Ses 9 launch further delayed
SpaceX’s Falcon 9 rocket – forced to scrub its opening three attempts to launch the SES-9 communications satellite – will make another attempt on Friday evening. The mission will also involve a sporty attempt to recover the rocket’s first stage at sea via an Autonomous Spaceport Drone Ship. Liftoff will occur from SLC-40 at Cape Canaveral.
SES-9 Launch:
Wednesday’s opening attempt was delayed ahead of propellant loading due to unfavorable upper level winds.
The winds were deemed a problem for both fly out and onboard LOX temps for the rocket’s overall performance.
Thursday’s attempt managed to get under two minutes to launch, prior to a hold being called. Despite a long launch window, engineers opted to scrub for the day.
Based on the scrub rules for that point in the countdown, it was an automatic 48 hour turnaround. However, after a few days of evaluations, it was decided that Sunday will be the next launch attempt.
Sunday’s launch showed an increased ability with the hold rules as the countdown was once again halted just prior to launch. This time a ship in the Range was an issue. The launch team continued to hold the Falcon 9 until the ship was cleared.However, the launch was scrubbed when another hold was called – this time by the flight computer – during ignition of the Merlin 1D engines.
“Launch aborted on low thrust alarm,” noted SpaceX’s Elon Musk. “Rising oxygen temps due to hold for boat and helium bubble triggered alarm.”
The next launch attempt was to take place on Tuesday, following a data review of the abort that was conducted on Monday via a Delta Launch Readiness Review (DLRR). The 90 minute launch window was to open at 6:35pm Eastern.
However, due to projected high upper level winds, Elon Musk opted to move the launch to Friday night.
Link :
SES-9: SpaceX move to Friday launch option for Falcon 9 | NASASpaceFlight.com
SES-9 will be the eighth satellite launched by SpaceX in seven missions to geostationary transfer orbit – including the dual launch of the ABS-3A and Eutelsat 115 West B satellites last March.