# Lambda (rocket family)

Lambda is the name of a series of Japanese carrier rockets. It consisted of the types Lambda 2, LSC-3, Lambda 3, Lambda 3H, Lambda 4S, Lambda 4SC, and Lambda 4T developed jointly by Institute of Industrial Science of the University of Tokyo, Institute of Space and Astronautical Science of the University of Tokyo, and Prince Motor Company, which merged with Nissan in 1966.
Lambda series rockets did not have guidance systems, as they had the potential to be converted for offensive military use, thus interpreted as a violation of Article 9 of the Japanese Constitution. However, future Japanese launch vehicles, such as the H-II, were allowed to have guidance systems.

## Configurations

Lambda types differ regarding the upper stages used. The following table shows the actual configurations:
| Type | Boosters | Stage 1 | Stage 2 | Stage 3 | Stage 4 |
| Lambda 2 | - | L-735 | K-420 | - | - |
| Lambda 3 | - | L-735 | K-420 | Kappa-8 | - |
| Lambda 3H | - | L-735 | L-735(1/3) | L-500 | - |
| Lambda 4S | 2 × SB-310 | L-735 | L-735(1/3) | L-500 | L-480S |
| Lambda 4SC | 2 × SB-310 | L-735 | L-735(1/3) | L-500 | L-480S |
| Lambda 4T | 2 × SB-310 | L-735 | L-735(1/3) | L-500 | L-480S |

## Launches

Lambda rockets were launched by ISAS, from Kagoshima pad L.
On February 11, 1970, the first Japanese satellite Ohsumi was launched using a Lambda 4S rocket.
The Lambda 4S was launched nine times, though five were failures. The first launch of the Lambda 4S rocket took place on September 26, 1966, from Kagoshima. A fourth-stage attitude control failed resulting in loss of the vehicle and payload.
List of Lambda launches :
| Date | Version | Apogee (km) | Mission |
| 1963 August 24 | Lambda 2 | 51 | Failure |
| 1963 December 11 | Lambda 2 | 410 | Ionosphere mission |
| 1964 July 11 | Lambda 3 | 857 | Ionosphere mission |
| 1965 January 31 | Lambda 3 | 1040 | Ionosphere mission |
| 1965 March 18 | Lambda 3 | 1085 | X-ray astronomy mission |
| 1966 March 5 | Lambda 3H | 1829 | X-ray astronomy mission |
| 1966 July 23 | Lambda 3H | 1800 | Gyro-plasma probe Ionosphere / aeronomy mission |
| 1966 September 26 | Lambda 4S | 400 | Ohsumi launch attempt. Failure: Fourth stage attitude control failed |
| 1966 December 20 | Lambda 4S | 400 | Ohsumi launch attempt. Failure: Fourth stage failed to ignite |
| 1967 February 6 | Lambda 3H | 2150 | Ionosphere / chemical release / x-ray astronomy mission |
| 1967 April 13 | Lambda 4S | 200 | Ohsumi launch attempt. Failure: Fourth stage failed to ignite |
| 1969 January 16 | Lambda 3H | 1800 | Ionosphere mission |
| 1969 September 3 | Lambda 4T | 400 | Test mission |
| 1969 September 22 | Lambda 4S | 400 | Ohsumi launch attempt. Failure: Fourth stage control system malfunction after third stage collided with fourth stage |
| 1970 January 21 | Lambda 3H | 1848 | Ionosphere / plasma mission |
| 1970 February 11 | Lambda 4S | 2440 | Ohsumi (first successful satellite of Japan, fifth attempt of Lambda 4S) |
| 1970 September 19 | Lambda 3H | 2017 | X-ray / ultraviolet astronomy mission |
| 1971 August 20 | Lambda 4SC | 1500 | Failure |
| 1971 September 3 | Lambda 3H | 1718 | Aeronomy / ionosphere / x-ray astronomy mission |
| 1973 January 28 | Lambda 4SC | 1500 | TVC test |
| 1974 January 22 | Lambda 3H | 1571 | St 2: 329 km X-ray astronomy mission |
| 1974 September 1 | Lambda 4SC | 1500 | TVC test |
| 1976 August 30 | Lambda 4SC | 1500 | Radar transponder |
| 1977 August 16 | Lambda 3H | 1294 | Aeronomy / ionosphere / plasma mission |
| 1979 September 20 | Lambda 4SC | 82 | TVC test |