Question about CFD Simulation

User Support Hub Aircraft & Systems
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Hello,

i have enabled the CFD Simulation in my B737-800NG.
It works perfect for flying but there is only one Problem.

cfd_enablesimulation = 1
cfd_reinjectbody = 1
cfd_reinjectvtailx = 1
cfd_reinjecthtaily = 1
cfd_airviscosity = 0.05
cfd_airincompressibility = 1
cfd_voxelsizescale = 1.0
cfd_voxelnbvoxels = 20.0
cfd_groundcollisionvoxeloffset = 0.0

When you land a 737, you reduce the Thrust at 30ft and more or less just hold the attitude of around 2.5 - 3.0 degrees pitch.
Thats what i see in some videos of real airplanes and also on sim lessons on Youtube.

But in my case, when i reduce the Thrust ( gently ) at 30ft, the Aircraft immidiately looses all the Lift ( even if the Airspeed does not drop very fast ) and the Nose comes down. Then i have to pitch about 5 degrees to perform a more or less smooth Touchdown.

Is there anything i can do ?

Matthias

2

Moved to User Support Hub Aircraft & Systems that is more appropriate for community support.

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3

As per the 737-800 FCM:

Initiate the flare when the main gear is approximately 20 feet above the runway by increasing pitch attitude approximately 2° - 3°. This slows the rate of descent. After the flare is initiated, smoothly retard the thrust levers to idle, and make small pitch attitude adjustments to maintain the desired descent rate to the runway. A smooth thrust reduction to idle also assists in controlling the natural nose-down pitch change associated with thrust reduction. Hold sufficient back pressure on the control column to keep the pitch attitude constant. A touchdown attitude as depicted in the figure below is normal with an airspeed of approximately VREF. Ideally, main gear touchdown should occur simultaneously with thrust levers reaching idle.

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Thanks…i will try that.

Matthias

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