Q: Why does the ST_EXFORCE command report drift forces which do not look correct?
REV 5.08

A: What you are getting with ST_EXFORCE is not wave drift, but first order wave excitation. You can look at wave drift raos in the Hydrodynamics Menu with V_MDRIFT. To see the results in an irregular sea, do:

       &ENV -SEA .....

       &STATUS FORCE

The "wave force" printed here will be the mean wave drift corresponding to the sea you just defined.