Project on Defense Alternatives

Rotocraft for War: Descending on a Military Dilemma

by Lutz Unterseher
Project on Defense Alternatives Briefing Memo #19
May 2001

1. Magic machine

To begin with obvious qualities: helicopters make a hell of a lot of noise, mainly due to the aerodynamics of their rotor blades. So they always announce their approach -- whether to guerilla bands who seek to evade them or to reception committees who are awaiting the arrival of a heliborne dignitary. This is counterproductive in the former case, quite helpful in the latter 1.

Another obvious quality of helicopters is their fantastic mobility. Able to pluck riders from nearly any spot and deposit them to nearly any other, they provide a flexible, albeit expensive, mode of transit. This unique quality has contributed substantially to making rotocraft a V.I.P. status symbol. Their noise plays a part too, drawing attention to the comings and goings of the rich and powerful. Especially in the United States, helicopters have become both common features of every day life and signifiers of glamour and clout. Hollywood, too, has contributed to the celebrity of this machine. Cast variously as the sky-taxi of tycoons, airborne spy platform, flying escape car, and consummate fighting machine, the helicopter is a special-effects star. When scripts demand it, helicopters can even magically dispense with their noise and gain the capacity to appear unexpectedly from behind a hill or building to suddenly transform the dramatic action -- but only in the movies.

All this cultural imagery acts on us. It is mentioned here in order to dispense with it. The issue for war-fighters and defense planners is the usefulness of helicopters in real combat. To address this, we need to peel away the cultural distortions and work our way back to a true picture of operational capabilities.

2. Fundamental features

Although able to go almost anywhere, helicopters have several significant disadvantages when compared with fixed wing aircraft of the Conventional Take-Off and Landing (CTOL) type. These disadvantages mainly stem from the fact that, for helicopters, a single mechanical element -- the rotor -- provides both lift and forward thrust. By contrast, CTOL planes benefit from an ingenious and economical division of labor: propellers or turbines provide thrust; profiled fixed wings, when exposed to horizontally streaming air, provide lift.

Among the comparative disadvantages of the helicopter are its: 2

  • Limited speed: Due to the aerodynamic characteristics of rotating rotor blades (their tips approaching the sound barrier) helicopters cannot travel faster than about 350 km/h. Since operating rotocraft close to their physical limits is hazardous, most helicopters have been built to reach speeds of 250 - 300 km/h at the most.

  • Limited service ceiling: In general helicopters cannot reach altitudes much higher than 7000 - 8000 m. For fully loaded combat helicopters (especially armored ones), maximum ceilings are even lower. This does not seem to constitute a major handicap to military helicopters because they are often used in Nap-Of-the Earth (NOE) operations. Issues of survivability dictate this mode of flying due to the speed limitation of helicopters, noted above. Flying high in combat increases exposure, facilitating detection and targeting. At slow speeds such a profile would render the chances of survival rather low. In mountain warfare, especially, the limited service ceiling of helicopters can be quite frustrating. Although they can take off from terrain as high as 4000 - 5000 m, they must do so with considerably reduced loads.

  • Limited range/payload/armor protection: Compared with CTOL planes the fuel consumption of rotocraft is not very economical. This worsens the tradeoff between range and payload: if range is a high priority, it forces a strict limit on payload (including armor protection). In-flight refueling could offer a way out of this dilemma, but it would have to occur relatively often and this would entail its own particular hazards and complications. In-flight refueling of helicopters has not become common because combat helicopters are mainly used in tactical or, at most, operational roles -- which implies ranges that make in-flight refueling impractical.

  • High cost: Rotocraft are extremely expensive machines. Due to their remarkable complexity they may well cost many times more than CTOL planes of similar speed and payload -- with respect to both procurement and operations.

