The Helicopter as a Lifesaving Tool
Sikorsky explains how today’s helicopter technology was birthed from a history of vital needs.
When one is asked to reflect on what has happened during the past 50 years since the birth of Rotor & Wing in 1967, it seems logical to go back to that year. It was a fascinating trip through time. It was a most interesting year.
In June 1967, Igor Sikorsky (my father) attended the famed Paris Air Show at the historic Le Bourget airfield. It was the 40th anniversary of Charles Lindbergh’s epic flight from New York to Paris.
He proudly watched as two U.S. Air Force HH-3s, variants of the Sikorsky S-61, landed on the airfield. The helicopters had just accomplished something that been considered impossible a few years earlier. These two helicopters had just flown, nonstop, from New York to Paris, some 4,271 miles, in 30 hours and 46 minutes. They refueled several times from Lockheed C-130 tanker aircraft.
The flight was possible because of the vision of Air Force Maj. Harry Dunn. Two years earlier, he hit on the idea of in-flight refueling HH-3 “Jolly Green Giant” rescue helicopters. Despite much skepticism, he developed the concept in time to prove it with several helicopter rescues as the air war intensified in Vietnam. By the time hostilities were over, the Jolly Greens had logged 1,490 rescues, many over distances that would have been impossible without the use of in-flight refueling.
The Vietnam War was considered by many to be a “helicopter war.” By 1967, the helicopter was changing the way the U.S. Army would fight future wars. The Bell Helicopter “Huey,” the Boeing-Vertol Chinook and the Sikorsky S-64 Sky Crane were transporting troops and supplies, repositioning heavy artillery pieces, bringing in ammunition — in short, doing everything that man, horse and mule had been doing for the previous 2,000 years, but in minutes instead of days. Although he abhorred war, Sikorsky found comfort in the growing use of the helicopter as the fastest way to evacuate wounded soldiers from the battlefield to the medical station or field hospital.
As the U.S. space program accelerated in the late 1960s, he was proud that Sikorsky helicopters were being used in a number of supporting roles. In July 1969, he watched, fascinated, the televised image of Neil Armstrong stepping off the ladder of Apollo 11 onto the moon. A few days later, he watched the “splash down” of Apollo 11 and the subsequent transport of the astronauts by Sikorsky helicopter to a waiting aircraft carrier.
Interestingly, the year 1969 not only marked mankind’s first steps on the moon, but the first flight of the Boeing 747 prototype and the French and British Concord prototypes.
In 1971, after several years of study, the Army published a document describing in detail the characteristics of a new helicopter. The requirements spelled out a next-generation utility helicopter with dramatic improvements in performance and combat survivability. In August 1972, Boeing-Vertol and Sikorsky were each awarded a contract to build two ground-test and three flight-test vehicles for a competitive evaluation. The winner of the evaluation would eventually evolve into the Black Hawk family.
In October 1972, a 30-story office building caught fire in Sao Paulo, Brazil. The flames forced 450 people upward, trapping them on the building’s roof. A handful of police and private helicopters responded. In an amazing display of courage and airmanship, the helicopters each picked up a handful of people, brought them down to a nearby area, then flew back up to pick up another group — saving all 450.
I always believed that the helicopter would be an outstanding vehicle for the greatest variety of lifesaving missions, and now, near the close of my life, I have the satisfaction of knowing that this proved to be true. — Igor Sikorsky
Jerry Lederer, founder of the Flight Safety Foundation, sent photographs and press clippings of the event to his friend, Sikorsky. In a letter dated Oct. 25, 1972, Sikorsky thanked Lederer for the information, and wrote: “I always believed that the helicopter would be an outstanding vehicle for the greatest variety of lifesaving missions, and now, near the close of my life, I have the satisfaction of knowing that this proved to be true.”
That same night, he passed away peacefully in his sleep.
On Oct. 17, 1974, the prototype Black Hawk lifted off the ground. After two years of intensive test and evaluation, first by Sikorsky test pilots, then by Army test pilots, the Sikorsky entry was chosen Dec. 23, 1976. Since then, 4,000 units have been produced, and production continues apace. It has evolved into a variety of configurations for land-based and maritime missions. Currently operated by 26 countries, the Black Hawk fleet has logged an amazing 10 million flight hours, 2 million of which are combat flight hours. Clearly, the Black Hawk family has the potential to be around for some time to come.
The Sikorsky legacy of intuitive engineering also resulted in the creation of a new, high-speed helicopter configuration. It combined a rigid-rotor coaxial configuration with jet engines. The first experimental version, the S-69, started flight-testing in mid-1973 as a pure helicopter. After extensive testing by the Army, two turbojets were added in 1977. With the additional thrust of the turbojets, the S-69 reached speeds of 322 mph. The test program ended, the engineers went back to their drawing boards, but the idea stayed alive.
That same year marked the first flights of the S-76. Aimed at the offshore oil industry, as well as executive transport, over 850 S-76s have been delivered worldwide. The S-76 carries up to 12 passengers in the offshore configuration and four to six people in the executive version. Sikorsky’s next offering was the S-92, a large transport helicopter carrying up to 19 passengers, which first flew in the year 2000. To date, more than 275 machines are in service worldwide, mostly for offshore, and search and rescue configurations.
During all this activity, the rigid-rotor coaxial S-69 was not forgotten. In 2005, Sikorsky launched a new program — the X2 technology demonstrator. Its first flight occurred in August 2008. This time, a pusher prop had been added to the rigid-rotor coaxial configuration. The X2 explored fly-by-wire technology, computer-aided flight control systems, variable power-sharing between the rotors and the pusher propeller, and a number of other possible ideas. It was a small single-pilot machine weighing about 5,500 lbs.
Then on Sept. 15, 2010, Sikorsky’s chief test pilot, Kevin Bredenbeck, flew the X2, hitting 250 kt in level flight. The demonstrator earned Sikorsky the 2010 Collier Trophy.
The X2 led to the next step in this new configuration, the S-97 Raider. The prototype Raider first flew May 22, 2015. It is twice the size and twice the weight of the X2. It will carry a two-man crew and six troops, or the equivalent weight in weapons or cargo. The S-97 Raider is currently in the test and development phase.
After many years of study, the Marines generated a requirement for a super heavy-lift helicopter to replace the venerable CH-53E. The challenge was to design a new one with virtually three times the load-carrying capability of the CH-53E, but of a size no larger than the older machine. This was dictated by the size of the elevators on aircraft and helicopter carrier ships.
The resulting helicopter, the CH-53K, looks like its ancestor, but is an entirely new development. It first flew Oct. 27, 2015. There are currently four prototypes flying in the test program. The list of new technologies for this helicopter is lengthy. However, it is interesting to note that the single main-rotor/tail-rotor configuration perfected by Sikorsky with the VS-300 (1,100 lbs; 90 hp) still seems to work with the CH-53K (88,000 lbs gross weight; 22,500 shp.)
Today, about 50 years after Sikorsky was interviewed by Rotor & Wing, the magazine continues to report on the steady growth of helicopter technology.
Fifty years ago, it would have been difficult to predict such technical advances as handheld GPS, automatic landings in zero-zero conditions and 250-kt cruise speeds for helicopters. It is equally difficult to predict the contents of R&WI’s 100th anniversary issue, but I am sure it will be an interesting one.
Congratulations, R&WI, on your 50th anniversary. RWI