after each stopover, the pilots rested whilst the engineers checked the airplanes. then, at the beginning of the next flight, the engineers tried to sleep on the rear wing. during the flight between tripoli and cairo, one of the biplanes flown by rafael martínez estévez had to return to tunisia due to an engine failure. loriga, after flying through iran, pakistan, india and vietnam, was forced to execute an emergency landing for a leakage of water in the biplane. he landed in tien-pack harbour, close to guangzhou, in china; the crew were missing for several days, believed to have crashed into the ocean.