Noise along with speed and load limitations contribute to helicopters being relatively vulnerable machines in general; the relevance of load limits has to do with capacity for armoring these craft. Partly compensating for its high degree of vulnerability is the helicopter's relative agility -- its capacity for quickly changing direction, which among other things makes possible the aforementioned NOE operations. 3

Another set of measures intended to overcome the helicopter's characteristic vulnerability come under the rubric of "stealth". As demonstrated by the US Army's RAH-66 Comanche, a helicopter today can be given a low-signature fuselage (with internal weapons bays) and heat (infrared) suppression that is much better than in previous designs -- if one is willing and able to bear the cost (about $30 million per unit). Also, rotor systems can be designed to generate somewhat less noise. It remains to be seen in practice, however, whether it is possible to significantly reduce the radar echo of a rotor in motion. Here there are difficulties of a more fundamental sort.

3. Some scenarios

An empirical analysis of how helicopters have figured in past war scenarios and actual conflicts can provide a basis for evaluating their prospective future roles. Roughly put, the past uses of helicopters in a military context fall into three broad categories: auxiliary functions, single-arm combat use, and combined-arms combat use. 4

3.1 Auxiliary functions

Liaison: Typically this entails flying military leaders or relevant specialists from one unit or headquarters to another. In quite a few cases CTOL planes would be equally adequate for such tasks and perform them at much lower cost. However, in modern armies light CTOL planes have become a scarce commodity. Status issues may play a part in this. (Perhaps commanders find it appealing to descend rather divinely on their troops.)

Evacuation of casualties and Search And Rescue (including Combat SAR): For these missions, helicopters have proven indispensable. It is the near-ideal machine for these tasks.

Reconnaissance, target acquisition and designation: Relevant activities range from (i) a commander's rather spontaneous surveillance flight ("just to get an overview") to (ii) general reconnaissance conducted by a dedicated force element to (iii) very demanding missions carried out by special units organizationally and/or electronically linked to combat formations (of attack helicopters or artillery etc). But only portions of these activities really require the use of helicopters. Again, light CTOL planes could often substitute -- and in relatively austere armies, they do. The US Army's almost exclusive emphasis on helicopters in these roles reflects its institutional settlement with the US Air Force over turf issues. At any rate, this class of tasks has been proven to be extremely important. If carried out in an optimal manner, the benefit to combat units can hardly be over-estimated. But optimalization typically implies "networking" -- a synergetic division of labor with other, probably unmanned, recce platforms.

Transport of goods and troops from a secure base to an uncontested target area: When road transport is not an option (due to time constraints or because the land routes are impassable), helicopters often do an excellent job. This is especially true when there are no landing strips for CTOL planes in the target area. When the impassability of land routes has to do with hostile action in the territory between the "mother base" and the landing zone, helicopter gunships may need to escort utility and cargo helicopters in order to pre-empt and suppress fire from the ground.5

3.2 Single-arm combat use
In the final phase of the Second Gulf War II U.S. Army's Apache helicopters (AH-64), guided by USAF MH-53J Pave Low helicopters, served as mobile and very flexible platforms for launching high-precision Hellfire missiles at vital points of the Iraqi ground defense in Kuwait, such as air defense sensors and communication nodes. These attacks, which preceded the coalition's counter-invasion, were mainly conducted from the FLOT (Forward Line Own Troops) and involved only a limited number of rather shallow, mainly night-time penetrations of Iraqi-held territory. (Other, more complex combat helicopter operations during the Gulf War are examined below in section 3.4.)

Another interesting example of single-arm combat use is the employment of helicopter gunships by the Israeli defense forces during the second intifada in Palestinian territory. Again combat helicopters have been used as a type of flying high-precision artillery. In this case they fired missiles in an uncontested sky at hostile sniper strongholds from beyond their opponents' reach.

Such single-arm uses of combat helicopters appear to be quite effective. Its defining feature is that helicopters are used in a stand-alone manner, rather than as part of a combined-arms operation, and not in large formations. These single-arms operations do evince a reluctance to employ helicopters over enemy-held areas. Typically it is preferred to confine these precious machines to operations from behind or along the FLOT. 6 Penetrations of hostile land are limited to helicopters like the Apache that have substantial armor protection and superior night- vision equipment (which allows them to fight at night). Even in the case of using the relatively well-protected Apache over enemy-held territory, US Army doctrine dictates generous missile artillery preparation of their avenues of approach.

