Special mission aircraft for covert insertion

Special Operations Forces (SOF) worldwide can choose from a wide array of aircraft for covert insertion, exfiltration and resupply, with new technologies being integrated into current and developmental platforms to enhance performance and survivability.

SOF transport aircraft fall into various categories based on type, range, size and performance parameters. The vast majority are specially modified and equipped variants of general air-transport aircraft families.

Large fixed-wing aircraft

Large fixed-wing aircraft make up a significant portion of SOF transport fleets. Their advantages include very long range, high passenger or payload capacity, the ability to operate at both high and low surface ceiling, and sufficient space to integrate advanced avionics and other specialised mission systems, including optional armaments.

MC-130J

The C-130 Hercules has been used for special operations insertion for decades. The current variant operated by the US Air Force Special Operations Command (AFSOC) is the MC-130J Commando II, which entered AFSOC service in 2012; the last of the 57 ordered units will be delivered in 2025.

The MC-130J Commando II is based on the newest Hercules variant, the C-130J ’Super Hercules’. Compared to the previous MC-130H variant, the MC-130J has a 15% greater airspeed, 21% greater cruising altitude, and 25% longer range, as well as a faster climb rate, thanks in part to more efficient Rolls Royce AE 2100D3 turboprop engines with six-blade composite rotors. It is capable of landing on a 975 m dirt strip while carrying a 19,000 kg load; with a reduced payload the plane can also operate from shorter 615 m dirt strips in high mountain ranges. Onboard systems include an advanced two-pilot flight station with fully integrated digital avionics, colour multifunctional liquid crystal displays (LCDs) and head-up displays (HUDs), modern navigation systems including a dual inertial navigation system and GPS, AN/APN-241 Low Power Color Radar (LPCR), digital moving map display, Combat Systems Operator and auxiliary flight deck stations, and integrated defensive systems including the Large Aircraft Infrared Countermeasures (LAIRCM) missile detection and countermeasures system. The cockpit systems enable nighttime all-weather flight operations under blackout conditions at altitudes as low as 80 m to evade detection over hostile or non-permissive territory. The MC-130J is also equipped with the Universal Air Refueling Receptacle Slipway Installation (UARRSI) which significantly extends the aircraft’s basic 4,828 km (2,607 NM) operating range.

In addition to infiltration/exfiltration and resupply of SOF, the MC-130J also escorts SOF helicopters for long-range missions. For these Helicopter Air-to-Air Refuelling (HAAR) operations, the Hercules is equipped with underwing fuel pods. In September 2024, two MC-130J crews received awards for ’exceptional service during a high-stakes contingency operation’ involving a ten-hour nonstop flight-to-target by multiple helicopters, setting an endurance record for helicopter missions.

The MC-130J is currently being upgraded with new communications, navigation and sensors. The Block 8.X software upgrade improves satellite communications (SATCOM) security including the anti-jam NATO-interoperable SATURN UHF system. In addition, Silent Knight Terrain-Following/ Terrain Avoidance (TF/TA) radar mounted in a second radome beneath the cockpit, Radio Frequency Countermeasure (RFCM), and Airborne Mission Networking (AbMN) are all part of the planned Capability Release 2, which will enhance the aircraft’s ability to operate in high-end-threat environments. This upgraded aircraft will be redesignated ‘Combat Talon III’ to reflect the significance of its new capabilities.

A400M

The Airbus A400M Atlas turboprop is operated by seven nations, with France, Germany and the UK operating the largest fleets, making it the second most popular medium-lift aircraft worldwide after the C-130. The Atlas’ maximum speed of 741 km/h (400 kn), unrefuelled range of 6,390 km (3,450 NM) with a 20-tonne payload, and a 8,700 km (4,698 NM) ferry range, service ceiling of 12,300 m and maximum payload capacity of 37 tonnes all exceed those of the C-130J/MC-130J.

