Long March 3B delivers satellite to wrong orbit

In the rocket’s first anomaly since 2009, a Long March 3B failed to deliver a commercial Chinese television commsat to the correct geosynchronous transfer orbit.  The first two stages of the flight were normal, but for reasons not yet clear, the third stage did not reach the desired target orbit before releasing the payload.  The payload itself, Chinasat 9A, has deployed its solar arrays and is healthy, and controllers on the ground are assessing options for salvaging its mission.  Depending on how far off they are from the target orbit, it may be possible to gradually raise the orbit using its maneuvering thrusters.

This has been done with other geosynchronous commsats whose launch vehicles suffered similar anomalies, most famously the first USAF AEHF satellite.  In that case, the launch vehicle performed flawlessly, but AEHF-1 was equipped with an apogee kick motor to deliver it to geosynchronous transfer orbit; this failed to ignite, stranding it in the initial parking orbit.  An agonizingly slow orbit raise was performed using the tiny Hall thrusters on the spacecraft, eventually successfully raising it to the proper orbit for its mission.  It is unclear at this point whether a similar salvage will be possible for Chinasat 9A, but it’s definitely worth exploring.  That said, preliminary radar data suggests the spacecraft is in an orbit inclined 25.7 degrees (instead of the 0 degrees that’s intended), with an apogee of 16, 360 km and a perigee of just 193 km — skimming the atmosphere, basically, which will rob it of precious energy each time it goes around, giving very little time to begin a recovery plan (if one is even possible).  It’s very likely this spacecraft is lost, unfortunately, a reminder of how difficult spaceflight still is.

However, the initial part of the launch was as beautiful as one would expect of a rocket launch, although perhaps due to the third stage anomaly, I have been unable to find a longer video:


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