Formation of images of spatial position during the development of illusions of vestibular origin

This paper discusses specific features of pilot's spatial orientation in response to spatial illusions of vestibular origin associated with their recognition and management. Analysis of data in the literature and observations by the present authors allow the conclusion that pilot's spatial orientation, once spatial illusions have emerged, makes him assess not only the instrumental information but also the pattern of his own controlling movements. As a consequence, it is suggested that in relation to the formation of a correct image of spatial position (particularly in the case of spatial illusions) pilot's controlling movements act as part of instrumental information concerning the spatial position of the flying vehicle.     

Fear of flying in civil aviation personnel.

Included in a multi-faceted questionnaire concerning the work environment within a commercial airline were questions on flight anxiety and exposure for critical incidents. A total of 1,147 respondents were included in the sample. Results show that 9.2% of the aircrew members feel anxious or afraid of flying monthly or more often. The cockpit crewmembers were less anxious than the cabin crewmembers, and female cabin crewmembers were more anxious than male. Aircrew who had experienced critical situations and had not sufficiently worked through their experiences, reported more anxiety than those with adequate work-through. We recommend that the cabin crewmembers be provided with better information on how the flight deck operates, and that more stable work crews and co-training of cabin and cockpit crewmembers be facilitated. A formal debriefing routine after critical incidents is advised. Personnel with flight anxiety should be offered help to reduce their fear level.     

Simulator-induced spatial disorientation: effects of age, sleep deprivation, and type of conflict

INTRODUCTION: Spatial disorientation mishaps are greater at night and with greater time on task, and sleep deprivation is known to decrease cognitive and overall flight performance. However, the ability to perceive and to be influenced by physiologically appropriate simulated SD conflicts has not previously been studied in an automated simulator flight profile. METHODS: A set of 10 flight profiles were flown by 10 U.S. Air Force (USAF) pilots over a period of 28 h in a specially designed flight simulator for spatial disorientation research and training. Of the 10 flights, 4 had a total of 7 spatial disorientation (SD) conflicts inserted into each of them, 5 simulating motion illusions and 2 involving visual illusions. The percentage of conflict reports was measured along with the effects of four conflicts on flight performance. RESULTS: The results showed that, with one exception, all motion conflicts were reported over 60% of the time, whereas the two visual illusions were reported on average only 25% of the time, although they both significantly affected flight performance. Pilots older than 35 yr of age were more likely to report conflicts than were those under 30 yr of age (63% vs. 38%), whereas fatigue had little effect overall on either recognized or unrecognized SD. DISCUSSION: The overall effects of these conflicts on perception and performance were generally not altered by sleep deprivation, despite clear indications of fatigue in our pilots.     

Crew workload in JASDF C-1 transport flight: II. Change in urinary catecholamine excretion

Serial changes in urinary catecholamine excretion were determined for 17 cockpit crews (6 captains, 6 copilots and 5 flight engineers) of JASDF C-1 aircraft during 10-hour (h) scheduled flights, in which captains and copilots performed almost the same flight tasks. The norepinephrine/epinephrine ratio (N/E) in copilots decreased significantly during the flight, whereas little decrease of the N/E was found in captains. Flight engineers showed an intermediate N/E value between captains and copilots. Hormonal responses appeared to correlate with differences in the amount of flying experience of crewmembers. Differences between captains and copilots were more significant when handling the aircraft. Results suggested that flight stresses perceived by crewmembers in the same cockpit were influenced by their flying experience and flight position which could be clearly assessed by determining relative excretions of epinephrine and norepinephrine.     

