The U.S. Army’s fixed-wing aviation program is one of the great and storied traditions with deep roots in powered flight. In fact, the Army owned military aviation for the first half of the 20th century; it wasn’t until the Air Force branched off to become its own entity in 1947 that the Army wasn’t the largest military air asset.

However, its fixed-wing fleet of over three hundred aircraft is still larger than many air forces in the world, and when you include the rotary-wing fleet, the Army still maintains a massive airforce.

An important piece of this is their in-house Intelligence, Surveillance, & Reconnaissance (ISR) aircraft. The latest iteration of the King Air-based ISR platform is the RC-12X and RC-12X+Guardrail aircraft. Let’s look at the program's history, where it came from, and where it’s headed.

The History of King Airs as ISR Platforms

The most popular turboprop of all time would be an appropriate platform for low- and medium-altitude ISR work. And that is exactly what the Army used the King Air for. A lot, in fact.

U-21 Ute

You will recall from our article on the history of the C-12 that the first iteration of King Airs used by the Army was not given the C-12 moniker. Instead, they were considered utility category aircraft and were called the U-21 Ute.

Also, these were the early ‘low-tail’ King Airs, derived from the first generation of King Airs. The first aircraft of the order was delivered in 1967 as a clear attempt to phase out piston-engine powered utility aircraft. All in all, the Army received about 88 of the aircraft.

The Army spent little time with ISR variants of the Ute, with RU-21A being used in Vietnam as a radio jamming aircraft. TheRU-21 Ute lineage would serve with several models in production over the years. These were all used for either electronic countermeasures (ECM), jamming equipment, or radio reconnaissance equipment.

RC-12D through Q

As ECM and ISR technology advanced, so did airplanes. The U-21 is a fine airplane; there are still hundreds of A90, and A100 King Airs flying worldwide with an excellent track record. But the first-gen King Airs were limited. For one thing, the Ute was unpressurized. This severely limited the altitudes the RU-21could operate at. Also, it was equipped with PT6A engines rated at only 550shpper side. While these are great and far better than comparable pistons, they are limited in fuel. Limited fuel=limited loiter. ISR is all about loitering times, so the Army needed an ISR platform that could operate at higher altitudes and for longer durations.

Beechcraft answered this question for them with the Super King Air program. The original King Airs were so popular that Beech made major upgrades to the aircraft, producing an up-engined Super King Air.

In fact, the first Super King Airs to hit the Army were all the way back in 1974, just a short time after the U-21 entered service. These were completely off-the-shelf aircraft, meaning they were bone stock with nothing different from civilian versions other than a paint job. The original C-12As remained in continuous service for years, later upgraded to Charlie standards, an engine upgrade from 750shp to 850shp.

These aircraft have substantially more power than the anemic U-21s. The additional horsepower did not come with substantially higher fuel burn rates in cruise, but it did allow for provisional wingtip tanks, which provided much longer loiter durations.

This brings us to the RC-12D Guardrail.

The first Guardrail aircraft went into inventory in the early 1980s. The Delta model was given to the RC-12 because these first ones were derived from C-12Ds that were already in operation.

Many of the subsequent RC-12 models were adaptations and modifications of existing C-12 models. Since the modifications were generally interior and external antennas, there was no need or advantage to buying new production aircraft instead of modifying aircraft from the existing fleet. Besides, it makes a lot of sense from a practical point of view: the base-model Hurons are used for executive transport. You want the nicest aircraft in the fleet to be presented to the General Officer staff. Obviously, this fleet won’t always be brand new, but it makes sense to put brand-new models in the USTRANSCOM pool.

You then take the seasoned ones with plenty of airframe life left on them and modify their mission.

What Is the U.S. Army Guardrail Program?

The Guardrail program has been around for along time, 52 years to be exact. The program was originally a Cold War-era system designed to warn and discover indicators of enemy movements and actions across Europe. However, throughout the long and storied history of the program, the mission has undergone a long transformation, adapting to new threats and always adding capabilities to the platform.

According to the U.S. Army Acquisition Support Center (USAASC), the Guardrail Common Sensor (GRCS) is the current Signals Intel (SIGINT) platform. As of 2017, there were 14 aircraft in the fleet, and their job is to provide nearly real-time communications intel (COMINT) and electronics intel (ELINT).

So, Who Uses the Guardrail Aircraft?

The obvious answer is the Army. But more specifically, all of the reconnaissance fleets, whether Army, Air Force, or Navy, are considered high-demand, low-inventory assets. There are only 14 RC-12X Guardrail aircraft in the inventory, which is a paltry number compared to all of the theatres of warfare we’ve been in over the past few decades.

More specifically, it is a military intelligence asset and is operated by the 116th Military Intelligence Brigadeat Fort Gordon, Georgia.

RC-12X: What Makes it Better than the Previous Versions?

Well, that’s tough to say. It is mostly just a continued evolution of airframes that have been proving themselves for more than fifty years.

For the most part, it is incremental advances in engine technology and improvements in electronics or kits to change the overall mission of the aircraft based on perceived, experienced, or anticipated threats.

Government Procurement Operated By Greenwood Aerospace

One thing has stayed the same over the years: aircraft are sensitive machines that need quality care, parts, and components to stay at peak health. The care of your fleet is our primary concern at Government Procurement, operated by Greenwood Aerospace. Whether you are looking for parts procurement, kitting services to simplify your maintenance demands, and general supply chain management, Greenwood Aerospace is here to help you.

If you have questions on how we can best support your fleet, whether a C-12 Huron, RC-12 Guardrail or anything in between, give us a call today!