Hello,
What is simbrief using to calculate the Cost Index for these flights exactly? there is nowhere to enter in the fuel flow rate, fuel burn rate for said aircraft which is also needed to calculate airlines CI.
for instance, it’s not just the cost of time divided by cost of flight. it also takes the fuel price, time of flight, fuel load (or how much fuel is estimated), fuel burn rate, etc. I get a lot of times the CI of 5 that simbrief spits out. never seen it higher than 14. now i use a few different websites and knowledge of dispatching to get my own CI which happens to be anywhere based off of 3 to 96 as well as the type of aircraft. im generally posting this to ask how does simbrief find the CI and what you guys are soleley basing it off of?
Automatic Cost Index is based on the specified Block Time, Simbrief tries to find the CI so that the air time matches the block time minus taxi time (both in and out).
The initial block time itself is automatically calculated (not sure how) but can be edited manually on the New Flight page:
Regards,
Tim
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interesting, wonder what it would take to revamp the aircraft to have options for the averages of fuel burn and consumption per hour rate, and also the price of fuel (skyvector is the only source i have used) to get a more accurate CI.
however with that info i will play more around with it.
hoping a revamp is already planned/in progress as i posted this and we just dont know it yet.
It’s also crew and fuel cost dependent in the real world. With a true optimized CI, as gas prices go up, opt CI goes down; and vice-versa. Most operators enter their fuel prices from their fuel management group into their FPS weekly at a minimum. We also have the time-based crew costs in the FPS as that drives opt CI. Most operators also have a delay cost value in the FPS; if you’re late being late will cost X per hour, which forces the FPS to drive a higher CI to not have to shell that out (pax missed connex, reacomm costs and so on).
Most Boeing airplanes have a default CI, that is nothing more than flying LRC, but in terms of CI to be able to use some of the optimization routines in the FMS. But it’s not cost-based at all. Operators also have “LRC” removed as an option in the FMS to enforce you fly CI - even if its a default value.
For example, the 752 and 763 default CI is 80; but its nothing more than LRC - as the CI80 curves are parallel to those model’s LRC in the FMS substantiation document.
okay, so with all of this information i hope that simbrief in the future will update their options to include this data for a more accurate CI. that as Tim said, its by flight time and to make it as close as possible to that time
I respectfully disagree.
Real flight planning systems using real world performance data and true manufacturer algorithms directly from the manufacturer and cost millions of dollars a year to utilize (most FPS systems model prices based on fleet size and ops complexity), roughly around 3-5M USD per year for a large worldwide operator, excluding cloud costs if they host externally. I doubt SBF could charge that.
What SBF has achieved is remarkable in its output yes, but in the end whether you fly CI50 or CI150; nothing changes for you. You don’t misconnect, your direct operating cost is still zero. You could fly whatever default CI you want; and my guess is few airplane-model designers are using manufacturer performance data to create that model in MSFS or whatever. Real electronic flight performance data used in FPS systems is proprietary, and more importantly its not cheap.
i agree but i also dont thinkl we should limit ourselves… Navigraph could implement a better system for CI. especially that most explicit system modeled aircraft in the sim actually uses these said so algorithms for CI. flight simulation can be a lot more technical Indepth dispatch wise than you think.
