Rotor & Wing International
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We've Come a Long Way

A look back at R&WI’s birth year of 1967 makes clear that its origin at that moment was not mere coincidence.

A look back at R&WI’s birth year of 1967 makes clear that its origin at that moment was not mere coincidence. The helicopter was at a tipping point, both technologically and operationally. The year was one of important first flights, changing commercial environments, and, above all, conflict.

The Vietnam War continued to ramp up with several thousand helicopters in theater at any given time (more than 12,000 helicopters served in Southeast Asia in a 10-year period). In 1967, manufacturers constructed unprecedented numbers of rotorcraft, and military schools turned out unprecedented numbers of helicopter pilots. During the six years the U.S. had been operating helicopters in the Vietnam theater, the helicopter had in that time moved from a niche platform for battlefield support to the centerpiece of American strategy for holding communism at bay in South Vietnam.

In the civil sector, customers began receiving the first Bell Helicopter 206 JetRangers. Although Sud-Est had ushered in the era of the commercial turbine helicopter a decade before with the Alouette II, the JetRanger marked a new phase of commercial aviation as it came to embody the minimum desired performance requirements for utility helicopters. The 206, like its other light-turbine peers of the era, was a spinoff of the military helicopter’s growing use in counter-insurgency conflicts. The U.S. Army’s Light Observation Helicopter program resulted in both the 206 and the Hughes 500, which together with the Allison T63 that powered them opened the commercial light turbine era that aided the rapid growth of the commercial helicopter industry in the 70s and 80s.

In technical terms, 1967 marked several important milestones, with military investments driving most innovations. The Mil V-12, still the largest helicopter to ever fly by a factor of two, made its first flight, while the Bell AH-1G Cobra’s use in South Vietnam marked the arrival of the purpose-built helicopter gunship. The Army had ordered the Cobra as an interim stopgap while its Advanced Aerial Fire Support System, the Lockheed AH-56 Cheyenne, came to fruition. Though it made its first flight in 1967, the rigid-rotor compound AH-56 suffered through a torturous development process until 1972, when shifts in defense priorities caused its cancellation. The Sikorsky CH-53A also had its combat debut in 1967.

The 1990s was a period of retrenchment for the helicopter industry.Photo courtesy of Roger Connor

One of the most important breakthroughs of 1967 was occurring in Europe, as the MBB Bo 105 began its tests flights. As the first commercial and military helicopter in service in both the light-twin turbine and hingeless rotor categories, it redefined helicopter performance for the next 50 years. France’s Sud Aviation 340, the prototype of the Gazelle, also had its first flight, and, like the Bo 105, proved a very capable civil/military platform. Particularly well suited to harsh operating environments, it was a crown jewel of Aérospatiale’s early line of helicopters.

Just as one promising new rotary wing industry was born in the form of the commercial light turbine market, the wheels were coming off another. The great hope of the commercial helicopter industry in the 1950s had been the spread of scheduled helicopter airlines using first-generation large turbine twins. The U.S. government had heavily subsidized three services (New York Airways, Chicago Helicopter Airways and Los Angeles Airways) initially with mail contracts and then with passenger subsidies. Its assumption was that once twin-turbine airliners like the Sikorsky S-61L and the Vertol 107 became available, the seat-mile costs would permit profitable, unsubsidized operations. The twins allowed greatly expanded operations with annual passenger loads exceeding one million by 1965, and the opening of the Pan Am Building’s rooftop heliport in midtown Manhattan was a stellar achievement, allowing a passenger to book airline passage from New York City to Disneyland without setting foot in ground transportation. Sadly the collapse of subsidies at the end of 1965 spelled eventual bankruptcy for all of the services. In 1968, a pair of disastrous crashes in Los Angeles, which killed 44, stripped the remaining luster from the American services. (Most European scheduled helicopter airline services had already collapsed by the early 1960s.)

As the Vietnam War drew to a close, reduced military contracts combined with the social and economic turmoil of the early 1970s, resulted in lean years, particularly for American manufacturers that had been in a 10-year boom. The silver lining of the times was that the flood of newly unemployed, but highly experienced pilots, a robust rotary-wing manufacturing base and the availability of very capable light turbine designs, allowed for rapid expansion as soon as favorable market conditions appeared. That would not be long.

Ancillary innovations also helped prime the industry, including lightweight television cameras that fueled the growth of TV news helicopters, while the light twins made air ambulance service into a viable business. Lighter spotlights and infrared gear (another Vietnam spinoff) made law enforcement aviation far more effective, particularly at night, when helicopters could really “shine.”

