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At least 127 records · Page 7Linked to original sources
PubMed1999

The psychological cost of aircraft noise for children.

Psychological effects of aircraft noise exposure on children have only recently been addressed in the References. The current study took advantage of a natural experiment caused by the opening of a major new airport, exposing children in a formerly quiet area to aircraft noise. In this prospective longitudinal investigation, which employed non-exposed control groups, effects of aircraft noise prior to and subsequent to inauguration of the new airport as well as effects of chronic noise and its reduction at the old airport (6 and 18 month post relocation), were studied in 326 children aged 9 to 13 years. The psychological health of children was investigated with a standardized quality of life scale as well as with a motivational measure derived from the Glass and Singer stress aftereffects paradigm. In addition a self report noise annoyance scale was used. In the children studied at the two airports over three time points, results showed a significant decrease of total quality of life 18 month after aircraft noise exposure as well as a motivational deficits operationalized by fewer attempts to solve insoluble puzzles in the new airport area. Parallel shifts in children's attributions for failure were also noted. At the old airport parallel impairments were present before the airport relocation but subsided there after. These findings are in accord with reports of impaired psychological health after noise exposure and indicate the relevance of monitoring psychological parameters as a function of environmental stressors among children.

Adolescent↗
PubMed2000

Aircraft control forces and EMG activity: comparison of novice and experienced pilots during simulated rolls, loops and turns.

BACKGROUND: Flying an aircraft requires a considerable degree of coordination, particularly during aerobatic activities such as rolls, loops and turns. Only one previous study has examined the magnitude of muscle activity required to fly an aircraft, and that was restricted to takeoff and landing maneuvers. The aim of this study was to examine the phasing of muscle activation and control forces of novice and experienced pilots during more complex simulated flight maneuvers. METHODS: There were 12 experienced and 9 novice pilots who were tested on an Aermacchi flight simulator while performing a randomized set of rolling, looping, and turning maneuvers. Four different runaway trim settings were used to increase the difficulty of the turns (elevator-up, elevator-down, aileron-left, and aileron-right). Variables recorded included aircraft attitude, pilot applied forces, and electromyographic (EMG) activity. Discriminant function analysis was used to distinguish between novice and experienced pilots. RESULTS: Over all maneuvers, 70% of pilots were correctly classified as novice or experienced. Better levels of classification were achieved when maneuvers were analyzed individually (67-91%), although the maneuvers that required the greatest force application, elevator-up turns, were unable to discriminate between novice and experienced pilots. There were no differences in the phasing of muscle activity between experienced and novice pilots. The only consistent difference in EMG activity between novice and experienced pilots was the reduced EMG activity in the wrist extensors of experienced pilots (p < 0.05). The increased wrist extensor activity of the novice pilots is indicative of a distal control strategy, whereby distal muscles with smaller motor units are used to perform a task that requires precise control. Muscle activity sensors could be used to detect the onset of high G maneuvers prior to any change in aircraft attitude and control G-suit inflation accordingly.

Adolescent↗
PubMed2001

The effect of aircraft control forces on pilot performance during instrument landings in a flight simulator.

BACKGROUND: Pilots may have difficulty controlling aircraft at both high and low force levels due to larger variability in force production at these force levels. The aim of this study was to measure the force variability and landing performance of pilots during an instrument landing in a flight simulator. METHODS: There were 12 pilots who were tested while performing 5 instrument landings in a flight simulator, each of which required different control force inputs. Pilots can produce the least force when pushing the control column to the right, therefore the force levels for the landings were set relative to each pilot's maximum aileron-right force. The force levels for the landings were 90%, 60%, and 30% of maximal aileron-right force, normal force, and 25% of normal force. Variables recorded included electromyographic activity (EMG), aircraft control forces, aircraft attitude, perceived exertion and deviation from glide slope and heading. Multivariate analysis of variance was used to test for differences between landings. RESULTS: Pilots were least accurate in landing performance during the landing at 90% of maximal force (p < 0.05). There was also a trend toward decreased landing performance during the landing at 25% of normal force. Pilots were more variable in force production during the landings at 60% and 90% of maximal force (p < 0.05). CONCLUSION: Pilots are less accurate at performing instrument landings when control forces are high due to the increased variability of force production. The increase in variability at high force levels is most likely associated with motor unit recruitment, rather than rate coding. Aircraft designers need to consider the reduction in pilot performance at high force levels, as well as pilot strength limits when specifying new standards.

