Still have that speed problem....

[paulyg123 135]

I did a test withthe 737 and compared it with the LD767:The 737 with 121, 000 lbs 15, 000 lbs fuel at 10,000 ft at 200 kts I decended at 2,000 fpm with and with speed brakes - no flaps and compared this with the 767. Here are the results:speedbrakes on10,000 ft 200 kts 737-800W 200kts 767-3009,000 ft 215 2008,000 226 2027,000 235 206.56,000 242 2105,000 248 213.54,000 252 216Clearly the 737 sinks like a lead zeppelinHere's the same wothout speed brakes deployed10,000 200kts 737 200kts 7679 222 2148 242.5 228 7 260 2406 274.5 2505 286 2584 296 264.5Even at -1,000 fpm the 737 gained 27 kts from 10,000 to 5,000 (no speedbrakes) the 767 loses speed.I am not commenting on which flight model is correct. I'll run this test in the Level D 737-800W next week and see which is believeable.

[JC75 22]

"when in doubt, level out" suspend your descent until you slow to a manageable speed, then hold that speed with appropriate flaps/gear/speed brakes and you'll be surprised how fast you can descend and not gain additional airspeed.

My 2p.Just descend in LVL Change mode at 240. level out at platform altitude 5 - 10nm prior to Final Approach Fix. Flying level at idle, you sure as hell will slow down. The more it slows the more it Will slow, as the nose comes up to increase lift. As soon as you start getting flaps down the drag will begin to take over.When GS becomes active you should have, I think, (works for me) flaps 15. As it crosses the top marker on the GS scale you can take gear and flaps 25. as it crosses the lower marker you can take flaps 30. By now you will be using plenty of power to stop the speed falling off. as you hit the GS at FAF you can lower the nose to 2.5degs or whatever it is these days and throttle as required to maintain your desired speed.I do not fly 737 for a living but believe these numbers arent far off, and the work for me in the sim.One other thing, which could be causing your issue. I have to calibrate my joystick before every session. Otherwise it does not go to true idle. You can tell if this is the case if you are accelerating whilst taxiing with idle throttle.

You'd be in big trouble with your airline flying that way...you'd be being asked why you burning so much fuel, why you responsible for their airline being at the top of charts for failed CDAs...The issue is here I feel, hf4 made descent better at managing speed at higher levels, but non of the hf have improved speed/descent in the latter stages or on the approach. It's the flight idle settings at these points that still seems too high, causing speed to either not bleed off sufficiently or in some cases increase. I have setup a descent with a commanded speed of 220kts from 8000ft at a typical range I vector 738 from...speed brakes out , even tried it 210 with flaps1 and find to maintain that speed, or slow to 180kts as I come onto base is often not possible, without majorly increasing range, and an even smaller descent rate. Either way again once established flaps 10 speed set to 170, and descending with glide, speed can be seen to increase, or won't come back to 170. Gear out and flaps is only way to get it to slow down,and even that not always perfect. The sp has improved initial descent my flight idle seems lower...but seems too high once lower down in the initial and final approach stages.In the original posters pic, he does have too much fuel, and obviously too heavy...in my case I'm landing with a standard fuel reserve typical for a 738.

[davierosoft 13]

If you are flying with sp1 it is strange. It solved for me.It is strange that the same kind pf issues appear on different users and with different patches applied.I had problems in hf4, other in first release, other after Sp1. Strange.

[Paul Deemer 13]

Press the Spd Invt button above the level change button and set speed to 240 knots and see what happens then. Maybe it's not real world policy but I always manually set the speeds at 10,000 and below using Speed Intervention.

[jeffhunter 0]

In the DES page, do have the SPD RESTR set to 240/10000?

[JC75 22]

In the DES page, do have the SPD RESTR set to 240/10000?

Press the Spd Invt button above the level change button and set speed to 240 knots and see what happens then. Maybe it's not real world policy but I always manually set the speeds at 10,000 and below using Speed Intervention.

Not sure if these aimed at me or originally poster, but I'm flying in full mcp commanded speed at this point, using either lvl change or vs to descend.not vnav. The sp fixed the management of speed and descent from TOD point, far better control, and better thrust idle settings. It's the descent after this point, once on headings, and fully managed level change or vs mode, if I force throttles to keep reducing further by holding f1 then get better(although probably now too much) speed management.Pmdg said before the n1 idle levels were too high prior to sp1. So perhaps they not still been fully tweaked enough for all the stages of the flight.

[davierosoft 13]

I've not recently tried LVL chg for descend, sp1 solved my problems in VNAV, but, on the next flight I'll try also the SPD descend istead of path descend and lvl chg.

[JC75 22]

Vnav descent used down to the slp once in the stage where going to be vectored then lvl change and vs primary methods, in fact often a combination of the two, manipulated based on track miles, ATC speed requirements and in order to better achieve CDAs. This is my view where once at these kind of levels there is something wrong with the logic or parameters of the ngx which is making the aircraft faster and less able to manage speed as well as the real world would do. The sp1 as fixed the vnav descent and flight idles in that phase but not afterwards.

[bluepilot76 0]

You'd be in big trouble with your airline flying that way...you'd be being asked why you burning so much fuel, why you responsible for their airline being at the top of charts for failed CDAs...

You would be in a lot bigger trouble if your were flying uncontrolled / unstabilised approaches because you did not get your energy management right. Its basic Airmanship, fly the plane first, safely, fuel economics is secondary or in fact way down the list of priorities.If the simulated aircraft is too slippery or has too much idle thrust in the simulator then you should be able to deal with that through your piloting skills, is that not what makes it interesting?Its been a little while since I rode on a 737, but I am fairly sure it is not unreasonable to expect a level off, slow down phase around platform altitude, you are not burning extra fuel here as you are at idle, it is only as the GS comes alive that you start having to offset the drag from getting configured with more thrust.I was often advised during my IR that ATC have a habit of keeping you high. Sometimes you have to force the issue.Would you, as the controller necessarily know if the 737s are having to use drag to maintain the profiles you are prescribing? I certainly see a lot of drag use in busy areas like London, or for that matter in the procedure at my local airport.Interesting topic though, I will have to try one of these CDAs soon if thats what everyone else is doing.

[SilvioSilva 4]

Nobody talked reagrding the CI( Costing Index) data in CDU!. Is it around 20?I generaly use 27 and you? It impact the speed in all flight!

[davierosoft 13]

Nobody talked reagrding the CI( Costing Index) data in CDU!. Is it around 20?I generaly use 27 and you? It impact the speed in all flight!

I mentioned it for te same reason a page ago! :-)My values are around 30

[SilvioSilva 4]

I mentioned it for te same reason a page ago! :-)My values are around 30

Opss Sorry Daviero, Yup, you mentioned.

[davierosoft 13]

;)

[Leffe 4]

thanks for the advice, hope you guys can see it now....

Since you still are on VNAV.....look in your CDU what kind of speed youhave, before and when reaching IAP fix. VNAV should take off speed, if you have it on that long.I would instead if VNAV, intervene my speed by pressing that button on MCP, so itwill override VNAV speed. But in most cases I prefer to use LVL CH as I said earlierwhen below 10 000.As a Pilot you have to make your decission and not just rely on a FMC computer.I wouldn´t be travel with you, if you were one, if you can´t use your brain./ Leffe

[morganbass 10]

A questionDo you input your flap and approach speed in the approach page on the FMC?Wycliffe