Light twin turbines like Agusta’s A109 made the air ambulance business viable.Photo courtesy of Roger Connor

Of course, what made the commercial helicopter industry truly viable were the 1973 OPEC oil embargo and 1979 energy crises. The rapid spike in oil prices fueled a massive investment in offshore energy exploration and production on both sides of the Atlantic and in the developing world. By 1975, the Gulf of Mexico was being likened to California in the Gold Rush days for helicopter pilots. The helicopter had been involved in the offshore industry since the early 1950s and energy producers had well understood its value, but compared with military production, the demand was miniscule. The 1970s changed that, though the benefits for the helicopter sector did not truly pay off until the early 1980s when new deepwater rigs proliferated through the Gulf of Mexico and the North Sea.

In the U.S., the Army’s withdrawal from Southeast Asia resulted in declining political influence coupled with shrinking budgets. Army leadership found a solution in new doctrines. “Active Defense” and “AirLand Battle” minimized the role of nuclear weapons in superpower conflict, arguing that a conventional or limited nuclear conflict with the Soviets was possible and winnable with new force-multiplying technologies in which the helicopter figured prominently. The limitations of the Huey resulted in the requirement for what became the Black Hawk. The aerial fire support program embodied by the unfortunate Cheyenne transformed from simply carrying large quantities of unguided ordinance to smaller quantities of laser-guided missiles and advanced sensors, along with powerful new engines, resulting in the selection of the Hughes AH-64 in 1976 as America’s new attack helicopter. Unfortunately for the American helicopter industry, subsystems (not airframes and rotor systems) became the dominant focus of the nation’s defense-oriented rotorcraft industry.

If the Bell 206 and Hughes 500 were hard-to-top masterpieces of design and economy in the light turbine market, the American rotorcraft industry left significant gaps for foreign and domestic competitors, both in the piston and heavy commercial turbine segments. Bell ceased production of the venerable Model 47, which had first flown in 1945, and Hiller’s UH-12 faded into the sunset in the JetRanger era. Hughes’ Model 300C enjoyed a high degree of success at this time for the training market. But Frank Robinson, who had come of age with Kaman, Bell and Hughes, saw an opportunity to create the lightest, simplest and most affordable helicopter available for the certificated market. The 1975 first flight of the Robinson R22 ushered in a resurgent helicopter training segment that helped fuel the first significant post-Vietnam generation of pilots, desperately needed by the booming offshore and aeromedical operators, like Petroleum Helicopters Inc. and Air Methods.

While in the late 1970s, American manufacturers enjoyed expanding market share with capable and affordable designs (and resurgent military investments), Westland, MBB and Aérospatiale were reaping the benefits of investments from nationalized investments in rotorcraft research and development programs. In 1961, Westland Helicopters formed from the merger of Westland’s helicopter unit, which had been largely license-building modified Sikorsky designs, and the rotary-wing sections of Bristol, Fairey and Saunders-Roe. Their military partnerships with Aérospatiale in the 1960s, created a powerful technical synergy that resulted in breakthrough aircraft like the world-record-holding Lynx. Westland’s attempt to parley its military success into a civil design, the Westland 30, highlighted the divergences between the American and European emphases in rotorcraft design. If the Westland 30 featured advanced rotor and blade designs along with an efficient transport layout, its subsystems doomed it, with underpowered engines and host of mechanical and maintenance issues in its avionics and mechanical systems.

The arrival of the Bo 105 in 1967 also demonstrated that if the previous decade had been dominated by single light turbines and the heavy twins, the next decade would mark the rise of the light twins. New engines, in the form of the Turbomeca Arriel, Lycoming LTS 101 and Pratt & Whitney Canada PW200 series helped usher in the era. The BK 117 (built by MBB and Kawasaki Heavy Industries), Agusta 109, Sikorsky S-76, Bell 222 and Aérospatiale AS360 Dauphin marked the rise of high-performance platforms that were equally at home in air ambulance, utility operations or VIP transport.

