Sagetech has announced a new contract with the U.S. Navy Identification Systems Branch to estimate the development of a Mode 5 military aviation transponder.

Sagetech will estimate the cost and schedule to adapt its existing 3.5-ounce civil XP transponder to add Mode 5 encrypted IFF (identify-friend-foe) technology and make it small enough to be carried by unmanned aircraft systems (UAS) like the AAI Aerosonde aircraft, Boeing/Insitu ScanEagle, and AeroVironment Puma, which all weigh less than 50lbs.

"Our Micro-Mode 5 transponder is an order of magnitude smaller than alternatives - it's a game changer," explains Sagetech President Kelvin Scribner. "We are very excited about working with the Navy on this project and we're committed to developing a Micro-Mode 5 prototype this year."

Aviation transponders work in conjunction with air traffic control (ATC) radar systems to locate and identify aircraft, facilitating airspace management. Transponders are especially important for small UAS which are too small to be seen by ATC radar unless they have a transponder. Mode 5 transponders are a militarized version of civil transponders.

Mode 5 interrogations are used by fighter aircraft to electronically determine if an unidentified aircraft or "bogey" is friendly or enemy. The Mode 5 protocol includes encryption and secret codes that change daily. NATO forces are presently upgrading all military aircraft from Vietnam era Mode 4 to Mode 5, which employs greater sophistication.

The Iraq and Afghanistan wars saw the proliferation of small UAS, proving invaluable to battlefield commanders. Because existing military IFF transponders weigh several pounds, they could not be carried by small UAS.

Sagetech's lightweight XP series of civil transponders solved the basic problem of airspace management by making small UAS visible to ATC radar, though not providing military IFF functionality. Now that small UAS are becoming mature military systems, new requirements mandate the replacement of civil transponders with military IFF versions.