1. While being flown by a champion amateur cyclist in 1963, the plane crashed on an airfield.
    在 1963 年，当一位业余自行车赛冠军驾驶这架飞机的时候，它坠毁在机场上。

2. When the plane arrived, some of the detectives were waiting inside the main building while others were waiting on the airfield.
    当飞机到达时，一些侦探等候在主楼内，另一些侦探则守候在停机坪上。

3. Soon afterwards, the balloon began to descend and it landed near an airfield.
    不久，气球开始降落，在一个停机坪附近着了陆。

4. Guards patrolled the perimeter of the airfield.
    卫兵沿机场四周巡逻.