A military helicopter is a helicopter that has been specifically engineered or subsequently adapted for deployment by a military force. The fundamental purpose of a military helicopter is intrinsically linked to its design or any modifications it has undergone. While the most ubiquitous application of these aircraft is airlift, transport variants are frequently reconfigured or retrofitted to undertake a broader spectrum of missions. These can range from combat search and rescue (CSAR) and medical evacuation (MEDEVAC) to serving as mobile command centers or even being heavily armed to provide close air support. Beyond these generalist roles, there exist highly specialized military helicopters meticulously crafted for distinct operational objectives. Notable examples include dedicated attack helicopters, observation platforms, and those designed for anti-submarine warfare (ASW).
Types and Roles
Military helicopters are indispensable components of contemporary sea, land, and air operations, lending a unique advantage through their vertical take-off and landing capabilities. Aircraft manufacturers typically develop airframes across various weight and size categories, which can then be tailored for diverse roles by integrating mission-specific equipment. This modular approach, often driven by the imperative to curb development expenditures, allows for the adaptation of basic airframes. This can involve stretching or shortening the fuselage, upgrading engines and avionics, or even mating existing mechanical and flight systems to entirely new fuselages to create distinct aircraft. A prime illustration of this evolutionary process is the Bell UH-1 Iroquois, affectionately known as the "Huey." This versatile platform has spawned numerous derivatives, including the Bell AH-1 attack helicopter, through modifications such as fuselage stretching and engine enhancements.
The advent of modern helicopter design has seen the increased implementation of modular systems, granting the same airframe the flexibility to be configured for different missions with relative ease. For instance, the AgustaWestland AW101 "Merlin", operated by the Royal Navy, can be rapidly reconfigured for either anti-submarine warfare (ASW) or transport duties within a matter of hours. To maintain this operational agility while simultaneously controlling costs, a strategy of fitting airframes for a system rather than with it has become prevalent. A compelling example is found within the US Army's Boeing AH-64D Apache fleet, where all variants are provisioned to accommodate the advanced Longbow radar system. However, the limited number of these sophisticated radar units means they are not installed on every aircraft. This allows for the system to be deployed on only those airframes requiring it at a given time, or to be acquired as finances permit.
Equipment
The majority of military helicopters incorporate a degree of armour to protect their occupants and critical systems. Nevertheless, the extent of this protection is invariably constrained by the aircraft's installed power, lift capacity, and the weight limitations imposed by the equipment itself on the useful payload. The most heavily armored areas typically encompass the cockpit, engines, transmission, and fuel tanks. Fuel lines, control cables, and the power conduits to the tail rotor may also be shielded with materials like Kevlar. Attack, assault, and special forces helicopters generally receive the most substantial armor plating. In transport helicopters, the crew compartment may or may not be fully armored, with a common compromise involving the provision of Kevlar-lined seats for passengers while leaving the main compartment largely unprotected.
Survivability is further augmented through meticulous engineering redundancy and strategic component placement designed for mutual protection. The Blackhawk family of helicopters, for example, is equipped with twin engines, enabling continued flight on a single engine under specific conditions. The engines are positioned apart by the transmission, such that if the aircraft is attacked from a particular flank, the engine on that side provides a degree of shielding for both the transmission and the engine on the opposite flank.
Advanced aviation electronics, commonly referred to as avionics, such as communication radios and navigation systems, are standard on most military helicopters. More specialized avionics, including electronic countermeasures and identification friend or foe (IFF) systems, are military-specific technologies that are frequently integrated into these platforms. Additional mission-specific payloads are installed either permanently or temporarily, depending on the operational requirements. These can include sophisticated optical and infrared cameras for scout helicopters, dunking sonar and search radar for anti-submarine variants, or augmented radio transceivers and computational systems for helicopters designated as airborne command posts.
While enhancements in armor, fire suppression, dynamic systems, and avionics are not always outwardly apparent, budgetary considerations have, on occasion, led some nations and military branches to employ what are essentially commercial-grade helicopters for military purposes. Reports suggest, for instance, that China has been rapidly expanding its assault helicopter regiments by utilizing the civilian version of the Russian Mil Mi-17. While these helicopters might suffice for training exercises or ceremonial duties, their deployment in an actual combat assault role, devoid of armor and electronic countermeasures, would be an act of extreme recklessness. China's apparent strategy appears to be one of eventual retrofitting with indigenous armor and electronics, thereby freeing up immediate capital to rapidly equip a sufficient number of regiments to support each of its Group Armies and foster widespread operational experience with helicopters.
