This weird issue started popping up for me not too long ago.

It started with the JS41. On climbout I would barely hold a 300-400 fpm climb with max RPM and EGT lines at their max allowed temp. It wouldn't happen on all flights, but on some it would.

 

Now the same has started happening with the NGX. Yesterday I tried a flight out of KLAX. The takeoff roll, V1/VR/V2 went fine, but after I passed 1,000ft and nosed down at acceleration height, I noticed that my plane wasn't gaining speed but was actually losing speed.

What's also weird is that I had to nose down to almost -5 degrees of pitch before I started gaining airspeed, as if the flight characteristics were drastically altered.

 

Even weirder, I brought the nose to 0 degrees of pitch, and my rate of climb was 1,400 fpm. Flaps and gear were up (triple checked), aircraft was completely clean.

Checked the CDU...no failures active

 

I run Active Sky 2012 in DWC mode. Someone hinted at me in the JS41 forum that he heard others had experienced a bug with temperature changes and loss of thrust in the JS41....I just didn't think it would be related to the NGX too, if it is at all.

 

Anyone else experienced this or heard of this issue before? I think I'm just going to reinstall both the JS41 and the NGX and see what happens after that.

Besides dodgy weather, Do you use FSUIP?

 

Could also be that your joystick numbers changed in FSUIP, I had engines powering down at full throttle once in the EJets. It was my mixture assignment in FSUIP, the joystick number changed and it thought full throttle was inverted mixture, hence cutting engines.

 

Not sure if NGX is affected by mixture though but almost any plane will be in the background.

 

But for you it could be conflicting throttles.

 

What's your N1?

 

With FSX, it could be lots of things..

I only use one throttle assignment, and it's through FSUIPC along with the calibration for it.

I deleted all axis assignments through FSX itself (even the slew assignments) including all the mixture assignments.

 

I doubt it's mixture related, but I'm going to reassign all my Saitek levers anyway.

N1 was at 100% when I was losing speed while pitched down at acceleration height.

 

I reinstalled both aircraft tonight...going to test them out and see if the issue reproduces.

Out of curiosity, what was the OAT? Anything above around 95 degrees F really starts killing turbine performance. I was flying a turboprop today, departure OAT was 100 dgrees. I normally climb at 1700 FPM. In order to keep ITT below 700 degrees using engine torgue and RPM, I could only achieve 1100FPM or less until I got to about 12000 ft wwher OAT started dropping sharply.

I used real weather, so check the history of KLAX weather from last Saturday night, 7/21.

Whatever it was around 0200 GMT is what I was experiencing in FSX.

 

*edit*

from http://www.wunderground.com

 

Mean Temperature 21 °C

Max Temperature 23 °C

Min Temperature 17 °C

 

According to their temperature graph, around 7pm that day it was about 19-20* C.

SOLVED

 

I reset my controls through FSUIPC last night, disabling each one by one to see if there was any improvement during my test flight.

As soon as I deleted the flaps axis, my flight characteristics returned to normal. Now I understand why PMDG put a disclaimer in the NGX introduction pdf about NOT setting axis mappings through FSUIPC.

 

FSUIPC is cool in the way it will automatically determine how may flap settings the aircraft has and set the number of "detents" in the axis movement when you push a hardware lever up or down, but even at 0 with the flaps showing 0 in the cockpit, somehow the flaps were still lowered to some degree and that's why I had such a high angle of attack.

 

I remapped flaps to the FSX controls and all is well. Lesson learned!

This also explains why it was happening with the JS41 too, but not any other aircraft. Something with PMDG doesn't like FSUIPC axis mappings.

Awesome.

 

FSUIP has been good except when joystick # changes it throws some weird things at you.

SOLVED

 

I reset my controls through FSUIPC last night, disabling each one by one to see if there was any improvement during my test flight.

As soon as I deleted the flaps axis, my flight characteristics returned to normal. Now I understand why PMDG put a disclaimer in the NGX introduction pdf about NOT setting axis mappings through FSUIPC.

 

FSUIPC is cool in the way it will automatically determine how may flap settings the aircraft has and set the number of "detents" in the axis movement when you push a hardware lever up or down, but even at 0 with the flaps showing 0 in the cockpit, somehow the flaps were still lowered to some degree and that's why I had such a high angle of attack.

 

I remapped flaps to the FSX controls and all is well. Lesson learned!

This also explains why it was happening with the JS41 too, but not any other aircraft. Something with PMDG doesn't like FSUIPC axis mappings.

 

Thank you AJ - I think I understand how this particular issue happens now thanks to these findings. I knew deleting the FSUIPC4.ini and rebuilding it fixed the issue but I didn't know it had to do specifically with the flaps... It's internally using "flaps" even though the model doesn't show it because of how we had to code all the animations and stuff.