HUNTSVILLE, Alabama (Reuters) - The Pentagon's No. 1 arms supplier Lockheed Martin Corp (>> Lockheed Martin Corporation) sees significant growth potential for its range of unmanned aircraft, given continued military demand for surveillance aircraft and a huge untapped market in the commercial sector.

Lockheed, known for its F-16 and F-35 fighter jets and Aegis missile defense system, lacks a drone with a widely recognizable name - like General Atomics's Predator - but its portfolio includes a number of planes designed for everything from reconnaissance to bringing supplies to troops in combat.

The company is still tight-lipped about the RQ-170 intelligence drone, developed by the company's Skunkworks research division, that grabbed the limelight when one went down in Iran in 2011.

But it is more open about the prospects of a number of other unmanned aircraft and ground control stations given the Pentagon's continued need for surveillance and intelligence-gathering systems, as well as the expected opening up next year of U.S. airspace for civilian-use drones.

"There's still significant growth potential in the UAS (unmanned aerial systems) space," Steve Adlich, business development manager for Lockheed Martin Unmanned Integrated Systems, told Reuters this week in an interview.

Lockheed's unmanned aircraft range from a 5-pound Indago surveillance bird to the 12,000-pound K-MAX cargo helicopter built with Kaman Aerospace Corp (>> Kaman Corporation), that can carry 6,000 pounds in a sling.

Lockheed also makes tethered blimps, or aerostats, that have been in use since 2004 and provide security for U.S. forces in Afghanistan.

The company is particularly upbeat about the prospect of U.S. and foreign orders for Fury, a 400-pound rail-launched drone that has a range of 1,500 miles and can stay aloft for 15 hours. The drone was designed by Chandler/May Inc, a small firm acquired by Lockheed in late 2012.

Fury, which has not yet been used in combat, was developed with some government funds and is now competing for production orders, Adlich said. He declined to estimate how much of its own funds Lockheed had spent on the aircraft to date.

Adlich, who spoke to Reuters at the company's Huntsville, Alabama facility, joined Lockheed as a result of the Chandler/May acquisition.

"Long term across Lockheed corporate, we're looking at product syngergies across the whole portfolio of UAS and trying to identify areas were we can provide commonality and efficiency."

Lockheed anticipates sales of drones for commercial use, a potentially lucrative market that could take off once the U.S. Federal Aviation Administration opens up U.S. airspace to flights by unmanned aircraft by the end of 2015, Adlich said.

The manned version of K-MAX is already used for logging and firefighting, both jobs that could be done by unmanned versions of the plane, Jim Naylor, business development director for Lockheed's aviation systems business, told reporters at a conference hosted by the Association of the U.S. Army.

Karl Kettner, Lockheed's program manager for the aerostat or Persistent Threat Detection System (PTDS), said he was optimistic that the U.S. Department of Homeland Security and other civil agencies could buy some of the company's large unmanned surveillance aircraft.

Lockheed is also in talks to sell the planes to countries in the Middle East, Europe and Asia, Kettner told Reuters in a telephone interview.

Blimps and hot air balloons have been used for surveillance or reconnaissance for over 150 years, and new potential uses continue to crop up, he said.

"These systems are going to be with us for a long time to come."

(Editing by Christopher Cushing)

By Andrea Shalal

Stocks treated in this article : Lockheed Martin Corporation, Kaman Corporation