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Guest Bpilot

An odd flight - VNAV went crazy...

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Fellow Captains,This was supposed to be just a routine flight. Here is the report:- CYEG to KSEA. Regular weight, 90X1000 lbs fuel.- Head winds 16, gusting to 21.- Targetted altitude, FL 360; VNAV page two stated OPT 367/MAX 409.- At beginning of climb, the whale was "bouncing" up and down most of the time (wind?).- After getting to FL 220 using VNAV, the VS rate was minimum. No way I could climb faster. ATC started complaining...- Worst, speed did not increase: stayed around 280 (target 315).- After a while, I tried VS at 1200 ft/m and disconnect VNAV. Climb finally started and reached FL 320, but speed decreased to a point of danger. Level at FL 320 hoping to pick up speed; no way. Always at the margin (red dots).- Back to VNAV; targeted a new speed in VNAV climb page (.0830 instead of targetted .0854). No deal...Still loosing speed.- Went down to FL 300, hoping to pick up some speed. No way.- The B was still "bouncing" up and down all the time.- I tried mannual throttle (left A/T armed) and pressed F4 to the max fo a few seconds;- The throttle RPM went red and announced...- Than speed went below the red zone: Gosh! What a horrible noise!!- Turned off A/T. Tried again max throttle for a few seconds, in spite of red RPM. Got some speed to clear up the red zone.- At this point was called to start descent... Turned on A/T but rate of descent was very poor (about 250 ft/m);- Went back to VS and than... SPEED WENT OVER! Back to the red zone, this time upper...- Managing the throttle and VS - VNAV was not working at all - and after a three loop hold in PAE, I managed to land.In sintesys, a terrible flight...And here are the questions:1 - What prompted that difficulty in the initial climb? I do this flight quite often, same airplane, payload and gas.2 - If A/T is disconnected, it appears it does not catch back: is it true?3 - Why the airplane does not pick up speed when descending with VNAV?Gents, I have some quite good hours with the whale, but this was a first.I'll try again today, but please comment on this flight.BPilot

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Oddly enough, almost this precise behavior occurred to me just recently... wickedly frustrating, isn't it? :(In my case, what I believe triggered this: I loaded a flight which I had saved _prior_ to upgrading the Queen to the latest patch...- Bill

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Sam,Thank you for your detailed reply. I'll take some time to diggest it, but "to leave is to learn"...Anyhow, I tried Bill's suggestion - ie, re-do the flight plan and save with the new Queen. Oddly enough, it worked without a flaw. Just as before...Keep the blue side up!BPilot

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That tech stuff's fun to play with too, but sometimes it's just a computer (my own) thing. Took a flight from LAX to PHNL yesterday and got totally blasted by winds. AS and ROC were a wild ride. Got a tip to delete FSUIPC.ini and let it rebuild. Settled the winds right down. (The latest version has "smoothing") Also had FSUIPC joystick button programming problems and it finally let me re-progrm my stick buttons successfully. Glad to hear it's working. Mine too, finally.

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