French industry reorganization spurred remarkable designs. Photo courtesy of Roger Connor

The reorganizations of the French industry that lead to Aérospatiale’s founding in 1970 proved to be a remarkable incubator for highly successful designs. The single-engine AS350 Ecureuil (AStar) and AS355 Ecureuil 2 (TwinStar) helped establish a rapidly growing European market share in North America from the late 1970s onward. However, not all of the successful twins were new designs. Improved re-engined versions of the Mil Mi-8 (Mi-8MT/Mi-17) and Bell Huey (212) became mainstays of the global heavy commercial market. In the military sector, General Electric’s T700/CT7 ushered in a new era of highly capable medium twins, ranging from the AH-64 and UH/SH-60 series during the 1970s to new NATO designs of the late 1980s and early 1990s, including the EH101 and NH90.

Besides new powerplants and hingeless rotors, the use of composites became one of the defining achievements of 1970s-era rotorcraft. Boeing was an early pioneer in the 1960s, and composites’ use rapidly proliferated in the industry during the decade.

The tiltrotor was another significant breakthrough in the era. While the 1950s and 60s had been a period of remarkable experimentation with VTOL concepts, with the exception of the Harrier, no design had proved successful enough for volume production. The partnership between Bell, NASA and the U.S. Army that yielded the XV-15 Tilt Rotor Research Aircraft built on the prior decades of work and demonstrated the increase in performance and efficiency that suggested the technology had finally neared maturity. Other high-speed rotorcraft programs, including Sikorsky’s S-69 Advancing Blade Concept helicopter not only showed promise for alternative approaches, but also that technical refinements on a broad front were necessary before the helicopter’s formula for success could be fundamentally altered.

Of the last five decades, the 1980s were the golden years of the industry. The Reagan era fueled significant military investments that realized the doctrinal shifts the Army had initiated after Vietnam. These military build-ups extended to allies and the Soviets, as Cold War tensions again increased. Combined with the petroleum industry’s boom times of the early 80s, orders surged. Manufacturers and government agencies around the world were able to invest in rotary-wing research and development like never before.

As with many momentous shifts in aviation, a disaster framed its start. The Desert One fiasco, in which a largely helicopter-borne force disastrously failed to rescue American hostages in Tehran during April 1980, gave birth to modern Special Forces aviation and formed the catalyst for the U.S. Marine Corps’ acquisition of the V-22 Osprey.

New engines in the 1970s helped usher the era of light twins like the BK 117 (bottom). Photo courtesy of Roger Connor

These boom times had their downside as well. The petroleum market crash of the mid-80s heralded a new era of market volatility for the rotary-wing industry. As helicopters became more embedded into the fabric of daily life, concerns over noise and safety rose. Popular depictions in film and television often featured villains meeting their inevitable demise in fiery helicopter crashes, lowering public confidence. As helicopter policing became more cost-effective, helicopters some times became a visible symbol of what some activists regard as an increasingly militarized form of law enforcement, reinforced by movies such as “Blue Thunder” and “Grand Canyon.” Community reactions to increased helicopter operations often centered on issues of noise and did much to ensure that if fleets were growing rapidly, heliports, particularly in suburban and urban areas, were not.

If helicopters were running into greater public resistance, they were also contributing more to society. While firefighting buckets were not new in the 1980s, SEI Industries’ collapsible Bambi Bucket, launched in 1982, made the process of aerial attack in wildfire fighting more efficient and safer. Increased utility operations came with increased peril, however. Helicopter emergency medical services, utility patrol and agricultural application operations in this period experienced an upsurge in wire-strike and controlled-flight-into-terrain accidents, with 16% of all U.S. Army aviation fatalities between 1974 and 1980 occurring from wire strikes. A partial solution emerged when Bristol Aerospace developed a Wire Strike Protection System (WSPS) for the Canadian government in 1979. Within the decade, the WSPS had proliferated through the military and was gaining acceptance for some commercial operations. Nonetheless, controlled flight into terrain remains a significant safety challenge, even as great advances in avionics have done much to improve situational awareness.

McDonnell Douglas’ NOTAR system was another 80s-era innovation that attracted considerable attention (though it has remained a niche technology), while the fenestron became a similar proprietary anti-torque hallmark for Aérospatiale. Rotor-blade design also benefitted in this golden age. The BERP (British Experimental Rotor Programme) resulted in significant payoffs in rotor performance, including lower noise profiles, creating another important avenue in rotary-wing development. Likewise, Bell’s shift from the teetering two-bladed systems to four-bladed hingeless rotor systems, beginning with the OH-58D heralded an important shift in rotor design.

