Apollo 15 splashed down about north of Honolulu at 4:46 pm EDT () on August 7, 1971; the crew was retrieved by helicopters from the "Okinawa". Scott had asked that a supply of the twin space stamps of the design he had canceled on the Moon (issued August 2) be available on the "Okinawa", and on July 14, Forrest J. Rhodes, who ran the postal facility at KSC, wrote to the Chief Petty Officer in charge of the "Okinawa"s post office. The ship replied on the 20th, saying the stamps could be obtained in time. The stamps were secured from the post office at Pearl Harbor; 4,000 were flown to the "Okinawa" at sea by helicopter, reportedly in the custody of a naval officer joining the vessel. The astronauts had no money with them; their purchases were paid for by high-ranking officers aboard the "Okinawa", who were later reimbursed. The crew had the assistance of "Okinawa" crew members in affixing the stamps to the 400 covers for cancellation by the ship's post office. The Irwin covers were not postmarked, either at liftoff or splashdown. Worden wrote in his book that he never saw the covers Scott had brought until the astronauts were on the flight to Houston. However, as Scott mentioned he was having them postmarked with the splashdown date, Worden arranged to have that done for the ones he had taken into space. On the flight, the 400 covers were autographed by the three astronauts; the Herrick covers were also signed while en route. Irwin remembered the signing took several hours.