Guerre di meraviglie

SEVEN miles above the earth a man-made cloud of vapor, 50 feet wide and miles long, was stringing out behind the Lockheed P-38, up for a high-altitude test. In the plane’s cockpit Milo Burcham lifted his eyes from the whirlwind dance of four pith balls in a small transparent cage and reached for the radio microphone. He spoke as rapidly as he could: “Burcham in YP-38. 35,000.” He made his message short and he didn’t sign off as he was supposed to, because he was too exhausted. At 35,000 feet a pilot dare not interrupt his breathing for long and even the few words that Burcham spoke robbed him of a whiff of precious oxygen. Another sentence might have killed him. Starved of oxygen, he might have passed out and possibly suffocated, or the plane might have gone into a screaming dive from which Burcham would not have had time to pull out after he finally regained consciousness at a lower altitude. Man is literally a fish out of water in the stratosphere. He must keep warm against the 60 degrees below zero cold that he may encounter, Gases in his system expand four times normal volume and he suffers excruciating pains unless he has chewed charcoal tablets ahead of time. He has to supercharge himself before he leaves the ground to avoid the dangerous “bends” during his fast climb and after he has landed again he breathes a helium-oxygen mixture to relieve the head pains caused by the rapid changes of pressure. A cigaret won't burn at 35,000 feet, so low is the oxygen content of the thin air, and the pilot has to breathe bottled oxygen while he is aloft. If moisture in the oxygen freezes, if the supply becomes exhausted, or a line plugs, the pilot dies. That’s why, to Burcham, the most important instrument in the cockpit is the small Lucite cage that contains the bouncing pith balls. As long as the balls keep dancing, Burcham knows that oxygen is passing through his homemade flow meter and that he can continue to breathe. A few pilots have climbed higher than 35,000 feet in special airplanes built for setting records. Instead of trying to create records Burcham is going about the prosaic business of learning what a modern military airplane, ready for action, will do at high altitudes and what the effect is on the pilot. Up in the thin air where the speeding wings sometimes leave clouds of condensed water vapor trailing behind and where the pilot’s reactions are slowed down, even a slight exertion may cause him to collapse. The work of recording the readings of the numerous dials on the instrument board is turned over to an automatic camera that takes a picture every 15 seconds. Breathing oxygen, a pilot can fly at 25,000 feet in comparative safety because at that altitude his reactions are close to normal and he is not too high above the safe breathing level. Two miles higher and safety is more critical. Before Burcham was ready to test the Lockheed interceptor he spent some time in Rochester, gaining high altitude experience in the Mayo Clinic’s low pressure chamber. One fest that Burcham set for himself was to simulate bailing out of a disabled plane at 35,000 feet. In the low pressure chamber he rapidly disconnected his oxygen tube and raised his hands to pretend that he was sliding back the transparent cockpit cover of his imaginary airplane. That's as far as he got. At once the watchful attendants outside the chamber valved in enough air to bring him back to consciousness. Burcham had discovered that if a pilot has to leave his plane at 35,000 feet he will never have a chance to pull his ripcord unless he first switches his breathing mask to a portable bottle of oxygen and carries the bottle with him over the side. Pilots can’t fight at 35,000 feet, not because the planes don’t handle well at that altitude but because the pilots themselves are slow. In a dogfight the pilots would wander all over the sky and do little damage to each other. But, cruising up against their ceilings, the pilots are still very valuable because from there they can watch for oncoming bombers and dive down to intercept them, recovering strength and ability as they descend. If pilots are ever to fight at the seven mile level or are called upon to go still higher for guard duty, they will have to fly in supercharged cabins that give them the pressure of lower altitudes. Air liners of the future will fly in the stratosphere because of the tremendous boost in speed that thin air permits. The planes will be equipped with pressure cabins and Trans- continental and Western Air has already made the first step in this direction with its supercharged Boeing stratoliners. The first military experiments with a high-altitude pressure cabin were conducted in a special “leakproof” transport plane that Lockheed built for the Army Air Corps several years ago. The twin-motored P-38, in level flight in the stratosphere, is reported to have flown faster than any airplane ever flew before although its actual speed is a military secret. Several hundred of the single-seat interceptor pursuits are being built for the Army Air Corps and nearly 1,000 of the export model have been ordered by Great Britain. To be at all useful in high altitude maneuvers, pilots have to be supercharged before they leave the ground and the suggestion is that when the new planes are put in active service their pilots will remain on call in a decompression room where they breathe pure oxygen. Half an hour is required to supercharge a pilot so that he can climb rapidly and be at his best at a high fighting altitude. In the past, pilots were pretty well supercharged by the time they reached 30,000 feet because the planes they flew climbed slowly. Rapid ascent in a fast-climbing modern plane releases nitrogen bubbles in the bloodstream the same as happens to a deep sea diver who ascends to the surface too rapidly. Divers call it the “bends” and it can produce temporary paralysis or unconsciousness. In aviation it is avoided by “supercharging” the pilot before the climb by having the pilot breathe pure oxygen long enough for the nitrogen content of his blood to be reduced to a safe point. The pilot, wearing a nose breathing mask attached to the oxygen supply, exercises mildly while he is being supercharged by riding a stationary bicycle. After half an hour of treatment he disconnects his breathing tube from the main oxygen tank, connects it to a portable tank that he carries under his arm, and continues to breathe pure oxygen as he walks over to the plane. Once in the cockpit he attaches his tube to the plane’s oxygen supply and he is ready to take off.