Test flights verify craft's performance

Test flights at sea are necessary in researching and developing a seaplane to verify the aircraft's performance and suitability for the task, said Liu Ying, deputy chief designer of the AG600 amphibious aircraft.

Liu, who is also head of an Aviation Industry Corp of China test flight base and in charge of the AG600's testing project, said the first flight at sea is especially important because it shows how compatible the aircraft is with ocean conditions, explores techniques and methods for future sea-based tests, and builds the foundation for subsequent testing of wave-resistance, maneuverability and the apparatus on board.

Asked about the differences between lake and sea tests, he said the first step in amphibious aircraft flight testing is the takeoff and landing performance on land, which examines the plane's basic capabilities and flight performance.

The second phase－lake or reservoir tests－checks whether the aircraft can land and take off on water and perform water-related operations such as pumping up water.

In the final phase, designers and engineers use sea tests to verify the plane's overall operational capability with real conditions and study whether it can endure tough situations at sea, he said.

Tests at sea are more difficult and challenging than those on lakes, he said, citing a host of external factors ranging from bigger waves, higher temperatures, humidity and salinity to higher odds for contingencies or malfunctions.