Significant fuel burn discrepancy at FL200-FL240

ProfCrash

What sim version are you on? Your IOAT is about ISA+5. In your 20,000 foot case, your CDU shows closer to 12000 lbs not 13000. Looking at your data and iterpolating for ISA+5 at 12,000lbs and 20,000feet I show The following: IOAT 13C, Torque: 44%-45%, FF/Eng 299lbs/hr, total 598lbs/hr, IAS 178, TAS 243.

Mad_X

and a +5 deviation does not account for fuel burn that is less than half.

ProfCrash

Thanks that might help @Black-Square. I agree the temperature delta doesnt account for the difference, I was posting the interpolated results for better comparison

MD82

@Mad_X Check out item 3 of a write up I've made a few months back.

One Request, One Observation

It's almost identical I believe as yours. But the funny thing is, my fuel used did agree with the tables. Just not the indication. Have a look at item 3 of my post and try to do the same. Doesn't need to be as complex. You can take remaining fuel at the start, then (leaving power constant) take another reading 15 minutes later. That difference in fuel remaining, multiply it by 4 to get your 2-engine fuel burn in pounds/hour. Divide that by 2, and you get the average engine fuel flow. That value should match the fuel flow indicator (and also your tables).

For me, it matched the tables, but not the indicator. As you can see from my post, I didn't hear anything back other than that it should work normally.

Mad_X

@Black-Square Nick, did you have the chance to look into this? I love the starship and my only gripe is this issues that when trottling back the fuel burn just is really off. Thanks so much

Black Square

I'll take a look later. I'll be honest, given the discrepancy is so large, I was hoping you guy would find something on your side that explained it, especially MD82's comments. I'll dig in later.