The advance party for Operation Bulbasket, including Tonkin, were flown to France by a Handley Page Halifax belonging to 'B' Flight, No. 161 Squadron RAF, the special duties squadron. Their drop zone was an area of the Brenne marsh south west of Châteauroux, which they reached at 01:37 hours on 6 June 1944, a few hours before the beginning of the D-Day invasion by the Allied forces of Normandy. With the advance team on the flight was Captain William Crawshay and the "Hugh" Jedburgh team. Crawshay was not pleased with the task of supporting Bulbasket "mistrusting the SAS men's ability to operate effectively and not compromise security.". Crawshay would later call the SAS "Sad Athletic Sacks."