Attack
Main article: Attack helicopter
A Z-10 of the People's Liberation Army Ground Aviation
Attack helicopters are specialized aircraft designed for direct engagement of enemy ground forces, primarily in anti-tank and close air support roles. The lineage of modern attack helicopters can be traced back to the Vietnam War era with the introduction of the Bell AH-1 Cobra. This aircraft established the now-iconic configuration: a tandem seating arrangement for the pilot and weapons officer within a narrow fuselage, a chin-mounted gun system, and rockets and missiles affixed to stub wings. To enhance their capability to detect and identify targets, contemporary attack helicopters are equipped with highly advanced sensor suites. These often include millimeter wave radar systems, enabling precise targeting even in adverse weather conditions.
Transport
• Main article: Transport helicopter
An Mi-26 operated by the Russian Air Force
Transport helicopters are the workhorses of military logistics, tasked with moving personnel (troops) and materiel to support a wide array of operations. While larger militaries often commission purpose-built aircraft for these duties, commercially available models are also frequently utilized. The distinct advantage offered by helicopters in these scenarios is their independence from traditional runways, enabling the delivery and retrieval of assets from virtually any location. Cargo can be transported either internally within the fuselage or externally via a slung load system, where the payload is suspended beneath the aircraft. Personnel are typically embarked and disembarked while the helicopter is on the ground. However, in environments where landing is impossible, specialized equipment such as rescue hoists or rappelling lines can be employed to transfer personnel while the aircraft hovers above.
Air assault represents a significant military strategy that relies heavily on the coordinated deployment of transport helicopters. This tactic involves assembling a specialized assault force at a designated pick-up zone, which is then ferried in successive waves to a landing zone (LZ). The objective is to rapidly deploy a substantial number of troops and equipment into the vicinity of the objective, thereby overwhelming enemy defenses. A key advantage of an air assault over an airborne (paratrooper) assault is the continuous resupply capability afforded by helicopters throughout the operation. Furthermore, these aircraft can transport personnel and equipment back to their original staging area or to a subsequent objective as mission parameters dictate.
Observation
An Aérospatiale Gazelle operated by the French Army Light Aviation
The earliest forms of aerial reconnaissance and observation aircraft were balloons, later supplemented by light fixed-wing aircraft such as the Taylorcraft L-2 and Fieseler Fi 156. As the first military helicopters emerged, their inherent maneuverability and ability to hover made them exceptionally well-suited for reconnaissance missions. Initially, observation helicopters relied solely on the visual acuity of their aircrew, often featuring expansive, well-glazed cockpits to maximize visibility. Over time, human observation has been significantly augmented by sophisticated optical sensor systems. These modern systems include low light level television and forward looking infrared cameras. Frequently, these sensors are integrated into stabilized mounts alongside multi-function lasers, capable of functioning as laser rangefinder devices and targeting designators for weapon systems.
By the very nature of its mission, the primary "weapons" of an observation helicopter are its sensor suite and communication equipment. Early observation platforms proved invaluable for directing artillery fire and airstrikes. With the advancements in sensor technology, modern observation helicopters can provide terminal guidance for anti-tank guided weapons, laser-guided bombs, and other munitions launched by different aircraft. While observation helicopters may also be equipped with combinations of guns, rocket pods, and occasionally anti-tank guided missiles or air-to-air missiles, their armament is typically less substantial than that of dedicated attack helicopters. These weapons are primarily intended for countering enemy reconnaissance assets, but they can also provide limited direct fire support.
Maritime
• See also: Maritime patrol aircraft
An AH-1 SuperCobra (left) and UH-1Y Venom (right) operated by the United States Marine Corps
Among the earliest practical applications of helicopters, following the availability of the Sikorsky R-4 and R-5 to British and American forces, was their deployment from naval cruisers and battleships. Initially, they supplemented, and eventually replaced, catapult-launched observation aircraft. Another crucial role filled by early helicopters was that of [plane guard], tasked with recovering pilots who had ditched near an aircraft carrier.