Adult↗
PubMed2003

In-flight medical events and aircraft diversions: one airline's experience.

BACKGROUND: An aging population combined with the increasing mobility of people with acute and chronic illnesses could make an increase in the frequency of in-flight medical events aboard commercial aircraft likely. OBJECTIVE: To determine the incidence of each type of in-flight medical complaint, the appropriateness of medical kit contents, which factors lead to aircraft diversion, and which factors effect the appropriateness of the decision to divert. METHOD: Medical complaints reported aboard a sample airline from July 1, 1999 through June 30, 2000 were studied. The frequency of aircraft diversion was related to complaint and medical assistance provided. The appropriateness of the decision to divert was determined as a function of hospital admission rates. RESULTS: There was an incidence of 22.6 medical complaints per million passengers and 0.1 deaths per million passengers. There were 210 diversions per million flights with one of every 12.6 incidents resulting in a diversion. When a passenger volunteer was used, they opened the medical kit 62% of the time. When a physician participated in the decision to divert the hospital admission rate was 49% versus 15% with no physician input. CONCLUSION: Variations in incidence of medical complaints cited in previous studies demonstrate the need for an industry-wide standardized reporting method of in-flight medical events. All in-flight medical complaints could likely have been adequately treated with the contents of the FM's newly mandated medical kits. Physician participation in decisions to divert aircraft should be sought as it is associated with more appropriate divert decisions.

Aerospace Medicine↗
PubMed2003

In-flight hypoxia incidents in military aircraft: causes and implications for training.

BACKGROUND: Hypoxia has long been recognized as a significant physiological threat at altitude. Aircrew have traditionally been trained to recognize the symptoms of hypoxia using hypobaric chamber training at simulated altitudes of 25,000 ft or more. The aim of this study was to analyze incidents of hypoxia reported to the Directorate of Flying Safety of the Australian Defence Force (DFS-ADF) for the period 1990-2001, as no previous analysis of these incidents has been undertaken. The data will be useful in planning future training strategies for aircrew in aviation physiology. METHOD: A search was requested of the DFS-ADF database, for all Aircraft Safety Occurrence Reports (ASOR) listing hypoxia as a factor. These cases were reviewed and the following data analyzed: aircraft type, number of persons on board (POB), number of hypoxic POB, any fatalities, whether the victims were trained or untrained as aircrew, if the symptoms were recognized as hypoxia, symptoms experienced, the altitude at which the incident occurred, and the likely cause. RESULTS: During the period studied. 27 reports of hypoxia were filed, involving 29 aircrew. In only two cases was consciousness lost, and one of these resulted in a fatality. Most incidents (85.1%) occurred in fighter or training aircraft with aircrew who use oxygen equipment routinely. The majority of symptoms occurred between 10,000 and 19,000 ft. The most common cause of hypoxia (63%) in these aircraft was the failure of the mask or regulator, or a mask leak. Rapid accidental decompression did not feature as a cause of hypoxia. Symptoms were subtle and often involved cognitive impairment or light-headedness. The vast majority (75.8%) of these episodes were recognized by the aircrew themselves, reinforcing the importance and benefit of hypoxia training. CONCLUSION: This study confirms the importance and effectiveness of hypoxia training for aircrew. Hypoxia incidents occur most commonly at altitudes less than 19,000 ft. This should be emphasized to aircrew, whose expectation may be that it is only a problem of high altitude. Proper fitting of masks, leak checks, and equipment checks should be taught to all aircrew and reinforced regularly. Current hypobaric chamber training methods should be reviewed for relevance to the most at-risk aircrew population. Methods that can simulate subtle incapacitation while wearing oxygen equipment should be explored. Hypoxia in flight still remains a serious threat to aviators, and can result in fatalities.

Adult↗
PubMed1976

Study of the microbiological environment within long- and medium-range Canadian Forces aircraft.