3.3 Combined-arms combat use
During the second half of the Vietnam War relatively compact utility helicopters were linked in operations with the first dedicated helicopter gunships. The utility helicopters (UH-1) carried troops and often also a mix of machine guns and rocket launchers for the suppression of hostile fire. The gunships, sporting very effective machine cannon and also rocket launchers, provided additional, concentrated fire support. The flying formations tended to be large, often comprising many dozens of machines.

The doctrine for the use of these formations appeared to call for a particularly swift allocation of troops and firepower to crisis spots, culminating in aggressive action by dismounted heliborne infantry, supported with suppressive fire from the machines hovering above, which also could evacuate the entire ground force quickly in case of disaster.

This approach has fundamental shortcomings, however:

  • Amassing large helicopter formations combined-arms-style involves many people and requires a long phase of preparatory planning. It also entails a major maintenance and supply effort. The quantity of machines involved multiplies the demands imposed by their complexity. The preparation requirements increase an enemy's chances of obtaining some early warning. More generally, the time required for planning and preparation increases the likelihood that conditions will change at the target site before the force can be brought to bear. The substantial support requirements also can lead to the creation of large, hence vulnerable, mother bases.
  • In actual combat the helicopters -- troopships and gunships alike -- are deprived of their principle tactical asset: agility. This is because they are tied, more or less, to slow-moving foot infantry for whom they provide essential fire support and evacuation capacity. This tethering makes the helicopters rather easy targets.

The US Army was not alone in employing this general type of formation and operational concept. The Soviet Army had a similar practice in Afghanistan, which also entailed significant risk. In Vietnam, 2,112 U.S. helicopters (of all services) were lost to enemy action. Total helicopter losses were 4,587. The Soviets deployed far fewer helicopters to Afghanistan -- estimates of the total number deployed at any one time after 1980 range from 300 to 500+. Total losses during eight years of action were quite high: probably more than 300, which suggests that the entire force may have had to be replaced! 7

3.4 Case study: combat helicopters in the Gulf War
The US Army deployed 274 Apaches to the 1990-1991 Gulf War in fifteen battalions/squadrons. According to the US General Accounting Office (GAO) these flew more than 34 attack missions and 36 armed reconnaissance missions, each involving multiple helicopters. These missions comprised less than 700 sorties - each sortie being a flight by one aircraft. (All told, coalition air forces flew 112,000 sorties during the war; of these, about 67,000 were combat-related.) Total US helicopter losses during the war were five combat-related and 18 non-combat. US fixed-wing aircraft losses were 37 combat-related and 15 non-combat.

In addition to the single-arm combat uses mentioned in section 3.1 helicopters also functioned in more complex ways during the Gulf War. These included missions in which various types of helicopters cooperated to conduct deep assaults into Iraq and operations in which helicopters cooperated with ground units to attack Iraqi formations. Several operations involved one or more battalions of attack helicopters and one involved a rotary-wing armada of 200 aircraft. And yet, despite their size and scope, these uses did not transcend the limitations suggested in previous sections. To see why, a brief review of some of these Gulf War combat helicopter operations is necessary.

Prior to the onset of the ground war Apache battalions conducted armed reconnaissance raids on Iraqi positions to reduce their resistance and clear attack and supply routes for coalition ground forces. These mostly occurred along the outer rim of the main battle area where the XVIII Airborne Corps and French forces operated. Once the ground war began in earnest large helicopter operations occurred west of Kuwait, in Iraq proper, as the US 82nd Airborne (cooperating with the French 6th Light Armored Division) and the US 101st Airborne division moved to screen the main coalition ground forces (which lay to the East) and to interdict Highway 8 to the north.

Especially impressive was the movement of the 101st Airborne. This involved 200 helicopters, 1000 vehicles (some airlifted along with artillery), and 6000 soldiers. In an operation taking 35 hours the 101st Airborne first established a forward operating base (Cobra) 100 kilometers inside Iraq and then seized positions astride Highway 8 another100 kilometers farther north. Notably, the Iraqi military presence in these areas was sparse. (A condition also true farther to the west where the 82nd Airborne and French forces operated.) The low density of enemy troops facilitated the move by the 101st Airborne and allowed its forward operating base to be linked to the rear by a relatively secure land supply route.

