Smith Adrian
BAE Systems, Dhahran, Saudi Arabia.
Aviat Space Environ Med. 2005 Aug;76(8):794-8.
During routine aviation medicine training, rotary-wing aircrew are instructed that the impact of hypoxia on them from flying in unpressurized cabins up to 10,000 ft (3048 m) above mean sea level (AMSL) is relatively small and has few implications for aviation safety. Such reassurance is based on data derived from experiments conducted on resting subjects and may not reflect the true impact of hypoxia in aircrew engaged in operational tasks.
A survey listing common symptoms of hypoxia was distributed to Australian Army helicopter aircrew who had operated at altitudes up to 10,000 ft AMSL.
There were 53 surveys that were returned (71% response), representing 25 loadmasters, 23 pilots, and 5 aircrewman technicians. All respondents were Australian Army aircrew. One or more symptoms consistent with hypoxia were reported by 86.6% of non-pilot aircrew and 60.9% of pilots. 60% of non-pilot aircrew reported four or more symptoms, compared with only 17% of pilots. The most commonly reported symptoms were difficulty with calculations (45%), feeling light-headed (38%), delayed reaction time (38%), and mental confusion (36%). Loadmasters reported more symptoms (mean 5.4) than pilots (mean 2.2) (p < 0.001). From the narratives provided (n = 21), aircrew experienced potentially operationally significant symptoms at a mean altitude of 8462 ft (2579 m).
The helicopter aircrew surveyed reported symptoms consistent with hypoxia at altitudes within the so-called physiological zone; loadmasters reported more effects than pilots. It may be inappropriate to emphasize the benign nature of the physiological zone during aviation medicine training of a non-resting population such as helicopter aircrew.
在常规航空医学训练中，旋翼机机组人员被告知，在平均海平面（AMSL）以上高达10,000英尺（3048米）的非增压机舱飞行时，缺氧对他们的影响相对较小，对航空安全影响不大。这种保证是基于对静息受试者进行的实验数据，可能无法反映从事作战任务的机组人员缺氧的真实影响。
向在AMSL高达10,000英尺的高度执行任务的澳大利亚陆军直升机机组人员发放了一份列出缺氧常见症状的调查问卷。
共收回53份调查问卷（回复率71%），其中包括25名载荷专家、23名飞行员和5名空勤机械师。所有受访者均为澳大利亚陆军机组人员。86.6%的非飞行员机组人员和60.9%的飞行员报告了一种或多种与缺氧相符的症状。60%的非飞行员机组人员报告了四种或更多症状，而飞行员中这一比例仅为17%。最常报告的症状是计算困难（45%）、头晕（38%）、反应时间延迟（38%）和精神混乱（36%）。载荷专家报告的症状（平均5.4个）比飞行员（平均2.2个）更多（p<0.001）。根据提供的叙述（n=21），机组人员在平均海拔8462英尺（2579米）时出现了可能对作战有重大影响的症状。
接受调查的直升机机组人员在所谓的生理区域内的高度报告了与缺氧相符的症状；载荷专家报告的影响比飞行员更多。在对直升机机组人员等非静息人群进行航空医学训练时，强调生理区域的良性性质可能不合适。
