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maf

Sudden loss of directional control

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So, im no stranger to any of the majestic birds. Ive flown them for years.

 

Today, however, I ran into a problem that I just cannot figure out the why´s of, and

something ive never experienced.

 

I flew one leg, landed and got ready for another flight.

 

As I lined up for the runway, I was heavy, it was short. I had selected

flaps 10, bleeds off, (two settings I dont use that often, as I fly seldom fly into airports with short rwys)

 

MTOP was selected and I applied to-pwr while holding my brakes, let go as pwr was set

and started the roll.

 

As i approached 60-80 kts aircraft started veering off hard to the left. No input was helping.

I aborted take off, and made another 2 attempts. I even turned off nose wheel steering, but

it just kept veering off. As I made hard right rudder to counteract it, the take off alarm sounded

(which I assume is related to too large control inputs during takeoff roll)

 

The set up for nose wheel steering and rudder, has been like this on just about

all my flights.

 

So Im quite puzzled as to the reason why I had such problems keeping it centered on the rwy

(a problem ive never had before).

 

Any inputs and help is greatly appreciated!

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This is quite normal on the Dash 8, the props are counter rotating, both props turn the same way unlike the ATR's,  just set right rudder trim to counteract the tendancy to veer

to the left and you should be ok,

 

I tend to set the trim just short of the first mark on the guage and that works for me, only slight rudder input to the right needed to keep on the centreline

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Firstly, the alarm you hear is the takeoff configuration warning, so something is not set correctly for takeoff (elevator trim, flaps, anti-skid etc)

 

Secondly, it is normal for the Q400 to go left at high power settings and low speed, this is because the propellers both rotate in the same direction. You counteract this using right rudder, if you are struggling with this you have two options:

 

1) Trim the rudder right by about 15 units before takeoff

2) Disable the propwash effects in the mjc84.ini file, the entry needs to read YAW_DUE_TO_PROPWASH=0 (instead of default 1.0)

 

In either case you need to make sure your controls are properly calibrated within th MJC84 Control Panel.

 

If you have any further issues I have written a brief FAQ at http://viaintercity.com/forums/bombardier-dash-8-q400-%28dhc-8-402q%29/faq-%28frequently-asked-questions%29-and-tips-for-dhc-8-402q/

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This is quite normal on the Dash 8, the props are counter rotating, both props turn the same way unlike the ATR's, just set right rudder trim to counteract the tendancy to veer

to the left and you should be ok,

 

No, not this. I know what youre talking about, but this was something quite different. I veered off the runway regardless of rudder input etc. No engine malfunction,

all fine. Very puzzling. Ive had countless take-offs in this machine, and the effect you mention, I can handle. This, however, is just not possible to overcome.

 

Thanks for the input, however. I appreciate it!

 

 

 


Firstly, the alarm you hear is the takeoff configuration warning, so something is not set correctly for takeoff (elevator trim, flaps, anti-skid etc)

 

Yes, I know that very well. As mentioned, Ive flown the majestic machines for years, Im no stranger to how you set up the

dash 8 for takeoff. However, the take-off alarm comes on about 60-80 knots into the take-off roll, as I try

to counteract the veering with hard, right rudder.

 

 

 

 


2) Disable the propwash effects in the mjc84.ini file, the entry needs to read YAW_DUE_TO_PROPWASH=0 (instead of default 1.0)

 

This one I will try!

 

Alright you guys, thanks for the inputs! I appreciate that you do an effort and try to help B)

 

Im gonna try the ini-file input and experiment with nose-wheel steering. I think somethings gone wrong there..

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