Later in the war attack helicopters from the 101st joined with others from the US 12th Aviation Brigade to establish a second operating base (Viper) farther east from which they could attack Iraqi forces trying to exit Basrah on their way north. Four Apache battalions -- 72 aircraft -- worked in unison to destroy almost 100 military vehicles and weapon systems within four hours. However, this pace of activity put a severe strain on supplies of ammunition and fuel. Although supply helicopters worked feverishly to bring supplies forward, the problem was not relieved until a ground convoy reached the new operating base at nightfall.

The attack helicopters of the US 24th mechanized division and those in VII Corps worked somewhat more closely with ground maneuver units. The 24th mechanized division and the divisions of VII Corps formed the inner rings of the coalition force and their Apaches engaged denser Iraqi formations. For instance, eighteen Apaches of the 11th Aviation brigade attacked the 10th Iraqi division 50 kilometers ahead of VII Corps. The assault successfully destroyed about 100 vehicles -- but the targeted Iraqi division was already exhausted when the assault came. The residual elements of the 10th and other Iraqi divisions were in the mood to flee, not fight. Many Iraqi vehicles were destroyed from 2000 meters distance as they moved in convoy.

The Apaches of the 11th Aviation brigade might have claimed even more Iraqi assets had the assault not been delayed due to the danger of fratricide. Reducing these dangers required coordination between the Apache units and the numerous friendly ground units over which they had to pass. The delay allowed some Iraqi vehicles to move into a zone that was the responsibility of coalition fixed-wing aircraft. Apaches were not allowed to operate in this zone even though the attacks by fixed-wing aircraft -- F-111s using laser bombs -- were not sufficient to stop the masses of fleeing Iraqi vehicles. As it turned out, coordination between the two air arms was insufficiently flexible to allow better integration. This is a persistent problem that was still complicating operational planning eight years later in the Kosovo war.

Closer coordination between Apaches and ground units was attempted during the US 1st Armored Division's battle with the Republican Guard Medina division -- the largest tank battle of the war. But, according to the official US Army history of the war, problems of communication between tanks and helicopters in an environment of swirling smoke and sand forced the helicopters to break off and seek deeper targets -- which is an interesting (negative) rationale for launching deep strikes.

Apache units managed to work more smoothly with other combat elements during the 24th Mechanized Division's interdiction of fleeing elements of the Hammurabi division. In this case, artillery, armor, mechanized infantry, and Apache units worked together to halt and obliterate a long column of Iraqi vehicles. Here the coalition forces employed a spatial and temporal division of labor among their various combat arms; their cooperation was simplified by having them attack at different points or times. This worked fine against an exposed linear target. Helicopter units, for their part, helped block the Iraqi column to the north and also attacked it from the east. Attacking 18 abreast, the Apaches were able to destroy 102 Iraqi vehicles.

Thus, during Desert Storm the US Army used combat helicopters in various ways, in a variety of combinations with other units, and sometimes in fairly large formations (brigade-size or larger). The US GAO has cited Army Aviation data crediting Apache units with having destroyed more than 500 armored vehicles, 120 artillery pieces, 300 wheeled vehicles, and 240 other targets. For armored vehicles and artillery this amounts to about 7 percent of the total that the coalition claimed to have destroyed. Despite this significant score, the limitations of combat helicopters were also evident in the Gulf War - and what we did not see speaks as loudly as what we did see.

While the 101st Airborne Division did execute a deep assault into Iraq at the outset of the ground war, the first two moves of this assault did not occur over densely- or actively-held enemy territory. Operating from forward bases, the 101st Airborne remained dependent on land supply routes without which it could not have sustained high-paced attack operations for long. Keeping the Apaches supplied with ammunition and fuel - they consume 2.5 gallons per minute - was a concern throughout the land war. However, the units of the 101st Airborne enjoyed a fair amount of freedom in this war to set and modulate their own pace of operation (and consumption). They were not squeezed by enemy counter-attack. And the land lines on which they depended for adequate supply are points of vulnerability that a foe might easily exploit.

