Legion Pod To Give the Eagle New Eyes

 - August 29, 2018, 5:15 AM
The Legion Pod is seen under an F-15C during the sensor system's first Eagle flight in September 2016. (photo: Lockheed Martin)

Boeing has been awarded a contract by the U.S. Air Force to perform work associated with the installation of the Legion Pod infrared search and track (IRST) system on the Boeing F-15C Eagle. The contract runs through November 30, 2020, and could potentially be worth more than $208 million. Under the deal, the Air Force has committed to a spend of $154.6 million for Boeing to conduct engineering, manufacturing, and development work, plus production, integration, test, and deployment. A total of around 130 pods is planned to equip the fleet.

Developed by Lockheed Martin, the Legion Pod houses the ASG-34 IRST21 sensor that is also part of the F/A-18E/F Super Hornet modernization program. While the Super Hornet application has the sensor installed in a converted fuel tank, the F-15C Legion Pod is a dedicated store that also has the ability to house other sensors.

As prime contractor, source selection authority, and aircraft integrator for the F-15, Boeing selected the Legion Pod for the Eagle over Northrop Grumman's OpenPod proposal in September 2017. It has a common interface that permits it to be carried by a variety of types and a pod-to-pod datalink. Having begun trials in June 2015 under the starboard intake hardpoint of an F-16, the pod first flew under an F-15C in September 2016 at Jacksonville ANGB, Florida.

Meanwhile, the IRST21 sensor has accumulated many hours on the Super Hornet since its first flight in 2014. It is the latest in a line of infrared systems produced by Lockheed Martin Missiles & Fire Control at Orlando, Florida, that began with the AAS-42 installed in the F-14D Tomcat. The first Eagle-based IRST system was the Tiger Eyes sensor mounted in the targeting pod pylon of recent international customers such as Saudi Arabia (F-15SA), Singapore (F-15SG) and South Korea (F-15K).

Legion Pod weighs around 550 pounds and has a length of 98.5 inches. It is carried on the aircraft’s centerline pylon, from where the IRST21 sensor has a good view ahead of and below the aircraft. The sensor provides long-range acquisition and tracking of aerial targets and is being adopted primarily to provide an air-to-air capability in radar-denied environments—principally against low-observable targets. It can be used to cue the fire control radar and vice versa. It also supports advanced networking features.

In May 2017, Boeing and the U.S. Air Force demonstrated a system known as Talon HATE (the full term behind the apparent acronym has not been revealed). The podded system also has an advanced IRST sensor in its forward section but principally features a complex data-fusion system that allows the aircraft to operate as a battlefield data communications network node and to interface with the F-22 Raptor.

An F-15C from the U.S. Air Force's operational test and evaluation unit carries a Talon HATE battlefield communications/IRST pod. (photo: U.S. Air Force)