GREENBELT, Md. — Orbital Sciences Corp. continues to have problems on a money-losing Earth observation satellite contract inherited from General Dynamics Corp. that is at the center of a legal dispute between the companies.

The Landsat Data Continuity Mission (LDCM) contract with NASA became Orbital’s by virtue of its 2010 acquisition of General Dynamics’ Gilbert, Ariz., satellite manufacturing operation. The companies are suing one another over the final purchase price, with Orbital arguing that the losses it expects to incur on the fixed-price LDCM contract should be factored into the equation.

General Dynamics Advanced Information Systems signed the $116 million contract for the satellite platform in 2008. As of August 2010, Orbital was projecting its losses on the program at $22.8 million, according to documents filed with the Court of Chancery for the State of Delaware. Orbital is demanding a $16.1 million refund from the $55 million it paid for the Gilbert operation. General Dynamics, meanwhile, says it is entitled to an additional $6.5 million under a price adjustment provision of the 2010 deal.

The case is expected to go to trial next year.

More recently, technical issues have arisen both on the satellite platform and on a sensor built at NASA’s Goddard Space Flight Center in Greenbelt, Md. The LDCM program consists of three main hardware elements — the satellite platform, a moderate-resolution camera built by Ball Aerospace & Technologies Corp., of Boulder, Colo., and a Goddard-built thermal infrared sensor that was added more than a year into the project.

The spacecraft suffered minor electrical damage during an April test that likely will require some replacement of components, said Ken Schwer, LDCM project manager at Goddard. NASA is still investigating the cause of the glitch, but it is not expected to affect the mission’s scheduled January launch aboard a United Launch Alliance Atlas 5 rocket, he said.

“We’re not sure yet [what failed]; that’s part of the investigation,” Schwer said in an interview here May 15. “We were removing some ground support equipment, we were installing the flight battery and after that, the team, when they were powering up the spacecraft, noticed an invalid telemetry.”

Schwer expects the investigation to conclude by the end of May. Damage, he speculated, would be limited to components such as diodes and microchips, some of which will be replaced and all of which will have to be retested.

“Over the past month, a team of NASA and Orbital engineers has conducted a series of follow-on tests to determine the root of the anomalous telemetry output,” Barron Beneski, a spokesman for Dulles, Va.-based Orbital, said in a written response to Space News queries. “NASA and Orbital have not yet determined the root cause.”

LDCM was originally supposed to have launched last July, but NASA in 2009 decided to delay the mission about a year and a half after an independent review determined it had less than a 20 percent chance of staying on schedule and within budget. LDCM is now expected to cost $931.2 million to build, launch and operate for five years, according to a Government Accountability Office estimate published in March.

The April testing glitch on LDCM occurred as NASA was working to correct a problem with the spacecraft’s Thermal Infrared Sensor (TIRS) instrument. The sensor’s cryogenic cooler lost its supply of helium due to a leak traced to the device’s fill tube. Del Jenstrom, deputy project manager for LDCM, said the leak could have occurred in late January, around the time the TIRS instrument was shipped to Arizona to be mated with the spacecraft.

Engineers closed the leak by fitting the tube with a valve assembly. The fix did not require disassembling the TIRS instrument, so only the new valve assembly was put through verification tests after the repair, Jenstrom said.

“It’s going through a purge and refill process for the next two weeks to remove any impurities in the helium that’s in the cooler,” Jenstrom said. “By the end of this month it will be fully ready for full TIRS operation and we can reinstall it back on the spacecraft in June. We’re going to launch with a fully operational TIRS instrument.”

The cryogenic cooler was purchased from Ball Aerospace, which oversaw the fix, said Roz Brown, a spokeswoman for that company.

“Testing as of last week indicated the cooler is now fully functional,” Brown wrote in a May 16 email to Space News.

The $160 million TIRS instrument was a late addition to LDCM and is designed to collect images in two thermal bands.

LDCM’s other major instrument, the Operational Land Imager, will record imagery in nine bands in the visible, near-infrared and shortwave infrared portions of the spectrum. Ball built that instrument under a 2007 contract originally valued at $127.8 million but whose cost has since risen to $188.7 million.

The nearly 50 percent cost increase on the Operational Land Imager instrument was “primarily due to contract changes to accommodate a 17 month launch date change that was instituted during mission formulation, and due to design changes made to better accommodate the TIRS instrument on the satellite,” NASA spokeswoman Rani Gran said.

LDCM is the latest in a series of medium-resolution land imaging missions the U.S. government has been launching since 1972. Recent Landsat missions have been partnerships between NASA and the U.S. Geological Survey. NASA builds and launches the spacecraft while the Geological Survey, part of the U.S. Department of Interior, maintains the Landsat data archive.

Landsat 7, currently the only functional Landsat satellite, is well past its design life — it was launched in 1999 — and has a sensor glitch that degrades the quality of its data.

Landsat 5, which launched in 1984, stopped transmitting Thematic Mapper imagery in November. A backup sensor, the Multi-Spectral Scanner, was recently activated for the first time in over a decade and is collected limited data.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.