Because of a possible requirement to carry patients with highly virulent communicable diseases, a study was undertaken to observe smoke patterns within Canadian Forces transport aircraft. This was followed by the quantitative evaluation of the spread on non-pathogenic organisms disseminated within a Boeing 707 and a C13OE (Hercules). Thirdly, an attempt to recover respiratory tract viruses during transatlantic flights was made. Smoke patterns showed that an infected patient should be placed at the rear of the aircraft. The spread of the nonpathogenic organisms in a 707 indicated that contamination was largely confined to the rear, except when the aircraft was in an unpressurized mode. In the C13OE, contamination was shown to occur throughout the whole aircraft. No respiratory tract viruses were recovered during the transatlantic flights. It is essential that a 707 should be utilized for aeromedical evacuations. If a C13OE is being considered, then a portable self-contained isolation care unit is mandatory.

Aerospace Medicine↗
PubMedDate not supplied

Children's cognition and aircraft noise exposure at home--the West London Schools Study.

The association of aircraft noise exposure with cognitive performance was examined by means of a cross-sectional field survey. Two hundred thirty six children attending 10 primary schools around Heathrow Airport in west London were tested on reading comprehension, immediate/delayed recall and sustained attention. In order to obtain the information about their background, a questionnaire was delivered to the parents and 163 answers were collected. Logistic regression models were used to assess performance on the cognitive tests in relation to aircraft noise exposure at home and possible individual and school level confounding factors. A significant dose-response relationship was found between aircraft noise exposure at home and performance on memory tests of immediate/delayed recall. However there was no strong association with the other cognitive outcomes. These results suggest that aircraft noise exposure at home may affect children's memory.

Aircraft↗
PubMed2005

Depressurization in military aircraft: rates, rapidity, and health effects for 1055 incidents.

INTRODUCTION: Aircraft cabin depressurization is a rare event but one which demands attention because of the grave potential for aircrew incapacity in flight. The purpose of the current study was to determine rates of depressurization incidents for U.S. military aircraft, to examine their causes, and to evaluate the medical importance of these incidents. METHODS: The U.S. Navy and U.S. Air Force safety center databases were searched for decompression incidents during FY1981-FY2003. A total of 1055 incidents were analyzed as to the cause, speed of onset, and adverse health effects (hypoxia, barotrauma, DCS, or any combination of these). The causes of each incident were identified and classified by aircraft type. RESULTS: The number of incidents per airframe varied from 1 (in many airframes) to 276 in the T-38. The number of total hours flown ranged from 16,332 in the T-6 to 8,101,607 in the C-130. The number of sorties flown ranged from 8800 in the B-2 to 3,543,061 in the C-130. Of 35 common airframes, 30 showed rates between 0 and 20 incidents per million flying hours. Depressurization was "slow" in 83% of incidents. Of the 1055 incidents, only 350 (33.2%) involved adverse health effects. Hypoxia occurred in 221 incidents, DCS in 83, and barotrauma in 71. Only 4 (0.4%) resulted in a fatality. Of the 199 incidents involving hypoxia, 12 (6%) occurred below 4267 m (14,000 ft). CONCLUSION: Most reported military aircraft depressurization incidents are slow and do not affect aircrew health. Rates have decreased dramatically since the 1980s. Still, this study lends support to continuing hypobaric chamber training for military pilots.

Aerospace Medicine↗
PubMed1992

Evaluation of ground ambulance, rotor-wing, and fixed-wing aircraft services.

It is hoped that this article has offered insightful suggestions and criteria in choosing the most appropriate method to transport patients. Ground ambulances, rotor-wing, and fixed-wing aircraft each have advantages and disadvantages in particular circumstances. The advantages and disadvantages of any mode of transport must be considered to best meet the needs of the patient. In the twentieth century alone, great strides have been made in the field of emergency stabilization and transport. An efficient, well-trained ground ambulance program remains the backbone of prehospital and interhospital transport systems. Helicopters and fixed-wing transports must be integrated into the EMS system. One advantage of the helicopter and fixed-wing aircraft is rapid travel times when time is critical. As Hicks et al said, "early resuscitation and timely transfer of selected patients are critical factors in reducing morbidity and mortality." The future holds many possibilities for enhanced patient transport. Hospitals may be able to use tilt-rotor, vertical landing, fixed-wing aircraft to combine the advantages of helicopter and fixed-wing aircraft. After all, our primary goal is to get the right patient, with the right personnel, to the right place in the right amount of time.