空军飞行员飞行错觉后反应分析

目的 掌握现阶段空军飞行员发生飞行错觉后反应状况,以期制定相应对策. 方法 运用"飞行错觉水平量表"对来院疗养的1275名空军飞行员进行飞行错觉问卷调查. 结果 有效量表1221份,飞行错觉总发生率为91.5%,发生错觉后看仪表不能克服的占8.1%,发生错觉后影响操纵的占32.7%,发生了错觉不知道的占6.9%,发生错觉后不能识别周围环境的占1.4%,出现不适症状的占56.6%.歼击机、强击机飞行员飞行错觉后的反应水平明显高于其他机种(P＜0.05).结论 空军飞行员飞行错觉后反应影响飞行安全,急待建立飞行错觉系统训练体系,减少飞行错觉后反应发生,降低飞行错觉反应水平. Abstract： Objective To investigate the Air Force pilots' response to the flight illusion for finding countermeasures. Methods A questionnaire entitled" the level scale of flight illusion" was inquired from 1275 pilots. Results The incidence of flight illusion was 91. 5% by analyzing 1221applicable replies. Among which even 8. 1% pilots could not overcome the illusions by observing instruments. 32.7% pilots reported illusion caused difficulties on aircraft control while 6.9% and 1.4% pilots respectively showed unawareness of illusion and lost the awareness of environment when illusion happened. 56. 6% pilots appeared discomfort. Fighter and attacker pilots showed stronger response than the other type of aircrafts' (P＜0.05). Conclusions Pilot's negative responses to flight illusions have effectively influenced flight safety. It is suggested to build up corresponding training system to control the pilot's negative response to flight illusions.     

Low back pain in the AH-1 Cobra helicopter

Pilots of the AH-1S helicopter maintain a vertical sitting position in the gunner's position (front seat), whereas in the pilot's seat (rear), they lean forward and to the left in order to operate the controls. A cross over study with pilots flying alternately in the front and rear positions was used to assess the effect of crew position on the prevalence of low back pain during flight. In the pilot's seat, there was an increased prevalence of pain (72.2%, 13/18 versus 55.6%, 10/18); the onset of pain was quicker than experienced in the gunner's position (64.3%, 9/14 versus 7.1%, 1/14, p less than 0.001); and the intensity was greater (85.7%, 12/14 versus 7.1%, 1/14, p less than 0.001). We conclude that posture is an important component of the low back pain experienced by helicopter pilots during flight.     

Phobic fear of flying in aircrews: epidemiological aspects and comorbidity

BACKGROUND: Phobic fear of flying may affect aircrew members during any phase of their flying careers. Symptoms are beyond voluntary control and may lead patients to avoid flying and seek medical advice. METHODS: Of 1101 psychiatric files from our institute for 1985-2002, 150 represented cases of fliers who suffered from phobic fear of flying. Data collected from those files included assessment of fear-evoking situations, type of aircraft, class of aircrew duties, aircraft accident history, past medical history, age, and associated psychiatric comorbidity. RESULTS: We compared a group of 56 pilots with 94 other aircrew members. Results included 143 cases of flight phobia behavior and 7 cases of anxiety about parachuting. Flight phobia was less frequent among pilots (37.4%) than the other aircrew members (62.6%). We found a history of aircraft accident to the patient or an acquaintance in 25% of the cases. Observed comorbid psychiatric disorders (54%) consisted of depressive disorders (22%), anxiety disorders (16%), and personality disorders (7.4%). Fixed-wing pilots and aircrews members had a higher incidence of depression than did rotary-wing pilots and crewmembers (p < 0.05). Rotary-wing pilots and crewmembers had a higher rate of anxiety disorders (p < 0.05). DISCUSSION: Flight phobia encompasses a wide spectrum of clinical origins that may lead pilots or other aircrew members to refuse to fly. We recommend a careful psychiatric evaluation and close follow-up to adequately diagnose fliers with flight phobic reactions, as well as establishing adequate medical and/or psychological treatment.     

