Major
Court Treatt had had
experience of Crossley vehicles during World War I when they
were issued both as staff cars and tenders (light trucks) to all
squadrons of the Royal Flying Corps. He also used
one during his survey work for the air route and was pleased by how
they coped with rough ground.
For the expedition they used two
modified 25/30 chassis. These were a development of the Royal Flying
Corps tender and were sold by Crossley with a variety of car bodies or
with some adaption as commerical vehicles. Fitted with a
four cylinder 4,536 cc petrol engine they were rated as having a 30 cwt
payload. The expedition vehicles were modified in having
raised suspension, mosquito screens and a special body with a roof that
could be detached and
converted into a raft. This latter device was never actually used as
they were
abandoned not long into the journey to save weight.