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Demious

Is this normal behaviour?

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I've been spending quite some time in the Q400 this week and I notice behavior I'm not used to from other aircraft and it seems a bit contradictory to me.

The aircraft is constantly flying with the right wing dipped low and the nose is 10-15 degrees turned left from the given course. I also regularly notice eradicate behavior, the nose swaying from left to right, which can go as far as over 10 degrees and also airspeed and altitude get very jumpy, way more than I'm used to from any other aircraft I've flown, in heavy winds.

In heavy winds I'd expect such behavior, but this happens in winds as low as 12-15kts, while on the other hand, I see the aircraft fly very smooth with wind speeds as high as 50kts.

It starts with no change in weather conditions, flying level in cruise and can stop as easily as it's started. Sometimes it's just a short while and it will stop within a minute, but I also had it continue for the better part of a flight of well over an hour.

 

Am I overlooking something from the aircraft's behavior that causes this, or could there be something going on here that needs fixing?

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Put in about 3 degrees of right rudder trim and try it. 

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A little rudder trim indeed keeps the aircraft wing level and pointing forward, but it didnt solve the violent swaying.

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@Demious

 

 

I've been spending quite some time in the Q400 this week and I notice behavior I'm not used to from other aircraft and it seems a bit contradictory to me.

The aircraft is constantly flying with the right wing dipped low and the nose is 10-15 degrees turned left from the given course. I also regularly notice eradicate behavior, the nose swaying from left to right, which can go as far as over 10 degrees and also airspeed and altitude get very jumpy, way more than I'm used to from any other aircraft I've flown, in heavy winds.

In heavy winds I'd expect such behavior, but this happens in winds as low as 12-15kts, while on the other hand, I see the aircraft fly very smooth with wind speeds as high as 50kts.

It starts with no change in weather conditions, flying level in cruise and can stop as easily as it's started. Sometimes it's just a short while and it will stop within a minute, but I also had it continue for the better part of a flight of well over an hour.

 

Am I overlooking something from the aircraft's behavior that causes this, or could there be something going on here that needs fixing?

The aircraft by design will not handle like most of your other FS aircraft, however the FDM has been thoroughly tested by Q400 professionals to ensure that we werre able to simulate the aircraft's handling characteristics.  the issue that you encountered with the aircraft flying wing down and the nose pointing away from the desired course is due to the fact that rudder trim needs to be applied after takeoff and to counteract the prop_wash.  There are several threads regarding this on the Majestic Software forum, please take a moment to search and review some of these topics as they will offer a wealth of additional information that will assist you in better understanding how to manipulate the controlsof the aircraft.

The other issue that you speak of appears to be indicative possibly of your weather generator turbulence settings i.e. ASN, OPS, etc.  or the turbulence setting of the Q400 which can be down-scaled in the mjc84.ini file.

One may also opt to disable the PROP_WASH feature but this takes away from flying the aircraft the way it is designed to be flown.

By the way, what version of the Majestic Q400 are you running?

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AIRCRAFT YAWS/ROLLS LEFT AFTER TAKEOFF
The left tendency is caused by yaw generated from the "prop wash", as both props on the Q400 turn in the same direction. Counteract it using the rudder pedals and trim; set rudder trim right about 14 units before takeoff and you'll have a lot less to fight with once your airborne. You'll need to gradually reduce the trim as you accelerate, neutralising it when you're in the cruise. Every time you change the power settings, you will need to retrim the rudder.

You can disable the propwash using the mjc84.ini file if it's annoying you, add the following line:
YAW_DUE_TO_PROPWASH=0 (instead of default 1.0)

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No need to disable anything if it is how this aircraft should behave. It's not that I cant handel it, it's just that this is behavior I dont know from other aircraft, so I was in doubt if it was something that needed to be fixed, or if it is typical behavior I need to take into account.

 

Thanks for the info, guys! :)

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