Aircraft↗
PubMed1990

A case of G-LOC in a propeller aircraft.

The occurrence of +Gz-induced loss of consciousness (G-LOC) is well recognized in high-performance aircraft. A case of G-LOC is described involving a co-pilot on a flying instructor's course in a propeller-driven aircraft, the CT-4. The cause of G-LOC is attributed to a combination of a lack of recent G exposure, not commanding the aircraft, fatigue, and a possibly less-than-optimal straining manoeuvre. This case reinforces the problems of G-LOC in any aircraft capable of performing aerobatics.

Adult↗
PubMed1988

[Aircraft noise: changes in biochemical parameters].

The effect of stress caused by aircraft noise was studied on 14 female and 11 male volunteers, who were of a age ranging from 21 to 42 years and of a mean age of 25 years. The volunteers were exposed to an aircraft simulator that stimulated the low level flight of an air force plane and produced a maximum noise level of 105 dB(A) for 3 sec. in a short time. Before and immediately after the exposure, the concentration of ACTH was measured by means of a radioimmunoassay. The ACTH is a hormone, responsible for initiating a chain reaction that is characteristic for a stress reaction. In 100% of the cases the concentration of this hormone increased. It reached a pathological level in 28% of the cases. The effect on the lipid metabolism was expressed by an increase of total cholesterol and a decrease of the triglycerides in the serum. A slight increase in blood sugar which, together with the free fatty acids, is relatively quickly reduced to energy, could be determined. The aircraft noise did not influence the activity of the liver transaminases in any way. A short-term exposure to aircraft noise is able to stimulate a stress reaction, whereby, the determination of the ACTH offers valuable informations.

Adrenocorticotropic Hormone↗
PubMed1985

Disease-bearing insects brought in by international aircraft into Singapore.

Fifty-seven (17.3%) of 330 incoming aircraft landing at Changi International Airport were found to harbour mosquitoes and other insects on board. The frequency of insects detected in aircraft from the Southeast Asian countries varied from 7.1% to 32.2%. Live insects were found in 5 (6.1%) of 82 aircraft disinsectized by the "block away" method. The species of mosquitoes brought in were: Culex quinquefasciatus (96), Culex tritaeniorhynchus (1), Aedes albopictus (2) and Aedes aegypti (1). None of the 51 female Culex quinquefasciatus dissected was found to be infected with microfilariae. They key to the prevention of introduction of exotic vectors and transmission of vector- borne diseases is to continue with the existing system of vector surveillance and control at the international airport, rather than routine disinsecting of aircraft landing in Singapore.

Aircraft↗
PubMed1987

+Gz-induced loss of consciousness and aircraft recovery.

Aircrew incapacitation resulting from very high onset sustained +Gz stress has resulted in significant losses of aircraft and aircrew. Enhanced protection and training toward prevention of +Gz-induced loss of consciousness (G-LOC) will continue to be vital. Techniques for reduction of the time of incapacitation, should G-LOC occur, must also be explored and developed. Current capability of aircraft autorecovery as demonstrated by the Advanced Fighter Technology Integration F-16 (AFTI/F-16) promises to enhance safety from the acute incapacitation resulting from G-LOC (and spatial disorientation). Physiologic monitoring for determining G-LOC has certain advantages especially in the aerial combat arena. The optimum physiologic monitoring technique would be direct determination of failure of brain cell function at the cellular or subcellular level. Complete investigation of G-LOC is necessary to understand the phenomenon and to develop methods for enhancing recognition and recovery. This paper discusses aircraft autorecovery technology and potential methods for physiologic monitoring of G-LOC. Integration of physiologic monitoring techniques into aircraft autorecovery systems requires a broad approach for optimal development.

Aerospace Medicine↗
PubMed1985

Passive smoking in aircraft--a current WHO project.

