Random Overspeed and Autopilot Disconnect in Climb/Cruise

[Arz2934 2]

Hi everyone 

I just bought the 777, but there is one issue I have had on most of my flights. This did not happen when I flew the tutorial flight, but every flight thereafter.

 

During the climb (above 10000 feet) and cruise portion of my flight, my 777 will randomly over speed. As an example, I was flying from VECC-OMDB, and I was climbing through 14 000 feet. I was flying at 308 knots, and the red lines on the airspeed indicator were at about 325 knots. Everything was going well until suddenly, the speed popped up to 400 knots, triggering the over speed alarm, and disconnecting the autopilot. Then, just as the situation occurred, it corrected itself. This usually happens multiple times throughout my flight, and usually, during the cruise, the situation doesn't correct myself as it does during climb. 

I always derate my takeoffs with an assumed temperature, or a fixed derate, if not, both. I don't understand why I am having this issue, I fly my routes just like I flew the tutorial flight, but the issue still persists. 

I have conducted a forum search, but I got no results, however, I may have overlooked something, if there is a previous topic on this issue, I apologize, and would appreciate if I could get a link to that topic. 

Any help would be greatly appreciated. 

[Jeff H 63]

I'm curious, what do you use for your weather, FSX weather settings or a third party program?  From what you describe, it sounds like you're getting some sudden wind shifts.  An easy test would be to clear all your weather and then make a flight to see if the problem persists.

Regards,

Jeff

[flyerboy 114]

Sounds like your using an external weather engine.

[Arz2934 2]

I'm curious, what do you use for your weather, FSX weather settings or a third party program?  From what you describe, it sounds like you're getting some sudden wind shifts.  An easy test would be to clear all your weather and then make a flight to see if the problem persists.

 

Regards,

Jeff

 

I am using Opus for my weather, to match up with PFPX. This does seem like a possible scenario, given the tutorial flight was done with clear weather. However, I have flown many hours with the NGX using my weather engine, problem free. I will try to fly a clear weather flight and see what happens though. 

 

Thank you for your suggestion. 

[hopskip 253]

I have always used FSUICP to smooth winds. It won't kill gusts (Which are programmed to the simulator as "Gust" not "Windspeed") - it will however stop the wind getting an erronious update and suddenly spinning that 50 knot tailwind into a 50 knot headwind in a tenth of a second or less. ( equal to a 100 knot increase in winds in a single frame).

[777simmer 117]

I am using Opus for my weather, to match up with PFPX. This does seem like a possible scenario, given the tutorial flight was done with clear weather. However, I have flown many hours with the NGX using my weather engine, problem free. I will try to fly a clear weather flight and see what happens though. 

Thank you for your suggestion.

 

Sudden wind shifts causing overspeed have allways been a problem in FSX.

 

OPUS is trying to do all it can to get that under control.

But you need to update their software (updates are presented very very often as the program is continuously being improved and more functions are being added).

 

And you need to read the manual about how to use the settings to stablize winds and thus airspeed.

 

 

If that does not help then post a question at their forum and you will usually get an answere on the same day!