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Wennerholm

To Low Speed

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Hi! When I perform a take takeoff, I nearly reach Vr. speed. Then when I get into the air, the speed decreases to Stall speed. And yes, I hit the ground a little bit to hard. Take a look at the attached photos from this particular flight.

 

 

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KqYnNUgcuL85-2i9lBSI0PgTfMlp7VhbptT47nts

tTZsvEImqIbYsN-zGYPGpvGzYQ5zObQrRfr0H9cP

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Most likely your throttle controller is cancelling TOGA and you are not setting thrust at THR REF.  Your FMA indicates HOLD but above V1 it should go to THR REF.  Calibrate your throttles.  The FMA is the first place you look when you ask the question why is it doing that... and the FCOM has extensive documentation of how to interpret what you see, or don't see.

Please be sure you have flown the Tutorial.


Dan Downs KCRP

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Yes, Thank´s! FMA shows THR REF when I accelerate up to V1. I push the TO/GA button in the same time THR REF shows up (at about 65 N1). Maybe I need to calibrate my throttle. 

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With hardware throttles, even when you hit TO/GA, you need to push your throttles forwards. When it goes into HOLD mode, it just holds the position of your throttles, and if your throttles aren't forwards, you'll actually lose thrust. That said, we need to see your upper EICAS screen to see what you were looking at. The information you've provided, whilst useful, is incomplete.


Captain Kevin

nGsKmfi.jpg

Air Kevin 124 heavy, wind calm, runway 4 left, cleared for take-off.

Live streams of my flights here.

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Just another thing I noticed, you’re taking off with an 8 knot tail wind component? Also, you don’t need to put in runway slopes into the FMC, FSX/P3D doesn’t have sloped runways. 

Finally, it’s 15 degrees outside and you’re using an assumed temp of 60 degrees. That’s very very high how are you calculating your assumed temp?

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6 hours ago, PMDG777 said:

Just another thing I noticed, you’re taking off with an 8 knot tail wind component? Also, you don’t need to put in runway slopes into the FMC, FSX/P3D doesn’t have sloped runways. 

Finally, it’s 15 degrees outside and you’re using an assumed temp of 60 degrees. That’s very very high how are you calculating your assumed temp?

Hi! The truth is, I do not know how to calculate the assumed temperature. Is there any free software that can calculate the value or just doing it manual?

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10 hours ago, Captain Kevin said:

With hardware throttles, even when you hit TO/GA, you need to push your throttles forwards. When it goes into HOLD mode, it just holds the position of your throttles, and if your throttles aren't forwards, you'll actually lose thrust. That said, we need to see your upper EICAS screen to see what you were looking at. The information you've provided, whilst useful, is incomplete.

I use to push my hardware throttle fully forward after pushing TO/GA.

10 hours ago, Captain Kevin said:

With hardware throttles, even when you hit TO/GA, you need to push your throttles forwards. When it goes into HOLD mode, it just holds the position of your throttles, and if your throttles aren't forwards, you'll actually lose thrust. That said, we need to see your upper EICAS screen to see what you were looking at. The information you've provided, whilst useful, is incomplete.

 

10 hours ago, Captain Kevin said:

With hardware throttles, even when you hit TO/GA, you need to push your throttles forwards. When it goes into HOLD mode, it just holds the position of your throttles, and if your throttles aren't forwards, you'll actually lose thrust. That said, we need to see your upper EICAS screen to see what you were looking at. The information you've provided, whilst useful, is incomplete.

 

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10 hours ago, Captain Kevin said:

With hardware throttles, even when you hit TO/GA, you need to push your throttles forwards. When it goes into HOLD mode, it just holds the position of your throttles, and if your throttles aren't forwards, you'll actually lose thrust. That said, we need to see your upper EICAS screen to see what you were looking at. The information you've provided, whilst useful, is incomplete.

   I use assumed temp 30 in today´s flight. T/O went without a problem. When I approached waypoint Belag between UUEE-ESSA with my A/P connect the aircraft start a descent and turn to the right. I take control and manually put my 747 at the right heading and ALT. Then I reconnect A/P and the aircraft start to follow the route again. I add 3 picture from the incident. I also see a message in the ECAM: IRS DC right, center, left

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27 minutes ago, Ken Wennerholm said:

   I use assumed temp 30 in today´s flight. T/O went without a problem. When I approached waypoint Belag between UUEE-ESSA with my A/P connect the aircraft start a descent and turn to the right. I take control and manually put my 747 at the right heading and ALT. Then I reconnect A/P and the aircraft start to follow the route again. I add 3 picture from the incident. I also see a message in the ECAM: IRS DC right, center, left

N5AjVByib-3yH3jQfXhqfZi8QlaISjB6g0k2hWANGXvos7BsddU3lr-trJy9mZl-8WLmLueCS20oPIkHziLIT4Y-lpro-lxpujLZkv9Vq4xjwsE_gns8sHzu

Something definitely isn't set up right. Your VNAV shouldn't have that yellow line through it and you should have a horizontal and vertical line for your flight director. Your FMC legs page looks fine.

I noticed on your PFD, you're way overspeed yet you have 329 set in the MCP speed window (which is fine), does it suddenly jump to that? This might be active sky being incorrectly set up. Try running without active sky.

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Just now, PMDG777 said:

Something definitely isn't set up right. Your VNAV shouldn't have that yellow line through it and you should have a horizontal and vertical line for your flight director. Your FMC legs page looks fine.

I noticed on your PFD, you're way overspeed yet you have 329 set in the MCP speed window (which is fine), does it suddenly jump to that? This might be active sky being incorrectly set up. Try running without active sky.

Hi! my 747 start a steep dive therefore the over speed. It dive from FL310 to FL270. Before the problem starts the VNAV has no yellow stripe. The horizontal and vertical line in flight director was also displayed as normal. The incidents appears quickly. I hade same problem before the AS16+ASCA.

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7 minutes ago, Ken Wennerholm said:

Hi! my 747 start a steep dive therefore the over speed. It dive from FL310 to FL270. Before the problem starts the VNAV has no yellow stripe. The horizontal and vertical line in flight director was also displayed as normal. The incidents appears quickly. I hade same problem before the AS16+ASCA.

Hmmm. Can you try with no external joystick, throttle, rudder etc. to rule out bad hardware. Just use keyboard and mouse.

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You should be flying the Tutorial.  I think you are wasting your time trying to ad lib unless you can do the tutorial without incident.


Dan Downs KCRP

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Just now, PMDG777 said:

Hmmm. Can you try with no external joystick, throttle, rudder etc. to rule out bad hardware. Just use keyboard and mouse.

Yes! I have try without hardware now. The same thing happen again.5OtIgtIbNBSlAre4qXbsnbiDRxpm76t9FPvUEGsRIVANxyJZDPRosc8MlrH9v001JrRLdiPkK_a3LMKA

 

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You can inhibit hardware throttle input when A/T is engaged through FMS->Menu->PMDG Options->Simulation

What you've just seen is your hardware throttle forcing a high power output causing an overspeed situation. It's like in a real 747 the pilot is overiding the autothrottle by using his/her hand to hold the throttle quadrant in a high power position.


Zicheng Cai

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19 minutes ago, Cai Zicheng said:

You can inhibit hardware throttle input when A/T is engaged through FMS->Menu->PMDG Options->Simulation

What you've just seen is your hardware throttle forcing a high power output causing an overspeed situation. It's like in a real 747 the pilot is overiding the autothrottle by using his/her hand to hold the throttle quadrant in a high power position.

Hi! I sm not sure. My speed drops to stall speed before I take control manually. When my 747 dive it cause over speed.

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