The airspace above some military bases in Hawaii is about to get busier with drone flights as the Marine Corps adds significantly to its pilotless eyes in the sky.

A dozen RQ-7B Shadows with wingspans of between 14 and 20 feet have taken up residence with support Humvees, portable antennas and other equipment in Hangar 102 at Kaneohe Bay after Marine Unmanned Aerial Vehicle Squadron 3 completed a move from California in July.

The propeller-driven Shadows, a ground-based system that needs a runway for landings, will be augmented by 45 more RQ-21A Blackjacks, an unmanned aircraft with wings 16 feet across capable of being launched and recovered from ships.

Maj. Daniel Lindblom, executive officer of the VMU-3 "Phantoms," said the Blackjacks will start arriving in fiscal 2017. Until very recently the Blackjacks were expected in fiscal 2016, but their delivery has been pushed back, he said.

The unarmed Shadow has been used in Iraq and Afghanistan to see what’s ahead without putting troops’ lives at risk, and both the 25th Infantry Division and Hawaii Army National Guard fly them in lesser numbers in Hawaii.

VMU-3, eventually expected to have 274 personnel, is the first Marine unmanned aerial vehicle squadron in Hawaii, and the Corps will be flying far more UAVs of the Shadow and Blackjack class — 57 — than any other service here.

The 25th Division said it operates about 10 Shadows, and the Hawaii Army National Guard said it has four.

Lindblom said the first training flights will take place later this month during the Lava Viper exercise at Pohakuloa Training Area on Hawaii island.

About six months from now, the Marine Corps Shadows are expected to take flight at Wheeler Army Airfield, he said. The Corps said it is still working with the Federal Aviation Administration to get approval to fly the UAVs from Kaneohe Bay, including a route that would take them out to sea.

He said no FAA approval is needed to fly the Shadows within the restricted military airspace at Pohakuloa and Wheeler.

An environmental assessment said VMU-3’s move from California to Hawaii is intended to address an aviation combat "deficiency" and ensure that Marine commanders are "supported by a balanced, geographically collocated Marine Air Ground Task Force in Hawaii."

The unit will bring to deploying Marines and sailors a degree of airborne intelligence, surveillance and reconnaissance that hadn’t been available before — short of much more expensive systems such as Predator drones or manned P-3 Orion aircraft.

"I think it’s a great opportunity for us," Lindblom said. "Everyone in this squadron is excited to be here. It’s great to be part of this Pacific shift and be in the overall realignment out here."

At up to nine hours of surveillance time for the 20-foot-wingspan Shadows, which typically fly at between 5,000 and 10,000 feet, "we can provide the on-station time that no other (Marine) aircraft can provide," Lindblom said.

Barr Group Aerospace, a consulting firm, said the Shadows cost $750,000 each in 2011.

Aerial drones, both military and civilian, have become increasingly controversial as their numbers and use have soared and civilian deaths have accompanied some military strikes.

That increased use has brought greater scrutiny from lawmakers and residents in Hawaii and elsewhere, some of whom look suspiciously upon the flying robots and worry about privacy.

Last month, a New Jersey man was arrested after he reportedly shot down a neighbor’s remote-control drone with a shotgun as the drone operator took aerial photos of his friend’s home, which was under construction, CBS News reported.

A handful of bills were introduced — but not passed — in the Hawaii Legislature this past session addressing privacy issues and drones, officials said.

Hawaii was selected in late 2013 as a test site to incorporate UAVs into the national airspace, but that effort is still pending funding from the Legislature to hire an official to run the Hawaii component.

Jim Crisafulli, director of the Hawaii Office of Aerospace Development, said UAVs are valuable for search and rescue, tracking endangered species, monitoring agriculture and other uses, but suffer an image problem from their use in military strikes in places like Afghanistan and Pakistan.

The FAA forecasts there will be 7,500 active unmanned aircraft systems in the United States in five years, with more than $89 billion invested in UAVs worldwide over the next decade.

"Unmanned aerial systems are basically out of the box," Crisafulli said. "They are here to stay. The question is, how does the government need to regulate them so they can be integrated safely into the national airspace and so that we ensure privacy?"

The Defense Department’s UAV inventory increased more than 40-fold from 2002 to 2010. The Pentagon said it had just under 11,000 aerial drones big and small in its inventory as of July 2013.

The environmental assessment for the relocation of VMU-3 said training flights will occur at Kaneohe Bay, Wheeler, Pohakuloa and the Pacific Missile Range Facility on Kauai.

The 380-pound Shadows and 135-pound Blackjacks are expected to eventually fly 480 operations annually at Kaneohe Bay, two weeks per month at Wheeler, and less regularly at Pohakuloa and the Pacific Missile Range Facility, according to the environmental assessment.

The Shadows have electro-optical daytime and infrared nighttime camera capability and have to be controlled by electronic line-of-sight, Lindblom said. They also have a laser target designator for missiles or bombs deployed by other aircraft, he said.

A 2011 Hawaii Army National Guard demonstration of the Shadow’s capabilities high over Wheeler showed that even though the UAV was practically out of sight, operators could make out people and cars fairly clearly on the ground.

VMU-3 is shipping four Shadows and trucks by barge and sending 60 Marines to Pohakuloa for training around Oct. 20 for the unit’s first flights in Hawaii, Lindblom said.

The Marines have deployed other Shadows to Pohakuloa in the past for training, the environmental assessment notes.

Per Marine Corps regulations, even while flying on the edge of restricted military airspace, the unit is not allowed to point its UAV camera outside that airspace, Lindblom said.

He said the UAVs can fly in multiples at one time for separate mission areas, but won’t be flown in formations.

Part of the reason the Marines will have so many UAVs on Oahu has to do with how they’re deployed.

The Blackjacks, which can be launched and recovered from a ship using a wire to snag the incoming UAVs wingtip, will be distributed into detachments that each have nine aircraft, Lindblom said.

Those detachments are expected to deploy on ships with the 31st Marine Expeditionary Unit out of Okinawa, Japan, and for theater security engagement and exercises, he said.

"So say Thailand wants us to go out to an exercise, or we do something in Korea. … We can send these various detachments while still rotating people in and out, and we still have the Shadows to do the same thing," Lindblom said.

The environmental assessment notes that the Marine Corps is not authorized to operate or base UAVs in Japan. As a result, the decision was made to relocate VMU-3 to Hawaii, rather than Japan.

The assessment also says that while the Shadows and Blackjacks do not have weapons capability, "if/when weapons systems are fully developed and approved for use, VMU-3 would conduct air-to-ground ordnance delivery operations at locations where munitions training is authorized for military aircraft."