30 west. The reason being it will have been a flight planning department that generated and issued your ETOPS plan and they won't get involved and also do not have to consulted about any in-flight re-clearance ..Accepting/planning a re-clearance is usually a DIY job for the crew using onboard assets...
As others have said, under the UK type ruleset pragmatically once you have dispatched the ETOPS planning becomes a bit irrelevant - you are free to use any suitable and available airports within 180 minutes of your route of flight and you can use the ALTN (alternate) facility of the FMC mentioned by deltahotel to keep an eye on ETPS, ERAs etc ...
I assumed that this would be easier to determine, simply by plotting the new clearance on your chart.

....would the usual 5% CONT be enough to cover this?
Last edited by wiggy; 20th December 2019 at 07:02.

Joined: Oct 2000
Posts: 81
Likes: 0
From: CYXY YT, Whitehorse Canada
no more doing the dispatch but in those days we were able to print out the flightplan with 3 nats option including the one selected, so in total two extra ones. it was for 767, 747 classic and 747-400.
Joined: Nov 2019
Posts: 3
Likes: 0
From: unknown
ETOPS is essentially a planning exercise only. I.e. can you legally dispatch. Once airborne ETPs are only as good as the forecast winds so trying to work them out to the nearest minute is pretty much meaningless. As long as you know where youre nearest suitable alternate is at all times then that for me is pragmatic and safe. ETOPS alternates are only applicable at the planning stage, once airborne, normal rules apply.

Joined: Dec 2006
Aviation Qualifications: CPL
Posts: 433
Likes: 0
From: Hamburg
In the UK and possibly elsewhere in Europe the lady or gent "dispatcher" (aka Turn Round Manager in some airlines) who was actually out on the ramp overseeing the loading of your flight out of, say LHR, would probably have some choice words for you if you rang him/her asking about a Oceanic re-route when you'd got to 30 west. The reason being it will have been a flight planning department that generated and issued your ETOPS plan and they won't get involved and also do not have to consulted about any in-flight re-clearance ..Accepting/planning a re-clearance is usually a DIY job for the crew using onboard assets...





