Department of Occupational Safety and Health, China Medical University, Taichung City 40604, Taiwan.
Int J Environ Res Public Health. 2021 Dec 21;19(1):7. doi: 10.3390/ijerph19010007.
The purpose of this study was to investigate the effects of backrest angle and hand maneuver direction on maximum hand strength and to recommend a strength value for the hand-controlled stick of an aircraft.
Forty-eight female subjects were recruited to perform simulated forward-backward and adduction-abduction maneuvers using control sticks. Each subject was free from musculoskeletal disorders and pain. The independent variables included four control maneuvers (forward, backward, adduction, abduction), two right-hand control stick locations (central, side), and three backrest angles (90°, 103°, 108°). The dependent variable was maximum hand strength.
The maximum strength for forward maneuvers with both central and side sticks was strongest at a 90° backrest angle ( < 0.001). The maximum strength for adduction maneuvers with both central and side sticks was also strongest at a 90° backrest angle ( 0.001). On the other hand, the highest strength was observed at a 108° backrest angle when pulling the stick backward ( 0.001). The abduction strength was significantly stronger than the adduction strength with a central stick ( 0.001), but the adduction strength was significantly stronger than the abduction strength with a side stick ( 0.001- = 0.017). The forward and abduction strength were significantly different in different locations ( 0.001). The recommended strength in the Code of Federal Regulations (CFR) by the US FAA is higher than the strength values observed in this study.
The backrest angle, directions, and location affected the muscular strength. The recommended values should be reevaluated and adjusted for Taiwanese pilots.
本研究旨在探讨椅背角度和手操作方向对最大手部力量的影响，并为飞机手控杆推荐一个强度值。
招募 48 名女性受试者，使用控制杆进行模拟前后和内收外展运动。每位受试者均无肌肉骨骼疾病和疼痛。自变量包括四个控制动作（前、后、内收、外展）、两个右手控制杆位置（中央、侧方）和三个椅背角度（90°、103°、108°）。因变量是最大手部力量。
中央和侧方控制杆进行前向运动时，最大力量在 90°椅背角度时最强（<0.001）。中央和侧方控制杆进行内收运动时，最大力量也在 90°椅背角度时最强（0.001）。另一方面，向后拉控制杆时，108°椅背角度的力量最高（<0.001）。与中央控制杆相比，外展力量明显大于内收力量（<0.001），但与侧方控制杆相比，内收力量明显大于外展力量（<0.001-=0.017）。中央控制杆的前后和内收力量在不同位置有显著差异（<0.001）。美国联邦航空局（FAA）的《联邦法规法典》（CFR）推荐的强度值高于本研究中观察到的强度值。
椅背角度、方向和位置会影响肌肉力量。推荐值应重新评估并调整，以适用于台湾飞行员。
