Figure 2.7. The conventional path for launcher development is the adaptation of a military ballistic missile (SS-6 "Sapwood") to a space launcher. "Sputnik" is an almost unmodified SS-6. "Soyuz" is a very capable, very reliable space launcher with hundreds of launches (over 90 per year).

Figure 2.7. The conventional path for launcher development is the adaptation of a military ballistic missile (SS-6 "Sapwood") to a space launcher. "Sputnik" is an almost unmodified SS-6. "Soyuz" is a very capable, very reliable space launcher with hundreds of launches (over 90 per year).

ballistic trajectory. The USAF Titan ICBM became the mainstay of the McDonnell Douglas Gemini manned spacecraft program. The McDonnell Douglas Delta launcher began its career as the Unites States Air Force Thor IRBM. The Thor core continues to serve even now, as the Boeing Delta II and Delta III launchers. The Convair Atlas launcher began as the USAF Atlas ICBM, and was the launcher that put John Glenn into the first US astronaut Earth orbit in the Mercury capsule. It keeps on living today, with Russian-derived RD-170 rocket engines, as the Atlas V. Even in Europe, ESA launchers have an industrial rocket hardware base to build on that is military-derived (e.g., the future VEGA launching system).

In fact, in order to begin, this was about the only alternative in existence. What it did, though, was to instill an operational concept of the expendable system as the most cost-effective approach, and with its low launch rate, to assure a continuing manufacturing base. Consider, for instance, the consequences if the first launchers were capable of just 10 launches before overhaul. In the early years, that might have meant only one or two launchers being fabricated, instead of 20. The aircraft scenario was different because there were customers for all of the DC-3s that could be built, and literally hundreds of thousands of potential and actual passengers. For space activities to change, there has to develop a similar customer base requiring hundreds of flights per year, rather than eight to twelve.

In this context, the former USSR came the closest. When one of the authors visited Baikonur in 1990, the civil Soyuz launch complex had launched 90 Soyuz in the previous 1-year period. The launch and countdown was based on a military counter-strike philosophy. There were about seven Soyuz and Soyuz payload in active storage. These could be launched in about 12 hours. On the day the author witnessed the Soyuz launch, the Soyuz arrived, transported horizontally on a train, at about 05:30 h. By 07:00 h the Progress spacecraft (Progress is a Soyuz manned capsule reconfigured as a propellant and materials re-supply vehicle) was horizontally integrated into the Soyuz launcher. It was then taken by rail to the launch site and erected. After 10:00 h the propellant loading and countdown of the Soyuz launcher was executed by a neural network system of computers. The computer system "remembered" the Soyuz launch history over its several hundred launches. If any feature in the countdown matched a previous problem or potential problem, a service crew was sent to the launch pad to check the launcher. During this checking time the countdown continued, with only the item in question on hold. When the item status was confirmed as "OK" that item was re-inserted into the count. According to the Soviet Launching Officer on site, only one in fourteen launches have holds past the scheduled launch time for more than 15 minutes. The Soyuz and Progress capsule was launched at 17:05 h that afternoon (Figure 2.8). In spite of the accomplishments of the Soyuz program, it remained an expendable launcher [Karashtin et al., 1990].

The heaviest lift launcher available in the former USSR was the Proton. The Proton was the result of an uncompleted intercontinental ballistic missile program. The Proton is powered by a hypergolic propellant rocket engine, the RD-253, in a unique arrangement. That is, a central larger diameter oxidizer tank is surrounded by six smaller fuel tanks, each with an RD-253 engine installed, as shown in

Liftoff 17:05 Arrival 05:30

Figure 2.8. ''Soyuz'' launch with ''Progress'' re-supply capsule at 17:05 h in April 1991 from Baikonur Space Center, Tyuratam, Kazakhstan (Photo by the author).

Figure 2.8. ''Soyuz'' launch with ''Progress'' re-supply capsule at 17:05 h in April 1991 from Baikonur Space Center, Tyuratam, Kazakhstan (Photo by the author).

Figure 2.9. Proton first stage in Moscow plant.

Figure 2.9. The hypergolic propellant driven turbopumps start up so abruptly, that the sound is almost like an explosion! The launcher is one of the more reliable launchers available for heavier payloads, but like Soyuz, it is completely expendable. The Proton continues to be produced today, offered as a reliable heavy-lift launcher by a consortium that includes Lockheed Martin. It was an important element in the construction of the International Space Station. The Russian space organization wanted a launcher that was recoverable, that was reusable, and that was capable of heavy lift to orbit for a spectrum of missions, going from the support of facilities in LEO to deep-space missions [Gubanov, 1984]. With the United States initiation of the "Star Wars'' space defense program (SDIO) and the Space Shuttle, the Soviet military was convinced they needed to counter a new military threat. They perceived (correctly) "Star Wars'' as a system to destroy their warheads and warhead delivery systems. But they also perceived the Space Shuttle program as a disguise to create a direct attack, fractional orbit ''Space Bomber''. This perception would merge into what was to produce eventually the fully reusable heavy-lift vehicle ''Energia'' and the fully automatic military space plane "Buran". By whatever method of calculation, the Soviets concluded that the Space Shuttle initiative was sufficiently important to build seven vehicles [Legostayev, 1984]. After NASA fielded the three operational shuttles, the Soviets were convinced that ''the missing four'' were hidden someplace, ready to launch at the Soviet Union in a manner similar to the ICBMs in missile silos [Lozino-Lozinski, 1986]. In fact, strange as it may seem, it was reported that just seven Buran airframes were fabricated, in a tit-for-tat response to the US shuttle program [Lozino-Lozinski, 1990]. Buran was derived from Lozino-Lozinski's work on the ''BOR'' series of hypersonic gliders that began in the 1960s, analogous to the Unites States Air Force Flight Dynamics Laboratory efforts [Buck et al., 1975]. According to Lozinski, he had launched at least 24 test vehicles of the BOR family using scrapped ballistic missile stages. The United States Air Force Flight Dynamics Laboratory had launched several ''Asset'' hypersonic glider test vehicles in the 1960s, but that is the limit of the US experience [Buck et al., 1975; Hallion, 2005].

The result of these Russian efforts was a heavy launcher capable of launching either cargo or a spacecraft to space that was fully recoverable in its operational form. In its principal operational version, "Energia" was equipped with a side-mounted cylindrical cargo carrier that could be configured as a heavy-lift package to LEO, or a satellite to GSO, a payload to be delivered to the Moon or Mars, and a deep space probe. Unlike the United States Shuttle, the primary propulsion engines were mounted on the center main tank not on the space plane. Because of the emphasis on astronauts the US Space Shuttle evolved into a design that can never be flown without astronauts, the Shuttle has no heavy-lift canister or heavy-lift capability. The author drew Figure 2.10 during a lengthy discussion with Boris Gubanov at a Space Conference in Bonn, Germany, in 1984. This figure clearly shows the concept of operation. There were few disposable parts. The side canister could be configured with just sufficient propulsion to reach LEO, or with sufficient propulsion (and less payload) for a Moon, Mars or a deep-space mission. The Zenit-based strap-on boosters were equipped with lifting parasail parachutes at the front and rear of the booster. The intent was to glide in the vicinity of the launch site for recovery. Since the boosters were liquid boosters (equipped with Energomash RD-180 rocket engines), there was little refurbishment, unlike the US solid propel-lant strap-on boosters. These solid boosters cost as much to refurbish as to build

Core and payload carrier

Conical < caps

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