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SPEED + V/S after take-off

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Guest matchouz

Hello... I'm brand new with the PMDG 737NJ. I've read a couple of tutorials before deciding to post a message on this forum. Well... I've managed to get myself in the air quite well (first step. Now comes adding holds, flying to a given waypoint, etc...) My problem is as follows... Soon after i take off, and whenever i want to catch my planned course, i turn on LNAV and VNAV. The problem is that the plane seems to be climbing at an exagerated rate (4000/5000 or so...) and the airplane doesn't seem to reduce the speed to 250 kts as i specified on the FMC (n1 limits). If i select N1 on the auto-pilot, other functions such as VNAV or LNAV disconect, which is not quite useful. Hence, what i'm trying to find out is how to have a correct rate of climb and how to respect speed restrictions... Thanks for the help...CheersMat

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N1 limits do not protect airspeed restrictions, just the engines.A lightly loaded 737 will leap into the air and climb like a bat out of ####. I assume you turn on LNAV VNAV and A/P along with A/T and FD. When all is as it should be, the FMC should let it accelerate to 250 and then hold that up to 10,000 (US) with full CMB power. Above 10,000 she will lower the nose and accelerate to whatever the computed climb speed is as shown on the CMB page.One thing I can't tell from you note is how fast you're going when you engage A/P? Normally, you should be at about V2+10 and in the process of raising flaps on schedule. If you are light, it is very hard to hold V2+10... try derating your takeoff power CMB2 or CMB3 for example (setup on TAKEOFF page during preflight).Hope this helps.


Dan Downs KCRP

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>Hello...>> I'm brand new with the PMDG 737NJ. I've read a couple of>tutorials before deciding to post a message on this forum.>Well... I've managed to get myself in the air quite well>(first step. Now comes adding holds, flying to a given>waypoint, etc...)>> My problem is as follows... Soon after i take off, and>whenever i want to catch my planned course, i turn on LNAV and>VNAV. The problem is that the plane seems to be climbing at an>exagerated rate (4000/5000 or so...) and the airplane doesn't>seem to reduce the speed to 250 kts as i specified on the FMC>(n1 limits). If i select N1 on the auto-pilot, other functions>such as VNAV or LNAV disconect, which is not quite useful.>Hence, what i'm trying to find out is how to have a correct>rate of climb and how to respect speed restrictions...>> Thanks for the help...>>Cheers>>Mat What version are you using? On the CLIMB PAGE there should be a speed restriction of 250/10000. In VNAV the plane will keep this speed if you actually have the A/P engaged. Make sure you have selected the A/P in CMD. ROC is nothing to be concerned about. It is quite normal and realistic to climb at such rates at lower weights. You could select LVL CH with a speed selected on the MCP too in HDG.Best,Randy J. Smith

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Guest matchouz

Randy and Dan... Thanks alot for all the help... I think i'm doing better... with the training, i hope everything will come along fine... Dan, are you telling me that it is normal for such plane to climb up to around 3000 feet per minute (at times) while under 10000ft? Also, something i reminded i wanted to ask, the answer to which i din't find in any tutorial... (sorry if it is no longer in relation with the subject of my first few questions...) 1) Are there any "DIRECT TO" function in the FMC? a. What if i want to jump one waypoint? b. What if the ATC asks me to fly to a given VOR or waypoint? How can i insert it in the actual flight plan and fly to it, with the possibility to return to the normal flight plan afterwards? 2) It is sometimes quite annoying to have to fill in the same flight plan many times. is there a way to save them on the fmc?Thanks again for your answers...cheersMat

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> Thanks alot for all the help... I think i'm doing better...>with the training, i hope everything will come along fine...Air Transport Rating requires 2000 hrs.. that's just to be considered.>Dan, are you telling me that it is normal for such plane to>climb up to around 3000 feet per minute (at times) while under>10000ft? Absolutely.> 1) Are there any "DIRECT TO" function in the FMC? Not exactly like the Garmin... you can direct to a fix by entering in the top line of the LEGS page.> a. What if i want to jump one waypoint?Press the Left Side Button (LSB) next to the fix you want to go to on the LEGS page, then "promote" it to the top line by pressing the top LSB, don't forget the EXEC button to make the change> b. What if the ATC asks me to fly to a given VOR or>waypoint? How can i insert it in the actual flight plan and>fly to it, with the possibility to return to the normal flight>plan afterwards?Again, using the scratchpad line and LSB on LEGS page.> 2) It is sometimes quite annoying to have to fill in the>same flight plan many times. is there a way to save them on>the fmc?Once the plan is entered and executed, a SAVE line will appear on the 1st ROUTE page. Press it, plan is saved. Better read the manual that came with the plane.. it provides the answer to how to load a plan you have saved, and much of the above information as well.The manuals are really really important.


Dan Downs KCRP

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Guest matchouz

Thanks alot for the help, it was really fruitful... I will read more of the manuals... See you in the skiesMat

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