As they prepared to land, they first selected FLAPS 1 and noticed no change in their already poor roll control. When they went to FLAPS 2 the commander found that once again he required full left stick to keep the wings level. Having judged landing to be unsafe in these conditions, they reverted to FLAPS 1 and performed a go-around. The co-pilot looked at the Quick Reference Handbook and at the Flight Crew Operating Manual and obtained the correction data for a FLAPS 1 landing. They then landed in FLAPS 1 configuration in "direct law" and came to a stop without difficulty. The aircraft was towed to the stand, where the passengers disembarked normally.