It's been mentioned in a preovius post, but i need you tohelp out with a problem i and some others have!after takeoff pushing the VNAV, it no longer holds the flapspeeds shown on the PFD, but accelerates to 250 KIASwithout holding the speed at 5 degree flap setting, if you knowwhat i mean! When you takeoff and push VNAV on, the VNAV is supposed tohold the speed for flaps until you retract them up!Theese flap speeds are shown on the PFD just like the takeoff speeds(V1, Vr and V2) and before the 800/900 came outthis speed holding was working fine!Try finding the post by Lee Holland and read if you don't understand me here (i'm not good at explaining problems like this)

Aren't the green markings reminders telling you to retract flaps ?Cheers,Ian Udingahttp://www.precisionmanuals.com/images/forum/800driver.jpg

yes, it shows recommended speed for retracting but alsothe manouverability for the aircraft at the certain flap setting!which means VNAV is to hold theese speeds and notspeed to 250 KIAS before you retract the flaps!It's just that this was working before the 800/900 came out!

Are you sure you're not confusing this with the Airbus?The A/T will maintain the N1 limit at takeoff with the A/P controlling pitch to maintain V2+20. When you select VNAV, this will take you to your selected FMS speed below 10,000 ft. and it's up to the flight crew to retract the flaps on schedule. The A/T and A/P will fly the airplane to the commanded bug speed and the bug will not stop at the flap retraction or manouvering speeds without aircrew intervention.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.precisionmanuals.com/images/forum/ng_driver.jpg

Norwegian, Where is your PROOF? Just because it was this way on the 600-700 does not always mean it was correct behaviour! So please insted of just stating something as factual provide some facts like AOMS etc, opinions do not mean anything sir..[h4]Best Wishes,Randy J. Smithhttp://www.precisionmanuals.com/images/forum/betaimg.jpgAMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | WD SATA 80 GIG | 512 DDR 400 |

I don't want to add to the ire below, but I took my first flight in the 900 last night and indeed my aircraft did hold at 249 KIAs until I realized I was still at Flaps 1. Once I raised them from the throttle panel the plane accelerated up to cruise speed. Will have to check this on my 800 also. So Norwegian, it would seem there is something going on here."It's been mentioned in a preovius post, but i need you tohelp out with a problem i and some others have!after takeoff pushing the VNAV, it no longer holds the flapspeeds shown on the PFD, but accelerates to 250 KIASwithout holding the speed at 5 degree flap setting, if you knowwhat i mean! When you takeoff and push VNAV on, the VNAV is supposed tohold the speed for flaps until you retract them up!Theese flap speeds are shown on the PFD just like the takeoff speeds(V1, Vr and V2) and before the 800/900 came outthis speed holding was working fine!">>Norwegian,>> Where is your PROOF? Just because it was this way on the>600-700 does not always mean it was correct behaviour! So>please insted of just stating something as factual provide>some facts like AOMS etc, opinions do not mean anything sir..>>>[h4]Best Wishes,>Randy J. Smith>http://www.precisionmanuals.com/images/forum/betaimg.jpg>>AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA>@535/1000 | WD SATA 80 GIG | 512 DDR 400 |

Randy,Try a search for Command Speed Limiting. Does that refer to it?Back to the buses.:)RegardsHoward Isaacs

The PMDG guys got it right. Pushing VNAV above 400 feet RA will send the airspeed bug to 250kts. Thats right.It is not a standard takeoff technique to engaged VNAV just after takeoff and when the flaps are still down even though it can be done.Boeing says to engage VNAV above 3000 feet mainly so you don't exceed flap speeds (could takeoff with flaps 15) and don't bust Class D airspace speed limits.You former PIC and 744 drivers need to learn the proper takeoff technique when flying the NG.Very happy with this product. Good Job PMDG!Floyd

It is not a standard takeoff technique to engaged VNAV just after "takeoff and when the flaps are still down even though it can be done"I disagree, we do it on the 300 series all the time, in fact it is the preferred method for our company purely because it provides a limit speed for each flap setting!! I watched it happen oday coming out of Alicante in SPain, we were levelling off at 4000 initially and the aircraft was in ALT ACQ ,the speed built quickly and we were at 201kt with flap 1 when the PF called FLap zero. With flap 1 the commanded bug speed was 220kt which the A/P was aiming for. As soon as all the dangly bits were in and the lights out the bug motored to 250kt as per the below FL100 restriction. So the question is if it happens on the 300 why not on the NG? OR indeed is there a problem with the PMDG VNAV mode. I am not saying there is a problem just that the VNAV mode on the 3/4/500 series does provide protection for flap settings in the take-off / initial climb phase! I haven't done the NG differences course yet so I am not up on the specifics so a real NG driver might want to chime in on this. RegardsKris

I just got this confirmed by our 800 driver today so everyone listen up ;-) Selection of VNAV pior to flap retraction in TO mode will cause the speed bug to go straight to the airport restriction (i.e. 250 under 10000'). It will NOT keep the flap settings on the climb page whatsoever. [h4]Best Wishes,Randy J. Smithhttp://www.precisionmanuals.com/images/forum/betaimg.jpgAMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | WD SATA 80 GIG | 512 DDR 400 |

Kris,Your right We really need to compare a real NG with the PMDG NG, not a 15 year old -300. Floyd

FloydI'm not sure what knowledge level you have in the real world scheme of things so I'm not quite sure how to take your remark. The 3/4/500 was designed 15 years ago but they were still rolling off the production line with update 10 FMC's not 5 years ago so they aren't that out of date. Also the 300 type rating actualy includes the NG as well, I am rated to fly 300 - 900 series aircraft. the only restiction to this is that I need a 1 day differences course. I discussed the differences at length with the GECAT instructors and they were of the opinion that anything the 300 does the NG will do particularly when it comes to safety, I will verify the fact about the flap restriction on the VNAV mode with a few NG drivers I know. It may be that this is an option that some airlines took and others didn't.In the mean time this is from the Boeing B737 Operations manual:P11.31.18 bullet 2"VNAV EngagementVNAV commands an airspeed increase to the planned climb speed profile, limited by configuration."Also from our company ops manual SOP - 17 para 6.6.3"... selection of VNAV will drive the speed bug to the climb speed of 250knots. Whilst the aircraft will accellerate, speed intervention will ensure that flap limiting speeds will not be exceeded."Yes, again I agree that this is for the 3/4/500 series but I knwo that speed intervention systems for flap retraction has not been removed from the NG!Hope that clears some of this can of worms upKris

First, I'm not a real pilot... not even friends with one.I just thought I would contribute the following excerpts from an AOM I have for an airline that fly the 3/5/7/8/900 series.http://forums.avsim.net/user_files/74710.jpghttp://forums.avsim.net/user_files/74711.jpghttp://forums.avsim.net/user_files/74712.jpg

Any updates Kris?

Yes here's the definitive answer, which makes us all sound a bit foolish but here goes:VNAV Will indeed drive the bug to 250 kt regardless of flap position when engaged!BUT!!The VNAV speed protection will not allow the aircraft to accellerate beyond any limiting speed so if there is a limitation due to flap being extended then it will not bust that flap limit speed. The bug will not drive to the flap limit speed in other words but it will stop accellerating if it senses that there is a speed restriction due to configuration.Hope that clears it up.Kris