What am I doing wrong here? 

I load up Topcat and tell it that I want to fly from KLAS to KLAX in the B737-800.  I put in a route:

 

BOACH5 HEC RIIVR2 at FL280

 

I give it an alternate:  KONT

 

Topcat told me that my trip fuel will be 5070 lbs.  Fuelplanner.com says it'll be 4300 but it doesn't know my load so I go with the higher of the two but plan to keep reserves that Fuelplanner recommends which is 6099.  The trip is 235 NM but there's a 40 knot headwind at altitude so I need some more.  I plan for an extra 1500 lbs just to be safe...that's a lot of extra.  I load up 13000 lbs, put 6.0 in the plan fuel and 6.1 in reserves.  Cost index is 80 if that matters which I don't think it does.  Cruise wind is 299/36.  I'm set up to depart 25R.  I keep getting messages...insufficient fuel, or using reserve fuel.  Double checking stuff....I've checked my route.  I have my takeoff data in...looks good.  V speeds are in and are pretty close to what Tomcat said they would be.  I probably have more fuel than I need for the trip.  What's wrong with my fuel planning?

Hi

Your using reserve fuel incorrectly. Reserve fuel is for the fuel used to divert to alternate + 5% contingency and 30 mins hold time.

 

Tutorial 2 has an In depth section on fuel planning

 

Tony

The amount you have in the tanks is fine.

 

You have told the FMS that you want to arrive at your destination with heaps and heaps of reserve fuel.

 

The FMS has calculated that you will not arrive at your destination with this figure.

 

Reduce the figure to something like 3 (metric) tonnes. (only more if your diversion point is further away than 200nm).

 

If you put 20 tonnes of fuel in (nearly full) and tell the FMS that you want to arrive at a destination 100nm away with 19.8 tonnes of fuel, it will tell you that there is insufficent fuel (in your tanks to arrive at your destination with 19.8 tonnes ...)

 

Of course 19.8 tonnes of fuel on board is probably going to be above max landing weight and enough fuel to hold for nearly 3 hours.

 

It will also tell you in your fuel prediction (PROG page) that you will arrive with something like 18.9 tonnes.

 

The number you set in the FMS should be only your holding and diversion fuel. It should only go up and down due to distance to alternate, and not wind

The amount you have in the tanks is fine.

 

You have told the FMS that you want to arrive at your destination with heaps and heaps of reserve fuel.

 

The FMS has calculated that you will not arrive at your destination with this figure.

 

Reduce the figure to something like 3 (metric) tonnes. (only more if your diversion point is further away than 200nm).

 

If you put 20 tonnes of fuel in (nearly full) and tell the FMS that you want to arrive at a destination 100nm away with 19.8 tonnes of fuel, it will tell you that there is insufficent fuel (in your tanks to arrive at your destination with 19.8 tonnes ...)

 

Of course 19.8 tonnes of fuel on board is probably going to be above max landing weight and enough fuel to hold for nearly 3 hours.

 

It will also tell you in your fuel prediction that you will arrive with something like 18.9 tonnes.

 

I, perhaps, should have used decimal notation.  I put 13.0 in the tanks, 6.0 for the trip fuel.  Not sure what logic flightplanner.com was using to come up with its 6000 lbs reserve figure but, as you point out, I told it 6.1 reserve.  Mathematically, that seemed like a no brainer.  But, following the logic then, KONT is about 75 miles I think (not at my sim) so, thirty minutes + 30 minutes hold time so...1 hour which means about 5.0 reserves?  5.0 + 6.0 = 11.0...5% more would be another .6 so 11.6 is what I should put on board.  If all that is correct then...

 

Trip: 6.0

Reserves: 5.0

Extra 5% (not entered in any slot in the FMC): .6

Minimum fuel to load: 11.6

 

In essence, tell it that I need a smaller reserve.  I can't get on my sim to see if that would work right now.  Doesn't seem that much different than what I originally put:

 

Trip: 6.0

Reserves: 6.1

Fuel loaded: 13.0

 

An extra 5% of 12.1 would be less than 0.7 but I'll use that figure.  6.0+6.1+0.7 would be 12.8.  I'd still have 0.2 extra.  Am I cutting it too tight?  Maybe variances between Tomcat/fuelplanner.com and the sim.  Perhaps I should add an extra 10% instead of 5% to give a buffer.

