#AAC25 Guardrail turns 40, modernization keeps it going

By September 30, 2014September 17th, 2018General

By Brandon Pollachek, PEO IEW&S Public Affairs

ABERDEEN PROVING GROUND, Md., July 8, 2011 — A dinner celebration on Aberdeen Proving Ground during the 2011 Special Electronic Mission Aircraft conference represented more than just an opportunity to bring together the numerous military, government and industry personnel that had been instrumental in the development and continued success of the Guardrail program, it served as an opportunity to reflect on 40 years of success with more to come.

Guardrail aircraft were first employed in Germany in 1971 to monitor Soviet Block troop movements in East Germany and Czechoslovakia, and they continued to perform that function for nearly 30 years. At the end of the Cold War three Guardrail systems were deployed to Operation Desert Shield/Desert Storm where they helped pinpoint the location of the Iraqi Republican Guard and provided over watch of other Iraqi troop movements to coalition forces — and one of the systems operated in direct support of the Marine Corps’ movement up the coast in to Kuwait City.

In addition to serving in both Operation Iraqi Freedom/New Dawn and Operation Enduring Freedom, the RC-12 aircraft continue to operate in Korea as they have done so since the mid-1970s where the aircraft help monitor the demilitarized zone.

The original Guardrail aircraft were Army U-21 aircraft modified to RU-21 configuration. Beginning in 1984, the RU-21 aircraft were replaced with upgraded RC-12 aircraft, and the last of the RU-21s were retired after the Cold War. The current inventory of Guardrail consists of 44 RC-12 aircraft made up of five different variations.

The Guardrail system

The Guardrail system recently celebrated its 40th anniversary of providing intelligence support, beginning with the Cold War through current operations in Afghanistan and Iraq. Commanders on the ground have been afforded increased situational awareness due to the missions flown by Guardrail aircraft.

Guardrail systems are supporting troops with a mix of legacy and modernized RC-12 aircraft in both Iraq and Afghanistan. Even as a major drawdown is ongoing in Iraq the system will be one of the critical capabilities that will leave last.

“They (Guardrails) will probably turn the lights out in Iraq because they are providing overwatch for the departure route into Kuwait as they continuously fly along that route listening (for enemy activity),” said Mark O’Neill, the product director for Aerial Information Surveillance and Reconnaissance systems.

From its earliest employment in the Cold War to current efforts in Iraq and Afghanistan, Guardrail has continued to provide the most timely, accurate and relevant tactical signal intelligence, or SIGINT, to tactical commanders. Although current systems look very different and have undergone multiple upgrades to deliver cutting edge technology, the philosophy behind their use has remained the same since they first came off the production line in 1971.

Intelligence gathered during Guardrail missions is sent back to analysts operating in ground stations outside hostile areas. “The reach back capability puts the pilots forward but it keeps a huge footprint out of theater. Now, it is just two pilots and all the data is remoted back,” said O’Neill.

Continued success for the Guardrail program has been achieved through progressive upgrades over the past 40 years. The program is currently going through a major modernization that, in addition to improving operational capabilities, will also alleviate sustainment and training demands.

With five RC-12X modernized Guardrails in the inventory and nine more to come, pilots, operators and maintainers will for the first time in the Guardrail history have common systems to work with as opposed to the differences the four various legacy systems that are still in the inventory offer.

Guardrail is transforming to meet the emerging demands as the platform is being modernized to add greater ability to intercept enemy activities.

“We took 1970’s technology off the receivers, increasing the throughput by a 100 times based on the upgrades in computer technology and processing speeds. Before, we might have been able to conduct 100 direction finding lines of variant in a minute now we can do 10,000,” notes O’Neill.

The RC-12X includes expanded frequency ranges, a capability to locate signals in both stand-off and stand-in modes, and an adaptive beam-forming antenna array that is capable of locating emitters in the dense signal environments. Collectively, these capabilities provide a unique tactical focus to prosecute modern networked targets encountered in the current era of persistent conflict.

The Internet-Protocol based architecture is designed for rapid integration of new capabilities — often merely by loading new software instead of requiring new special-purpose signal processors. Upgrades to the system not only represent increased capability but also a change in focus to mirror the current irregular warfare environments the aircrafts operate in.

“When Guardrail was originally designed it was designed as a stand-off Cold War asset, the airplanes were designed to look out and over into East Germany, however, in today’s fight you also want to be able to look in as close as you can,” noted O’Neill. “We have calibrated the sensors so that they can work at either range and increased the coverage area to support close in operations.”

“The RC-12X aircraft represents the current state-of-the-art in airborne SIGINT technology, and were designed to be interoperable with other Army and Joint SIGINT systems,” said Col. Mike Popovich, the Training and Doctrine Command capability manager for intelligence sensors. “The RC-12X system is designed with an open architecture that is also capable of being easily upgraded through technology insertion of hardware or software developed by other services or government agencies.”

“The Army is fielding the RC-12X systems as quickly as possible because they provide a critical capability to rapidly provide identity resolution, and their open-architecture design ensures that they are easily adaptable to remain relevant and capable of prosecuting future threats.” said Popovich. “Several of the new system have already been deployed and are providing uniquely valuable capabilities in the current operating environment.”


In celebration of the 25th anniversary of the Army Acquisition Corps (AAC), Access is publishing articles that highlight milestones throughout the history of the AAC. Each article marks a moment in acquisition excellence.

This article was published on Army.mil, July 7, 2011.