General Atomics Aeronautical Systems (GA-ASI) earlier this month conducted a 41.9-hour flight of an MQ-1C Gray Eagle Extended Range (ER) variant, demonstrating a 68 percent improvement in endurance over the current aircraft. The manufacturer plans to start delivering MQ-1C ERs to the U.S. Army next year.

GA-ASI completed the endurance flight on August 6, flying the MQ-1C ER from its El Mirage, California test facility in a representative Army mission configuration. It is developing the variant as an engineering change proposal (ECP) to the legacy Gray Eagle, which has a maximum endurance of 25 hours. The MQ-1C ER first flew on Oct. 29, 2016, and had flown more than 260 hours as of the endurance flight.

Dubbed “Predator Plus,” the ER has a higher-horsepower (180 hp), heavy-fuel engine and two-foot-longer wingspan with embedded fuel bladders supporting 56 percent more fuel capacity than its predecessor. Maximum gross takeoff weight has increased from 3,600 to 4,200 pounds, and maximum internal payload from 380 to 500 pounds. The ER adds a centerline hard point to the Gray Eagle’s four wing hard points.

With the added endurance, GA-ASI is studying enhanced applications of the Gray Eagle, which participates in manned-unmanned teaming (MUM-T) operations with the Army’s AH-64D/E Apache attack helicopter. Fitted with a radar warning receiver, the Gray Eagle could help protect the helicopters in contested environments, the manufacturer believes.

The current Grey Eagle is powered by a 160-horsepower engine that former German aeroengine company Thielert modified from a Mercedes-Benz engine block. General Atomics acquired intellectual property from Thielert when Aviation Corporation of China (AVIC) bought the German company out of bankruptcy in July 2013. GA-ASI now does the modification.

Briefing reporters on the program on August 15 at its headquarters in Poway, California, GA-ASI executives said the manufacturer has delivered 155 of the 167 Gray Eagles the Army requires, and in May received a contract to supply 39 ER models. Anticipating the approved acquisition objective (AAO) for the program will increase to 204 aircraft, GA-ASI next year plans to double its current two aircraft-per-month production rate. This year will be the last year it builds legacy MQ-1Cs.

An MQ-1C ER production aircraft will begin flight testing this month at Dugway Proving Ground, Utah, as the Army’s first test article. A follow-on operational test and evaluation 2 (FOTE2) exercise will demonstrate the MQ-1C ER’s ability to meet Army operational requirements in preparation for fielding, which is planned for August 2018, the manufacturer said.