The legacy ISR fleet of RC-12X Guardrail, MC-12S EMARSS and the EO-5C ARL-M turboprops shall be changed by the jet-powered Excessive Accuracy Detection and Exploitation System (HADES).
The U.S. Military has accomplished the divestment of its three A-ISR (Aerial-Intelligence, Surveillance and Reconnaissance) plane sorts, together with the RC-12X Guardrail, MC-12S EMARSS-M (Enhanced Medium Altitude Reconnaissance and Surveillance System-A number of Intelligence) and the EO-5C ARL-M (Airborne Reconnaissance Low-Multifunction), the service introduced on Dec. 11, 2025.
Whereas the ARL-M and Guardrail carried out their final flight missions in Korea in July, the final of the EMARSS-M plane carried out its ultimate mission in September, “bringing the fleet’s historic journey to an finish,” mentioned the press launch from the Functionality Program Govt – Intelligence, Digital Warfare and Sensors.
The retirement of those legacy plane comes because the Military’s Excessive Accuracy Detection and Exploitation System (HADES), a part of the Multi-Area Sensing System (MDSS) program, has been shaping up since 2020. 4 totally different Firm-Owned Firm-Operated (COCO) demonstrator plane, offering ISR, focusing on and ELINT/SIGINT (Digital/Alerts Intelligence) capabilities have been contracted. These will validate applied sciences, meet interim operational wants, and likewise inform the efficiency parameters for the HADES venture.
The US Military seems to be to retire its turboprop A-ISR fleet by finish of 2025, transitioning to the jet-powered HADES (ME-11B) based mostly on the World 6500. With 70 ISR turboprops in service, the shift raises issues over a looming functionality hole.
📸 Ian Harding / Bombardier pic.twitter.com/tJUPCOvnw6
— AeroResource (@AeroResource) Might 31, 2025
ARL-M, Guardrail and EMARSS
The press launch mentioned that in July the ARL-M, the Guardrail and the EMARSS marked 54 years of the Military’s A-ISR turboprop help on the Korean Peninsula, though it was not the one theatre the place they operated. The Military deployed the primary Guardrail starting 1971 to the first Navy Intelligence (MI) Battalion in Germany to watch the Soviet navy in East Germany and Czechoslovakia, sustaining this function for practically three many years.
Following the Chilly Battle, three Guardrail platforms assigned to the 224th MI Battalion and fifteenth MI Battalion have been used throughout Operation Desert Protect/Desert Storm, surveilling Iraqi Republican Guard navy actions for coalition forces, and straight supporting Marine Corps’ advance alongside the coast into Kuwait Metropolis.
Moreover, Guardrails from the third MI Battalion continued to function in Korea monitoring the demilitarized zone because the mid-Seventies. In 1996, ARL-M joined Guardrail in response to a U.S. Forces Korea and U.S. Pacific Command requirement to switch the retiring OV-1D Mohawk plane.
For the primary time ever, the ARL-M supplied a vital transferring goal indicator/artificial aperture radar (MTI/SAR) subsystem. The superior surveillance, imagery reconnaissance, goal identification, and communications intercept capabilities have been a major enchancment over the growing older OV-1D Mohawk.
The ultimate plane to affix the Military’s A-ISR turboprop fleet was the EMARSS. Based mostly upon the Beechcraft King Air 350ER platform, the primary prototype flew in 2013 and was operational by 2016, with deployments to areas together with Africa, Latin America, Iraq, and Afghanistan.
“The EMARSS program used widespread structure with 5 totally different variants permitting EMARSS plane to answer numerous operational calls for and technological developments, leading to EMARSS remaining on the technological fringe of ISR assortment,” the Military defined.
In 2006, Mission Director Sensors-Aerial Intelligence (PD SAI) led the Guardrail Modernization Program, upgrading the Military’s RC-12 fleet to the RC-12X normal, generally referred to as the Guardrail Frequent Sensor (GRCS). This changed growing older sensors and launched trendy payloads that prolonged the lifetime of the fleet by practically 20 years.
The enhancements considerably elevated the frequency vary and varieties of alerts collected, capturing and characterizing alerts inside a fraction of a second “whereas concurrently processing totally different emitters and sign sorts.”
Divestment
In 2022, the Military prioritized A-ISR funding in the direction of “deep sensing capabilities” by making sensors fly increased. “The upper the platforms fly, the additional they will acquire intelligence for a lot of sensors. The legacy turboprop fleet has restricted pace, vary, altitude, energy, and payload carrying capability […] for near-peer competitors,” the Military’s press launch defined.