高性能飞机飞行员非冲击性颈部损伤的研究进展

概述了高性能飞机飞行员受高＋Gz所致非冲击性颈部损伤的研究进展，对预部损伤机理及类型进行了分析。指出了“检查6点钟”位置最容易引起颈部损伤。颈部损伤的症状可影响飞行员的飞行能力及日常生活，但经治疗后多可恢复飞行，只有少数严重损伤者需转飞其他机种。新型头颈支持系统、轻型头盔、以及颈肌强化锻炼有助于颈部损伤的预防。     

Off-duty preparation for overnight work in rotor wing air medical programs

INTRODUCTION: Air medical teams provide around-the-clock critical care, risking performance-altering fatigue from circadian disruption and sleep deprivation. Although safety is an essential issue in the air medical industry, there is little understanding of off-duty preparation for overnight shifts. METHODS: An anonymous survey was distributed to pilots and medical team members at participating programs with variable program, staffing, and shift models. Eighty responses from crewmembers working 12-hour night shifts (12N) were analyzed with appropriate t-tests and nonparametric tests. RESULTS: 12N crewmembers sleep significantly less in off-duty periods than before night shifts: 7.3 +/- 1.2 hours versus 4.8 +/- 1.9 hours (P < 0.01). Preshift sleep does not differ between crewmembers permitted on-duty rest and those for whom it is prohibited. 34.1% of 12N crewmembers permitted on-duty rest say they report to work planning to sleep. The minimum preshift sleep reported by 12N crewmembers before any shift in the past month averaged 2.4 +/- 2.3 hours, with 36.3% having worked overnight in the past month with no sleep before their shift On-duty rest permission was not a significant factor. Fifty-five percent of 12N crewmembers report outside employment (OE) in addition to their flight position. 12N crewmembers with OE averaged significantly less preshift sleep than those without OE: 4.4 +/- 2.1 hours versus 5.3 +/- 1.6 hours (P < 0.05). 54.5% of 12N crewmembers with OE described reporting to a flight shift within 8 hours of leaving their other job at least once within the past month. OE was more common when the flight program permitted on-duty rest (P < 0.01). CONCLUSION: Air medical team members report for 12N shifts with a significant sleep debt that does not differ between crewmembers permitted on-duty rest and those with on-duty rest prohibitions. More than half of flight team members surveyed have OE and many report for flight duty within 8 hours of leaving their other job. 12N shift crewmembers are at a particularly high risk for the consequences of fatigue. This is an important consideration as the industry develops on-duty rest guidelines to optimize safe operations.     

Space motion sickness during 24 flights of the space shuttle

The incidence and severity of Space Motion Sickness (SMS) were determined from 24 flights of the Space Shuttle. A standardized questionnaire developed at the NASA-Johnson Space Center (JSC) was administered to all crewmembers postflight during an oral debriefing with the examining flight surgeon. Cases of SMS were graded mild, moderate or severe using criteria developed at the JSC. The incidence of SMS during a first Shuttle flight for 85 crewmembers was 67% (57 cases). There were 26 mild cases (30%), 20 moderate (24%), and 11 severe (13%). Differences were found between males and females, crew positions (Commander, Pilot, Mission Specialist, etc.), and age groups, which were not statistically significant (p greater than 0.05), but would suggest future research into the mechanism, prevention, and treatment of SMS. The 26 crewmembers with a second flight showed a reduction in SMS incidence to 46%, but the change was not significant compared with the first flight. Nine crewmembers (35%) showed a reduction in SMS severity comparing first and second flights, yet there was no significant difference in the mean time between flights for crewmembers with SMS versus asymptomatic crewmembers. Variability in crewmember training and flight experience may explain some of the differences observed.     

Low back pain in Norwegian helicopter aircrew

The size and consequences of low back pain (LBP) in Norwegian helicopter aircrew has been investigated in a retrospective and prospective survey. With 50.5% reporting such pain in a 2-yr period, and Sea King aircrew reporting LBP on on almost half (49.3%) of the missions flown, the magnitude of the problem equals that reported from other air forces. Pilots reported LBP six times more often than other crewmembers and almost half (48.6%) felt the pain influenced the quality of work. This could have flight safety implications. Crewmembers with total flying time over 2,000 h have a significantly higher incidence of sick leave than those with less than 2,000 h. Only 1 pilot out of 10 with total flying time under 500 h had had flight-related LBP.     

