Medical Problems Of High-Speed Flight

Press, Volume XCIX, Issue 29366, 19 November 1960, Page 10

Medical Problems Of High-Speed Flight

IBv GRAHAM KING]

It seems obvious to think of the great airliners that ply the sky routes of the globe mainly as the handiwork of an army of engineers and technicians. But as aircraft get bigger and machines are .being prepared to fly passengers faster than sound, a new expert is being called into the design team. He is the doctor. His arrival signals the end of the era when the solution to most of the medical problems of flying airline passengers lay in a packet of airsick pills. Almost overnight what experts dub “passenger tolerance” has become the most crucial question-mark in civil aviation.

With jet and rocket power, with new metals, with electronics, and with greatly advanced knowledge in aerodynamics, no-one doubts that planes can be built to go several times faster than existing speeds. That they can be built to go thousands of feet higher is a recognised fact. Attention to Passengers

But now tlie men behind the scene are pausing to glance up from their drawing-boards and rivet guns. Their attention is focusing upon the ordinary men and women who are supposed to fly in the machines they build. It is becoming evident that through all the stages of future aircraft the embryo science of aviation medicine will play a vital role. A new kind of flying doctor will be consulted to check just what passengers will accept—and whether it will do them any damage./ Even in today’s comparatively slow aircraft, passengers sometimes undergo odd effects. Experts estimate that it takes three months for a traveller to unwind completely after a non-stop eighthour jet flight Tests conducted at Cambridge University have told doctors a great deal about the end results of prolonged confinement aboard aircraft. Reactions Vary Individuals vary in their reactions to these circumstances. Passengers described by researchers as “inert” show a flagging of interest, fatigue and excessive boredom. “Overactive” subjects have to fight against violent urges to run up and down the aisle or perform hand-stands as mental and physical compensation for having to sit still so long. As time passes, brain and body function deteriorates from smooth co-ordinated activity to indifferent, erratic behaviour. With these effects come side-sensations of restlessness, irritability, daydreaming, and a pathological attention to bodily needs.

It seems that these reactions are due to what doctors call sensory deprivation. Starved of the stimulus of an earthbound environment, travellers get unreasonably edgy and hyper-criticaL Air hostesses are trained to watch for such symptoms on long flights. This is one reason why many airlines insist on passengers being bombarded with food, coffee and magazines. In extreme cases, really neurotic passengers have been known to get hysterical or display all the symptoms of drunkenness—without having touched a drop of alcohol.

Doctors believe that passenger stress will be the trickiest problem which will have to be designed out of supersonic aircraft. A typical—and not infrequent—horror of present-day passengers is disorientation due to cloud or darkness. Nervous travellers have reported suffering vivid sensations of' nose-diving towards the ground while in fact the plane is flying straight and level. Doctors fear this phobia might affect perfectly normal passengers flying in the supersonic airliners being visualised. No Cabin Windows

Blueprints show that windowless cabins will be necessary because of aerodynamics and pressurisation requirements of such flight. The envisaged aircraft would take off at an agle of 12 degrees from the horizontal. To the passenger strapped in a seat already tilted against G-forces, it might seem as acute as 30 degrees. After take-off, the machine would climb to a cruising altitude of 63,000 ft—nearly 12 miles high. Speeds might reach 2000 or 3000 m.p.h.

One soothing device being considered is’ a television screen mounted in the passenger compartment to show scenic views or other artificial vistas. This way. it is hoped to allay fear, worry or anxiety. But even if it

works out, many other problems dare expert solution. Among them is what airline operators know as “the time factor.”

An aircraft cruising at Mach 2.2 (about 1450 m.p.h.) would leave London at 9 a.m. and arrive in New York at 7 a.m. local time—two hours before take-off.

Apart from metabolic upsets like having to eat two breakfasts, there are other more serious complications involved. One biological effect has already been noted by medical officers checking H-bomber crews on longrange missions.' This is that shuttling between different climates and tinie zones at high speeds sets up urinary variations when the kidneys get out of gear. Much equipment of the aircraft of the future will have to pass critical medical tests before it !S fitted. A crucial unit will be the air-conditioning plant for withdrawing vapour from the cabin at the same rate it is being generated by occupants. Difficulty of Heat It must be foolproof. Medical

scientists calculate that in a temperature of 74 degrees Fahrenheit, with no water removed, the atmosphere in a 120-seater aircraft would be saturated in 15 minutes. A further' formidable barrier to faster passenger flight is the tremendous power of heat-fric-tion. An unprotected airliner slicing through the air at 2000 m.p.h. would pressure-cook passengers and crew in minutes. Engineers can overcome this grim prospect by refrigerating the cabin and perhaps also insulating the fuselage with a double skin. These devices are certain to be made fail-proof before the maiden flight of the first faster than sound airliner.

But before any passenger steps aboard, doctors will have solved physical and mental headaches as enormous as any mechanical trouble-shooters are likely to strike.—(Central Press. All rights reserved).