RLA variants

The basic configuration of the RLA rockets was a common core stage complemented by a different number of standard first-stage strap-on boosters, depending on the mass of the payload. Very little has been revealed about the RLA launch vehicles studied in 1974-1975 and various sources have also given different designators for rockets with similar capabilities. Apparently, the design evolved significantly even during that short period, dictated by the progress made in the concurrent research on kerosene/hydrocarbon and hydrogen engines. It would appear that original plans for large clusters of low-thrust engines eventually gave way to small clusters of high-thrust engines as the confidence in the latter grew.

Glushko is known to have presented plans for three RLA rockets (RLA-120,135, and 150) during a meeting on 13 August 1974, which was attended by most of the chief designers and also by Dmitriy Ustinov. This was Glushko’s third RLA proposal in the barely three months he had been in office at NPO Energiya. The August 1974 RLA plans revolved around the exclusive use of kerosene and sintin, the 1,003-ton thrust RD-150 engine, and massive 6m diameter rocket modules. The RLA-120, expected to be ready in 1979, would have a payload capacity of about 30 tons and among other things launch modules of a permanent space station. The RLA-135 had a 100-ton payload capacity and could be used to orbit a reusable space shuttle or

elements of a lunar base and was expected to make its debut in 1980. Finally, there was the massive RLA-150, capable of placing up to 250 tons into low orbit and seen by Glushko as the rocket that would eventually send Soviet cosmonauts to Mars. Its first flight was anticipated in 1982 [48].

Other sources have identified three rockets known as RLA-110 or Groza (“Thunderstorm”), RLA-120 or Grom (“Thunder”), and RLA-130 or Vulkan (“Vol­cano”). The RLA-110, equipped with two boosters, would have a payload capacity “higher than the Proton rocket”. The RLA-120, using four boosters, would have about the same payload capacity as the N-1. Finally, the RLA-130, toting eight boosters, would play a key role in establishing a Soviet lunar base [49].

While Glushko’s RLA plan may have looked very appealing on paper, upon closer analysis it did raise the necessary questions among fellow designers. Some warned that because of the unification not all the launch vehicles in the series would be the most efficient in their particular payload class. The design of the common core stage had to be tailored to the heaviest 250-ton class booster, which was the one expected to fly least. The implication was that the core stage was oversize for the 30-ton class RLA, exactly the one that would probably be launched most frequently [50]. This is probably the very reason preference was eventually given to Yuzhnoye’s 11K37 “heavy Zenit’’ to fill this niche in the payload spectrum. Some felt that a better way of developing a standardized rocket fleet was to first fly a light booster, then use its first stage as the second stage for a heavier booster, subsequently turn that second stage into a third stage for an even heavier rocket, etc. [51]. This was the approach that Korolyov and Chelomey had suggested for their respective N-I/N-II/N-III and UR-200/UR-500/UR-700 families in the 1960s. One big disadvantage, however, was that each vehicle in the fleet would require its own launch pad.

In the end, the only rocket that emerged from the RLA plans was the 100-ton class booster that later became known as Energiya. Proposals were later tabled for Energiya derivatives such as Energiya-M (30-ton class), Groza (60-ton class), and Vulkan (200-ton class), but these never made it off the ground (see Chapter 8). And so the dream of a standardized rocket fleet in the heavy to super-heavy class never materialized either, although the main reason here was the absence of payloads to justify its existence.