EARLY CLIMB THRUST REDUCTION

[FDX706 8]

I've been having a little problem with early speed reductions after I engage autoflight to engage the autopilot? I've been selecting AUTOFLIGHT passing 400 FT RA, but as soon as I do thrust is reduced and both the IAS/MACH speed and V/S-FPA windows illuminate. This all happens before I select PROF passing 1500 ft. I hope I've explained it well.... I figure I'm doing something wrong. Thanks i advance!FDX706

[MauB 74]

I've been having a little problem with early speed reductions after I engage autoflight to engage the autopilot? I've been selecting AUTOFLIGHT passing 400 FT RA, but as soon as I do thrust is reduced and both the IAS/MACH speed and V/S-FPA windows illuminate. This all happens before I select PROF passing 1500 ft. I hope I've explained it well.... I figure I'm doing something wrong. Thanks i advance!FDX706

Same here, even when selecting PROF mode before TO. :( Thrust reduces to something about 70 N1 (MD11F - GE variation).PS.: FSX version.Mauricio Brentano

[mfrantz 45]

I've been having a little problem with early speed reductions after I engage autoflight to engage the autopilot? I've been selecting AUTOFLIGHT passing 400 FT RA, but as soon as I do thrust is reduced and both the IAS/MACH speed and V/S-FPA windows illuminate. This all happens before I select PROF passing 1500 ft. I hope I've explained it well.... I figure I'm doing something wrong. Thanks i advance!FDX706

FDX706, please sign with your real name.What do you mean by IAS/MACH V/S-FPA windows illuminate? One possible explanation: If you engage the AP while your aircraft attitude deviates a lot from what the flight director is commanding, the AP will engage in a "basic" mode which is for roll heading hold at the current heading and for pitch, depending on the current VS, either altitude hold (if VS is less than 300 ft/min) or VS at current VS rate. In both these modes thrust might reduce.To avoid this make sure that when you engage the AP the flight director bars on the PFD as centered a much as possible.

[MauB 74]

Michael, thrust reduces even without AUTOFLIGHT engage.In my last flight minutes ago, N1 goes down to 47.Mauricio Brentano

[Guest keiron]

What happens when you maintain V2 by following the FD, then push the Autoflight at your thrust reduction altitude? Which I assume is 1500ftAlso after that, what happens when you push PROF at your FR altitude. Should be about 3000ft unless you've changed this.

[Tom Allensworth 1,532]

I've been having a little problem with early speed reductions after I engage autoflight to engage the autopilot? I've been selecting AUTOFLIGHT passing 400 FT RA, but as soon as I do thrust is reduced and both the IAS/MACH speed and V/S-FPA windows illuminate. This all happens before I select PROF passing 1500 ft. I hope I've explained it well.... I figure I'm doing something wrong. Thanks i advance!FDX706

Why is the subject of this message totally IN CAPS? If this kind of thing continues, we are going to turn back on the function here that prevents that. There is no reason for ALL CAPS in the subject line.

[FDX706 8]

I agree with no caps.. it was an honest mistake and somewhat of a bad habIt on my part.... As far as everyone else, thanks for your recommendations. The MD-11 is a superb aircraft!!! I'll keep you posted and what happens with my trials. Happy Landings!!Darren Esannason "FDX 706"

[FDX706 8]

FDX706, please sign with your real name.What do you mean by IAS/MACH V/S-FPA windows illuminate? One possible explanation: If you engage the AP while your aircraft attitude deviates a lot from what the flight director is commanding, the AP will engage in a "basic" mode which is for roll heading hold at the current heading and for pitch, depending on the current VS, either altitude hold (if VS is less than 300 ft/min) or VS at current VS rate. In both these modes thrust might reduce.To avoid this make sure that when you engage the AP the flight director bars on the PFD as centered a much as possible.