As helicopter technology advanced, leading to increased payload capacity and enhanced endurance, anti-submarine warfare (ASW) became a significant addition to their operational repertoire. Initially, helicopters functioned primarily as weapons delivery platforms, engaging submarines with air-launched torpedoes and depth charges, guided by intelligence gathered from their parent ship and other vessels. The 1960s marked a transformative era with the development of the turboshaft engine and advancements in transistor technology, profoundly reshaping maritime helicopter aviation. The turboshaft engine enabled smaller helicopters, such as the Westland Wasp, to operate from smaller vessels than their reciprocating engine predecessors. Concurrently, the integration of transistors allowed helicopters like the Sikorsky SH-3 Sea King to be equipped with integral dunking sonar, radar, and magnetic anomaly detector equipment. This culminated in aircraft capable of responding more rapidly to submarine threats to the fleet, without the need for directives from fleet vessels.
Present-day maritime helicopters, such as the Sikorsky SH-60 Seahawk and the Westland Lynx, are engineered for operation from frigates, destroyers, and similarly sized vessels. The operational requirement to carry and deploy two helicopters from frigate- and destroyer-class ships has influenced the maximum permissible size of these helicopters and the minimum size of the vessels. Continuous miniaturisation of electronics, improved engine performance, and modern weapon systems now empower even contemporary, destroyer-based, multi-role helicopters to operate with near-autonomy across ASW, anti-shipping, transport, SAR, and reconnaissance roles.
Medium and large-sized helicopters are typically operated from aircraft carriers and land bases. In the naval forces of Britain, Spain, and Italy, these larger helicopters constitute the primary anti-submarine capability within carrier air wings. When operating from shore bases, these helicopters serve as anti-submarine pickets, providing defense against hostile submarines lurking near military ports and harbors, their extended endurance and payload offering advantages over smaller counterparts.
Soviet maritime helicopters, deployed from cruisers, were also tasked with guiding the cruisers' long-range anti-shipping missiles.
Maritime helicopters are essentially navalised aircraft specifically adapted for shipboard operations. This adaptation includes enhanced protection against salt water corrosion, measures to prevent water ingestion, and provisions for safe forced ditching at sea.
Multi-mission and Rescue
A flight medic and a military dog being lifted into a rescue-equipped UH-60 Black Hawk
As helicopters entered military service, they were rapidly repurposed for search and rescue (SAR) operations and medical evacuation. During World War II, Flettner Fl 282s were utilized in Germany for [reconnaissance], while Sikorsky R-4s were employed by the United States to rescue downed aircrews and injured personnel in the remote China Burma India Theater from April 1944 until the war's conclusion. The employment of helicopters for rescue during combat operations saw a significant increase during the Korean War and the Algerian War. In the context of the Vietnam War, the USAF procured Sikorsky S-61R (known as the "Jolly Green Giant") and Sikorsky CH-53 Sea Stallion (the "Super Jolly Green Giant") helicopters specifically for the Combat search and rescue (CSAR) mission.
Training
Certain military branches utilize versions of their operational helicopters, typically lighter models, for pilot training purposes. For example, the British military has employed the Aérospatiale Gazelle in both operational roles and as a training platform. Some services also incorporate an ab initio phase in their training curriculum, which involves the use of very basic helicopters. The Mexican Navy, for instance, has acquired several commercially available Robinson R22 and R44 helicopters for this foundational training.
Utility
• Main article: Utility helicopter
A utility helicopter is a versatile aircraft designed for multiple purposes. In a military context, a utility helicopter can fulfill a range of roles, including ground attack, air assault, military logistics, medical evacuation, command and control, and troop transport.
Tactics and Operations
While not strictly essential for all combat operations, helicopters provide a substantial advantage to their operators by acting as a potent force multiplier. To maximize their effectiveness, helicopters are often integrated into a combined arms approach, working in concert with other military assets.
High Intensity Warfare
An Aérospatiale Alouette II anti-tank helicopter of the German Army armed with SS.10 missiles
High-intensity warfare is characterized by the deployment of large formations of conventional armed forces, including massed tanks, operating within environments possessing significant air defenses. The armament and tactical employment of helicopters have undergone significant evolution to adapt to these more hostile flight conditions. Advanced anti-tank missiles, such as the SS.11 and the Aérospatiale [SS.12/AS.12], were developed and integrated onto French military helicopters. In response, the United States adapted its BGM-71 TOW missile for helicopter launch and subsequently developed the [AGM-114 Hellfire]. Concurrently, the Soviet Union adapted the [3M11 Falanga] missile for deployment from the Mil Mi-24.
