Guys I've been using the MD11 for quite a while now without any issues, I've read the documention many times on Longhuals and feel comfortable operating the aircraft but I came across a strange issue departing out of Memphis this evening and hope someone could shed some light.Here are the details -MD11F FEDEX (GE)GTOW 485500 lbs KMEM 18C Wind 048 8 knots TEMP 37C QNH1009 - Utopia gave me a Derate of 58C with Flap 15All looks good and entered correctly until I line up and set T/O Thrust, I notice the the FMC has given me a N1 of 58.7Now the aircraft is barely accelerating and I decide to reject at 80knots and taxi off realising the FMC is giving me ridiculously low N1 settings for Take off. After spending a while trying different assumed temps one of which gave me a T/O N1 off 48.8 I give up clear the Flex temps and go Max thrust (not past the overboost), N1 110.4 all 3 EGT redline on the take off role and then return to normal at climb thrust leaving a marker of 962 on the EGT.Now I've done hundreds of flights and the aircraft has performed perfectly so I can't figure out why it would start doing this?Also I haven't made and changes to FS9 itself.ThanksRob

If it only happened once, I'd just write it off as a sim hiccup. If it occurs again though, there's cause for investigation.Paul

Rob, is this something you can reproduce now, or was it just a one time thing? I don't remember running across anything remotely like this in the past. Definitely a strange one.

Landed in Detroit an hour later and while sitting at the ramp did a little test and created a short flight plan and set up the performance data, the Flex temps where still acting weird. Anyway flying on to Miami tonight so will see if it happens again now the machine has had a complete reboot. ThanksRob

Is 58C a little high for a flex temp? That's about 136 degree F.....Regards,jack

Is 58C a little high for a flex temp? That's about 136 degree F.....Regards,jack

No, you can Flex up to 69C depending on conditionsRegardsRob

Well I am sat at the ramp in Detroit doing my preflight, just punched in the 68C FLEX Temp that Utopia suggested and the aircraft is giving a Figure of 102.1 N1. I guess it's one of those random things, at least my install is not corrupt.Thanks for the suggestions.Rob

Good to know it was just a one-time thing.Now, I think I recall a thread in this forum by a real MD-11 pilot, who said they "rarely" use a flex higher than 50 in real life.

Well I am sat at the ramp in Detroit doing my preflight, just punched in the 68C FLEX Temp that Utopia suggested and the aircraft is giving a Figure of 102.1 N1. I guess it's one of those random things, at least my install is not corrupt.Thanks for the suggestions.Rob

Rob, what was your OAT at DTW?

MD11F FEDEX (GE)GTOW 485500 lbs KMEM 18C Wind 048 8 knots TEMP 37C QNH1009 - Utopia gave me a Derate of 58C with Flap 15

Is Utopia wrong with this?? That is a muggy warm day in Memphis, probably had too much spicy bar-b-que the night before. That seems like too much derate to begin with, not sure about the FMS response to the input either, ummmm.. maybe Rob had to much spicy bar-b-que?

Is Utopia wrong with this?? That is a muggy warm day in Memphis, probably had too much spicy bar-b-que the night before. That seems like too much derate to begin with, not sure about the FMS response to the input either, ummmm.. maybe Rob had to much spicy bar-b-que?

Lol spicy BBQ sounds good :( temp at Detriot today was 32C I'm in London so the local time there was around 2pm when I left.The flight was only 45 minutes to Indy today and the aircraft was nearly empty so dispite the high temps the Flex I got worked out fine, however like everyone else I'm very thankful for the work that guy put into Utopia for us but looking forward to using TOPCAT again. When Hot and Heavy I don trust Utopia and allways use TOGA.Rob

I have been using the FLEX calculation Excel file that a member put together and made available before the site was hacked... So far I have been using those assumed temps and getting reasonable N1 values...Not tried it with such high ambients, but they would only lead to a reduction in assumed temperature... You do not want to have too little thrust on hot days...Andrew