How to control climb rate after TO w/ VNAV enabled

[Noel 4,494]

Not sure what's up but the climb rate gets extreme and FSCaptain don't like it one bit!   I had initially used vertical speed set rather than VNAV and of course that works, but my sense from FSX days (using P3D now w/ T7) was that climb was exquisitely controlled w/ VNAV enabled.   Any ideas what I may be doing wrong?   I will spool up to 55% EPR, hit the TO/GA button and advance throttles, take off and control the climb rate w/ trim then when I hit the autopilot she shoots up to a climb rate of 5500+.

 

While I'm here, also when I have to do a manual/non-autoland, I can't figure out how to get the blooming horn to shut off after disengaging the autopilot to manually land.  I tried hitting the  Z key twice and it temporarily shuts off the horn but it will then come back on and stay on no matter what I do.

 

Thanks in advance!

[chiozza 0]

Sam issue here but I started pitching to 10 degrees stable before hitting AP. Also to stop the horn its control shift Z

[pcubine 143]

 

 

when I hit the autopilot she shoots up to a climb rate of 5500+.

If the pane has a light to medium load with fuel for a 4-6 hour flight, 5500+FPM is in the ballpark.

[scandinavian13 5,192]

Any ideas what I may be doing wrong?

 

Yes.

 

To be blunt, you're bending your flying to a product that isn't coded to be realistic. FSCaptain might add a feeling that things are more realistic because you have to follow procedures, but many add-ons that watch your vertical speed (to include FS2Crew) are hopelessly incorrect when it comes to penalizing or warning you for it.

 

People do not feel rate, they feel acceleration. The same way you feel natural going 450 knots through the air in a 777, you feel natural in a 5500 feet per minute climb/descent. The issue, however, is the rate at which you go from 0 to 5500. That's what people feel, as that's acceleration.

 

So, my advice would be to either disable that metric, or ignore it. The add-on is unrealistically flagging you for normal operation. It would be like flagging you for putting the flaps down.

 

All that said, if you'd like to tame the climb, use a takeoff and climb de-rate. In order to calculate more realistic climb de-rates, though, you'll need a program like TOPCAT.

 

 

 

While I'm here, also when I have to do a manual/non-autoland, I can't figure out how to get the blooming horn to shut off after disengaging the autopilot to manually land.  I tried hitting the  Z key twice and it temporarily shuts off the horn but it will then come back on and stay on no matter what I do.

 

This one is clearly explained in the into manual, but for your convenience, I made a video a while back because this one seems to stump people a lot:

 

What's happening is that you're hitting Z, which disables the autopilot, but starts the alarm. You're then hitting Z again, which re-enables the autopilot (Z is the default FSX AP ON/OFF toggle), but you're probably manipulating the controls at this point, which again, kicks the AP off and the alarm goes off.

 

As mentioned in the video, it would probably be best to set up a key command in the CDU menus for AP disconnect. This is a one-way switch: OFF. That way, hitting the button twice will: 1 - turn off the AP, and 2 - tell the automation that the action was intentional, and disable the alarm.

[alexzar14 5]

I have a button assigned to my CH Yoke, click that twice for disengage. One of the red buttons, very convenient.

By the way, double-click works with all aircraft but with the iFly 747, click the button then reset the bar on the AP panel, gotta ask them one day.

What I like PMDG for, it is one developer where everything works like a mechanism in the swiss watch -))))

 

PS, Kyle can you please remind me, on PMDG 747, does the double-click disengage and silence the autopilot or you still have to reset it by pressing on the bar?

[scandinavian13 5,192]

 

 

PS, Kyle can you please remind me, on PMDG 747, does the double-click disengage and silence the autopilot or you still have to reset it by pressing on the bar?

 

To be honest, I've forgotten. For a plane that was my first PMDG purchase (the original FS9 release anyway), with a ton of hours in it, I didn't even bother re-installing it a few years ago when I reformatted my machine.

 

I thought you could set up an AP disconnect key command in the Options menu (up on the FSX menu bar). I could be wrong.

[Noel 4,494]

Gr8, thank you all for these quality tips and suggestions.  I'll give it a whirl!

 

Noel

[skelsey 765]

 

 

Kyle can you please remind me, on PMDG 747, does the double-click disengage and silence the autopilot or you still have to reset it by pressing on the bar?

 

I'm nit Kyle, but I can confirm it does!

 

The A/T is a different matter, however -- there is no 'soft' disengage (at least not that I've found over the last three years) so the only way to disengage the A/T is to use the 'disarm switch on the MCP (twice to silence the alert/EICAS message -- so it ends up back in the 'armed' position and armed but disengaged).