民航飞行员先天性二叶式主动脉瓣畸形医学鉴定的探讨——附二例病例报告

目的 分析民航飞行员先天性二叶式主动脉瓣畸形的航空医学意义,探讨民用航空医学体检鉴定的政策、标准、方法和措施,提高体检鉴定水平.方法 报告2例民航飞行员先天性二叶式主动脉瓣畸形的临床资料,分析其发病特点;检索并借鉴国外航空医学的处置政策及具体方法,对我国民用航空医学的体检鉴定提出意见和建议.结果 确诊2例飞行员先天性二叶式主动脉瓣畸形,无任何临床症状,无明显血流动力学改变的临床证据,亦不具备介入和（或）手术治疗的临床指征.根据我国现行民航飞行人员体检鉴定标准,仅可按特许鉴定方案进行体检鉴定;两例飞行员特许鉴定合格后,分别恢复飞行3个月和13个月,飞行耐力良好,未见因医学原因出现的飞行事故或飞行事故征候.结论 民航飞行员先天性主动脉瓣畸形的航空医学评定应遵循个别评定、风险评估和谨慎的原则,若无症状、无血流动力学改变的临床证据、不具备介入治疗或手术治疗的指征等,总体风险水平在可接受范围内.在飞行员自我认识、密切航医监控、定期专科会诊的前提条件下可给予特许合格,或考虑授权航空体检医生进行协助特许体检鉴定.     

民航飞行员先天性二叶式主动脉瓣畸形医学鉴定的探讨——附二例病例报告

目的 分析民航飞行员先天性二叶式主动脉瓣畸形的航空医学意义,探讨民用航空医学体检鉴定的政策、标准、方法和措施,提高体检鉴定水平.方法 报告2例民航飞行员先天性二叶式主动脉瓣畸形的临床资料,分析其发病特点;检索并借鉴国外航空医学的处置政策及具体方法,对我国民用航空医学的体检鉴定提出意见和建议.结果 确诊2例飞行员先天性二叶式主动脉瓣畸形,无任何临床症状,无明显血流动力学改变的临床证据,亦不具备介入和(或)手术治疗的临床指征.根据我国现行民航飞行人员体检鉴定标准,仅可按特许鉴定方案进行体检鉴定;两例飞行员特许鉴定合格后,分别恢复飞行3个月和13个月,飞行耐力良好,未见因医学原因出现的飞行事故或飞行事故征候.结论 民航飞行员先天性主动脉瓣畸形的航空医学评定应遵循个别评定、风险评估和谨慎的原则,若无症状、无血流动力学改变的临床证据、不具备介入治疗或手术治疗的指征等,总体风险水平在可接受范围内.在飞行员自我认识、密切航医监控、定期专科会诊的前提条件下可给予特许合格,或考虑授权航空体检医生进行协助特许体检鉴定.     

模拟长航时飞行心理疲劳的对抗措施效果评价

目的评价模拟长航时飞行时心理疲劳的对抗措施的效果。方法16名男性飞行学员按抽签法随机分为对照组和试验组,在教-8飞行模拟器上进行8h的航线飞行。试验组施加心理疲劳对抗措施。通过模拟电码判译成绩、飞行成绩和焦虑自评量表（self-r ating anxiety scale,SAS）评分评价对比两组飞行学员的心理疲劳程度。结果随着飞行时间的增加,对照组的电码判译成绩、飞行成绩均显著下降（F=4．406、10．166,P=0．039、0．002）,试验组的两项成绩则均无显著下降（F=1．015、0．780,P=0．405、0．477）;对照组在飞行4h后,两项成绩与试验开始阶段相比差异有统计学意义（P〈0．05）,试验组的成绩则在飞行开始后的各时段间差异均无统计学意义（P〉0．05）。飞行前后,对照组的SAS得分无明显变化（t=1．032,P=0．329）;飞行后试验组的SAS得分则出现显著降低,与飞行前比较差异有统计学意义（t=3．222,P=0．010）。结论本研究采用的心理疲劳对抗措施对长航时飞行引起的心理疲劳现象有明显的对抗效果。     