Thanks I got it. Had to much deviation in attitude. Kept it centered with small corrections and all was well.Darren Esannason

[MauB 74]

Here I think its an issue with a SBKP (Viracopos) SID. I've selected another departure and everything went ok.Mauricio Brentano

[Guest Totalbeginner]

What do you have set in the ALT window or what is the first constraint on the SID. If the aircraft has accelerated past the magenta circle and it enters ALT HOLD, thrust will reduce to resume the correct speed. This is common if the aircraft is light and has a high rate of climb.Once the aircraft is clear of a possible tail strike, you must continue the rotation without delay to stop the aircraft from accelerating beyond the commanded speed.Martin Neep

[MauB 74]

What do you have set in the ALT window or what is the first constraint on the SID. If the aircraft has accelerated past the magenta circle and it enters ALT HOLD, thrust will reduce to resume the correct speed. This is common if the aircraft is light and has a high rate of climb.Once the aircraft is clear of a possible tail strike, you must continue the rotation without delay to stop the aircraft from accelerating beyond the commanded speed.Martin Neep

The first constraint is 7000ft (at or below) at GRIN position (GRIN SID) wich one I've set in the ALT window properly. The aircraft has not accelerated past the magenta line and was quite heavy (TOGW aprox. 268Kg / 590Lbs). I've always carefully follow flight director before engage AUTOFLIGHT so don't know why it occurs.Mauricio Brentano

[Guest Totalbeginner]

Well in that case, I have no idea what the problem could be. I've never had a THR RED occur before THR RED ALT.When you start the takeoff roll and A/T takes over to set takeoff power, are you pushing the power lever on your yoke all the way forward to the null zone? It could be that in clamp mode the T/L position is taking presidence?Regards,Martin

[MauB 74]

Well in that case, I have no idea what the problem could be. I've never had a THR RED occur before THR RED ALT.When you start the takeoff roll and A/T takes over to set takeoff power, are you pushing the power lever on your yoke all the way forward to the null zone? It could be that in clamp mode the T/L position is taking presidence?Regards,Martin

I dont't have any power lever hardware, so think its not the case.But fortunately I'm not experiencing this problem anymore. I've edited the SID, cause it was a little outdated and the problem was apparently resolved. :( I had no more such occurrence.Anyway, thank you. :(

[Mudhendriver 3]

I dont't have any power lever hardware, so think its not the case.But fortunately I'm not experiencing this problem anymore. I've edited the SID, cause it was a little outdated and the problem was apparently resolved. :( I had no more such occurrence.Anyway, thank you. :(

Since I too have been having issues with published procedures on climbout--Here's a technique only that gives me consistent climbout A/S and Attitude control:At the Gate: After EXT/APU PWR on1) Set 210kts as V2 in MCDU (TO/APPRCH page)2) Dial in 220kts in your MCDU FMS Speed bug (vice 250kts)3) Input 250kts in your CLMB page on MCDU (the edit function and select)4) Trim stab to green (around 4.5 will work)Before T/O Checks same (select NAV and AUTOFLIGHT)T/O ROLL same--V1 and VR are calledRotate to 15 Degrees indicated pitch--the pitch bars will be commanding more--so trim a bit nose down to maintain 15 degreesSpeed will accelerate to V2 + 10 (220kts)At 400-500' AGL select AUTOFLIGHT and PROFFlaps retract/Slats retractThe aircraft will accelerate to 250KIASIt will be smooth as butter vice following the commanded pitch bars which put the aircraft at 25 degrees indicated attitude and a slower V2+10--and if you're heavy as soon as you select AUTOFLIGHT and or PROF you may (almost always) hit the alpha limit which then commands a rapid pitch down to build speed. Again...JUST A TECHNIQUE...one that's working like a charm.Col (ret) Rich Perry

[MauB 74]

Since I too have been having issues with published procedures on climbout--Here's a technique only that gives me consistent climbout A/S and Attitude control:At the Gate: After EXT/APU PWR on1) Set 210kts as V2 in MCDU (TO/APPRCH page)2) Dial in 220kts in your MCDU FMS Speed bug (vice 250kts)3) Input 250kts in your CLMB page on MCDU (the edit function and select)4) Trim stab to green (around 4.5 will work)Before T/O Checks same (select NAV and AUTOFLIGHT)T/O ROLL same--V1 and VR are calledRotate to 15 Degrees indicated pitch--the pitch bars will be commanding more--so trim a bit nose down to maintain 15 degreesSpeed will accelerate to V2 + 10 (220kts)At 400-500' AGL select AUTOFLIGHT and PROFFlaps retract/Slats retractThe aircraft will accelerate to 250KIASIt will be smooth as butter vice following the commanded pitch bars which put the aircraft at 25 degrees indicated attitude and a slower V2+10--and if you're heavy as soon as you select AUTOFLIGHT and or PROF you may (almost always) hit the alpha limit which then commands a rapid pitch down to build speed. Again...JUST A TECHNIQUE...one that's working like a charm.Col (ret) Rich Perry

I'll try this. Thank you! :(