[ddswh1pk0s 8]

 

 

The A/T is a different matter, however -- there is no 'soft' disengage (at least not that I've found over the last three years) so the only way to disengage the A/T is to use the 'disarm switch on the MCP (twice to silence the alert/EICAS message -- so it ends up back in the 'armed' position and armed but disengaged).

 

There is a "soft" autothrottle disengage.

 

If you press CTRL-SHIFT-R then that presses the black button on the side of the throttle levers. Press it again the alarm will silence allowing full manual autothrottle control with no master caution message.

 

To engage the autothrottle again just press the A/T button on the MCP and you're good to go.

[albertz 0]

Noel

Try using Flap 20 for takeoff.

Aslo, select CLB2 when you enter the T/O perf data.

If all else fails, disconnect the A/T and reduce the N1 by a few.

The use of V/S is acceptable though as it effectively does the same thing as the line above by using thrust for speed.

There is a section in the FCTM about low initial level off altitudes to prevent the bird overshooting when its light, and although not quite the same thing, the techniques would apply equally here as its basically referencing high vertical speeds after liftoff.

Cheers

Matthew Knight

[skelsey 765]

 

 

If you press CTRL-SHIFT-R then that presses the black button on the side of the throttle levers. Press it again the alarm will silence allowing full manual autothrottle control with no master caution message.
 
To engage the autothrottle again just press the A/T button on the MCP and you're good to go.

 

Is that for the 747? I will give it a go, thanks!

[ddswh1pk0s 8]

 

 

Is that for the 747? I will give it a go, thanks!

 

Sorry I thought you were referring to the 777 but the same concept should apply in the 747.  However I'm not sure if theres a button shortcut since I don't have the 747.

[skelsey 765]

 

 

Sorry I thought you were referring to the 777 but the same concept should apply in the 747.  However I'm not sure if theres a button shortcut since I don't have the 747.

 

No worries Antoni -- we got diverted off on a little four-holer tangent when I answered Alex's question about the AP disengage on the Jumbo  ^_^. I will give it a go in any case -- I've not been able to find a 'soft' disengage option in the PMDG menu, but it may be that it's hidden elsewhere.

[Noel 4,494]

Noel

Try using Flap 20 for takeoff.

Aslo, select CLB2 when you enter the T/O perf data.

If all else fails, disconnect the A/T and reduce the N1 by a few.

The use of V/S is acceptable though as it effectively does the same thing as the line above by using thrust for speed.

There is a section in the FCTM about low initial level off altitudes to prevent the bird overshooting when its light, and although not quite the same thing, the techniques would apply equally here as its basically referencing high vertical speeds after liftoff.

Cheers

Matthew Knight

Thanks, you'll note in my OP I have been using V/S and that works along w/ derating, but I didn't recall this behavior in FSX version, but perhaps I've forgotten.   I will check out the section on the FCTM for this too--thanks!   I think Kyle's idea to disable the penalty in FSC is probably a good idea too for me.   Such a great plane though every part of it!  And shockingly good performance, overall.

[albertz 0]

There you go. From Page 4.3 on my FCTM (which might be different as its not PMDGs) I don't think I've busted any copyrights by posting it but let me know and ill delete if necessary. Sorry about the formatting.

On a side note, low level offs play havoc with your noise abatement so be ready to intervene the speed if you capture at 1000'.

Also, don't be afraid of speeding up. Deleting the speed restriction below 10000' on the VNAV CLB page saves gas, is more comfortable and does not strictly contravene the laws of aviation even in FAA controlled areas. Just look at minimum manoeuvre plus fifteen at max TOW on the -W.

 

High Takeoff Thrust - Low Gross Weight

When accomplishing a low altitude level off following a takeoff using high takeoff thrust and at a low gross weight, the crew should consider the following factors:

• altitude capture can occur just after lift off due to the proximity of the level off altitude and the high climb rate of the airplane

• the AFDS control laws limit F/D and autopilot pitch commands for passenger comfort

• theremaynotbeenoughaltitudebelowtheintendedleveloffaltitudeto complete the normal capture profile and an overshoot may occur unless crew action is taken.

  To prevent an altitude and/or airspeed overshoot, the crew should consider doing one or more of the following:

• usereducedthrustfortakeoffatlowweightswheneverpossible

• reducefromtakeofftoclimbthrustearlierthannormal

• disengagetheAFDSandcompletetheleveloffmanuallyifthereisa possibility of an overshoot

• usemanualthrustcontrolasneededtomanagespeedandpreventflap overspeeds. 

Cheers

Matthew Knight