jpgmultimodal 61 Posted October 15, 2014 Share Posted October 15, 2014 Good morning all, May be I am doing something wrong but I cannot manage to have set altitudes to appear on the OFP when descending. I planned a flight between EGAC and EGPH at FL170. I need to be levelled at 6000' when reaching TLA. I entered in the field "TLA" the altitude 6000 but it does not appear on the OFP which states that the TOD is only 8Nm before TLA. Thank you for your help. Enclosed screen captures. Regards, JP Link to comment Share on other sites More sharing options...
FlyPrecisely 124 Posted October 15, 2014 Share Posted October 15, 2014 Looks like descent altitude capture is not allowed, only the cruise part. Link to comment Share on other sites More sharing options...
jpgmultimodal 61 Posted October 15, 2014 Author Share Posted October 15, 2014 Apparently you are right. It looks like altitude constraint is allowed in climbing but not in descent. Wait and see if someone can explain. JP Link to comment Share on other sites More sharing options...
srcooke 422 Posted October 15, 2014 Share Posted October 15, 2014 Descent restrictions can be achieved JP but probably not assigned in the STAR Link to comment Share on other sites More sharing options...
jpgmultimodal 61 Posted October 15, 2014 Author Share Posted October 15, 2014 Hello Steven, You are right as the TWEED2B gives you FL170 by TUNSO and after it is the ATC directing you in HDG and FL/Alt. For planning purposes, as I know that ATC is going to clear me 6000' at TLA and then direct procedure to 06 or 24, I would like to enter 6000' at TLA to have a better fuel calculation as levelling at 6000' then 4000' (06) or 3000' (24) for about 10 minutes I am going to burn more fuel than from the TOD to the Rwy as I would be more or less idle during a continuous descent. With the Dash it is going to be only about 50 kg more fuel so I can add these 50 Kg in extra fuel or add 20Nm Circuit In. Last flight that I did on this route I was about +20 or +30 Kg above the calculations in flight up to TALLA but when landed I was short 39 Kg. No problem at all as I had 75kg cont. But I was doing the return flight without refuelling and I had the fuel for the return flight added as extra fuel on departure from EGAC and I was short few Kg on the ramp at EGPH before departure. As you probably know (RW) you have to justify your fuel calculation. When you have this calculation made you can use your fuel as you wish (i.e. holding over destination or diverting to an alternate) but when you reach 0h30 fuel left you have to declare an emergency and then if you have less fuel on departure than calculated you are in trouble. I know it is only a sim but if you want it to have it right that is the way. If it is not possible to enter an altitude constraint when descending, we just have to add some Nm in the "Circuit In". Anyway on some airports like LFPO or LFPG it is necessary to do so as ATC would send you miles and miles away. Regards, JP Link to comment Share on other sites More sharing options...
ogruetzmann 11 Posted October 23, 2014 Share Posted October 23, 2014 Hi, it's a bit misleading in PFPX (and even in flight plans), because these are not altitude constraints, but mark the point where you want to start the level change. So what you entered there actually means that you want to start descending to 6000 feet at TLA, which PFPX ignores because it makes no sense for a normal profile. From the IFPS manual (http://www.eurocontrol.int/sites/default/files/content/documents/nm/network-operations/HANDBOOK/ifps-users-manual-current.pdf): Changes to the speed and/or level may be indicated in the route field of a flight plan or associated message submitted to the IFPS for processing; any such change of speed and/or level shall be associated with a specified point in the route of that flight. Changes to speed/level shall be specified at each point at which either a change of speed and/or level is planned to commence. Link to comment Share on other sites More sharing options...
jpgmultimodal 61 Posted October 24, 2014 Author Share Posted October 24, 2014 Hi, Thank you for your answer. The IFPS manual from Eurocontrol is not applicable in that case as the TLA WP is within the STAR. I just need to be levelled at 6000' at TLA to be able to join the ILS. As I mentionned in my previous post it is mostly for fuel calculations to be more precise as we burn more fuel than in a continuous descent. Regards, JP Link to comment Share on other sites More sharing options...
ogruetzmann 11 Posted October 25, 2014 Share Posted October 25, 2014 Sure, but you don't enter a constraint in PFPX, but a point at which you want to start the descend. But it shouldn't be that important anyway, PFPX will calculate a normal profile, which should be close enough. Link to comment Share on other sites More sharing options...
jpgmultimodal 61 Posted October 26, 2014 Author Share Posted October 26, 2014 Thanks Mr Ogruetzmann, I have it now. I just enter the point for the TOD and in this case TUNSO / 6000' and it does the trick to be levelled by TLA at 6000' and an extra burn of 33 Kg which is right. My mistake was that I thought you enter the WP and the FL/Alt and you were at that FL/Alt by that point. Everything is clear now. Thanks again. Regards, JP Link to comment Share on other sites More sharing options...
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