An OH-58 and an AH-1 of the Hawaii Air National Guard. Such a combination would have formed a hunter-killer team during the Cold War.
In aerial engagements, attack helicopters armed with anti-tank missiles often operate in conjunction with one or more unarmed or lightly armed scout helicopters. The scout helicopter, typically flying at low altitude using a nap-of-the-earth approach, endeavors to locate enemy armored columns and identify advantageous ambush positions for the attack helicopters. Later-generation scout helicopters are equipped with laser designators to guide missiles fired by the attack helicopters. Upon identifying a target, the scout can designate it, allowing the attack helicopter to fire its missile with precision before returning to a concealed position. More advanced attack helicopters, such as the Mil Mi-28N, the Kamov Ka-52, and the AH-64D Longbow, incorporate integrated sensors and command and control systems, diminishing the reliance on separate scout helicopters.
To extend the combat endurance of these missile-armed helicopters, transport helicopters are employed to ferry technicians, spare munitions, and fuel to forward operating locations. Establishing these forward arming and refueling points (FARP) at pre-determined sites and times enables armed or attack helicopters to rapidly re-arm and refuel, often with their engines running and rotors still turning, allowing for a swift return to the front lines.
Low Intensity Warfare
• Main article: Counter-insurgency
An Iraqi Armed Forces unit prepares to board a UH-60 Black Hawk for a COIN operation
In counter-insurgency (COIN) operations, government forces typically establish a presence through permanent or temporary military bases, from which patrols and convoys are launched. The objective is to deter insurgent activity and to apprehend or neutralize insurgents. However, operating from fixed bases connected by a static road network can become a vulnerability. Insurgents and their sympathizers may covertly observe these facilities, gathering intelligence on the schedules and routes of patrols and convoys. This intelligence allows insurgents to time their operations to avoid government forces or to plan ambushes, depending on their tactical advantage.
Helicopters restore a degree of surprise and tactical flexibility to the COIN commander. Patrols are no longer confined to starting and ending at the same fixed location, nor are supply convoys restricted to predictable routes. During the Rhodesian Bush War, the Rhodesian military developed and refined "Fireforce" tactics, utilizing small formations of light helicopters. These helicopters were configured as gunships for direct engagement of insurgents with aerial gunfire, and also served as airborne command/observation posts or troop transports. Once contact was made with guerilla forces, paratroopers would be deployed by a Dakota aircraft to act as "beaters," driving the guerillas towards pre-established "stop groups" landed by the helicopters.
During the Troubles, the Provisional Irish Republican Army (IRA) became adept at circumventing conventional roadblocks and patrols. To disrupt predictable patterns, patrols were deployed by helicopter, known as Eagle Patrols, which effectively hindered the IRA's ability to move personnel and arms. In the aftermath of the American invasion of Iraq, helicopters have been extensively used as aerial supply vehicles and troop transports, minimizing exposure to ambushes set by the Iraqi insurgency.
Due to the inherent cost and complexity of training and support infrastructure, insurgent forces rarely possess access to helicopters.
Manufacturers
• Main article: Helicopter manufacturers Helibras HM-1 Pantera airframes being assembled in Brazil
The principal Western European helicopter manufacturers include Leonardo S.p.A. (formerly AgustaWestland) and the Eurocopter Group. In North America, the three leading manufacturers are Boeing (encompassing its subsidiaries Boeing Vertol and McDonnell Douglas), Bell Helicopter, and Sikorsky Aircraft.
In Japan, the primary helicopter manufacturers are the aviation divisions of major Japanese conglomerates: Mitsubishi, Kawasaki, and Fuji Heavy Industries. Initially, these companies adopted a business model centered on forming strategic partnerships with foreign, predominantly American, firms. This involved the licensed production of their partners' products while simultaneously developing their own design and manufacturing capabilities through work-sharing agreements and technology transfer. In India, Hindustan Aeronautics Limited stands as the principal helicopter manufacturer for the Indian Armed Forces.
Within the Soviet planned economy system, the Mil and Kamov OKBs (design bureaus) were solely responsible for helicopter design. A subsequent reorganization of Russia's helicopter industry led to the establishment of Russian Helicopters, a holding company consolidating Mil, Kamov, and other helicopter manufacturing and maintenance facilities.
See also
Notes
• ^ Search and rescue is sometimes referred to as SAR. Search and rescue during combat is designated by NATO countries as CSAR and is a specialized personnel recovery mission.