Following several earlier unsuccessful attempts to develop an airmail system using Leviathan, in 1929 a further attempt was made. A large trap was built on the deck: this consisted of a frame attached to the top of the aft deckhouse on the Poop Deck, extending over the side of the ship. This frame was 35 feet wide, and contained a canvas trap. An aircraft would ﬂy low overhead trailing a long cable to deliver and pick-up mail bags. The plan was for the pilot, Lt Cmdr George Pond, to rendezvous with Leviathan some 500 miles out from the US coast. Leviathan sailed from Southampton on 2nd June 1929 with 957 passengers, and was due to be at Grand Banks on 7th June, where the mail pick-up was to be attempted. On 5th June Pond crashed the plane at New York. A Loening seaplane was hastily ﬁtted with the Adams pick-up ﬁtting and he successfully took off. However, he encountered bad weather and lost his position, and soon after the aircraft was hit by lightning. He was forced to abandon the attempt.
The next morning Pond attempted again. This time he was successful in ﬁnding Leviathan; unfortunately no-one had informed Leviathan of the repeat attempt so the system hadn’t been set up, and heavy fog hampered the attempt. Eventually the two bags of specially-franked mail were landed on the liner with the regular mail. The company decided to try again on the next crossing. Leviathan sailed on 12th June 1929 with 2,132 passengers. As she passed Fire Island, some 60 miles out, a small Fairchild monoplane ﬂew overhead, piloted again by Pond from Keyport airport. This time he found Leviathan quite easily. On his ﬁrst attempt, Pond dropped a bag of mail into the pick-up frame. The collection wasn’t quite as easy, and he had to make 13 attempts before he was successful in picking up and reeling in the mail bag from the Adams frame. A number of photographers were ﬂying alongside to record the event.
On 16th July Leviathan headed for Boston for her routine mid-season drydocking. During the trip another attempt was made to deliver and collect mail using the Adams frame but it was a failure. On the return trip an aircraft ﬁnally managed to drop four bags of mail onto Leviathan using the Adams system. However it was agreed the system was not that effective and soon after US Lines abandoned the whole idea.