N-II (rocket)
The N-II rocket | |
| Function | Carrier rocket |
|---|---|
| Manufacturer | McDonnell Douglas (design) Mitsubishi Heavy Industries (production) |
| Country of origin | United States (design) Japan (production) |
| Size | |
| Height | 35 metres (115 ft) |
| Diameter | 2.44 metres (8.0 ft) |
| Mass | 132,690 kilograms (292,530 lb) |
| Stages | 2 or 3 |
| Capacity | |
| Payload to LEO | |
| Mass | 2,000 kilograms (4,400 lb) |
| Payload to GTO | |
| Mass | 730 kilograms (1,610 lb) |
| Associated rockets | |
| Family | Delta |
| Launch history | |
| Status | Retired |
| Launch sites | Tanegashima, Osaki |
| Total launches | 8 |
| Success(es) | 8 |
| First flight | 11 February 1981 |
| Last flight | 19 February 1987 |
| Boosters – Castor 2 | |
| No. boosters | 9 |
| Powered by | 1 TX-354-3 |
| Maximum thrust | 258.9 kilonewtons (58,200 lbf) |
| Specific impulse | 262 sec |
| Burn time | 37 seconds |
| Propellant | Solid |
| First stage – Thor-ELT | |
| Powered by | 1 MB-3-3 |
| Maximum thrust | 866.7 kilonewtons (194,800 lbf) |
| Specific impulse | 290 sec |
| Burn time | 270 seconds |
| Propellant | RP-1/LOX |
| Second stage – Delta-F | |
| Powered by | 1 AJ-10-118F |
| Maximum thrust | 41.3 kilonewtons (9,300 lbf) |
| Specific impulse | 280 sec |
| Burn time | 335 seconds |
| Propellant | HNO3/UDMH |
| Third stage (optional) – Star-37E | |
| Powered by | 1 solid |
| Maximum thrust | 68 kilonewtons (15,000 lbf) |
| Specific impulse | 284 sec |
| Burn time | 42 seconds |
| Propellant | Solid |
| Third stage (alternative, optional) – Burner-2 | |
| Powered by | 1 solid |
| Maximum thrust | 43.6 kilonewtons (9,800 lbf) |
| Specific impulse | 285 sec |
| Burn time | 42 seconds |
| Propellant | Solid |
The N-II or N-2 was a derivative of the American Delta rocket, produced under licence in Japan. It replaced the N-I-rocket in Japanese use. It used a Thor-ELT first stage, a Delta-F second stage, nine Castor SRMs, and on most flights either a Star-37E or Burner-2 upper stage, identical to the US Delta 0100 series configurations. Eight were launched between 1981 and 1987, before it was replaced by the H-I, which featured Japanese-produced upper stages. All eight launches were successful.