July 20, 20169 yr Hi, my last flight KJFK-LEBL with Delta 772LR went as follows, and I'm not sure if I did everything right: First of all, PFPX proposed a random routing, not a NAT, which I think was OK, because, a. The chosen random track stayed at least 1° of Latitude south of the eastbound NATs, and b. The westbound NATs crossed meant no problem either because they're valid between 11.30 and 19.00 zulu, and my flight was carried out between 00.00 and 05.43 zulu (crossing took place at around 04.00 z). I also let PFPX calculate a Redispatch Fix (4612N), with Redispatch Airport La Coruña / Alternate Vigo. I hope I understand the principle of a redispatch fix correctly when I think that you are safe to continue your flight to the planned destination when your amount of fuel at the redispatch fix is at or above the indicated amount in your flight plan? So, my flight plan said that the release fuel for the trip 4612N to LEBL was 32538 lbs (see attached picture). So, since at the indicated redispatch fix the amount of fuel in my tanks was about 30800 lbs, I decided that I had to divert to my redispatch airport LECO, which I did (what a nice view over the town). Did I apply the redispatch flight plan principle correctly? Finally, last question: when I approached the redispatch fix and already saw this could possibly not be enough, I wanted to make use of the RTE2 feature in the FMC, but I was unable to enter the new airport there. Instead, I was able to change RTE1 accordingly. What FMC-technique would you use in such a situation? Many thank for clarifying my doubts and questions! Regards Lars Wüst
July 20, 20169 yr There is a lot going on behind your query, so I'll brief at the expense of complete. The PFPX plan also has redispatch planning in the upper section, which provides a plan and minimum fuel at the redispatch point. It's possible that 30.8 klbs was at or near the minimum value and the flight could have been dispatched onward to LEBL. There is coordination between an actual dispatcher and the crew in real world because there are many factors to consider. In simulation, I look at my fuel required to destination, alternate and reserves compared to fuel remaining and make a judgment call. If assured I can safely shoot an approach, fly to alternate and land and the weather looks good then onward I go. This means I may be consuming some contingency but in my mind that is why it is there. I have found the best way to use the RTE2 feature is to do a RTE COPY right after executing the plan during preflight. Later, you may then easily change the destination in RTE2 and revise it to meet your requirements. The key is making sure that RTE2 is set up before departure for future use. Dan Downs KCRP
July 23, 20169 yr Author Thank you Dan for your input. Your description of considering the fuel for the different parts of the remaining flight is pretty much what PFPX says. So I think I did it right. Thx also for the RTE Copy method, I do that now every time in case I need it. Regards Lars Wüst
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