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chumley

Early levelling

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Over a number of months now I have found that the 737-700 and 737-800 have a tendency to level out early incurring the wrath of ATC. The only way to get them to continue climb is by manually setting a rate of climb Vert Speed in the autopilot.Invariably this premature levelling occurs around FL270 - FL310. Weight is not an issue. I have used both Vnav and the other Lvl Chg options with no success.Andy suggestions?Andy b

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Andy,Never had a problem with this unless my weight was up the roof. But you say that this is not the issue here... What's your pressure and temp when this is happening?Could be a level out due to altitude constraints on waypoints in the route.Is this an intentional level-out from the automation? I.e. do you get the pre-level aural warning (MCP) before the level-out, or does the FMC revert to CRZ mode?Can you supply us with a screenshot of relevant parts when this occurs? Sorry I can't be of more help than asking more questions ;-)

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>Over a number of months now I have found that the 737-700 and>737-800 have a tendency to level out early incurring the wrath>of ATC. The only way to get them to continue climb is by>manually setting a rate of climb Vert Speed in the autopilot.>>Invariably this premature levelling occurs around FL270 ->FL310. Weight is not an issue. I have used both Vnav and the>other Lvl Chg options with no success.>>Andy suggestions?>>Andy bAndy,Make sure the MCP ALT and the FMC CRZ ALT are the same and there are no ALT CONSTRAINTS on the LEGS page during the climb.Floyd

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>Andy,>>Never had a problem with this unless my weight was up the>roof. But you say that this is not the issue here... What's>your pressure and temp when this is happening?STD pressure - temp unknown>>Could be a level out due to altitude constraints on waypoints>in the route.No, only altitude constraint is cruise>>Is this an intentional level-out from the automation? I.e. do>you get the pre-level aural warning (MCP) before the>level-out, or does the FMC revert to CRZ mode?Occasionall the level out occurs immediately the aural warning is heard. From memory I don't think it has gone to CRZ mode but I could be wrong.The aircraft simply dies in the climb - possibly related to a sudden windshift and consequent loss of airspeed. However, it does not pick up again after the airspeed has reached the desired level.>>Can you supply us with a screenshot of relevant parts when>this occurs? Will continue to monitor and take a shot of the panel plus fmc when I can>>Sorry I can't be of more help than asking more questions ;-)Thanks for your questions - I will watch more closely. I'm sure it is I that is simply a crap pilot. I'll read the Metzinger tutorial and apply the actions to my flights.RegardsAndy b

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>Andy,>>Make sure the MCP ALT and the FMC CRZ ALT are the same and>there are no ALT CONSTRAINTS on the LEGS page during the>climb.>>FloydDone both of those but thanks for the suggestions.RgdsAndy b

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Occasionall the level out occurs immediately the aural warning is heard. Andy this will only happen if the conditions are met, in other words the MCP will be set to the leveling off altitude OR it has captured an altitude pre programed in the route. The aircraft will never just level off on it's own.Best Wishes,[h4]Randy J. Smith[/h4]http://www.rawbw.com/~bdoolin/shinault/southparkcartmad.gif[h3]PMDG 747![/h3]Caution! Not a real pilot, but do play one on TV ;-)ASUS KV8 DLX | AMD 3200 64 | 1 GIG PC 3200 DDR | GIGABYTE 5700 ULTRA | ViewSonic VP192b 19" |

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Andy - Randy took the words out of my mouth. If you hear the aural pre-level warning you must have the MCP set to that altitude. There is no other way you can hear it otherwise. The pre-level warning is connected to your MCP speed and nothing else.Hope it helps

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>The pre-level warning is connected to your MCP speed and nothing else.The above should read:The pre-level warning is connected to your MCP altitude and nothing else.And nothing else! ;-)TGIF, :-beerchug

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>Andy - >>Randy took the words out of my mouth. If you hear the aural>pre-level warning you must have the MCP set to that altitude.>There is no other way you can hear it otherwise. The pre-level>warning is connected to your MCP speed and nothing else.>>Hope it helpsI understand that Mats, but what I was trying to say was that it levels immediately the aural warning is heard - some 7-800 feet below the altitude set on the MCP - and does not finish the climb.As I said I suspect it is something to do with aircraft velocity following a wind shift or a heavy load has caused deceleration. I am continuing to monitor to get a handle on this.Thanks againAndy b

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Ahhhh... I see!I thought it was a level off way off the target altitude. ;-)Please post any findings of your monitoring here. Cheers, :-beerchug

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Randy and MatsAfter a number of flights I think I have the measure of this bird.I now use VNAV to accelerate to 250 knots and then LVL CHG for the climb after that to 10,000. I then switch to VNAV to accelerate to 315 knots and once again back the LVL CHG until swititching to VNAV just prior to reaching cruise. This maintains an acceptable climb rate in all cases without compromising airspeed. I'm also now flying with Radar Contact and they are not continually tweeking my balls to make me achieve altitude at their pace. The only problem I now have is the carpeting I get at the end of each flight for not responding to each radio call immediately and a couple of visits from Bill Stevens.Thanks for your help guys. Never did think it was the bird.RegardsAndy b

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