The multi-mission airframe is well-suited for SOF insertion missions, evacuation operations, and other tasks requiring covert access to contested regions. As a large airframe, the A400M can deploy SOF personnel together with a wide range of vehicles and ancillary equipment including UAVs, or a single H145M helicopter (suitable for SOF missions); alternatively, the plane’s transport bay can be configured for SOF-assisted casualty/medical evacuation (CASEVAC/MEDEVAC). Two underwing fuel pods to support long-range missions of other aircraft are available. Certification for refuelling helicopters in flight, at airspeeds as low as 194 km/h (105 kn), was approved in 2021.

The aircraft can operate from austere landing fields under total blackout conditions and have been used extensively for SOF deployments and evacuation missions in Afghanistan, the Middle East and Africa, as well as during SOF exercises in the Arctic. The aircraft is capable of very rapid descent to reduce exposure to hostile sensors or weapons. Low-level flight can conducted as far down as 90 m off the ground at airspeeds of 556 km/h (300 kn), while avoiding obstacles. Over water, the aircraft can descend to 50 m above the surface for SOF boat drop missions. Alternatively, it can deploy commandos for high-altitude (HALO/HAHO) parachute drops. French and German SOF, in particular, make extensive use of their nations’ A400Ms, and also deploy the aircraft in support of Allied special operators.

Small fixed-wing aircraft

Smaller aircraft can be preferable for missions requiring a lower profile or involving a small number of personnel, as is often the case with SOF missions. A case in point is the C-146A Wolfhound operated by AFSOC, which entered service in 2011. Measuring approximately 21.3 m in fuselage length and 21 m in wingspan, the Wolfhound is inconspicuous. Moreover, it bears no military designators or colour scheme, but a neutral blue and white which blends in with small commercial operators at major or minor airfields in any region.

The short take-off and landing (STOL) capable aircraft can conduct covert delivery of personnel and cargo, support and liaison for regional partners, and casualty evacuation missions at prepared and semi-prepared airfields. It achieves airspeeds of 500 km/h (270 kn), with an operating range of approximately 2,778 km (1,500 NM) with a payload of 907 kg (2,000 lb). The aircraft requires a three-person crew (two pilots and a loadmaster) and accommodates 27 passengers, four litter patients or 2,700 kg of cargo. The service’s 20 aircraft support overseas intra-theatre contingency operations across four geographic combatant commands. In 2023, a Wolfhound participated in Exercise Arctic Edge in northern Alaska, demonstrating it capability to operate in austere and extreme cold weather conditions.

The C-146A is based on the Dornier 328 regional airliner and modified for the military by Sierra Nevada Corporation (SNC). Modifications include: a night vision compatible cockpit; navigational aids to support operations in GPS-degraded environments; military communications systems including the ARC-231, PRC-117, and Iridium communications suite; changes to the passenger cabin to better accommodate military missions including CASEVAC; and fuselage enhancements to support STOL and austere facility operations. On 2 September 2024, Dornier and SNC celebrated 200,000 flight hours of the C-146A.

Tiltrotor aircraft

Tiltrotor aircraft combine advantages of fixed wing aircraft – such as higher airspeed, longer range and greater fuel efficiency – with the flexibility of helicopters. This makes them especially attractive to SOF.

The best known SOF-dedicated tiltrotor is the CV-22B Osprey operated by Air Force Special Operations Command (AFSOC). Primary missions include SOF long-range infiltration, exfiltration and resupply. According to the USAF, this enables the CV-22 to perform missions that normally would require both fixed-wing and rotary-wing aircraft. Initial operating capability (IOC) of the CV-22B was declared in 2009. Performance parameters include a maximum airspeed of 519 km/h (280 kn), a service ceiling of 7,600 m, and a combat radius of 926 km (500 NM) with one internal auxiliary fuel tank. In addition to the four-person crew (pilot, co-pilot and two flight engineers), the Osprey accommodates up to 24 personnel seated, 32 personnel floor-loaded or 4,500 kg of cargo. A GAU-21 12.7 mm heavy machine gun is mounted on the rear ramp.

