Sequence of events The aircraft entered the circuit on a left downwind leg for runway 18 from the south. The pilot was aware of another aircraft approaching from the north. The pilot said that the downwind checks were delayed because the speed of the aircraft was too high to lower the landing gear. He became somewhat distracted looking for the other aircraft entering the circuit. The pilot felt sure that he had lowered the landing gear. He said that neither he nor his passenger heard the landing gear warning horn before the propellers struck the bitumen runway surface. A post-flight inspection of the landing gear did not find any fault in its operation. Analysis The pilot probably forgot to lower the landing gear when he became distracted.