PEEN, To cause a more corrosion resistant surface by   喷九，

multiple impacting it with a hard material such as steel 为形成防腐能力更强的表面，多次用诸如钢丸的坚硬材

pellets. Term for this is Shot Peening.                料冲击表面。这个过程名为喷丸硬化处理。

PERCENT MEAN AERODYNAMIC CHORD (% MAC),                平均气动弦百分比，

Defines a position on the aircraft relative to the mean  用来确定飞机上一点相对于机翼平均气动弦的位置。

aerodynamic chord of the wing.

PERCENT N 1 , Expresses the speed of the low           N1百分数，

pressure compressor rotor as a percentage of a fixed     以一定量的百分比而不以每一单位时间转数来表示低

amount rather than revolutions per unit time.          压压气机转子的转速。

PERCENT N2 , Expresses the speed of the high           N2百分数，

pressure compressor rotor as a percentage of a fixed     以一定量的百分比来表示高压压气机转子的转速。

amount.

PERFORMANCE DATA COMPUTER SYSTEM (PDC,                 性能数据计算机系统（PDC，PDCS），

PDCS), A device which provides data to achieve the       一个能提供数据，使飞机达到最有效和最经济的操作的

most efficient and economical operation of the airplane. 装置。

PHASE OF FLIGHT, A portion of flight specifically      飞行阶段，

devoted to accomplishing such things as takeoff, climb,  飞行中负有一定任务（如起飞、爬升、巡航、下降或

cruise, descent or landing.                            着陆）的部份。

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英汉对照民用航空词典                                      BOEING

PHILLIPS HEAD SCREW, A cross point screw with two      十字螺丝钉，

distinct tapers. Driven with a flat tipped Phillips head 螺丝的顶面有两个明显的锥形十字四槽的螺丝钉。由平

screwdriver (see Reed and Prince).                     顶十字头螺丝钻驱动。

PITCH, The rotation of an airplane around its lateral  俯仰，

axis.                                                    飞机绕横轴运动而造成机头的上下运动。