When operating over or close to large Iraqi formations, helicopter units in the Gulf War generally faced sporadic and light resistance from an already depleted, disorganized, and dispirited enemy. Combat helicopter attacks usually took the form of interdicting Iraqi units that were static or moving in convoys or in hasty retreat. In this context, the flat open terrain of the theater worked to the Apaches' advantage, facilitating reconnaissance, target acquisition, and standoff attack. The Apaches seldom "mixed it up" with aggressive enemy units, nor did they often cooperate closely with friendly ground elements under conditions of intense combat.

The Gulf War did not test combat helicopter units in the way that a swirling battle of maneuver against a capable and determined foe might. Nor did it test them in the way that a war against a stealthy foe in enclosed terrain might. Operation Restore Hope in Somalia had tested helicopter units in this latter way, with unhappy results. The Kosovo war might also have imposed such a test on helicopter units - but US command authorities decided not to run the risk. 8

4. Official options

The current mainstream of doctrinal thinking about helicopter warfare in the West concentrates on the structuring and the tactical as well as operational employment of four basic types of formations. These formations can reach brigade or even division size:

4.1 Formations integrating heliborne infantry and powerful gunships
We have already introduced this type of formation and summarized the dilemmas associated with it. Transcending these dilemmas will be difficult, although there are a number of remedial proposals such as: (i) significantly improving reconnaissance by the addition of a strong element of scout helicopters to the formation or by better co-ordination with the Air Force (especially) as well as all friendly ground troops in the area of concern; (ii) enhancing the firepower of the airborne platforms; and (iii) improving armor protection and/or stealth characteristics throughout the fleet.

4.2 Attack helicopter formations linked with mechanized cavalry
Another operational concept involves the close "organic" co-operation of attack helicopter formations (including recce and utility machines for immediate support) with ground-mobile elements of mechanized cavalry. In this concept, heliborne infantry are left out. This kind of arrangement may be well suited for missions such as offensively probing a defensive array, spearheading or pursuit, mounting a cavalry screen for heavier forces, defensive area control, and the covering of retrograde (delaying) actions.

This type of employment is also very dependent on superior intelligence and a high level of co- ordination among all the relevant actors inside and outside the combined arms team. A key issue is the flexibility of the labor division between airborne and ground-mobile elements. If the helicopter forces are too tightly connected to their comrades on the ground, we would -- once again -- get a case of tactical rigidity. This is true even though the ground element -- in this case, mechanized cavalry -- has greater mobility than dismounted infantry lacking vehicles.

4.3 Bundeswehr air-mechanized concept
The third type of formation is represented by a brigade-size organization currently under development by the German Bundeswehr. It comprises a squadron of scout helicopters, two regiments of attack helicopters, and a regiment of utility helicopters. The Bundeswehr calls this structure "air-mechanized". Originally the Bundeswehr had planned for each attack regiment to have 48 Tiger Eurocopters and the support regiment to possess an equal number of NH-90 medium transport helicopters. However, budget realities may have compelled a revision in these plans. (It now appears that the Bundeswehr is unlikely to procure more than 80 Tigers total.)9

Interestingly the brigade's transport regiment does not carry dismountable troops for ground combat. The whole formation is intended to "stay up in the air". In order to be able to accomplish this, the assigned transport machines carry fuel for range extension. The other supporting functions of these machines include electronic monitoring and counter measures, NBC probing, command and control as well as evacuation of shot down or incapacitated crews. Similar ideas are being developed in some other western nations -- France for instance.

Typically such rotocraft combat forces are to be employed at the operational level, at the disposal of a corps commander. The idea of creating air-mechanized combat elements dates back to the Cold War, to the early eighties: a time when there was much talk about Soviet Operational Maneuver Groups (OMGs) and the evolving Airland-Battle doctrine of the U.S.Army. Military leaders and experts were preparing to dispense with the notion of linear battle. Imagining the future, they thought that freewheeling maneuver warfare - non-linear battles with open flanks and occasional "insular" constellations - was increasingly likely. In this context, advanced thinkers looked to employ air-mechanized formations to find open enemy flanks and to strike deep. They hoped to gain the initiative in battle by posing a threat to vital installations of the other side's command structure.

