Request additional Citation Longitude Profiles

Good day,
With the AAU1 update I wanted to ask if additional climb, cruise and descent options could be added to the Citation Longitude in SimBrief, in accordance with what is now available in the updated Garmin G5000:
Climb: Cruise Climb (250/300/.80) and Max Rate (250/270/.76)
Cruise: .84 option (Default in sim)
Descent: .80/300 option (Default in sim)
Many thanks,
Jose

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I don’t understand why we can’t put our own profiles into simbrief…

It looks like they added a new “MCR” (max cruise rate) profile to the longitude. Fuel calculations seem to be wonky though. It over-estimates fuel used at or near max flight level (430 +) but underestimates below that.

It gave me FL360 for a 3 hour flight presumably due to winds aloft, but has me ~300lbs short on fuel (after accounting for FINRES+ALTN)

Hi,

On your YBKT-YBRY flight (the one at FL360), you had no route set in the “Route” option. This can happen rarely if SimBrief can’t find a route in a reasonable amount of time. Work is ongoing to reduce/eliminate this from happening, it’s already quite rare.

When no route is selected, the “Detailed Navlog” option is deselected (since there are no waypoints) and the fuel calculations become much less accurate. In these cases you can try to generate your own route using the “Route Finder” section, or use another route finding tool such as Navigraph Charts, FlightAware, EDI-GLA, etc.

With that said, it’s still possible for there to be some variance between the SimBrief calculations and what you’re seeing in the sim. Flight simulators (MSFS in particular at the moment) sometimes have a hard time reproducing accurate fuel flows across the full range of weights, altitudes, and speeds, so they don’t always perfectly match. This of course depends on the add-on in question as well, some are tuned better than others. I’m not sure how the C700 does in this regard.

Cheers,

Does this also interfere with step climb calculation? I just ended up with another DCT flight crossing AU in the other direction. It gave me initial FL370 but doesn’t have a climb above that.

I’m not sure why it picked 370 in the first place… even at MTOW the longitude is perfectly happy at FL410/M.84

According to folks in Working Title discord, the stock MSFS longitude is “Quite close” to real world burn rate. At M.84, the difference between FL370 and FL410 is about 440 PPH. It’s another 360 PPH between FL410 and FL450, which can be reached once total weight is below 35,000lbs.

Yes, stepclimbs are disabled if there is no route. Altitude capability is also much more conservative. The entire flight profile and fuel burn calculation is greatly simplified, and doesn’t account for interpolated winds, aircraft weight reduction over time, forecast winds depending on flight duration, etc. Basically, this flight can’t be used to judge whether SimBrief’s profile is accurate or not. It’s much too averaged and conservative.

Some users like the option to disable the detailed navlog calculations since they just want a rough estimate, but it isn’t suitable for the level of accuracy you’re looking for. :slight_smile:

For what it’s worth, I don’t believe that is correct. Data available online puts it closer to 200 Lb/Hr difference between FL370 and FL410, and 180 Lb/Hr between FL410 and FL450. This is what SimBrief has programmed right now.

Best regards,

One more for the lack of step climbs here.
I planned a flight from KCEA-LPHR (with a proper route with airways, navaids and waypoints, not just a DCT route. As said, according to performance tables, the Longitude can get to FL450 from 35000lb GW. However the cruise planned by Simbrief is a “static” FL410. If I want to go to FL450 later in the flight (which is mandatory if I want to have enough fuel for the journey) I have to insert manually a step climb where the GW gets down to 35k Lb :thinking: