FMC speed restriction/flaps and autopilot/single channel

[Guest ph-ndr]

Thanks for a great product and a nice upgrade :)I had it out for a few spins today, doing my usual hopping on the norwegian west coast. On a short hop from ENZV to ENBR I caught two bugs, have a look at the URLs for the pics:ihatent.com/~alexh/app-channel.PNGihatent.com/~alexh/speed-flaps.jpgFirst one is wierd, the display says "single channel" and both channels are clearly engaged, yet it would still capture g/s, and execute the flare. Toggling the channels on/off did not help.Second one was during climbout from ENZV, where it would not remove the flap 1 speed restriction even though flaps are clearly retracted. Only way to get this cleared up was to toggle CLB mode from "angle" to "rate" and back.A minor niggle, why is the font in the FMC so big? I loved it the way it was in the -700 1.3 version.ttfn,Alexander Hoogerhuis

[crvm 0]

You MUST remove those pictures please! I will answer you questions since I have DSL to have veiwed them lol.1] There is no issue there since the REAL NG does not kick in the second AP until UNDER 1500 RA! It will ARM when you PUSH the second CMD, the FMA is what is important and it's 110% correct in this respect. Please look at a real AOM if in doubt sir!EDIT:2] Ok something there is strange, did you select SPD INTV prior to flaps retraction? [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 |

[Guest ph-ndr]

Thanks for the quick reply, but something is different:1. If the real NG doesnt kick in the second AP untill under 1500 RA, then why does the 600/700 do it in v1.3? I fly this jump often in the 600/700 and I routinely with the autopilot to app-mode and two channels as I intercept the g/s during this turn.2. Eh, look again. I'm have flap 0, I've had my flaps up for some time (close to two mins judging by the climb rate, it was an almost empty flight). Then why is the FMC still insisting on keeping a speed restriction at 190 kts, when I do not have flaps deployed? I am aware that I did override the speed restriction, to avoid climbing out at 190kts in a clean configuration, which at max angle should pan out to about 225 kts or so? And why are you mentioning flap 5, that was in the other picture, during the approach which happend about 20 mins later :)

[crvm 0]

1] Because it was WRONG! In fact I made it a personal quest to get that corrected! 2] I do not know what you are pushing but I do know that regardless of what is on the PAGE that you are in MANUAL speed control with SPD INTV. Now the real questions should be this" Why is the VNAV flaps restriction speed still on the CLIMB page after flaps are up?" To be honest there should not be any flaps restrictions since flaps 5 maximum speed is 250 knots![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 |

[crvm 0]

Please view the wording here sir since you are in doubt about SINGLE CH staying until 1500 RA even though the second CMD is selected and or G/S is already active. This should settle it ;-)http://forums.avsim.net/user_files/73047.jpg[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 |

[Guest ph-ndr]

1. Well that clears that out, new way of life learned and it wasn't a bug in 800/900 :)2. I know I'm in SPD INTV, forget that, the issue is indeed why there is a speed restriction showing on a clean climb. And that, is wrong. I haven't driven the real thing, but I'm feelin pretty confident that one classifies as a bug.I did not press anything special to get to that point, it was a prety normal takeoff for a light load (toga, nose up, gear up, retract on schedule).:)

[crvm 0]

Yes it should not be there with flaps retraction. I believe it should not be there at all or at least disply the true limit of 250 knots for flaps 5. My point about SPD INTV is to say that your selection of it has something to do with why the restrictions did not vansih (they should have) so knowing WHY is important to fixing it ;-)[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 |

[Guest ph-ndr]

Nonononono :)I selected SPD INTV *AFTER* passing FL10 (ta 7000) because the restriction did not go away after flaps retraction.After rotation, positive climb rate and gear up I immediately started flap retraction, and in the case of an empty 900 (10000 lbs fuel, no payload). In this case I went from flap 5 (takeoff) to flap rapidly as acceleration is swift. This means I was gear up and in a clean config somewhere around 1.000-1.500 ft above the runway.At this point the restriction was still in place. Have a look at the pic. The pic shows flap 0. The FMC shows a restriction of 190/FLAPS. To have that kind of restriction you'd need flaps 25. As I had a clean aircraft I then hit LNAV/VNAV and watched it climb to around 11000 feet, and then noticed I pretty well pitched up and noticed I only had about 190kts of speed and that the speed bug was set to 190 kts. I then opened the FMC and saw I had a restrition to 190 due to flaps, which seemed odd. I then extended flap 1 and retracted, no change to the speed restriction in the FMC, and I then proceeded with SPD INTV to get to somewhere close to max angle climb rate. At that point I took the snapshot. Thus, the restriction was there all along, and 190kts is the restriction for flap 25. It was not caused by the intial flap setting during takeoff, as I used flap 5. I did not do anything unusual (rotate, clean up, LNAV/VNAV). :)I also let the aircraft climb with the 190 kts restriction untill 10000 feet, to make sure it wasn't confused about that.

[Qavion 19]

Unless, of course, you are flying an aircraft which doesn't have this option ;-)E.g. Our airline has ones which do annunciate this... and others, our latest 737-800's, which don't.The annunciation disappears 10 seconds after 1500' RA according to the Boeing Maintenance Manual (which is never wrong :()).Cheers.Ian.

[Guest amerton]

Alexander,From what I see the FMC thinks there is a speed restriction upstream (RSY?) *lower* than clean config min maneuvering speed, so it is not allowing the target.Ideas ?anthonyAnthony MertonPrecision Manuals Developmenthttp://www.precisionmanuals.com

[Guest ph-ndr]

Sorry, there is no restriction going out that way, only restriction on that one is somewhere on the LUCKY STAR into ENBR. And if RSY had a restriction, should that not have said "190/RSY"? :)I'll hop into the machien again and redo it, and see if I can trigger more funnies too; I had another snag on that flight which I didn't capture, it had CRZ speed set to 0.6M (in VNAV/LNAV) and on using DES NOW it did a speedup to 0.76M, which I'm sure was hillarious for the people in the back :)

[Guest amerton]

>Sorry, there is no restriction going out that way, only>restriction on that one is somewhere on the LUCKY STAR into>ENBR. And if RSY had a restriction, should that not have said>"190/RSY"? :)Not if the restriction is lower than min maneuvering speed for current flaps config. You'd get the XXX/FLAPS indication.>I'll hop into the machien again and redo it, and see if I can>trigger more funnies too; I had another snag on that flight>which I didn't capture, it had CRZ speed set to 0.6M (in>VNAV/LNAV) and on using DES NOW it did a speedup to 0.76M,>which I'm sure was hillarious for the people in the back :)0.76 must have been your target on the DES page ?anthonyAnthony MertonPrecision Manuals Developmenthttp://www.precisionmanuals.com