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Aviation History
1961
1961 - 0515.PDF
FLIGHT, 20 April 1961 523 •net by our Soviet people. I was moved to tears by NikitaSergey-ich Khrushchev's telegram. . ." * * * The first "Cosmonaut" is aged 27—the US Astronauts are nowiged between 34 and 40—and initially was a pattern-moulder and •'oundryman by trade, graduating with distinction from the Lyubertsyartisans school near Moscow. Later he went to a technical college in Saratov, and then to a military aviation college at Orenberg.He is married to a medical graduate he met in Orenberg, and has two daughters, Elena and Galina. According to Prof Blagonravovbe was a parachute instructor at Smolensk before being picked for Cosmonaut training.Small chinks of light were permitted to escape through the black-velvet curtain shrouding Soviet spacecraft when Sovnewsissued, on April 12, the text of a brief essay on The First Manned Space Flight: Problems of Fuel, Precision and Re-entry, by ProfIgor Merkulov. It read as follows: ""A spaceship designed for manned flight must meet stringentscientific and engineering requirements. This is particularly true of the means of propulsion and the instrumentation; that is, theautomatic and telemetric systems for accurate orbiting and control of the ship in flight. Fuel "To place a body in orbit round the Earth, it has toreceive more than 3m tonne-metres [21,699m ft-lb—Ed.] of kinetic energy for every tonne [2,2051b] of its weight. The Soviet space-ship weighed nearly four and three-quarter tonnes. What does this mean in terms of actual energy? To perform enough workto get a spaceship into orbit would take a man handling heavy loads seven hours a day about 2,000 years. The rocket enginesmust do that work in a matter of minutes. These figures show the importance of choosing the correct fuel for the rocket engines. '"A second fuel problem is that of packing the greatest possibleamount of fuel into the lightest possible containers. The weight of the fuel is more than one hundred times greater than the weight ofthe ship finally placed in orbit.* Thus multi-stage carrier rockets must accommodate hundreds of tons of fuel, with their dead-weightremaining as small as possible. Precision "The launching of the rocket carrying the spacevehicle requires great precision. In an orbit such as that flown by Yuri Gagarin, for instance, an error of 1° in direction or oneper cent in speed could bring the ship back into the dense layers of the atmosphere on its very first orbit, and it would burn up. Re-entry "In the three-and-a-half years since the launching ofthe first Sputnik, scientists all over the world have been discussing the vital question of re-entry. So far there is only one successfulmethod of slowing down for re-entry. "The braking motor [retro-rocket] is aligned so that, when theengine is switched on, the thrust is in the opposite direction to the ship's movement. In this way the thrust brakes the vehicle. Thiscalls for a lot of additional fuel. "The theory of rocket flight provides exact figures of fuel expen- * A high figure, suggesting a relatively low specific impulse; it impliesa total launch weight of some 500 tons. SPACE TRAVELLERS Date 3.11.57 13.12.58 28.5.59 2.7.59 10.7.59 15.5.60 19.8.60 13.10.60 1.12.60 31.1.61 9.3.61 25.3.61 12.4.61 Nation USSR USA USA USSR USSR USSR USSR USA USSR USA USSR USSR USSR Objective Recovery from orbit Ballistic shoe (Jupiter C) Ballistic shot (Jupiter) Ballistic shot Ballistic shot Recovery from orbit Recovery from orbit Ballistic shot (Atlas) Recovery from orbit Ballisticshot (Mercury) Recovery from orbit Recovery from orbit Recovery from orbit Pay load Dog Laika Squirrel monkey Two rhesus monkeys Two dogs, one rabbit Two dogs Life capsule, dummy man Two dogs, plus other specimens Three mice, RVX-2A vehicle Two dogs, other speci- mens Chimpanzee Dog, guinea pigs, etc. Dog, other specimens Man Result No recovery No recovery Success Success Success No recovery Success Success No recovery Success Success Success Success Note: The US Project Mercury schedule originally called for a manned ballistic (Redstone) shot in May I960. In our most recent account of the programme (issue of December »2 last) we gave January as the expected date: today it is put at "April 28 at the earliest." A Mercury orbit is likely late this year. diture for specific acceleration or deceleration—theoretically thereis no difference between the two. For instance, to effect a change of speed of about 300ft/sec. the amount of fuel used would be fromthree to four per cent of the payload. To reduce the speed by about 3,000ft/sec. the fuel required would be about 30 per cent of thepayload, while to halve the speed would require almost four- fifths of the payload. Together with the fuel tanks and motor, thismakes up some 90 per cent—leaving only one-tenth of the payload for the passenger and cabin. "Estimates and experience show that the deceleration requiredfor de-orbiting and safe re-entry is comparatively small, but if the ship should enter the dense layers of the atmosphere at near-cosmicspeeds it would disintegrate like a meteorite. Landing "Re-entry and safe landing pose many problems.A large amount of fuel has to be burnt to brake the vehicle and guide it safely through the atmosphere. But the slower the speed isreduced, the greater is the heat from friction, and the more cumber- some do the ceramic [our italics] heat shield and cooling system haveto be. The engineer's task, therefore, is to produce a vehicle which ensures the lowest possible weight for all elements of the landinggear—the braking motors, fuel tanks, heat protection system, and soon. "One method is the almost complete braking of the spaceshipand then its parachuting to Earth, as is done with the geophysical rockets. The fuel expenditure for this, however, would be toogreat—so great in fact that it would take a multi-stage rocket to decelerate the ship, and that would bring down the weight of thepassenger cabin to less than one per cent of the total payload. It has been found that the best results can be achieved by a com-bination of power deceleration with atmospheric drag, where parachute or wings [our italics] can be used." There is no reason to doubt the authenticity of these two photographs, which were issued by Toss on April 16. The Russian caption to the picture on the left states that Gagarin is seen waving to the launch crew before entering the lift which carried him up the side of the huge boost rocket to the space capsule probably more than 100ft above. The smaller illustration, which shows details of his pressure helmet and what appears to be either microphones or the nipples of his liquid/solid feeding system, was made as he rode to the launch pad in a lowly bus
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