Nowhere was the growing influence of the helicopter more important than the Soviet Union. While its Cold War militarism ultimately showed the limits of its power as Mi-8s and Mi-24s fell to U.S.-supplied Redeye and Stinger shoulder-fired surface-to-air missiles in Afghanistan, helicopters were essential to developing the Soviet interior. If the petroleum boom was an important economic driver in the West, it was all that stood between the Soviets and economic collapse as the debts for subsidizing the Warsaw Pact states became due. This meant exploitation of the vast resources contained in the Soviet hinterland that were entirely devoid of infrastructure. Mikhail Mil’s helicopters bridged the expanses from Siberia to the Caucuses to Sakhalin. His design bureau’s investment in heavy lift, with the Mi-26’s 40,000-lb useful load as its crowning achievement, proved that vertical lift could develop and sustain remote industrial operations devoid of terrestrial transport. The Mi-26 also gave an important gift to humanity May 12, 1986, when a heroic Mi-26 crew successfully capped the exposed reactor core at the Chernobyl power station with the lifting of a dome that weighed more than 33,000 pounds.

The Westland 30 highlighted divergences between American and European emphases in rotorcraft design.Photo courtesy of Roger Connor

If the 1980s were a boom time, the 1990s were a period of retrenchment within the helicopter industry. Military sales dropped off precipitously after the end of the Cold War, and the petroleum industry remained in the doldrums in the aftermath of the 1990 recession. The Osprey’s 28-year cycle between first flight and operational deployment is a case study in the challenges of VTOL development in the modern era, but there were also signs that rapid innovation was possible, particularly when the focus was on improving airframe and rotor fundamentals rather than subsystems. Frank Robinson’s R44 provided a platform that could provide turbine-like performance at a significantly lower operating costs, which was well suited to the boom-and-bust cycles of the era and benefitted from significant weight reductions in television and forward-looking infrared systems.

The first decade of the 21st century posed significant challenges for the rotorcraft industry. 9/11 and the War on Terror found that the post-Cold War atrophy of rotary-wing forces had consequences, and the industry struggled for half a decade to catch up to military demand. Meanwhile, a raft of Pentagon cancellations ranging from RAH-66 Comanche and VH-71 presidential transport to the ARH-70 Arapaho, along with the near-termination of the MV-22 Osprey, illustrated that the low-hanging fruit of innovation that had driven the industry in the 1960s, 70s and 80s had given way to engineering challenges that required significant investments for even moderate improvements in performance.

There were some bright spots. The Osprey survived its ordeals and proved well-suited to the operational environments of the War on Terror. In 2005, Sikorsky surprised the industry by developing its own high-speed compound helicopter demonstrator, the X2, which reached 250 kt in level flight in 2010. This program helped jumpstart interest in advancing rotorcraft performance in a way that had not been pursued since the early 1970s. Since 2000, the industry itself has continued to see further consolidation, particularly with the rise of the European Union. Airbus Helicopters and Leonardo tell the story of globalism and the transnational partnerships that have come to define the industry today, as does the Russian Federation’s consolidation of the Mil and Kamov design bureaus and their manufacturing plants under the umbrella of the Oboronprom state corporation. In the U.S., joint ventures, such as Bell and Boeing’s for the Osprey, have highlighted how difficult modern aircraft design can be for traditional corporate structures. The failure of Bell’s ARH-70 is a case study of the difficulties of pan-corporate systems integration. The recent acquisition of Sikorsky by Lockheed Martin suggests that integration along vertical lines may be a continuing trend.

Challenges still persist. The frequent hopes that the Asian market would provide explosive growth for the industry to offset the depressed petroleum market have instead revealed a slow burn. In spite of the helicopter now outnumbering fixed-wing aircraft in American military service and its central role in the War on Terror, the U.S. still does not make significant investments in rotary-wing R&D. The past seven years suggest that the industry is primed for technological disruption. If the previous five decades of rotary-wing aircraft have been the story of revolutionary improvements in subsystems (particularly engines and avionics), paired with evolutionary improvements on airframes (think of the 1950s origins of Bell’s 204 and Boeing’s 234 that will likely see close to a century of service), we now embark on a remarkable technological shift with drones impinging on traditional helicopter photography and survey roles while also posing a safety challenge. The same technologies of distributed electric propulsion and automation that made the commercial drone revolution possible now appear to also reshape vertical lift.

Whether such technologies hold the key to the financial, technical and social barriers that have kept the helicopter from being a reliable form of urban and suburban transport poses an interesting question for the next five decades, which are sure to be as exciting as the past five. RWI