A lorry driver was trapped in the air after the ramp onto the Calais to Dover ferry rose while the vehicle was being driven onboard.
Cars were queuing to board the Irish Ferries vessel from Calais to Dover just after 8pm on Sunday when the ramp began to close.
A van sitting on the ramp was gradually at least three metres into the air - leaving the driver trapped.
Adrian Cann, 36, whose car was two vehicles back, said he was worried it would roll backwards.
Staff came to assist after about five minutes, he said, and the ferry sailed for Dover at 8:30pm - about 20 minutes late, he said.