Trip 6.0

Reserves 5.0

Minimum fuel load: 11.6

Fuel loaded 13.0

Actual fuel reserve you will probably have when you arrive: 6.1

"Reserves" number entered into FMS: 5.0

 

Yes you actually have 6.1 fuel that may not be used by the aircraft if you don't go into holding etc, but 5.0 is the entry you want to put in there. This is the reserves you are using, the 6.1 includes 1.1 ton extra on the minimum reserve, but this includes the 5% variable and hold time.

 

You want 5.0 so that when you get to a point that only 5.0 ton will be left when you arrive, the FMS tells you and you can make a decision to divert (because if you divert after that you might not make it.)

 

This way you can sit in a holding pattern for 30 minutes before it goes off.

Trip 6.0

Reserves 5.0

Minimum fuel load: 11.6

Fuel loaded 13.0

Actual fuel reserve you will probably have when you arrive: 6.1

"Reserves" number entered into FMS: 5.0

 

Yes you actually have 6.1 fuel that may not be used by the aircraft if you don't go into holding etc, but 5.0 is the entry you want to put in there. This is the reserves you are using, the 6.1 includes 1.1 ton extra on the minimum reserve, but this includes the 5% variable and hold time.

 

You want 5.0 so that when you get to a point that only 5.0 ton will be left when you arrive, the FMS tells you and you can make a decision to divert (because if you divert after that you might not make it.)

 

This way you can sit in a holding pattern for 30 minutes before it goes off.

 

Ok...I'll try this when I get back on my sim.

What I finally got to work was 

Total Fuel 12.5

Trip Fuel 6.5

Reserves 2.0

 

I kept reducing Reserves until it stopped giving me errors.  Seems not right.

Hi.

 

Here is RW flight plan, we use it every day. This one I have generated today. You can cross check with your numbers. As for reserve it depends what rules you use. In US for domestic it is 45 mins so amount in pounds may vary. I also added 1.5 of extra as you did and I added 15 mins of contingency fuel for possible ATC delays. System picked forecast winds at 0500z so it was M17 kts not 40 but extra will cover the difference, especially for such a short flight.

 

TEST/23 LAS/LAX-KLAS/KLAX/                                        
                                                                    
FP TEST/23 LAS /LAX  ONT  345 B737-800W M78 PLN 0101
SUGGESTED TANKER Y  SAVINGS/COST PER 1000 LBS  P100.63     WXTYP BRG
                                                                    
BURN       0043  00.41    OEW   0957  LIMIT     FCST 2.91/3.63      
ALTN ONT   0016  00.15    PYLD  0330            TOTAL COST  002658  
RESV       0038  00.45    ZFW   1287  1383      ADDTL BURN    0012  
CONT       0013  00.15    FOB   0128  0460      CRZ ADJUST   5.4    
MIN  FUEL  0110  01.56    TOW   1412  1742      AVG W/COMP    M017  
TAXI       0003  00.13    BURN  0043            AVG ISA TEMP   P04  
EXTRA      0015  00.14    LGW   1369  1463      ENGINES CFM56-7B26 
GATE FUEL  0128  02.23    FOD   0082  1.29      EXTRA     P 151.03 
                          FOA   0066  1.14                         
                                                                   
                          PLAN 3 ISA P12 IP ON   TC 1462           
RT 101   DIST 0230                                                 
LAS.BOACH5.HEC.RIIVR2.LAX                                          
LAS/0280/                                                          
 

 

                                                        
 

 

I just use fuel planner and with the numbers they give I always land with around 7,000 pounds which is a comfortable amount to land with. As for reserves I put in 2.0 with a CI of 30, I never plan on diverting or holding while in the sim and I purposely avoid events on VATSIM so that one would not have to worry about these issues. As for bad wx I simply autoland or use the runway outline drawn on the HUD. 

Some screenshots of your filled out PERF INIT page and perhaps the PROG page would be really helpful in determining what's going on, methinks.

Thanks guys.  I'll try plugging it in again and take some screen shots.  I'll also try out those RW numbers. 

