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Guest ben_eddt

Airspeed increasing with more than 1.000 f/m

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Hi all,Beside of that the 737NG is the greatest airliner existing for MSI have noticed that the 737-800 and 900 is getting faster and faster while descending with more than 1.000 feet / minute -> that

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Hi Ben,Please be more specific. What aircraft config are you in? what is teh IAS/Mach? What FMA annunciations and FMC setup do you have please?Tks,

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Yeah I created the same category topic here today lol.

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I tend to agree that slowing down in the arrival terminal area is a problem. I did read here that the PMDG 800 and 900 aircraft are very slick and resemble the real thing, however it's hard to believe that the real airplanes were designed to have to extend the gear and raise the speed brakes as standard operating practice to descend and keep under the speed resrictions below 10,000 feet. I use the Radar Control program and it's true, it is hard to descend more than 1000 fpm without hanging everything out to comply with instructions.Rich Rossler

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It's a common fact that the Boeing NG isn't a in more detail and in advance to avoid excessive speeds. We all have to say thank you to the Boeing team which made the aircraft very performant in real-life and thank you to PMDG for their excellent simulation of the aerodynamics of this wonderful plane. But this performance-advantages have some nasty side-effects like high speeds during descending (if you don't plan). When reading different fora on the real-life use of the Boeing NG, I often read the same question: "are the high speeds normal" and always the answer is "yes, it is normal and to avoid them, you have to plan in more detail and start your descend on time". Unfortunately, the FMC is not always the perfect help to the average flightsimmer to solve this problem :) I think we are spoiled with the bad aerodynamics which are standard for FS and don't require us to think about descend, the aircraft will slow down and come down without real planning,... well with PMDG it belongs to the past... Welcome to the world of more realism... ;-)

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Hi Guys,Managing the DES is probably the hardest thing about flying a jet.. that and the very accurate pitch control you need to use for approaches etc.The FMC is an excellent aid and as such can be relied upon to provide good info if you set it up correctly. For a DES the ideal or most economic DES PATH is determined to be from a top of descent point such that you can glide all the way to a landing. It is not always possible to have a continuous descent available due to traffic, ATC requirements etc but that is what we try an achieve and ATC do their best to help us out.As a starting point, if there were no restrictions on speed or alt then the VNAV PTH would take us all the way to the runway with thrust at flight idle and we would only reduce speed from the commanded DES speed (by default in an -800 it is around 265KTS but that is a little slow for most ATC so we crank it up to 300KTS as a rule) when it can do so at flight idle to arrive at 1000' AFE on a 3 degree approach path and at the landing flap setting. We do this IRL using VNAV all the way and selecting flaps when commanded by the FMC as shown on DES page. It works a treat but unfortunately it is rare to get an uninterrupted DES.So a normal, flight idle VNAV PTH Des is about 2000fpm at 300kts.. incidentally about what LVL CHG will give you as well.We like to fly teh aeroplane as fast as we can and try to do so at every opportunity. So speeds of 300kts are not uncommon even down to 1000' and then a level deceleration and extending flaps on the schedule is what we enjoy most ;)Hope this helps,

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