On Monday, PanAmSat disclosed that its Galaxy IVR and PAS-6B satellites recently experienced anomalies with systems that maintain in-orbit positioning.

The problem is with propulsion systems on each satellite. A system unexpectedly shut down aboard Galaxy IVR in late June and aboard the PAS bird on July 9, the company disclosed in a Securities and Exchange Commission filing.

PanAmSat said it hasn't been able to restart the systems on each spacecraft, but the satellites are operating nominally on backup bi-propellant systems. If the spacecraft have to rely on the bi-propellant system, Galaxy IVR can do so for about three years and PAS-6B for four and a half years, PanAmSat said.

If it's determined that the propulsion systems have permanently failed on each satellite, PanAmSat said it may see an additional depreciation of about $4.5 million a month due to the technical problems.

The satellites are Boeing model 601 HP spacecraft. PanAmSat said there are seven of the Boeing models in its fleet.