I have noticed lately that simbrief is giving very low cruise FL.
For example on my flight from EPKK to EHGG it gave me FL280.
I set it manually to FL340 without any issue. In fact, the airtime and block fuel were lower.
Any idea why this is? As far as I know I still generate flightplans like I used to do but maybe I have been doing it wrong all the time?
This flightplan was for a fenix A320SL with CI 25 and fuel adjusted manually to M2 (the default profile has M3 but that always gives me low fuel warnings)
Hi, it was due to an old manual airway cap on airway T738.
I have removed the cap and also added an IFPS compliant route for this city pair.
Best regards,
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Thank you.
Another question, just so I better understand it. Why would loading 200kg of fuel extra, lower my cruise altitude by 8000ft? I understand I need to tank a bit extra to carry the 200kgs but it seems to me like a severe penalty. But I am not the professional here so I am curious as to why 
My guess is the M02 in my aircraft profile has to do with it, but I am not sure.
Same here with the Fenix A320 IAE Sharklets airframe and step climbs disabled. A bit weird.
One thing to keep in mind is the M867 airway is limited to FL280 and below, the route should really use UM867 instead (with which the issue does not occur).
If you enable step climbs, Simbrief will plan FL370 and then descend to FL270 at MEDUX which is technically the correct thing to do due to the bad route.
What happens with step climbs is still unexpected, IMO. Typically, Simbrief would either keep the whole route below FL280, or not, and 200kg of extra fuel usually doesn’t have that much impact.
I’ve removed the VATSIM route but the behavior should still be reproducible if you plan with it manually:
LUPIX MEDUX M867 KOGAT TALAS UM749 ROPOX
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Regards,
Tim
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I see the problem now. Thank you