The divestment of all three techniques – ARL-M, Guardrail, and EMARSS – started in fiscal yr 2023. PD SAI divested all mission tools packages (MEP) from the legacy plane, whereas the Mounted Wing Mission Workplace (FWPO) accomplished the strategic divestment of the legacy turboprop fleet in FY25. PD SAI, FWPO and the Headquarters Division of the Military (HQDA) G2 additionally staggered the divestment course of to make sure troopers nonetheless remained supported.
A number of enduring airframes have been divested, whereas some have been maintained within the present configuration for operational use. The long run HADES fleet can be a “keystone” of the “deep sensing of adversary forces and larger vary” mission.
Military’s HADES program
The Military started shaping the Multi-Area Sensing System (MDSS) Excessive Accuracy Detection and Exploitation System (HADES) program in 2020. This was supposed to switch the four-decade outdated legacy turboprop plane fleet of RC-12X Guardrail, MC-12S EMARSS and EO-5C ARL-M plane.
These can be represented by the Airborne Reconnaissance and Concentrating on Multi-Mission System (ARTEMIS), Aerial Reconnaissance and Digital Warfare System (ARES), Military Theater degree Excessive Altitude Expeditionary Subsequent Airborne ISR-Radar (ATHENA-R), and ATHENA-S (Alerts) jet platforms applications.
All of those collectively are preparatory applications and “bridging” methods that operationally deploy jet-based ISR sensing on contractor-owned and contractor-operated (COCO) plane till HADES is fielded. Additionally they assist assess “how the sensors function on the demonstrator jets on the altitudes, pace, and ranges that HADES is anticipated to carry out,” in keeping with Product Supervisor for the MDSS, Eric Hughes.
As HADES program-of-record capabilities are fielded, these bridging techniques shall be retired.
Firm-Owned Firm Operated plane
In 2023, the Military chosen L3Harris and MAG Aerospace for ATHENA-R and SNC (Sierra Nevada Company) for ATHENA-S. In Might 2025, SNC introduced efficiently finishing the preliminary Flight Efficiency Dealing with & Qualification take a look at of the Bombardier World 6500 enterprise jet within the RAPCON-X (Quickly Configurable to Any Mission-X) airframe for the ATHENA-S.
ARTEMIS has been operational since 2020, with deployments each within the Indo-Pacific and Europe. The Military valued the sooner deployment functionality of the platform, based mostly on the Challenger 650, and the flexibility to journey anyplace on the planet inside 24 hours, along with the upper efficiency in comparison with a turboprop.
ARES, additionally based mostly on the World 6500, was deployed to the Indo-Pacific in 2022. The Military mentioned that, along with a efficiency improve, ARES is nearer to the HADES venture’s long-term targets.
The ATHENA-R in the meantime had additionally deployed to South Korea in February 2025 for a four-month operational evaluation of the plane’s readiness, attainable fixes, in addition to supporting the US’ long-standing dedication to South Korea.
The ATHENA jet certainly landed at Camp Humphreys, South Korea.
This (extremely seemingly) marks the beginning of the first-ever ATHENA deployment. Of the 4 ISR bizjets, two are deliberate to be deployed in South Korea whereas the opposite two shall be deployed to the European theatre. pic.twitter.com/01wDCe7edh
— Bizjets of Battle (@bizjetsofwar) February 13, 2025
Ultimate HADES plane
The ultimate HADES prototypes, additionally RAPCON-X configured Bombardier World 6500s, would be the Military-owned large-cabin enterprise jets utilized for aerial ISR platforms. These HADES plane can have SIGINT/ELINT (Alerts/Digital Intelligence), SAR/MTI (Artificial Aperture Radar/Transferring Goal Indicator) and extra capabilities, the Military had mentioned.
We accomplished flight efficiency testing of our RAPCON-X Bombardier World 6500 jet! This Flight Efficiency Dealing with Qualification is a key milestone in proving the jet’s airworthiness with constant efficiency for the complete flight envelope. Be taught extra: pic.twitter.com/F92eu3rAd2
— Sierra Nevada Company (@SierraNevCorp) Might 8, 2025
The primary Bombardier World 6500 for the HADES mission, designated ME-11B, was delivered to FWPO in November 2024, adopted by a second in July. “The primary totally developed HADES prototype system is anticipated to be delivered in FY26 adopted by a second prototype in FY27,” the discharge additional mentioned.
The Military has nonetheless halved its future upcoming HADES fleet from 12 to 6 airframes, Breaking Protection reported in Might.
