The U.S.military demanded three HAECO representatives in the trial flight, each from the Avionics Department, Airframe Department and Engine Department. Altogether there were five people on the plane, and they asked the ground to put in five parachutes at the rear. If anything happened, they said, you did up and jump out of the plane when I say jump!  Every trial flight had to reach the limit load, and we did it by piling up sandbags on the plane. It was not funny at all. They tested with different situations, like turning off the engine in mid-air to let the plane dropped for some three hundred or four hundred feet. My heart was like completely stopped!  It was regulated that the plane should fly out to Cheung Chau and Waglan Island; it kept going around at a specified altitude. You had to attend the trial flight when you were in charge of the maintenance. They would give you an airsick bag, though.

I attended a 707 trial flight once. We flew up to 8000 to 10000 feet, and then we cut the engine and the plane dived down. If we flew any further up we would get earache. Then we landed to test the wheel, and I was so happy when we touched ground. But it took off immediately afterwards. I felt so bad I didn’t want another trial. I didn’t throw up, but my ear ached so badly and I felt so sick. The engineer had to attend the flight, but we were just tagging along. One time was more than enough for me.