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Guest nattydread

What is the standard or expected decent rate for 737s and jets in general

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Guest nattydread

When descending from cruise(from T/D or when instructed by ATC) to the approach/terminal area what is the usual rate of descent?Is 2500ft/min or even 3000ft/min too much?Is it better to think of this in terms of ft/nm, if so what should it be?

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>Is 2500ft/min or even 3000ft/min too much?I don't think these are excessive figures. Pilots want to be nice to passengers and not to overspeed - primary two considerations for picking a descent rate.Bear in mind that in todays world rarely would an airliner descend from its cruise directly to the terminal area. The descent would normally involve some step-downs (in other words temporay level-offs) - specially true when descending to big metropolitan airports.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2

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Guest nattydread

I assumed there would be step-downs, but I also assumed that the descent rates for these step downs would be roughly the same until reaching the terminal area. I them assumed the descent rates for the terminal area would be less.What would be considered too much? Out of fear once I tried 4,500ft/min. I had some over speed problems, but I'm new to the 737 and wasnt yet familiar with how the plane would react...I think I could have pulled it off had I been flying full manual and had cut the engines and slowed before my descent.

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Guest EISN_CONTROL

You should be using the FMC to calculate the descent rate or using Level Change to specify the descent rate needed.I've seen pictures of Airliners climbing/descending at 6000ft/min.Not really a big deal at all.John http://homepage.eircom.net/~eamonnmca/images/logo_ba.JPGwww.bavirtual.co.uk Senior Captain Simflight.com Staff Reviewer

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Don't forget the forecast page as well!!! This is of utmost importance to get your ROD right. You are required to enter winds at various altitudes on your descent to ensure you limit overspeed disconnects, or overshooting your descent path.Most commercial pilots will use either VNAV descent or SPEED descent, unless advised otherwise by ATC. Even then the FMC can be programed for just about anything.

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I generally use about 1700 ft/min, but as MSFS's ATC is somewhat funky, I make up my own VNAV procedure based on STARS if available for the airport. Most STARS have a note that indicates a waypoint with the statement: "For planning purposes turbojets should expect to cross as xx,xxx ft and at xxx kts". I work backward from that point and calculate how long a 1700ft/min descent will take to get there. I then request an altitude decrease from ATC at the appropriate point; rule of thumb: about 130nm from the destination. All this planning gives me something to do while in cruise and keeps me focused on flying. ;-) Mike

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>>What would be considered too much? Out of fear once I tried>4,500ft/min. You can see how different descent rates 'feel' by using your simulator.As for 'nominal' descent rates here are some numbers (rounded) that come from some professional software that simulates 737s:At 5000 ft 1400 ft/minAt 10000 ft 1500 ft/minAt 20000 ft 2000 ft/minAt 30000 ft 2600 ft/min Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2

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Guest nattydread

Now thats what Im talking about!!THX

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Guest nattydread

Its great that the FMC can calculate ROD when you are allowed to follow your STAR as published, but when ATC takes you off your STAR and begins vectoring you and stepping you down on its own, it becomes a good idea to have some estimate on how fast they want you to get down. For instance, my flight plan had me using a STAR for one runway, but ATC had reversed the runways, so now my STAR was useless and ATC wasnt going to issue me another. Now Im at the mercy of ATC with no detailed idea of how they plan to get on the FAC. No problem, I can hand fly this bird so Im not dependent on the FMC or MCP, I just need to make sure Im getting down on time for whatever ATC is is trying to get me to do.

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Charles,experienced ATC will advise you on your next expected altitude and decend you if they are vectoring you.

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Guest nattydread

FS9 ATC certainly doesnt act like experienced ATC...though NorCal Approach doesnt do that for me in real life either :)

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