Lançamento do CBERS-3Segunda-feira, 09 de Dezembro de 2013 Às 11h26, hora de Beijing (1h26, hora de Brasília), desta segunda-feira (9/12), o satélite CBERS-3, desenvolvido conjuntamente por Brasil e China, foi lançado pelo veículo chinês Longa Marcha 4B, do Centro de Lançamentos de Satélites de Taiyuan, China. Porém, houve uma falha de funcionamento do veículo lançador durante o voo e, consequentemente, o satélite não foi posicionado na órbita prevista. Avaliações preliminares sugerem que o CBERS-3 tenha retornado ao planeta. Engenheiros chineses responsáveis pela construção do veículo lançador estão avaliando as causas do problema e o possível ponto de queda. Os dados obtidos mostram que os subsistemas do CBERS-3 funcionaram normalmente durante a tentativa de sua colocação em órbita. Para assegurar o cumprimento dos objetivos do programa CBERS, Brasil e China concordaram em iniciar imediatamente discussões técnicas visando a antecipação da montagem e lançamento do CBERS-4.
I made a rough estimate based on CBERS 2B and an 11s shortfall in the burn and 720 km apogee.I get an orbit around -153 x 720 km x 98.5 deg, with impact in the Antarctic around 0407 UTC.However, the uncertainties are large.
Quote from: jcm on 12/09/2013 09:05 pmI made a rough estimate based on CBERS 2B and an 11s shortfall in the burn and 720 km apogee.I get an orbit around -153 x 720 km x 98.5 deg, with impact in the Antarctic around 0407 UTC.However, the uncertainties are large.I was skeptical at first, since this third stage is supposed to burn for more than 6 minutes, but it turns out that 11 seconds is all it takes with this relatively heavy payload to fall short - way short. Something like 270 meters/second short, give or take. - Ed Kyle
According to INPE (quoted by Globo), the cause of the failure was a premature cutoff of the 3rd stage engine 11 seconds earlier than nominalThe altitude reached was 720 km instead of 778 km planned. The velocity reached was not enough to maintain an orbital flight(source in Portuguese: http://g1.globo.com/sp/vale-do-paraiba-regiao/noticia/2013/12/corte-antecipado-na-propulsao-impediu-cbers-3-de-manter-orbita-diz-inpe.html)
The story of the failure as experienced by a reporter with the Brazilian delegation attending the launch(in Portuguese): http://www.blogdaretrato.com.br/2013/12/rb-na-china-o-fracasso-do-lancamento-do.html
Any launch pics in the offing..?
Hmm there are reports that the rocket used on this launch has been stored for several years already (in fact someone said that it's CZ-4B s/n Y10), and it might already been in Taiyuan since late last year. Long storage issues maybe?
Quote from: input~2 on 12/10/2013 03:11 pmThe story of the failure as experienced by a reporter with the Brazilian delegation attending the launch(in Portuguese): http://www.blogdaretrato.com.br/2013/12/rb-na-china-o-fracasso-do-lancamento-do.html AIUI, that post seems to imply that satellite separation happened... even though the stage didn't achieve orbit. I guess that's possible - and may even have been programmed - if your U/S doesn't have restart capability, then there' nothing you lose by triggering satellite sep through a timer linked to engine cut-off? (Yeah, maybe RCS can give you some dV, but it's nothing the satellite couldn't do on its own..?)
Infantile behaviour, revealing true colors of a prison-state...if we don't publish launch pics it didn't happen.