Secret Army Sensor Plane Is Crucial To Situational Awareness Of Future Force

Chances are you’ve never heard of the Army’s EO-5C Airborne Reconnaissance Low planes. Chances are even slimmer you’ve actually seen one. You can find pictures of crew trainers on the internet, but the Army has decided that the sensors on the operational airframe give away too much information about the plane, so finding an accurate image is nearly impossible without a security clearance. I know, because I spent a long time looking while preparing a report on the mysterious Airborne Reconnaissance Low fleet.

ARL, as it is known among Army insiders, is probably the most densely-packed sensor plane in the world. A four-engine turboprop originally designed for use by regional airlines flying in and out of airports with short runways, the airframe was adapted to counter-insurgency and drug-war missions in the 1990s. It was so successful in finding elusive adversaries that the Army kept improving it for use in Korea, the Middle East, Africa and elsewhere. Among other things, it can generate high-rez images of enemies in visible and infrared light; fix the location of hostile radio-frequency emitters; and track moving targets using synthetic-aperture radar.

No doubt about it, being able to pierce the fog of war in darkness and dust, rain or shine, gives America’s soldiers a valuable warfighting edge. But ARL planes are so stuffed with equipment that they can’t stay aloft over targets for the preferred length of time, and maintenance has become an expensive proposition since the planes have been out of production for some time. As part of its plan to shrink and consolidate the airborne recon fleet in the aftermath of Afghanistan, the Army wants to buy new ARL planes with more endurance and less carrying costs. The need to modernize is not in question; what’s at issue is how that can be accomplished most effectively.

As far as the airframe is concerned, that’s a no-brainer. The Army needs a bigger plane in the same high-wing configuration so sensors have unobstructed visibility. The obvious candidate is Bombardier’s Q400 version of the Dash-8, essentially an evolved version of the existing ARL airframe that has two more powerful engines and is still in production. Buying an aircraft with two engines (rather than four) and a warm production base will greatly reduce maintenance costs. It will also improve the safety of occupants, since the Q400 is a more reliable product. The Q400 will deliver all the range and payload capacity the Army needs to keep ARL relevant through mid-century.

Design of a new on-board sensor architecture is a bit trickier. One reason the current plane can’t stay on station above targets as long as the Army wants is that it carries every sensor users will ever need on each mission — even when the sensors aren’t required for the mission at hand. Buying a bigger airframe will certainly help reduce the operational consequences of that practice, but a further solution would be to develop a modular, “plug-and play” architecture that allows various sensor combinations to be easily switched out as mission requirements dictate. That way, users will only have to carry the electronic “baggage” they actually need for the trip at hand. Hopefully, that’s the direction in which Army planners are headed as they begin modernization of this uniquely versatile airframe.