.
ISSUE DESCRIPTION
Description of the issue:
In carreer mode you can only do missions with plane XYZ that have a distance, that suits the fuel tank and consumption of that plane XYZ. So far so good. But in the case of the Cessna 408 Skycourier this consumption estimation (the one you see, when you fill the tanks before the mission) calculates twice the amount that will be consumed in reality.
Example: The mission setup predicts, you will spend 80% of the fuel. After having done the mission, you will only have spent about 40%. This miscalculation leads to the effect, that you can not fly missions with the c408 that are longer than aboit 650 NM, because the estimation calculates, that your fuel tank is not big enough. If you fly the exact same distance in freemode you end up with huge reseves, as the pre-mission-fuel-estimator miscalculates roughly about factor 2.
This issue excludes the c408 from about 30-40% of all medium cargo missions.
FREQUENCY OF ISSUE
How often does this occur for you (Example: Just once, every time on sim load, intermittently)?
Always
REPRODUCTION STEPS
Please list clear steps you took in order to help our test team reproduce the same issue:
-
Try to take long distance cargo (medium cargo) with the c408 that would be physically in range of the plane, requiring more than 50% tank content. You can’t!
YOUR SETTINGS
PS5
A fully laden C408 has a published range of about 400nm (900nm is empty) so the pre mission calculation doesn’t seem like it’s far off at all - and with a 2500lb payload or so the range is something like 650nm.
From memory (i’ll try look this evening) a cargo mission doesn’t actually inject that payload as part of the flight - which could explain the fuel burn differences in the actual simulation. When you tested in free flight did you load payload?
Could this issue be related to this one ?: C408 - Total fuel figures don't add up?
No, this seems to be a different issue.
All fuel estimates for all aircraft are wrong.
Yes, they are all slightly wrong. But this one is so wrong, that it excludes the plane from many missions.
I haven’t played career mode in a while but you used to be able to takeoff with less fuel than you need if you didn’t fill it up from the menu. So you’re saying now that if I select a C408 mission that’s longer than about 650nm it won’t let me start?
Pretty much all of the calculations have been wrong since day 1. I used to get 172 cargo missions that said I need 6gal to complete the mission and it was over 100nm.
Exactly. If you try to start a mission with more (pre-flightestimator) fuel needed, than fits in the tanks, you are required to transport a different plane of your fleet here. Even if the c408 could do it in the game, because the pre-flight estimation is just extremely wrong!
It’s just like you want to drive from Berlin to Hamburg but you are not allowed, because Google maps calculates your VW Golfs fuel consumption with 30 liter per 100 km… so may not even start the mission.
yup just ran into the same thing with a under 600nm mission
I don’t recall but the PC12NGX was available to transfer, and I assume use. After a quick Google sesrch the 408 has a greater max payload and greater max payload with full fuel so if the PC12 NGX could be used the 408 should be able to be used as well
There will be a reasonable chunk of missions that the PC12 can do the C408 just cannot, but that doesn’t look like one of them. It’s hard to model without the precise calculation being used for the estimate.
The PC12NGX cargo has about 4700lbs max weight in sim so less fuel and less cargo, but the PC12 also uses less than half the amount fuel to travel about a third faster.
My back of envelope calculation, I think the C408 is about 10% high on the estimation based on the scraps of published figures for fuel burn rates, I can’t find decent numbers to work this out though.
The C408 also seems to use quite a bit less in the sim than the published rates but I haven’t tested this in any great detail.
ok Here’s one with more detail:
542nm
Still says not enough fuel
Details of the load
2868lbs of cargo… higher than the PC12’s maximum payload yet that’s allowed but within the payload limits of the C408. It says 2025lbs of fuel, not sure where they got that as I could select either the PC12 or PC24
In fact you can do missions at the edge of what the pre flight fuel estimation allows. As soon as you land, you will see, that you haven’t nearly spent 50% of the estimated consumption.
If @wcc96387 could have forced the mission start (which is not possible unfortunately), he/she would surely have completed it with a huge (!) amount of excess fuel in the c408.
But which is wrong, the estimate or the in-sim usage? I don’t disagree there is an issue, but the fuel usage in sim is a red herring.
The C408 should use something in the vicinity of 1100-1200lbs of fuel every hour based on published numbers. It’s obviously going to vary somewhat dependent on speeds, loadings etc, but I did a quick test and came out at something like 750-800lbs, much less than real life.
I think the bigger issue here is in the aircraft configuration
MSFS treats fuel and payload (cargo and passengers) as a combined ‘weight’. The calculation for what payload can be carried for a mission (i.e can the aircraft do it) is done like this, with the first being the preference, it only steps down to the second option if it can’t do the first:
- Max possible payload for a mission = max zero fuel weight - empty weight + minimum fuel required
- Max possible payload for a mission = max gross weight - empty weight + minimum fuel required
There is a related concept where the aircraft has a ‘max weight’, which is the combination of fuel, cargo, pilots it could carry for cargo missions (which is similar to the above).
In game, the C408 has a max weight of about ~6700lb of fuel, cargo, pilot/copilot. This is the main culprit because this isn’t how the aircraft is in real life.
It should be more like 7800lbs based on the numbers I can find published online. This missing 1100lbs of capacity would have a massive impact, it’s essentially an hour of range.
This is the same problem in reverse with the PC12. The game thinks it can have 4700lbs or so mixed payload/fuel/pilots. But IRL the max zero fuel weight SHOULD limit its payload to 2300lbs - so maybe this isn’t actually set correctly. But this would exclude the PC12 from almost all medium cargo missions so it might actually be done on purpose.
