737-800 range

[Guest lenrow]

hello,I understand the high gross weight configured 737-800 has a MGTOW of 174,000. This matches our 800 so I assume the PMDG 800 is the high gross weight configured airplane. The real such 800 has a range of about 2900 nm. How come I can't plan a flight with max fuel and under gross weight from KSEA to KEWR without the insuff. fuel warning on the FMC going off? Under "progress" on the FMC the arrival fuels at Newark (2100 nm) read zero. It seems the range is much less than 2900.I've tried it with less weight, less speed, econ, high low, Long range ...nothing will get me there. What am I missing?thanks, Doug Wornell, CFII

[Ralgh 43]

I personally have flown -800s from LAX-EWR, BOS-LAX, BDL-LAX, JFK-SAN and many other transcon flights never having a fuel problem. Actually we had BOS-SEA trips a while back but I never got to fly one of those. The real plane is more than capable of your trip. I say fill the tanks and blast of for EWR. See if it doesn't figure out it can make it once you get going. In FS I flew my PSS A320 from PHX to HNL and back (2 different legs of course) with fuel to spare and my PMDG 737 seems to burn less than the Airbus. Also the 737 holds more fuel.Just do it. I dare ya.

[Guest neeraj.pendse]

Two things:1. Did you try another long flight? Maybe this one has a wrong waypoint somewhere which is causing this?2. Does the warning shows up on the grouund of right after takeoff? I have seen PMDG planes would show this warning during the high fuel flow period on takeoff.3. Did you try the 737 fuel planner? It says 37.5K lb of fuel burn if I start all heavy on the 738 ... is the FMC much different than this?Hope these pointers help.- Neeraj

[Ralgh 43]

Heck I've even had the real plane tell me we had insufficient fuel on the ground. Once airborne it started giving realistic numbers.

[zubart 5]

Some of these things may help......-Check the LEGs page for incorrect waypoints and accuracy.-Winds aloft? What is the headwind component?-Use a Cost index of 20. This close to LRC.-Cruise Altitude within 2000' of optimum altitude. Start at 2000 feet above optimum and cruise until the airplane is about 2000 feet below optimum, then climb again no more than 2000 feet above optimum.Good luck.Floyd

[Guest lenrow]

Thanks all for the good advice. I did try to plan another flight of similar distance with weather off to take the wind issue out but had the same FMC determination of inadequate gas. I also tried the cost index at 20 and played with variant FLs too. I'm gonna take Tom's advice and "just do it". We'll see if the computer doesn't change it's mind en route. thanks again,doug wornell

[Guest lenrow]

hello,Tom was right. My 737-800 FMC will show innsufficient fuel for a 2100 mile trip on the ground but once in the air it recalculates and shows plenty. thanks,doug wornell

[bsmonroe 0]

Ah - the wisdom of reading the forums before posting. I had the same question. Westjet flies 737-800s from CYVR (Vancouver) to PHNL (Honolulu) - but the FMC always screams "I can't do it" on the ground. I'll give the takeoff and be damned approach and see if we can't get some real numbers.Brian Monroe (KSHN)

[Guest airbus2]

Ive heard from -700 pilots and read somwhere (cant remember where) that during takoff and climb, because of high fuel burn etc, the FMC becomes confused and 'thinks' that the high fuel burn experienced during initial flight will be the same throughout the journey. In the cruise though the FMC should calm down and make more sense!Just takeoff, fly and if the fuel warning continues for a while look around for the nearist airport!Dave.