Infrared Search And Track Systems And The Future Of The US Fighter Force
Tyler Rogoway
Filed to: Air Combat3/26/15 3:10pm
Infrared Search And Track Systems And The Future Of The US Fighter Force
Lockheed has a new modular sensor system for combat aircraft dubbed the "Legion Pod" that aims at plugging a major hole in US air warfare capability. It provides a bolt-on Infrared Search and Track (IRST) system for optically hunting down enemy aircraft, especially stealthy ones, that our radars have trouble detecting.
Infrared Search And Track Systems And The Future Of The US Fighter Force
The Legion Pod is pitched as a plug-and-play system that can be rapidly adapted to suit different aircraft and customers needs. Presumably, different sensors could end up being carried in the 18 inch thick pod system, not just the IRST and the data-link alone that the pod was unveiled with. Still, even as an IRST alone, it and other systems like it, may be absolutely essential when it comes to retaining America's air supremacy edge in what is quickly becoming an increasingly uncertain age of air combat.
The USAF, Navy and Marines, should be funded to field the pod en masse after its capability is verified, as the Pentagon is living in denial of its aging and very prevalent 4th generation fighter force's ability to remain relevant over the battlefields of tomorrow. At the very least, we need to train our fighter forces to counter this capability as threats that are prevalent throughout the world have been fielding similar IRST systems for decades, with newer systems being much more capable than their predecessors. We can do this by supplying our aggressor squadrons with an IRST capability, and the bolt-on Legion Pod is the best answer we've yet seen to answer this problem.
Blurry Past, Sharp Future:
Infrared Search And Track Systems And The Future Of The US Fighter Force
At its most basic level, an Infrared Search and Track system is an infrared energy detection device that is usually fitted in a spherical glass enclosure on the front of a fighter aircraft. The systems scans the airspace ahead of the jet for heat signatures caused by aircraft engines and/or skin friction caused by the aircraft flying through the air. Once the system detects a target, it usually has an ability to lock that target up, or a way to facilitate the crew in slaving their fighter's radar onto the point in space where that heat signature exists in order to attempt a radar lock. Modern variations of IRSTs can search out to intermediate ranges, track multiple targets and even engage other aircraft using its telemetry data alone.
Infrared Search And Track systems were commonplace, although questionably effective, on American fighters during the 1960s and 1970s, and saw widespread use on Russian fighters from the late 1970s on. The Sukhoi Su-27 Flanker series and MiG-29 Fulcrum series of fighters have all been fielded with an IRST 'ball' just below their windscreens.
Infrared Search And Track Systems And The Future Of The US Fighter Force
The capability of the IRST systems initially fielded on these Russian fighters is also suspect, but it is fairly well known that with the last two decades pr worth of advances in imaging technology and computer processing power, the IRST seems to have finally come of age.
How To Win In A Dogfight: Stories From A Pilot Who Flew F-16s And MiGs
Lt. Col. Fred "Spanky" Clifton is one of the most experienced aggressor pilots ever,…
Read more
Today, western fighter aircraft, namely the 'Eurocanard' series, all feature advanced IRSTs. These include the SAAB Gripen with its Skyward-G IRST, the Eurofighter Typhoon with its capable PIRATE IRST, and Dassault's Rafale with its dual aperture Front Sector Optics system.
Infrared Search And Track Systems And The Future Of The US Fighter Force
Infrared Search And Track Systems And The Future Of The US Fighter Force
Often times these modern IRST systems also include laser range finding functions and the ability to display a default raw image of what the IRST has locked onto, although this function is usually only useful to the crew at intermediate ranges and below.
Infrared Search And Track Systems And The Future Of The US Fighter Force
No American fighters feature a IRST system today. Lockheed's Legion Pod is actually designed around the highly evolved Infrared Search and Track 21 (IRST21) sensor that was evolved from the F-14D Tomcat's AN/AAS-42 IRST. On the Tomcat, this sensor was mounted beside the Television Camera System (TCS), below the nose of the aircraft. A newer version of the AN/AAS-42, nicknamed "Tiger Eyes," is currently installed on the latest export models of F-15 Strike Eagles (F-15SG, F-15K), being housed inside the left-hand intake pylon that carries the aircraft's targeting pod.
