Hi Lonewolf,
Originally Posted by Lonewolf_50
the change in heading to the right over the course of the descent, which would thus vary the airspeed depending upon what winds were at a given level
It seems to me that HN39 computed the wind direction relative to heading on this reconstruction, see his explanation:
Originally Posted by HazelNuts
It is based on wind 45 kt @125 deg, ISA +11 deg C, DFDR data for v/s, altitude and HDG.
Change of wind with altitude could be another factor of incertitude, but the end result would provide a good approximation.