Even more so than the other types of helicopter operations we have examined, the air-mechanized approach is heavily dependent for success on superior reconnaissance and the close co-ordination of all the friendly actors involved. The challenge grows geometrically with the depth of the contemplated penetration of enemy territory. And because things in war often go wrong, preferably all the machines in the formation should have armor protection and/or stealth characteristics. But, back to reality: the German air-mechanized brigade currently under development possesses nothing of the sort. Although the attack helicopter (the Franco-German Tiger) and the transport machine (NH-90) to be procured are among the most expensive assets of their kind, they have virtually no armor protection and their stealth features are not worth the name.

4.4 Heliborne light mechanized infantry
Our final case does not appear at first glance to be a combined arms approach, but instead simply an auxiliary use of heavy load helicopters to allocate very light armor to the vicinity of crisis points. The emphasis is on vicinity. In this concept light mechanized ground elements are to be flown to areas of relative safety, but in easy reach of the zone of military action with the aim of impeding an enemy breakthrough. This approach, pioneered by the German Army, has the particular advantage of not attempting to land helicopters in the midst of dense hostile fire (typically found in the zone of direct confrontation). And since light mechanized forces are capable of quick cross-country marches, the concept also allows the commander considerable flexibility in choosing landing areas.

In the days of the Cold War the German Bundeswehr intended to send heavy lift helicopters (CH-53) each carrying two armored vehicles (the tracked Wiesel) of about 3 metric tons across friendly territory to block advancing Warsaw Pact spearheads somewhere near the FLOT.10 The Wiesels would sport either 20 mm machine cannon or TOW missile launchers. Notably, there were no plans to use these assets in bold operational maneuver schemes - deeply penetrating an opponent's territory.

Since the end of the East-West confrontation, new scenarios have emerged in which heliborne light armor might play a part -- such as efforts to relieve and defend humanitarian sanctuaries. These might require heliborne light armor to cross hostile areas. This leads to the idea of attaching scout and heavily armed escort helicopters to the transport formation. The importance of such missions may make this attachment necessary on a permanent footing and require an organic form of combined-arms integration. This is why this concept has been discussed in the combined-arms section.

5. Future foes

As mainstream military thinking imagines the employment of masses of rotocraft, combined-arms fashion, for quite demanding purposes at the operational level, we might stop a moment and ask a simple question: Are we likely to face opponents warranting such an endeavour? More specifically: can we plausibly assume that Western forces will clash in the foreseeable future with relatively strong mechanized foes and fight maneuver-style non-linear battles in which large helicopter formations might play a critical role?

Today's rogue states are not what they used to be: North Korea may expire in a couple of years, Iraq remains under tight international control, Iran is in a process of democratization, Libya seeks friendly relations with the West, and Serbia is no longer under the rule of the Miloàevi? family. Other rogue candidate countries simply lack the resources to challenge the West on the scale or in the way suggested above.

India and Pakistan are in a constellation of mutual neutralization. Finally, there is the prospect of old foes -- Russia and China -- becoming new ones. Could the former once again generate a conventional military threat of some credibility, and would the latter be able to stabilize its force modernization program long enough to produce a high-caliber military capable of very large-scale combined arms maneuver? Should we even assume that we are on a collision course with these nations? Of course, given enough time -- twenty or more years -- anything is possible, but this is hardly a good basis for wagering large amounts of scarce resources to build one particular type of narrowly-specialized combat force today.

If instead we ask what are the actual operational requirements that press on us today and that we can see rising, our attention is drawn to what the U.S. military calls "complex contingencies" and "combat operations other than war". The most likely crisis scenarios of the foreseeable future may have to do with civil wars that must be stopped or contained by the international community in order to avoid (further) bloodshed and prevent regional destabilization. Likely missions might be the creation and active defense of humanitarian sanctuaries, preventive deployments to protect a country under imminent threat, or the escort of humanitarian convoys. 11 (The escort function should be approached with caution, however; although the point would be to detect and perhaps interdict threats to a convoy, helicopter escorts might themselves become easy targets.)

