If you’ve been following the most recent space news, you probably already know that Elon Musk’s SpaceX is at the forefront of commercial rocket launches. Accordng to a report from Space.com, however, even the leading spaceflight company faces significant challenges getting its rockets off the ground.

SpaceX recently aborted the launch of a commercial satellite with less than a second to go before liftoff on February 28. According to company officials, the SES-9 satellite was slated for launch from the Cape Canaveral Air Force Station in Florida at 6:46 p.m. on Sunday evening. Unfortunately, a boat entered the mission’s “keep-out-zone” and the launch was called pushed back 35 minutes.

As the final countdown approached, the Falcon 9 rocket’s engines fired up but suddenly shut down after the low-thrust alarm was triggered. Elon Musk blamed rising oxygen temperatures and a helium bubble for triggering the alarm and cancelling the launch.

The SES-9 mission also included plans to land the Falcon 9’s first stage back on Earth for a soft landing. This marks the third time the mission has been pushed back, with launch attempts also taking place on Wednesday and Thursday of last week.

According to Falcon 9 product director John Insprucker, “We don’t have another launch planned at the moment. We’re going to have to continue to evaluate the first-stage telemetry that we have. The Falcon 9 is safe; the vehicle went through a standard recovery sequence that we’ve used many times.”

The original plan was for the Flacon 9 to deliver the communications satellite SES-9 into geostationary orbit for one of SpaceX’s big clients, Luxembourg-based SES. In addition to delivering the satellite into orbit, the mission provided another opportunity for engineers to successfully land a rocket on a drone-ship. They have tried to accomplish this numerous times before, and while recent attempts have landed on-target, each time the rocket crashed over and exploded upon landing.

An overview of the SES-9 Mission can be found here.