The aircraft is equipped with a digital cockpit management system, digital map system, integrated threat countermeasures, Silent Knight TF/TA radar navigation (currently being introduced), gimballed infrared (IR) sight (typically slaved to the flight path vector), secure jam-resistant communications and other avionics optimised for the penetration mission. The planned Airborne Mission Networking (AbMN) upgrade, which is also being applied to the MC-130J, will provide the crew with a common air/ground picture and help to manage complex workloads. Other ongoing and planned upgrades include an infrared searchlight, lightweight ballistic armour, electronic warfare upgrades, and improved situational awareness tools. The engine nacelles are being modified to reduce their infrared signature and dust ingestion, and to remediate mechanical issues with the proprotor gearbox which have been identified as the cause of a deadly CV-22B accident in 2023.

To finance the ongoing upgrade programme, the USAF has placed 15 of the 51 operational CV-22B aircraft in ‘flyable storage’ status until at least 2026. Current plans do not call for net retirement of aircraft before 2029. “With respect to the CV-22 at large, it is answering a long-held requirement and that no other capability can answer in the special operations community as we go forward,” said AFSOC Commander Lt. Gen. Tony Bauernfeind in February 2024.

Helicopters

For short-to-medium range SOF insertion, helicopters remain the aircraft of choice for most nations. Their primary benefit is the flexibility to deliver and retrieve operators to and from very small landing zones in urban as well as natural terrains, including through fast-rope insertion and winch recovery.

Heavy Lift

The US Army Special Operations Command’s MH-47G Chinook is the SOF-dedicated variant of Boeing’s multi-mission heavy-lift CH-47F helicopter. Currently the largest operational SOF helicopter, the Chinook has the capacity for 33 combat-equipped soldiers (or a smaller number of personnel with tactical vehicles), plus the three-person crew. Personnel can egress and embark quickly via the stern ramp or via the Fast Rope Insertion Extraction System (FRIES). The MH-47 is armed with M134 7.62 mm gatling and M240 7.62 mm machine guns to provide suppressive fire. The AN/AAQ-24 LAIRCM countermeasure system provides defence against heat-seeking missiles.

The upgraded Block II variant of the MH-47G is currently in production, with first deliveries to the Army in 2020. The new variant has a lighter but more rigid airframe, an upgraded drive system and the Advanced Chinook Rotor Blade, which together improve lift performance and efficiency, especially at high altitude and hot conditions. New, unsegmented fuel tanks increase capacity, improving range over previous iterations. The helicopter has an unrefuelled operational range of 630 km (340 NM) and an extendable refuelling probe to enable longer-range insertions. Maximum airspeed is 315 km/h (170 kn), with a cruise speed of 222 km/h (120 kn).

The Block II’s Common Avionics Architecture System (CAAS) integrates upgraded software and hardware components, including active matrix LCDs and newer processors. FLIR and a multi-mode/terrain following radar system enable pilots to navigate through narrow canyons and gaps, flying with as little as 200 m error space on either flank while using terrain to mask their approach. The 6,100 m service ceiling makes the helicopter suited for mountain operations, with two extendable fuel dump pipes mounted at the rear of the fuselage permitting rapid weight reduction if additional lift is needed in the thin air of high altitudes.