Only few measurements of levels of pollution by tobacco smoke in aircraft have been made. The results suggest that levels are quite moderate, but studies of actual reactions by passengers and cabin crew indicate rather strong, objective effects. These consist of irritation of the mucous membranes of eye, nose and throat as well as perception of bad odours. Evidently, environmental tobacco smoke causes distress in aircraft already at lower concentrations than under ground conditions, probably because of special climatic conditions such as ultra-low air humidity, elevated levels of ozone, subnormal air pressure and, eventually, disturbance of the concentration of light air ions. None of these abnormalities can easily be eliminated. Ventilation, however effective in terms of rate of air changes, can not effectively curb local peak concentrations, and, close to a smoker the concentration of smoke may be 100 times as high as the room average. Therefore, aircraft must provide separate smoking resp non-smoking areas. Area division along an aisle is unacceptable since the ventilation system makes the aisle and adjacent seats on both sides be located in one whirl of common air. WHO will try to stimulate improvements of airline practices and aircraft design.

Aircraft↗
PubMed1972

Worldwide studies on aircraft disinsection at "blocks away".

During 1971 worldwide experiments on the disinsection of passenger cabins at "blocks away" (as the aircraft starts taxiing for take-off) were conducted in several types of jet aircraft. A procedure was developed whereby the high capacity Boeing 747 could be disinsected by four stewardesses in less than 1 minute. The favourable results of these and previous trials indicate that this method is suitable as a standard procedure for aircraft disinsection for international quarantine purposes.The biological effectiveness against resistant and non-resistant mosquitos of a 2% concentration of a pyrethroid, resmethrin, in Freon 11+Freon 12 (1:1) (without kerosine) and a favourable passenger response make it suitable as a standard formulation for aircraft disinsection.

Aedes↗
PubMed1982

Improving the crashworthiness of general aviation aircraft by crash injury investigations.

An aircraft accident investigation program correlates injuries to occupants with the severity of impacts and structural changes in the crash. Findings brought to the attention of aircraft manufacturers have led to specific aircraft being made more crash-worthy. The finding of a failure in a shoulder harness attachment led to the strengthening of the attachment brace. The way a shoulder harness was joined to a lapbelt was modified following a noted failure. The finding of fractures of lapbelt and shoulder harness cable tiedowns led to the use of stronger cables and modification of the installation. Other findings resulted in a shoulder strap guide being placed on an inertia reel and a side-mounted seat being modified. Described also are three seat-related features which, although meeting FAA standards, during the dynamics of a crash may lack desirable energy attenuation. These findings illustrate the value of aircraft crash injury correlations.

Accidents, Aviation↗
PubMed1982

Fitts' principles still applicable: computer monitoring of fighter aircraft emergencies.

When examining the impact of automation in the cockpit, a careful distinction must be drawn between the role of a multi-crew civilian aircraft and a single-seat military aircraft. For the former, there are some concerns that automation can have a negative impact on the crew by reducing their proficiency. However, for a single-seat military aircraft on an attack mission, the role of automation is not only helpful to the pilot now but in the future may be necessary to achieve mission success. These distinctions must constantly be brought to mind in explaining the concepts of Fitts' principles. For a single-seat military aircraft, it is believed that these principles still apply, and that computer monitoring of system failures will further enhance their application. Three approaches to computer-augmented system monitoring are discussed.

Aerospace Medicine↗
PubMed1995

Deaths and injuries as a result of lightning strikes to aircraft.

Aircraft are at risk of being struck by lightning or triggering lightning as they fly through clouds. Commercial and private airplanes have been struck, with resultant deaths and injuries to passengers and crew. We were interested in learning how large a problem existed to the American public from lightning strikes to airplanes. We analyzed data from the National Transportation Safety Board (NTSB) on lightning-related accidents in the United States from 1963-89. NTSB recorded 40 lightning-related aircraft accidents. There were 10 commercial airplane accidents reported, 4 of which were associated with 260 fatalities and 28 serious injuries. There were 30 private aircraft accidents that accounted for 30 fatalities and 46 serious injuries. While lightning remains a potential risk to aircraft passengers and crew, modern airplanes are better equipped to lessen the dangers of accidents due to lightning.

Accidents, Aviation↗