NATIONAL HARBOR, Md. — The long awaited upgrade of Northrop Grumman’s MQ-8C Fire Scout unmanned helicopter with weapons remains effectively on hold as the Navy determines what munitions the littoral combat ship will carry in its armory going forward, the service’s program manager said Monday.

The Navy has a longstanding requirement to integrate the MQ-8C — an unmanned Bell 407 designed to operate from the Freedom and Independence class LCS and collect surveillance — with the advanced precision kill weapon system (APKWS), a BAE Systems product that transforms unguided 2.75-inch rockets into a precision-guided round.

However, the service will not be able to move forward with that effort until at least 2023, said Capt. Jeff Dodge, head of PMA-266.

“That development is in hiatus right now as we deal with ship integration issues and the limited magazine space that we have in trying to find out what the weapons mix should be” onboard a littoral combat ship, he told reporters at the Navy League’s Sea Air Space conference.

The Navy previously conducted land-based tests of the APKWS on an MQ-8B, an earlier version of the Fire Scout derived from the Schweizer 333. But although the tests “went great, from an airframe standpoint,” according to Dodge, future shipboard integration presents a challenge.

“One of the issues with advanced precision kill weapon system is — because its based on an unguided rocket— it’s designed to be built up in an armory, and the LCS armory doesn’t have the space to do the build up,” he said.

One potential solution is to ship each round already assembled, which would allow the weapon to fit in the LCS armory, Dodge said.

But another limiting factor is the future configuration of the LCS itself. As the Navy studies how to balance LCS survivability with the ship’s other capabilities and mission sets, service leaders are rethinking which weapons the ship should store for both itself and its onboard aircraft.

“That hasn’t resolved to give us a clear way forward that would make it a worthwhile investment at this point to continue the testing,” Dodge said.

If the Navy moves forward with weaponizing the MQ-8C, Dodge said the service will first do a quick assessment of whether APKWS is still the right fit for the Fire Scout. If so, the service will then evaluate how many rockets the drone will be able to carry.

“We had to go with three tube launchers for the MQ-8B because of its limited payload,” he said. “We think we can carry up to seven tube launcher which is more standard across DoD [with the MQ-8C].”

The MQ-8C is slated to enter service by the end of the calendar year.