Sorry to bother again but I kind of ran into an issue just now calculating APU fuel for an ETOPS release using the SWA OFP format.
Real quick, have you guys added any APU fuel burn behind the scenes when you are planning ETOPS with the SWA OFP format?
As well, since we cant see the ETOPS APU fuel anymore on the release with the new format, I would like to request a feature where we can set in the “Saved Airframes” an APU scenario function. I was thinking a dropdown that has the following options for ETOPS scenarios:
APU OFF
APU ON from Gate to Gate
APU ON from Gate to LAND
APU ON from Gate to EXP
APU ON from TOC to EXP
APU ON from EEP to EXP
This would be SUPER helpful and would be accommodating to all users, not just Southwest Airlines simmers.
What are your thoughts on this idea, Derek?
Thank you for all you do for us sir! Have a great day @SimBrief !
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For ETOPS, 3 AC power sources are required.
Most, but not all, guppies (737s) have been retrofit with an enhanced APU start circuit, called APU ON DEMAND EQUIPPED. It is an enhanced inflight start mechanism that negates the requirement to run the APU in ETOPS, unless required by the MEL or the ETOPS CMP document. Looking at an old SWA IFOM, their cockpit checklist card required the APU to be ran from start-up to the EXP. Ouch, that’s not cheap.
Yes, that is correct.
How a real world ETOPS-qual’d SWA pilot explained it to me, SWA has not proven to the FAA’s CMO POIs that they can safely start the APU at cruise altitude during a critical ETOPS scenario so for that reason, SWA has to have APU running from on the ground all the way to the EXP.
There are other airlines that have to do this too but I’m not sure which ones they are.
That being said, this would be a very helpful option for all ETOPS users, where applicable.
A dedicated option for this probably won’t be added for a while.
For now, you can do it manually by adding “APU” fuel and setting the time, in minutes, that APU will be running. Setting the fuel type to “APU” means that the time-based entry will use the APU fuel burn rate, rather than other extra fuel types which use the aircraft’s burn rate.
If we specify APU in the drop down, we no longer can put EXTRA fuel on which is for departure delays (not protected by min takeoff fuel). Technically if pilots dont do the math they can go negative, and then that can cause even more issues. so, what if we put the APU as a dropdown where MEL fuel is since MELs are not incorporated into Simbrief yet?
MEL and MEL codes are not incorporated as nothing can be entered into the MEL section of any OFP and MEL Fuel cannot be added without proper or substantial documentation for selected aircraft chosen and MEL issue selected. MELs should have their own section, hopefully that is in the play book later on down the road.
so right now EXTRA fuel → Downdrops → APU fuel
maybe switch so MEL Fuel → downdrops → APU fuel
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Yes I completely agree with you @swaluver480 and like that idea. You are absolutely right.
The other thing we could do, Derek, is we have a dedicated entry field specifically for APU fuel. It could go in between MEL Fuel and ATC Fuel in “saved airframes”. That way users can have EXTRA fuel, APU fuel, and MEL fuel all on the same flight, if they’d like.
What are your thoughts on this @SimBrief? That would probably be much easier to accomplish for the time being, right?
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Hi @SimBrief . Any chance we could get an update on this thread? Thank you sir!
This is not likely to come soon, we are currently focusing on other aspects of the system. It’s on the list to be looked into when able.
Best regards,
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