不同飞行条件飞行员训练前后凝血及纤溶指标的对比研究

目的检测不同飞行条件下飞行员飞行训练前后凝血及纤溶指标的变化,以了解飞行训练对其凝血和纤溶平衡的影响。方法应用生物活性法和免疫比浊法,检测40名飞行员飞行训练前后的静脉血凝血酶原时间（prothrombin time,PT）、凝血酶时间（thrombin time,TT）、活化部分凝血活酶时间（activated partial thromboplastin time, APTT）、纤维蛋白原（fibrinogen,Fg）和D-二聚体（D-dimer,D-D）。依不同飞行强度（1次飞行和两次飞行）、不同飞行场次（昼航和跨昼夜飞行）、不同飞行载荷（＋3Gz和＋5Gz）、不同飞行高度（3km和5km）分别各分为两组。另设30名场站地勤人员为对照组。比较自身飞行训练前后,及不同组间凝血善F溶指标的差异。结果飞行前飞行员组与对照组凝血一纤溶指标的差异无统计学意义。飞行训练后PT、TT、APTT缩短、Fg、D-D升高,分别与飞行前自身及对照组比较,差异有统计学意义（t=2．925-6．908,P〈0．01）。完成各飞行课目后分别与飞行前比较,PT、TT、APTT缩短,Fg、D-D升高,差异有统计学意义（t=2．348-8．717,P％0．01或P〈0．05）。第1次飞行后与第2次飞行后、昼航与跨昼夜飞行后、3km与5km飞行后比较,凝血-纤溶指标的差异无统计学意义。＋5Gz飞行后与＋3Gz飞行后比较,TT缩短、Fg升高,差异有统计学意义（t=2．605、5．772,P=0．013、0．000）;其他指标差异无统计学意义。结论飞行员飞行训练后凝血与纤溶指标可发生改变,属于机体应激状态下的适应性反应。     

Factors determining geocentric orientation of pilots

The use of a rational (geocentric) method of orientation in flight is determined by the specific content of the conceptual model that develops in the course of flying experience and by the display of the spatial position of perceptive signs of the geocentric system of coordinates. The importance of these factors is confirmed by erroneous decisions made by operators with no flying experience (40%) when they estimated the spatial position as well as by a shorter time and a lower number of errors made in assessing the spatial position when the display presented signs of the geocentric system of coordinates.     

