JAL,
The series is The Weapons That Made Britain.
Hosted by a medievil weapons guru who apparently stages battles / stunts for the movie industry. Among other things, he tested the accuracy of the longbowmen at different distances, the pace at which the longbowmen could launch arrows versus the French hired mercenaries using cross-bows (2:1), and the time it would have taken for the French armored cavalry to cross the field of battle. Riding at full gallop they would have been pelted with 60,000 arrows from the 7500 longbowmen during their 40 seconds charge, according to the tests conducted.
Needless to say, the English opened up a can.
Mike