If in the context of such missions - especially the creation and defense of sanctuaries - helicopters are used for operations over hostile territory, their commanders are well advised to be very cautious. In a civil war the exact positions of the contending parties are often very hard to determine. Even more than in conventional maneuver warfare there is constant change involving a multitude of actors -- and often at a finer level of resolution. That is, dispersed small unit operations usually predominate. This implies that even the highest-performance reconnaissance may not be sufficient to reliably find and map those open flanks necessary for conducting deep helicopter operations with acceptable risk. Indeed, there may not be any open flanks at all. Members of armies, militia, or armed gangs may be effectively everywhere. Even if thinly spread, they might pose a considerable threat to passing helicopters. This is due to the recent proliferation of heavy machine guns, light machine cannon (with high velocity arrow-shaped projectiles), and highly accurate shoulder-fired guided missiles. In zones characterized by instability, such weapons are becoming ubiquitous among both regular and irregular troops.

6. Lessons learned

Helicopters are expensive and vulnerable. By increasing their agility, armor protection, and stealth characteristics we can to a limited extent enhance the survivability of helicopters -- but such improvements add substantially to their cost, which is already quite high. Nonetheless, the use of helicopters in auxiliary roles or in a tactical single-arm approach (such as flying high-precision "artillery") has been quite satisfactory so far.

With regard to the operational use of massive (combined-arms) heli-formations, however, there are good reasons for skepticism. First, there are few "real and present" scenarios in which such employment schemes seem truly necessary. Second, even in situations where such schemes might play a critical part, they entail considerable risk. And this pertains to their likelihood of success. Routine operations over contested territory are -- from a standpoint of risk minimization -- only acceptable if the equipment is distinctly first rate and everything (especially recce and co-ordination) goes right. In war the latter is a dubious assumption.

Generally, helicopters should fly over hostile ground only in exceptional cases. This limits their use in certain civil-war scenarios -- where potently-armed militia and gangs could be almost everywhere.

Helicopters, like air power generally, have inspired hopes (and fears) of rapid offensive action in war. However, while demonstrating great value in some roles, this instrument has not yet proven itself to be a decisive arm. Because of its inherent limitations, there is good reason to doubt that it can -- except perhaps in limited circumstances. In Vietnam and Afghanistan, where helicopters played a leading role fighting up-front in large combined arms formations, the costs were high and the results uneven (Vietnam) or poor (Afghanistan). Combat helicopters performed more successfully in the Gulf War, but their limits were also evident: deep operations posed a severe logistical challenge and their cooperation with other elements was fraught with risk. The largest deep operations skirted areas of enemy concentration; in this case, the avenues open for safe passage were vast. Perhaps most important, they operated against an enemy who had been "prepared" by five weeks of devastating aerial bombardment. Such preparation cannot be assumed, nor can any nation but one mount it.

These conclusions call into question the fascination with the combat use of rotocraft that is shared by the U.S. Army and some of its major European allies. But the United States takes the lead; Europeans want to measure up to the Americans in order to be considered serious partners. The hitch is this: not even the United States seems able to afford the type of helicopter fleet that the army's current doctrine prescribes (although at least its investment effort is credible). As for the rest of the world: no one can come even remotely close to fielding and properly maintaining this type of force - a fact confirmed by the downward revision in Germany's plans for air-mechanized forces. Actually, their prohibitive cost gives attack helicopter forces an attraction quite apart from their track record or proven usefulness; possessing this putative capability or even appearing to posses it has political and strategic cachet.

In the US Army, helicopters came into their own during the 1960s, the Vietnam war decade, when their numbers rose from 2,500 to 9,500. Today, the hope that helicopters can play a leading maneuver role on a large scale is solidly institutionalized in the US Army's aviation branch. And that hope is sustained indirectly by the many vital and undisputed services that helicopters can and do provide. In public perceptions the combat helicopter already is at least the equal of the Abrams tank as a symbol of the Army's technological sophistication -- and the tank is losing ground. This matter of symbolism is no small thing. It figures in public support, recruitment, and the inter-service competition for dollars.