Medium lift

Worldwide, numerous medium-lift multi-mission helicopters have been adapted for SOF operations. These include the Airbus H225M Caracal, which the manufacturer describes as the most advanced member of its Super Puma/Cougar military helicopter family. While the Caracal (previously marketed as the EC725) is used by the armed forces of 11 nations for a variety of missions, including troop transport and CASEVAC, it has been specifically selected for SOF aviation units by France and The Netherlands. This all-weather capable aircraft can operate from both land or ships, offering maximum mission flexibility. The twin Makila 2A1 turboshaft engines and five-blade main rotor provide an exceptionally low vibration level for precision flight, reduced noise level and enhanced comfort. The H225M can be refuelled in flight, extending the 1,259 km (680 NM) range by up to ten hours of flight time, enabling non-stop long-range deployment when no permissive ground refuelling options are available. Top speed rating is 324 km/h (175 kn), with a recommended cruise speed of 259 km/h (140 kn). The aircraft carries 28 combat-equipped commandos, plus the three-person crew for assault missions and insertion. Modular armour and a variety of weapons packages can be applied on a mission-by-mission basis.

Airbus is developing a dedicated special operations variant of another proven medium lift helicopter – the NH90 – under an agreement signed in 2020 with the NATO Helicopter Management Agency. The new NH90 Standard 2 will be based on the NH90 Tactical Troop Helicopter variant, but will have numerous upgraded features developed specifically for special forces. These include a Euroflir 410 gimballed optronic sight from Safran, with displays and controls for the pilots, commandos, gunners, and loadmasters. Planned future upgrades will include the Thales TopOwl helmet featuring an integrated HUD, providing tactical information and sensor data, augmented reality and tactical 3D symbols directly to the flight crew. Future integration of the wide field of view version of Safran’s Eurofl’Eye optronic pilot aid is also planned, which will enhance the pilot’s capability to fly in reduced-visibility conditions such as sand, snow or fog. The passenger cabin will receive additional ceiling-mounted anchor points for quicker fast-rope exfiltration. The helicopter provides crashworthy seating for 20 passengers, plus the three-person crew. Maximum range is 907 km (490 NM) with a fast cruise speed of 296 km/h (160 kn). The new aircraft are destined for the French Army’s SOF, with deliveries scheduled to begin in 2025.

Light helicopters

Light utility helicopters (LUH), with their reduced visual and acoustic footprint, can be the best option for insertion of small commando or reconnaissance teams. The Airbus H145M LUH SOF was chosen in 2013 by the German special operations command. The agile aircraft has proven itself on global missions including in high (up to 6,000 m) and hot operating zones. The helicopter has a length of 13.64 m, with a maximum speed of 268 km/h (145 kn), a fast cruise speed of 241 km/h (130 kn) and a maximum range of 663 km (358 NM) with standard fuel tanks.

The H145M LUH SOF features two fast-rope beams, a high-performance camera system for reconnaissance, an electronic warfare (EW) system, and weapon mounts for fire support. The helicopter can be flown by one or two pilots, with seating for up to ten passengers (nine in the Bundeswehr LUH SOF configuration) and a sling capacity of 1,600 kg. Cabin doors can be removed before take-off to facilitate fast egress upon arrival at the target; this will not impede flight performance. The 11 m rotor diameter facilitates hover and landing in urban areas, and the fenestron minimises acoustic signature, again delaying detection while approaching the target.

Future options

Research on new or improved SOF transport options is ongoing. US SOCOM would like to see high- speed VTOL aircraft that combine the flexibility of rotary aircraft with airspeeds approaching those of jet aircraft. The Defense Advanced Research Projects Agency (DARPA) is conducting the Speed and Runway INdependent Technologies (SPRINT) on behalf of and in partnership with SOCOM. Contractors have been soliciting industry to submit proposals for a proof-of-concept technology demonstrator designed for speeds of 741–833 km/h (400–450 kn) and a range of at least 315 km (170 NM). According to DARPA, two performers – Aurora Flight Sciences and Bell Textron, Inc. – have so far been awarded contracts for Phase 1B. If previous DARPA deadlines are retained, the preliminary design work for these aircraft is to be presented by spring of 2025. If the technology proves viable, it could eventually prove to be the proverbial ‘game changer’ for SOF insertion. Experience would indicate, however, that developing and validating the technology will take considerable time.

Sidney E. Dean