Analysis of information sources in references of the Wikipedia article "Skylark (rocket)" in English language version.
The original basic single-stage Skylark version used a Raven 1 motor (Rook derivative). The RPE Raven 1 burned 840 kg of propellant (ammonium perchlorate, polyisobutylene binder and aluminum powder) in thirty seconds with a 1450 kN total impulse at sea level.
After twenty-two launches in single-stage configuration, the first two-stage Skylark was launched in April 1960. The Cuckoo booster rocket used to accelerate Raven had the same diameter and raised the overall rocket height to 9.15m. It burned during approximately four seconds with a 364 kNs total impulse. This version of Skylark could launch a 150 kg payload to 200 km of altitude. The Skylark improvements continued in 1962, with the advent of Raven V (1780 kNs) loaded with a new propellant. However Raven II and VA engines were both available to meet different needs. Minor modifications led to VII and VIA versions respectively, then Raven VII loaded with Raven VI propellant became Raven VIII. In 1964, introduction of devices for payload attitude control was another kind of improvement for the Skylark rocket.
Over almost half a century a total of 441 Skylark rockets were launched, making it one of the longest and most successful programmes of its kind in the world.
The original basic single-stage Skylark version used a Raven 1 motor (Rook derivative). The RPE Raven 1 burned 840 kg of propellant (ammonium perchlorate, polyisobutylene binder and aluminum powder) in thirty seconds with a 1450 kN total impulse at sea level.
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