When I'm on approach, the 'legs' section in the FMC, has a speed of 143knots for landing, (as with all waypoints there's a speed), anyhow, usually the FMC changes the speed to the one programmed, that did happen in this flight, except with final, the FMC didnt change the speed, am I meant to change the speed in the MCP for the landing speed? note; this is before I put it into APP, so it's still in VNAV.Also, with the lags page in the FMC, the alttitude that is put next to the speed is the altitude you're meant to be at whilst passing that waypoint right? if so, why does it change as in keeps going up a few feet then down?Thanks, as usually, im confused, (such a noob)Constantine V

Hi Constantine, Please sign your full name to posts in this forum per forum rules, thanks.http://forum.avsim.net/topic/245586-you-must-sign-your-full-real-name-to-posts-to-use-this-forum-posts-without-names-will-be-deleted/You didn't mention which PMDG aircraft. The forum here has sections to each specific aircraft for future reference.The FMC will change speeds accordingly, but there are differences with each A/C. MD-11 will change your speeds for you as you drop flaps. You have to also choose a landing speed in the TO/APP page when on approach.747 also has a selection page (haven't flown her in a while but think it's the same page) that you choose your final speed, but you need to set the speeds during your approach. You set your speed and when within range of a particular flap you drop that flap and continue doing so until you're at the chosen flap/ speed configuration and then do the selected speed + 10knots normally. I would suggest doing the tutorials for either aircraft since they will point out more than anyone could type :wink:Hope this helps,

Oh okay, sorry.I have the 747-400X, thanks for the tips.Constantine Veranden.

Bump. Any other suggestions?Constantine Veranden.

Doesn't need a bump as he told you how to do it. Just set your speeds as you come in and lower flaps as they come into the range.

Yes okay, but could you please elaborate on it? Speed intervention on the MCP or what?

That was somewhat already mentioned. In the 747, there is no speed intervention in the MD-11 sense. Basically, it's up to you to adjust the speed on the MCP or program the speed over the waypoint on the FMS.Here are my rules of 747 thumb:- If you get yourself in trouble, the 747 is not going to get you back out. The AP will hold speeds and adjust as best it can to stay aloft, but it does not have the same speed protection modes that the MD-11 does, in a strictly comparitive sense.- In advance of the approach, program in the hard altitudes and speed restraints. Look on the approach chart and most of the time, you'll find a waypoint that will have a note saying "Expect to cross at 250 knots and 10,000" and perhaps more.- Down to 10,000 I leave the aircraft on VNAV and let it work out its own descent path and speeds.- Under 10,000 (or as soon as I get a speed restriction from ATC) I start to assign speeds on my own using the MCP. One of the better ways to assign speeds is to look at your speed tape and look at the flap speeds. Keep your assigned speed 10-20 knots above your flap speed (but still below the cautionary yellow zone as it slides down) and you'll be in good shape. Try to get your speed down to at most 200-225 when getting close to the final approach course. Of course, ATC may assign higher or lower depending on the situation.- On final, maintain approximately VREF+10.There is a much more detailed description in the manuals and tutorials. I do recommend reading both.If you have further questions, post 'em.Cheers,Kyle

That was somewhat already mentioned. In the 747, there is no speed intervention in the MD-11 sense. Basically, it's up to you to adjust the speed on the MCP or program the speed over the waypoint on the FMS.Here are my rules of 747 thumb:- If you get yourself in trouble, the 747 is not going to get you back out. The AP will hold speeds and adjust as best it can to stay aloft, but it does not have the same speed protection modes that the MD-11 does, in a strictly comparitive sense.- In advance of the approach, program in the hard altitudes and speed restraints. Look on the approach chart and most of the time, you'll find a waypoint that will have a note saying "Expect to cross at 250 knots and 10,000" and perhaps more.- Down to 10,000 I leave the aircraft on VNAV and let it work out its own descent path and speeds.- Under 10,000 (or as soon as I get a speed restriction from ATC) I start to assign speeds on my own using the MCP. One of the better ways to assign speeds is to look at your speed tape and look at the flap speeds. Keep your assigned speed 10-20 knots above your flap speed (but still below the cautionary yellow zone as it slides down) and you'll be in good shape. Try to get your speed down to at most 200-225 when getting close to the final approach course. Of course, ATC may assign higher or lower depending on the situation.- On final, maintain approximately VREF+10.There is a much more detailed description in the manuals and tutorials. I do recommend reading both.If you have further questions, post 'em.Cheers,Kyle

So, when your above FL 100, you leave VNAV on, it adjusts the speed for you, and under FL 100, you also leave it on, you just intervene by putting your own speeds in the MCP? or do you turn it off altogether and just use the altitude hold along with the speed?

I highly recommend the tutorials. It's not so much just to answer your question, but this type of question indicates you're missing a lot, and would really learn some great info.You leave VNAV on in most cases. It really depends on the type of approach you're flying, but even then it would be more bypassing it than shutting it off. Put your desired speed the MCP and make sure the speed button is pressed.Altitude hold? Do the tutorials, you'll learn a lot and I also recommend AOA's 747-400X DVD's (or online viewing).