1979-009A
The ECS (Experimental Communications Satellite) was built by Mitsubishi and Ford to carry out communications experiments in the UHF, SHF, submillimeter and millimeter bands. It was a spin stabilized cylinder with a mass of 130 kg (260 kg at launch), 0.93 m long (1.96m with antennas) and 1.41 m diameter. After launch ECS was named Ayame (`Iris'). Planned location was 145E.
ECS was based on the ETS-2 bus. Total mass of 260 kg was 139 kg ABM, 10 kg prop, and 111 kg dry satellite. Unfortunately, contact with ECS was lost 12 seconds into the apogee motor burn. The yaw weight (a 0.7 kg mass on a 1.8m wire) meant to tumble stage 3 did not deploy from stage 3, and stage 3 collided with ECS 37s after separation.
Element sets assigned to Ayame are misidentifications until 2005, when it was found in a 12669 x 34219 km x 9.9 deg orbit.
The Star 37 final stage was cataloged 20 years later, in 1999. The decayed second stage was retrospectively cataloged in 2000 but assigned to an old catalog number originally belonging to debris from the Magsat satellite; no TLEs are available.
A debris object in near-GTO was cataloged in 2008.
N-1 Stage 2 is 5860 kg full with 4740 kg prop, 1120 kg em, 53.35 kN thrust. (ISTS10-47), or 6032 kg full 5376 kg prop, 656 kg em (ActaAst7,967). Isp 285s or 290.2s (both values in AstraAc7,967). 250s burn time or: 4706f 1015 kg empty 5722 f (ISTS11-267). I take the latter, since it's a post-flight report of an actual mission.
Mass estimate: post stage 2 burn, 1015 kg + 669 + 260 = 1944 kg; 6645 kg f; if 290s then dV = 2844 ln ( 6645 / 1944) = 3500 m/s; for stage 3 burn 260 + (669/105).
| Ayame | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 1979 Feb 6 | 0846 | Launch by N-I | TNSC |
| T+3:45 St 1 MECO | |||
| T+3:54 Stage 1 sep | |||
| T+3:56 Stage 2 MES | |||
| 0850 | T+4? Fairing sep | ||
| 0854 | T+8:04 SECO Stage 2 cutoff, parking orbit | 200 x 300 x 30.4? | |
| Stage 2 | 171 x 192 x 30.43 (SSR) | ||
| 0911? | T+25m? Star 37 burn 37s | 606.8 191 x 34590 x 24.1 | |
| 0913 | Star 37 sep, failed to despin | ||
| 0914 | Star 37 collided with Ayame | ||
| 0914 | Ayame AKM and antennae damaged | ||
| 1979 Feb 6 | 1420? | Apo 1 | |
| 1930? | Peri 1 | ||
| 1979 Feb 7 | 0100? | Apo 2 | |
| 0530? | Peri 2 | ||
| 1130? | Apo 3 | ||
| 1530? | Peri 3 | ||
| 2100? | Apo 4 | ||
| 1979 Feb 8 | 0150? | Peri 4 | |
| 0800? | Apo 5 | ||
| 1130? | Peri 5 | ||
| 1800? | Apo 6 | ||
| 2200? | Peri 6 | ||
| 1979 Feb 9 | 0400? | Apo 7 | |
| 1979 Feb 9? | 0400? | AKM burn | |
| T+12s contact lost | |||
| 1979 Feb 9 | 0238 | Misid | 1500.01 36259 x 37797 x 0.5 |
| 1979 Jul 2 | Misid | 1351.28 31411 x 36808 x 0.5 | |
| 1979 Nov 19 | Misid | 1348.81 29749 x 38371 x 0.1 | |
| 1983 Dec 9 | Misid | 1314.48 28448 x 38293 x 0.3 | |
| 1990 Nov 18 | Misid | 1312.72 29268 x 37403 x 2.0 | |
| 1993 Dec 30 | Misid | 1312.99 29258 x 37423 x 4.9 | |
| 2005 Jan 12 | Found | 854.23 12669 x 34129 x 9.9 | |
| 2013 Aug 7 | 854.20 12673 x 34213 x 8.0 | ||
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