高性能战斗机飞行员仪表视觉空间定向能力训练效果观察

目的 探讨训练和提高飞行员仪表视觉空间定向能力的方法,并观察训练效果. 方法 对某部11名高性能战斗机飞行员分别进行仪表复杂状态的判断和操纵、平视仪复杂动作的判断和操纵、坚信仪表及坚信平视仪4个项目各5次的训练,在训练前后分别记录其判断反应时、操作正确率、飞机姿态偏差角和附加任务正确率等参数并进行比较. 结果 训练前后,仪表复杂状态判断的操纵判断反应时和操纵正确率分别为(1.42±0.24)s和(0.99±0.13)s、(53.91±9.12)%和(90.00±5.88)%;平视仪复杂状态判断的操纵判断反应时和操纵正确率分别为(1.54±0.29)s、(1.05±0.12)s、(73.09±12.02)%和(89.18±6.10)%;坚信仪表飞行姿态坡度偏差和俯仰角偏差分别为3.25°±0.60°和2.07°±0.25°、2.41°±0.63°和1.87°±0.30°;坚信平视仪飞行姿态坡度偏差和俯仰角偏差分别为3.08°±1.03°和2.06°±0.35°、2.84°±0.67°和1.99°±0.20°;坚信仪表和坚信平视仪飞行附加任务正确率分别为(63.90±11.15)%和(88.27±10.23)%、(59.73±12.81)%和(82.09±9.62)%.训练前后各参数比较差异均有统计学意义(t=2.47～11.03,P<0.01或P<0.05). 结论 通过飞行员仪表视觉空间定向能力训练可明显提高飞行员的仪表视觉空间定向能力水平. Abstract： Objective To explore effectiveness of improving the abilities of instrument visual spatial orientation (IVSO) training for high performance fighter pilots. Methods An IVSO training device was developed.Based on the principles of computer graphics and characteristics of cognition,4 kinds of instrument flight condition patterns were adopted as training profiles.Eleven pilots were trained along these four training profiles for five times,include recognizing and flying by instrument and head-up display respectively in complicated flight sortie or with interference.The reaction time,rate of correct operation,deviation angle of attitude and the adjunctive task completion rate were recorded and compared. Results In pre-and post-IVSO training,the reaction times got with instrument and head-up display in complicated flight sortie were (1.42±0.24)s vs.(0.99±0.13)s and(1.54±0.29)s vs.(1.05±0.12)s respectively while the rates of correct operations were 53.91%±9.12%vs.90.00%±5.88%and 73.09%±12.02%vs.89.18%±6.10% respectively.Deviation angles of roll and pitch in maintaining flight attitude by instrument training were 3.25°±0.60°vs.2.07°±0.25°and 2.41°±0.63°vs.1.87°±0.30°respectively,comparing to 3.08°±1.03°vs.2.06°±0.35°and 2.84°±0.67°vs.1.99°±0.20°in attitude maintenance by head-up display.Adjunctive task correct rates with believing instrument and head-up display were 63.90%±11.15%vs.88.27%±10.23%and 59.73%±12.81%vs.82.09%±9.62% respectively.All differences between pre-and post-IVSO trainings are statistically significant (t=2.47 to 11.03,P<0.01 or P<0.05). Conclusions The adopted instrument flight training can remarkably improve pilot's IVSO abilities.     

Human mononuclear cell function after 4 degrees C storage during 1-G and microgravity conditions of spaceflight

Future space missions of long duration may require that autologous leukocytes be stored in flight for infusion to restore normal immune competence in crewmembers. Peripheral blood mononuclear cells (PBMNCs), as leukocyte concentrates in autologous plasma and 2% dextrose, were stored in the microgravity conditions provided by the U.S. Space Shuttle Columbia (Mission 61-C). Activity of PBMNC after space flight was compared with that from a series of preflight ground control experiments, which demonstrated in culture a progressive daily loss in mitogen-stimulated protein synthesis at 24 h and thymidine uptake at 72 h after storage for 7 d at 4 degrees C. Post-storage viabilities were at least 90% as determined by trypan dye exclusion. A progressive reduction in the percentage of PBMNC expressing cell-surface phenotype markers, which was similar for monocytes, B cells, and T-cell subsets, also occurred after storage. The ability of PBMNC, stored for 8 d in Columbia's middeck, to become activated and proliferate in vitro was similar to that of cells that remained in identical flight lockers on the ground as 1-G controls, thus indicating that PBMNCs were not adversely affected by storage under microgravity conditions.     

Motion sickness in operational bomber crews

Airsickness has long been identified as a flying training issue. The present study sought to assess its impact in an operational setting. During a monthly wing safety meeting, 88 B-1B and B-52H crewmembers completed the "B-1B Airsickness Research File" questionnaire. The questionnaire responses were analyzed using ANOVA, Chi-square median tests, and multiple regression analyses. The percent of flights in which airsickness was experienced was found to be a function of crew position but not of aircraft type or the interaction of crew position and aircraft type. The degree of in-flight incapacitation experienced, however, was significantly predicted by the combination of crew position, aircraft type, and the amount of experience flying in bombers. Pilots reported the least amount of incapacitation, as did crewmembers who flew the B-1B and crewmembers with less bomber experience. Airsickness was reported to be a frequent occurrence among non-pilots in both aircraft. Experienced crewmembers were more likely to report an impact on their duties.