I am a bit uncertain abou the proper use of the control surface delta block for the DATCOM forces and moments block in Simulink.

I noticed that when using import DATCOM with both the GRNDHT namelist for ground effect and the DELTA namelist for control surface deflections, the static stability derivatives are missing the values at various deflections at free-air ground height. To address this, I copied and filled in all the deflection values (6th index) coping the first value in the 6th index to fill in the free-air paraemters across all deflections. My assumption was that the DATCOM forces and moments block would use these to compute the forces and moments with no deflection, then add the control surface contributions seperately using dcm_sym, dcl_sym etc. However I only see a response to control surface delta inputs when the ground height signal is within the ground effect range, indicating that perhaps the DATCOM forces and moments block is not adding the dcm_sym, dcl_sym […] contributions and only finding coefficients from the cl, cl […] tables.

My question is, does the DATCOM forces and moments block read the incremental lift coefficients dcm_sym, dcl_sym […], or does it only apply the cl, cm […] coefficients for the current flight conditions, and are you supposed to manually apply aerdynamic coefficients using the aerodynamic forces and moments to account for forces and moments induced by the control surfaces?

Lastly, the units for the delta signal in Simulink state rad/s, I presume this is just a typo?

If anyone has any experience adding control surface contributions to a DATCOM simulink model, I would greatly appredicate your assistance!I am a bit uncertain abou the proper use of the control surface delta block for the DATCOM forces and moments block in Simulink.

I noticed that when using import DATCOM with both the GRNDHT namelist for ground effect and the DELTA namelist for control surface deflections, the static stability derivatives are missing the values at various deflections at free-air ground height. To address this, I copied and filled in all the deflection values (6th index) coping the first value in the 6th index to fill in the free-air paraemters across all deflections. My assumption was that the DATCOM forces and moments block would use these to compute the forces and moments with no deflection, then add the control surface contributions seperately using dcm_sym, dcl_sym etc. However I only see a response to control surface delta inputs when the ground height signal is within the ground effect range, indicating that perhaps the DATCOM forces and moments block is not adding the dcm_sym, dcl_sym […] contributions and only finding coefficients from the cl, cl […] tables.

My question is, does the DATCOM forces and moments block read the incremental lift coefficients dcm_sym, dcl_sym […], or does it only apply the cl, cm […] coefficients for the current flight conditions, and are you supposed to manually apply aerdynamic coefficients using the aerodynamic forces and moments to account for forces and moments induced by the control surfaces?

Lastly, the units for the delta signal in Simulink state rad/s, I presume this is just a typo?

If anyone has any experience adding control surface contributions to a DATCOM simulink model, I would greatly appredicate your assistance! I am a bit uncertain abou the proper use of the control surface delta block for the DATCOM forces and moments block in Simulink.

I noticed that when using import DATCOM with both the GRNDHT namelist for ground effect and the DELTA namelist for control surface deflections, the static stability derivatives are missing the values at various deflections at free-air ground height. To address this, I copied and filled in all the deflection values (6th index) coping the first value in the 6th index to fill in the free-air paraemters across all deflections. My assumption was that the DATCOM forces and moments block would use these to compute the forces and moments with no deflection, then add the control surface contributions seperately using dcm_sym, dcl_sym etc. However I only see a response to control surface delta inputs when the ground height signal is within the ground effect range, indicating that perhaps the DATCOM forces and moments block is not adding the dcm_sym, dcl_sym […] contributions and only finding coefficients from the cl, cl […] tables.

My question is, does the DATCOM forces and moments block read the incremental lift coefficients dcm_sym, dcl_sym […], or does it only apply the cl, cm […] coefficients for the current flight conditions, and are you supposed to manually apply aerdynamic coefficients using the aerodynamic forces and moments to account for forces and moments induced by the control surfaces?

Lastly, the units for the delta signal in Simulink state rad/s, I presume this is just a typo?

If anyone has any experience adding control surface contributions to a DATCOM simulink model, I would greatly appredicate your assistance! aerospace blocket, simulink, datcom, datcomimport, datcom forces and moments MATLAB Answers — New Questions

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