And so, in trying to understand the continuing fascination with the combat role of helicopters we end where we began: with an appreciation of the power of this machine as a political and military symbol.


1. There have been numerous attempts to render rotocraft somewhat quieter, ranging from electronic "counternoise" (for "noise cancellation") to mechanical improvements. The best solution so far appears to be the concept of flexible fiber-glass rotor blades rigidly connected to the rotorhead (as pioneered by the German Bo 105). But even this approach results in only a modest reduction of noise.

2. The US Marine Corps has attempted with their V-22 Osprey to combine the main talents of the helicopter and CTOL planes (VTOL and better speed/load characteristics). However, due to technological over-complexity, costs are high for this cross-breed (about $47 million per copy) and reliability is low. The United States presently (March 2001) seems poised to abandon or curtail this effort. At any rate, the US Army has shown no interest in the craft.

3. One of the disadvantages of such operations is, however, that persons to be transported (such as infantry) often arrive at the zone of engagement seriously "air-sick", incapable of fighting.

4. Maritime uses of rotocraft have been excluded here.

5. If the rotocraft employed are rather large and if ordinary infantry is being transported, evasive tactics may have particular limitations.

6. This approach is quite similar to the tactical doctrine of the German Bundeswehr's fleet of light anti-tank helicopters (Bo 105) during the last decade of the Cold War: Dashing up to the FLOT (to prevent Soviet breakthroughs), but never crossing it!

7. Gen. (Ret.) M.Y. Nawroz, Army of Afghanistan and L.W. Grau, "The Soviet War in Afghanistan: History and Harbinger of Future War?" (Fort Leavenworth, Kansas: Foreign Military Studies Office, 1995); M. Allen, Military Helicopter Doctrines of the Major Powers, 1945-1992: Making Decisions About Air-Land Warfare (Westport, Connecticut: Greenwood Press, 1993); A. Cordesman and A. Wagner, The Lessons of Modern War, Volume 3, The Afghan and Falklands Conflicts (Boulder: Westview Press, 1991); and, M.J. Armitage and R.A. Mason, Air Power in the Nuclear Age (Urbana: University of Illinois Press, 1983).

8. The author appreciates the assistance of Carl Conetta of the Project on Defense Alternatives in developing this analysis of helicopter operations in the Gulf. The key references for this section are: Brig. Gen. R.H. Scales, Jr., Desert Storm Study Project, Certain Victory: The US Army in the Gulf War (Washington DC: Office of the Chief of Staff US Army, 1993) pp. 198-200, 216-221, 287-314; and, T. Keaney and EA. Cohen, Gulf War Air Power Survey Summary Report, (Washington DC: Government Printing Office, 1993) pp. 111-113, 198-204.

9. R. Kammerer, "Die Luftmechanisierte Brigade," EuropÁische Sicherheit, Vol. 50, No. 3, 2001.

10. Wiesel "midget tanks" for heliborne employment were part of German Army planning since the early 1980s, but their actual production did not commence before the early 1990s.

11. Consider, for instance, the case of a country that has - democratically correct - seceded from an authoritarian union whose forces are then trying to "bring it back home".


M. Allen. Military Helicopter Doctrines of the Major Powers, 1945-1992: Making Decisions About Air-Land Warfare. Westport, Connecticut: Greenwood Press, 1993.

M.J. Armitage and R.A. Mason. Air Power in the Nuclear Age. Urbana: University of Illinois Press, 1983.

A. Cordesman and A. Wagner. The Lessons of Modern War, Volume 3, The Afghan and Falklands Conflicts. Boulder: Westview Press, 1991.

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Citation: Lutz Unterseher, Rotocraft for War: Descending on a Military Dilemma Project on Defense Alternatives Briefing Memo #16. Cambridge, MA: Commonwealth Institute, May 2001.

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