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Aviation History
1962
1962 - 1030.PDF
1028 FLIGHT International, 28 June 1962 APOGEE ts 400s«c 2nd-STAGE SEPARATION 3rd-STAGE IGNITION 3rd-STAGE Vt • 8.713 mp.h/ n *33* 2nd-STAGE BURNOUT t-130.5 sec 1st-STAGE Above, launch trajectory for Diamant, which is expected to place a French scientific satellite in orbit by 1965 Left, general arrangement of the three-stage Diamant launch vehicle, with dimensions in inches Missiles and Spaceflight a project due to restriction of funds, or the restarting of a project which has been stopped, demands a much greater expenditure than the original sum in order to achieve the end result—since others will probably have advanced in the interval and the learning period must be recommenced. "The formulation of a good policy and the rapid decision to implement it, with sufficient funds for it to progress with all speed, is our need today; and it is the responsibility of all of us here to put pressure upon our respective governments to achieve this end. "Further, if no strong and virile European space effort is initiated in the near future, there is an evident danger that the aerospace industries will lose essential scientific and technical personnel; and the new generation of these vital people will have to find their future elsewhere—perhaps not in Europe . . . "While I have said much that is obvious, I have deliberately done SO because I feel strongly that any further delay in getting Western Europe into space, and the very limited scope of present official programmes, will merely waste funds and achieve nothing worth while. "We of the SFA and BIS and Eurospace have shown that it is possible to collaborate and work together amicably, so let us there fore present a united front to our governments—but above all make our proposals so attractive to the official mind that it is persuaded, without pain, to give willing support, whether for new and advanced projects or to give material help to the space effort of the United States of America. "Such a combined effort could put the free Western nations in an unassailable position in all fields of space exploration." One of the most interesting technical papers presented at the meeting was the description of the French Diamant launch vehicle given by M R Chevalier, technical director of SEREB. Extracts from this paper, and points from a number of other contributions to the meeting, are given below. Diamant Briefly discussed in our June 14 issue, Diamant (Dia mond) is the three-stage light/medium satellite launcher planned by the French for their own national space programme. Now in the project-design stage at the Societe pour l'Etude et la Realisation d'Engins Ballistiques, it is considered to merit serious consideration on account of its simplicity and relatively low cost. In fact M Cheva lier described it at Paris as "possibly indispensible ... to the countries of Europe." First stage of Diamant has a single chamber, gimballed about two axes at right angles, giving a sea-level thrust of the order of 28 tonnes (61,7301b). Propellants are white fuming nitric acid and "essence de terebenthine" (turpentine), fed by pressurizing the steel tanks by means of a solid-fuel gas generator in the top of the upper (acid) tank. The total of approximately 27,5601b of propel lants is burnt in 88sec. On the skirt are mounted four fins, two of which are driven by the first-stage autopilot to provide roll control. Weight of the first stage is 31,3101b, of which 3,7501b is structure. Propulsion of the second stage is effected by a single 5,0161b cast filling of a polyurefhane fuel called Isolane, housed in a case of 40 CDV 20 (Vascojet 1,000) steel and discharged through four nozzles each providing thrust vector control about one axis. Thrust of some 33,0701b is maintained for about 42 seconds. Separation of the second stage is effected by a system of solid-fuel rams. The second stage weighs 6,3931b, of which 1,3771b is structure. Isolane is also employed in the third stage, but in this case the 1,4331b charge is contained in a glass-fibre-wound case and dis charged through a single fixed nozzle. Thrust may be varied between 5,290 and 11,6851b, and combustion time is approximately 47 sec onds. The third stage is joined to the second by articulated arms, jettisoned at the moment of separation. The stage weighs 1,7641b, of which 3111b is structure. One of the illustrations depicts a typical flight-plan for a satellite launching. Liftoff is vertical, but as soon as lOOm/sec velocity is reached a gende tilt is induced according to a trimming programme which holds incidence near zero during first-and second-stage combustion. First-stage burnout occurs at 88sec, and the second stage ignites as the powder jacks effect separation. A "few moments" later the command is given to jettison the fairing which protects the payload and third stage during the climb through the denser layers of the atmosphere. Following 2nd-stage burnout, the second and third stages are tilted down by means of a nitrogen-jet system until their axis is parallel to the horizontal at the top of the ballistic trajectory. As soon as the desired attitude is stabilized, the vehicle is spun about its longitudinal axis by means of small tangential rocket units Separation of the second stage and its attached equipment bay then takes place by means of retrorockets and pivoting arms. As soon as the third stage and payload reach the apogee of the intermediate ballistic trajectory following 2nd-stage burnout, the 3rd-stage motor is ignited, die precise timing being so chosen that, at the instant of 3rd-stage burnout, the fall of the trajectory has been nullified (i.e.,
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