Case Study

Flight Test: GTRI-Built Threat Simulators Provide Realistic Pilot Training at Alaska Range

Published: March 12, 2012

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Protecting pilots and aircraft from ground-based threats is of highest importance to the U.S. military. To promote security aloft, pilots receive realistic in-flight training on the protective electronic warfare (EW) equipment built into U.S. aircraft.

As part of its broad-based work in electronic-warfare technology, the Georgia Tech Research Institute (GTRI) has completed development of a mobile radar air defense simulator that supports training in optimal use of EW equipment. The transportable test and evaluation system, called the XM-15S threat simulator, was recently fielded at Eielson Air Force Base near Fairbanks, Alaska. Its development was sponsored by the U.S. Pacific Air Forces (PACAF).

"The XM-15S is the newest system on the ground at Eielson," said Vince Camp, a GTRI senior research engineer. "Our role there is to provide the air-defense training assets that give the pilots a realistic threat environment."

The XM-15S is being used by Red Flag Alaska, an operation conducted by PACAF that involves in-flight training missions over the Joint Pacific Alaska Range Complex. Pilots from the U.S. military, as well as from friendly nations, travel there to test their aircraft and themselves at the range, which extends more than 300 miles from Fairbanks to the Anchorage area.

The XM-15S joins another GTRI-upgraded simulator at Eielson, the XM-11S, two of which are already deployed around the base. The tracked chassis used for the simulators provide an accurate threat signature representation in addition to providing mobility on the training range.

The GTRI-built systems's main function is to reproduce the behavior of hostile radar and missile installations. Pilots flying over the threat simulators experience a realistic hostile air defense environment that activates on-board EW equipment.

The XM-15S has the capability to both acquire and track the aircraft flying over the range, just as an enemy air defense missile system would. The system employs two radars to perform these functions – an acquisition radar that uses a rotating frequency-scanned antenna for target search functions, and a target track radar that uses a phased-array antenna providing narrow, electronically steered radar beams to lock on to a target and track it.

The XM threat simulators also offer the capacity to simulate the emanated signals of hostile missile launches. Pilots flying over the range are alerted by their EW equipment that missiles have been launched – and must take evasive action just as they would in a real combat situation.

Personnel conducting Red Flag Alaska exercises track the details of each simulated encounter.  When flying is complete, they can analyze the accumulated data and report the results to the pilots.

"At the end of each training day, they're able to tell you, 'You were shot down twice' – or that a specific type of threat had a certain number of kills in a given scenario," said Camp, who is leading GTRI team integrating the XM-15S and XM-11S at the Joint Pacific Alaska Range Complex.

GTRI's experience in building both air defense equipment and test simulation equipment goes back to the 1970s. The design that led to today's XM-15S simulator originated in the 1990s as an emitter-only system capable of simply sending out a simulated threat signal.

Over the years, the XM-15S simulator went through a series of upgrades resulting in a complete emitter-receiver processor system with track and acquisition capabilities.  GTRI's most recent work on the XM-15S, which was led by GTRI senior research engineer Duane Patterson, includes upgrades relevant to the Red Flag training operations, electronics and signal-processing improvements, as well as measures aimed at preparing the equipment for harsh Alaskan conditions.

"The entire point of this effort is to give feedback to the pilots," Camp said. "The mission is to give them realistic training experiences, so they can fly in actual hostile situations with increased confidence in their capabilities and the capabilities of their equipment."