Infrared Search And Track Systems And The Future Of The US Fighter Force
The Navy's F/A-18E/F Super Hornet community is also getting the latest version of this same IRST, but in its case the IRST21 sensor and processing gear is mounted in the front section of the Super Hornet's centerline external drop tank. Because that tank now costs big bucks with the IRST mounted in it, it is no longer considered expendable and will be a fixed part of the jet when it is carried. This configuration has had its detractors, but fielding an IRST anywhere on the Super Hornet, even on the tip of a drop tank, is better than nowhere. The Super Hornet's IRST is entering low rate production now and should gain initial operating capability in the fleet by about 2018.
Infrared Search And Track Systems And The Future Of The US Fighter Force
IRSTs Change The Fighter Pilot's Playbook:
Modern Infrared Search and Track systems can search, track and target an enemy aircraft while having a better ability to differentiate discreet aircraft in formations and intermediate ranges than many traditional fighter radar systems fielded today. They are also impervious to electronic warfare and jamming, a very big deal that we will discuss in a bit. Still, their biggest advantage is that they are a passive sensor, as in they work without emitting any electromagnetic energy at all.
Infrared Search And Track Systems And The Future Of The US Fighter Force
The largest source of electromagnetic energy on any combat aircraft is from its on-board radar, which serves a similar function as an IRST when it comes to air-to-air combat. Just turning a fighter jet's radar can instantly give away the location, and at the very least, the fighter's presence. Enemy aircraft, ships and anti-aircraft ground installations have passive sensors that listen for, and are able to detect and classify, aircraft's radars' unique emission fingerprints. Even an aircraft's other, less powerful emissions, such as radio communications and some constant data-link emissions, can give away their presence to an enemy's sensitive electromagnetic 'listening' equipment.
With this in mind, the world of advanced IRSTs capable of detecting fighter sized aircraft at many dozens of miles away, even head-on, brings in a whole new world of tactics to the air combat arena. Prosecuting an air-to-air engagement with radar is like having a gun battle in a huge pitch-black warehouse with only flashlights to see. If both fighters are using their radars actively to search for one another it is like both people in said warehouse frantically looking around for each other with their flashlights on.
The guy (or gal) with the most powerful flashlight and the longest range, most powerful and accurate gun usually wins. Conversely, doing so passively is like leaving your light off and waiting for the other guy to turn on their light first. The problem is, that in the past, you still had to get a firing solution on the other guy somehow, and that usually involved turning on your radar (or your spotlight) at some point in time, or getting up so close to them that you could see them visually without your spotlight at all. This would be knife-fight territory, or in the air-to-air fighter world, infrared guided missile or even gun territory. Too close for comfort. Either way, it is not an ideal situation.
Infrared Search And Track Systems And The Future Of The US Fighter Force
With an IRST equipped jet, you can bypass any passive electromagnetic detection by the bad guy (waiting for the other guy to turn on his radar or his 'spotlight') by having the ability to actively scan for an enemy's presence without emitting any electromagnetic energy at all (whether the enemy turns on their spotlight or not no longer matters as long as you are the one with an IRST, or your IRST has superior detection range). In other words, it is like ditching the spotlight and donning a pair of night vision goggles in that massive dark metaphorical warehouse.
With an IRST, there is no longer a need to wait for the other fighter to turn on their radar. While remaining electromagnetically silent, you can detect, track and engage him or her by detecting their physical infra-red signature without giving away your presence or location at all, even when it comes time to firing a shot at relatively long distances.
READ MORE
http://foxtrotalpha.jalopnik.com/infrared-search-and-track-systems-and-the-future-of-the-1691441747
