Tansei 3

 1977-012A

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Tansei-3 (MS-T3) was the test payload for the Mu-3H prototype flight. Mass was 128 kg plus 56 kg kick motor. Size is 0.93m dia 0.80m high; 1.38m long with kick motor, KM-A thrust is 7.0 kN , Isp 283s. Launch was 71 deg elevation and 152 deg azimuth. The Mu-3H had a larger first stage than the earlier models.

The payload included a 0.38m dia kick motor which raised the orbit at first apogee. The kick motor was installed `upside-down' on top of the satellite at launch. Tansei 3 had a spin rate of 2.1 rev per second in parking orbit, maintaining its attitude for half a revolution. Kick motor fired half an orbit after insertion above S America increasing speed by about 750 m/s into a 136 minute orbit.

On the first rev visibile from Kagoshima, the first yo-yo system is fired to decrease spin rate from 120 to 40 rpm. A cold gas jet propulsion test was tried but a valve malfunction caused problems. Then, a second yo-yo system was used to further despin the satellite and activate the magnetic spabilization.

Stage 3+4 was 1436 kg full 351 empty, 67 kN., 53 s burn time. Without St 4, 1249f 164em. Isp 284s. Stage 4 was 187 kg full 141 kg empty including satellite, 20s burn time, 6.8 kN, KM-A is 59f 13? em., Isp 281s.

Tansei 3
Date	Time	Event	Orbit
1977 Feb 19	0515:00	Launch by Mu 3H-1	KASC
		T+0:08 SOB burnout
		T+0:09 SOB sep
	0516?	T+1:24 St 1 burnout	-6228 x 95 x 58.3
		T+1:26 B2 ig
	0517?	St 2 burnout
	0517?	Fairing top off
	0517?	Fairing lower part off
	0520?	T+6:00Spinup St 3	-5366 x 331 x 62.5 (p344)
	0521	T+6:02 St 2 sep	-4451 x 328 x 65.5
	0521:05	St 2 apo
	0521	T+6:07 St 3 burn, 54s
	0522	St 3 burnout
	0522:57	T+7:57 St 3 sep	95.9 329 x 793 x 65.5
		T+7:57 Yo ig
			327 x 825 x 65.64 (ISASB)
	0607:58	Activate damping?
	0609:39	T+54:40 KM Kick motor burn, 20s
	0610:00	KM burnout
	0611:20	T+56:20 KM sep	134.3 796 x 3821 x 65.8
		T+56:20 Yo-yo despin
		Boom deploy
		T+1 week? Second yo-yo despin

Payload:

• MAG Magnetic attitude control system (test for EXOS-A)

• JET Cold-gas jet for spin axis control
• MAG-EXT Mag stabilization booms, 2m long

• Yo-yo system

• UVP Auroral UV photometer test