FMC wont engage enroute

[Guest venquessa]

I am flying from KSFO to KSAN in the 700. Route..RWY28R - EUGEN5 - BSR - J501 - RZS - J126 - LAX - SHAMU1 - SARGS - RWY09 (KSAN)I flew the Eugen5 departure with the MCP and VORs etc. Holding 7000ft until cleared to climb. Apart from the fact the BSR VOR does not have the correct range, FS2004 problem I know, all was ok. I engaged VNAV and the plane accelerated and climbed for cruise.At BIG SUR (BSR) I tried to engage the LNAV, but all I could get was "NOT ON INTERCEPT HEADING" even though I was actually perfectly on the purple line on the plan.I tried flying off to one side and intercept back onto the line and got the same error.Then I tried a direct routing, but it gave me the direct routing to the next waypoint, from the first, which was still the waypoint just after takeoff, which therefore created a flight plan that was way out.I tried lots of things, but basically the problem was the waypoints I had overflown while not in LNAV mode where still in the FMC and I couldn't even delete the first one.So I had to fly the rest of the flight on VORs. This is the second time this has happened, when I fly the departure, even staying near perfect on the purple line through out, the FMC doesn't update my position.These are screenshots showing the problem.1. Not intercepting the planned course.http://campbell-multimedia.co.uk/temp/fmc2.jpg2. VERY strange DTG's on the prog page.http://campbell-multimedia.co.uk/temp/fmc1.jpgAny ideas?Basically what I want to do is, to fly the SIDs and STARs manually, but have hte option to switch over to the FMC later.If there anyway to set the active waypoint?Thanks for your help.Paul

[crvm 0]

What version are you flying? Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

[Guest venquessa]

Emm.. 737 700 1.3 (no 800/900 upgrade).SU10 (U10.4)AIRAC 0407Thanks.I'm about to continue, KSAN to KDEN, so I'll keep an eye on the FMC during departure see if I can't figure out how to unstick it.

[Guest venquessa]

Well.. on that flight all went well, the only change I made was clicking FMC LNAV on a few times durning departure and it from then on, canceled out waypoints I passed and picked up the autopilot nicely after the SID was over.Might have been a glitch just.Paul

[crvm 0]

Tough one Paul. I at first thought that since you were following the correct hdg but were off the path a bit with the wind blowing you that the FMS correctly told you that at your current hdg you are not on an *intercept* for LNAV to enage. So it must cross the original path and be within 3 NM for LNAV to engage. Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

[Guest Buck Bolduc]

I used FSbuild to generate a FP from KMIA to KJFK. I didn't pay attension to the landing runway. After being airborn for a time I realised what I really wanted was to land on RWY 31R instead of landing downwind. I was able to delete the STAR and setup a new one with a new trans., and landed on 31R. A fine landing if I may say so myself!I should have taken the time to do it right. Had I entered 31R instead of allowinf FSBuild to desegnate a runway I'm FSBuild would have given me a better STAR or choice to begine with.I dont see what the big problem is. The FMC is like anything else. You can read the manuel to death and it gives you a start, but you dont really understand it's ideo's until you use it, more the better.Regards

[Guest venquessa]

I haven't been able to repeat my problem, yet. However I have currently got worse problems.Enroute on a max range flight, KMIA (Miami) to PANC (Anchorage), 3600nm with a forecast + safety assumption of a 30 to 40 knot headwind a lot of the way. So it will be close. :DFirst up the FMC wouldn't accept any STARs or approaches for PANC (PROGRAM ERROR) and so VNAV would not engage (as there was no bottom of descent?). When I entered a close (to PANC) field and approach as a stand in, I got to engage VNAV and it went about climbing.When I arrived at the set FL370 the VMAV disconnected, error "UNABLE CRZ ALT", even though it was at it already. I confirmed that FL370 was in the FMC, the MCP and all the legs showed FL370. Yet VNAV disco's UNABLE CRZ ALT. Altimeter was set to 29.92 STD.Finally the PROG page shows no ETA or ATA's, plus it says 0.0 fuel from the next waypoint (about 500nm) onward. There is still 38,000lbs onboard.Anyway, I was planning on doing the descent and approach sans FMC anyway, just proper forecasts and ETAs would be nice.I'm a bit baffled, I just think it doesn't like me.Paul

[chumley 0]

The FMC is probably not cycling through the waypoints as you follow the departure procedure and when you engage LNAV (or try to) the aircraft is calculating it's intercept using waypoint number 1 which is invariably behind you. As you near completion of the departure procedure check which waypoint is next in the direction of travel, click on the adjacent LSK placing it in the scratchpad then click on LSK01 to put it in as the next waypoint then engage LNAV.Andy b