 

I just use fuel planner and with the numbers they give I always land with around 7,000 pounds which is a comfortable amount to land with. As for reserves I put in 2.0 with a CI of 30, I never plan on diverting or holding while in the sim and I purposely avoid events on VATSIM so that one would not have to worry about these issues. As for bad wx I simply autoland or use the runway outline drawn on the HUD. 

 

I might do that myself for a quick flight.  But, while I'm learning I do try to stay as 'by the book' as I can. 

 

 

I kept reducing Reserves until it stopped giving me errors.  Seems not right.

 

You are correct.  This is not right at all.

 

I'd really suggest the fuel procedure in Tutorial 2.  If you continue to use unrealistic fueling practices, such as using TOPCAT's estimates, or flightplanner.com (it seems this website is no longer active when I try the address), your realistic simulation of the aircraft is not going to behave how you expect it to.

 

The software dispatchers use has the exact same fuel logic that the FMC uses to calculate everything.  As such, the fuel numbers they hand the pilot are very accurate.  You can emulate this by using the FMC itself as your "dispatcher."  TOPCAT does not take into account filed altitude, wind and several other factors.  It's an estimate to give you a preliminary idea just in case you haven't run your fuel burn numbers yet.  I can't get to the web address that you mentioned, but I highly doubt it's using any sort of calculation other than rudimentary rules of thumb.

 

Tutorial 2 describes how to get accurate fuel through utilizing the calculations right in the FMC.  This will help you better fuel and fly the aircraft.  It will also explain several other things about fuel and route/cruise planning.

You are correct.  This is not right at all.

 

I'd really suggest the fuel procedure in Tutorial 2.  If you continue to use unrealistic fueling practices, such as using TOPCAT's estimates, or flightplanner.com (it seems this website is no longer active when I try the address), your realistic simulation of the aircraft is not going to behave how you expect it to.

 

The software dispatchers use has the exact same fuel logic that the FMC uses to calculate everything.  As such, the fuel numbers they hand the pilot are very accurate.  You can emulate this by using the FMC itself as your "dispatcher."  TOPCAT does not take into account filed altitude, wind and several other factors.  It's an estimate to give you a preliminary idea just in case you haven't run your fuel burn numbers yet.  I can't get to the web address that you mentioned, but I highly doubt it's using any sort of calculation other than rudimentary rules of thumb.

 

Tutorial 2 describes how to get accurate fuel through utilizing the calculations right in the FMC.  This will help you better fuel and fly the aircraft.  It will also explain several other things about fuel and route/cruise planning.

 

Okay, I'll go through tutorial 2 again when I get some time.  I was just sort of hoping that I could find a 'dispatcher' so I didn't have to go through the fuel procedures in tutorial 2.  Topcat seems to act like a dispatcher but, yeah, I at least noticed that it didn't seem to know anything about winds aloft.  The website I was using is http://www.fuelplanner.com/ ...some people had mentioned it here.  I don't think it knows about winds or cruising altitude either.

 

 

I was just sort of hoping that I could find a 'dispatcher' so I didn't have to go through the fuel procedures in tutorial 2.

 

Once you get the hang of them, it's actually pretty quick.  You have to enter the route anyway, so that time isn't lost for the fuel planning only.  It's just a matter of breaking the "bad habit," if you will.

 

 

 

The website I was using is http://www.fuelplanner.com/ ...some people had mentioned it here.  I don't think it knows about winds or cruising altitude either.

 

Ouch, yeah.  It doesn't know weight, altitude, winds aloft, or anything.  It's a nifty tool for your average simmer flying the default stuff, but it's nowhere near as realistic as it should be for other purposes.

 

(turns out I was just omitting the www. in the address earlier)

What am I doing wrong here? 

 

...

 

I load up 13000 lbs, put 6.0 in the plan fuel

There's your problem. You're likely misunderstanding the function of the PLAN/FUEL configuration item (next to the 2L LSK on the PERF INIT page). Its intended use is allowing you to input an expected total amount of fuel on board before that fuel has actually been loaded. It is not used to indicate the estimated amount of trip fuel. When in doubt, you should probably leave that field blank. See FCOMv2 page 11.40.30 for more information.