NATIONAL HARBOR, Md. — This year, Northrop Grumman will begin manufacturing the first E-2D Advanced Hawkeye early warning aircraft built from the ground up with an aerial refueling capability, program officials said Tuesday.

Northrop will start cutting in modifications to the production line starting with the 46th of 75 planned aircraft slated to be procured by the Navy, said Jane Bishop, the company’s vice president for airborne early warning battle management command and control.

“We’re about to lay the keel for that aircraft,” Bishop told reporters during a briefing at the Navy League’s Sea Air Space conference. “We’ll be delivering that aircraft in the fourth quarter of 2020.”

The Navy has had a longstanding requirement to make the E-2D capable of being refueled by Air Force and Navy tankers, but at the time the aircraft began production the service could not afford it, said Capt. Keith Hash, the Navy’s E-2/C-2 program manager.

“Sometimes there’s a desire to put everything in at once, and that would be wise, but unfortunately we live in a budget constrained environment and affordability has to come into play,” he said. “So this was deferred for a few years, and as we continue to build the requirements the budget will be made available to make this happen.”

The new capability could be transformational, allowing the E-2D to spend five hours on station — twice its current threshold — and increasing the aircraft’s total mission time from four to seven hours.

That pretty much doubles the time the Hawkeye can stay in the air conducting surveillance and doing the battle management command and control mission.

The upgrade will also come at a slightly higher cost. Northrop is designing and testing the modifications under a contract valued at about $250 million, Hash said. Each production aircraft should cost about $2 million more than the planes currently rolling off Northrop’s production line in St. Augustine, Fla.

Northrop and the Navy are currently negotiating a contract for retrofitting the first 45 E-2Ds, but Hash estimates that the effort should cost about $6 million per plane.

The company has already delivered three developmental test planes in 2017 with the retrofits, and two more aircraft will begin the modification process this year, Bishop said. The most important of those upgrades involves installing a refueling probe in the wing center section where the fuel tank is located, as well as some changes to flight controls.

The refuelable version of the Advanced Hawkeye flew for the first time in December 2016. Since then, it has received gas from a KC-130, KC-135, F/A-18E/F Super Hornet and — most recently, this January — a KC-10.

It’s likely that the E-2D will also be qualified to be able to be refueled by the Air Force’s future tanker, the KC-46, and the Navy’s future tanker drone, the MQ-25, Hash said.

Valerie Insinna is Defense News' air warfare reporter. She previously worked the Navy/congressional beats for Defense Daily, which followed almost three years as a staff writer for National Defense Magazine. Prior to that, she worked as an editorial assistant for the Tokyo Shimbun’s Washington bureau.

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