Podcast: Revolutions in Vertical Flight S1 E2: The Dawn of the Helicopter

Welcome to Shephard Studio’s podcast series on Revolutions in Vertical Flight, sponsored by our partner Bell.

Listen on Apple Podcasts, Google Podcasts, Spotify and more.

The Revolutions in Vertical Flight podcast tells the little-known story of the history of rotorcraft, from the autogiro and helicopter, to the tiltrotor and eVTOL platforms in development today. 

Revolutions in Vertical Flight reveals the stories of a small group of pioneers, the visions and beliefs that drove them, and their approach to invention and innovation.

And the Shephard Studio podcast series looks at the vertical flight innovation underway today, revealing how it will transform military operations and revolutionise urban mobility.

In this episode, we discover how a young engineer working out of his parents' barn was to profound effect on the future direction of the helicopter industry as well as the fortunes of a fighter aircraft manufacturer by the name of Bell.

And we hear the story of Frank Robinson, whose vision of a small, cos-effective helicopter was to entirely transform the sector.

Episode 3 - The Tiltrotor is here

A transcript of this episode is below:

In 1938, Igor Sikorsky was trying to convince his bosses to back the design that would become the basis for the modern helicopter. But 150 miles away, a young engineer working out of his parents' barn was about to perfect a similar design, one which was to have an equally profound effect on the future direction of the helicopter, as well as the fortunes of a fighter aircraft manufacturer by the name of Bell.

Young: “They wanted to apply that technique and I wanted to apply my technique of working with my hands and getting something to operate it. So, there was a real clash.”

Arthur M. Young was a native of Philadelphia who had studied mathematics and Princeton, but who possessed a very strong urge to invent something radically new. After a lot of self-searching in December 1928 Arthur Young decided he was going to invent and build a helicopter. He started traveling extensively up and down the East coast of the United States learning all he could about the helicopter patents filed up to that point.

His friend and colleague Bartram Kelley speaking in 1977 picks up the story.

Kelley: “He would check into a hotel room and spend his days in public libraries looking up all the entries he could find under the word helicopter. In this way, he became well versed in the patent literature and the history of early helicopter research. He found that a helicopter had succeeded in hovering for a few minutes in Ohio in 1923 and he read accounts of the experiments of many pioneers in the field. His next step was to set up a small aeronautical laboratory in the barn of his family's home in Radnor near Philadelphia. In 1929 if you announced that you were working on a helicopter, you were considered eccentric to say the least and if you are a young man of independent financial means as Arthur Young was, it took lots of courage and persistence to devote your full energies to what was thought of as a crazy invention. But persist he did.”

Welcome to Shepard Studio Revolutions in Vertical Flight brought to you in partnership with Bell. Over the course of six episodes, we are looking at the history of vertical flight and discover the key pioneers and revolutionary moments that created the rotorcraft industry we know today. And we consider the future revolutions, how next generation rotorcraft will shape the future battlespace, and hear how innovation underway today will enable the urban air mobility of tomorrow.

From his parents’ barn Arthur Young spent many years building model helicopters from parts sourced from toy shops and hardware stores. Unlike other helicopter pioneers, he never attempted to build a full-scale prototype during this period, preferring instead to trial and refine his designs using electrically powered models that he could control with wires.

Here we are able to hear from Arthur Young himself about the advantage of this approach, thanks to archive recordings provided by the team at arthuryoung.com.

Young: “I think I was exceptionally lucky in my different approach to the helicopter problem. Now Sikorsky did have the first helicopter in this country, no question. But I'd actually been working longer on the helicopter because I started in 1928. I don't think he started until about 1936 or 33, 35 maybe. And he immediately got into problems of control and actually he had the control wrong, 90 degrees out of face. He was bound to have trouble, but he, he first had extra rotors on the tail to tip it and then another to tip it forward. Whereas I went through all this routine of different types and different controls with the models. So, when I hit the full scale, we had the helicopter flying about a year after we started making it.”

But what motivated Arthur Young in those early days, during the years of toiling with models in his barn? The man himself never had much time for the question of what his helicopter would actually be used for.

Young: “Way back people used to ask me what, what would be the use of a helicopter when I was trying to make models and stuff? And I was very impatient with that. Trying to answer that question. It had nothing to do with what I was doing. I was trying to make one that worked. What people did with it I didn't really care.

“So, I prepared a stock answer. It would be invaluable for oiling weather veins. And actually, it wasn't such a silly answer after all because one of the first uses that they made of the helicopter was to blow the dew from cherries. And that's a little more ridiculous than oiling weathered veins. I mean, you wouldn't think of it, but actually they saved like a $6,000 cherry crop, one half hours flight. They just blow over the orchard and blow the dew - see the dew collects on these ripe cherries and breaks, this gets drawn into the cherry and it breaks the skin so they're ruined. But there are many other strange uses that helicopter was put to.”

By 1941 after years of focusing on the problem of stability, Arthur Young had a model helicopter that could hover well, and had enough control that he could fly it in and out the barn door. Word made its way to Larry Bell of Bell Aircraft, who arranged for a demonstration to take place at his Buffalo plant.

At the time Bell Aircraft was a major producer of war planes, building thousands of fighter aircraft and bombers for the war effort. But Larry Bell knew there would be a huge drop in production once World War Two ended.

He had also seen the Focke-Wulf Fw 61 on a pre-war visit to Germany so understood the potential of the helicopter. Bell took a personal interest in Arthur Young and his helicopter design as a potential future revenue stream.

Young: “When I arrived at Bell, September the third 1941 I was coming by invitation of Jack Strickler who'd heard about this thing from a mutual friend who told him I had a helicopter they would fly around the barn and out the door and back. So, I felt that I should have access to it so the guard wouldn't let me in. I was infuriated and I asked the chief of police, and I said, ‘call your dogs off. I have a helicopter here’. But the cops thought it was a bomb or something in the suitcase and he didn't want to let me in. Of course, when he, the chief told him, let me in, and it was all right, but actually it was a sort of a bomb, a time bomb because Bell Aircraft ultimately became Bell Helicopter. Well, shortly after that I met Larry and I took a liking to him right off and we made a deal and I signed my patents to Bell and they agreed to make two helicopters and I wanted to, because I expected the first one would be wrecked. And I think the budget was $250,000.”

The agreement struck, Arthur Young immediately ran into a clash of cultures. Unsurprisingly, the man who had spent years working in his barn found that a manufacturer, which produced hundreds of aircraft per year at that point, did things slightly differently.

Young: “The budget $250,000, that was okay. I looked and realized it was for drawing two helicopters not for making them. And this was not what I wanted to do. I didn't know how to draw it. I had to make it first and get it to work and then I could draw it. And so, I went to the head of manufacturing who spoke my language, rescue Creighton[TS1] , told him what the story was. I wanted to make two helicopters. He undersigned a guarantee that I would do it for the price mentioned and put the proviso at the bottom provided the engineering department had nothing to do with it.

“Ah, you see, I found myself in quite a predicament at Bell and let me recapitulate because the two different ways of thinking about the problem there was a real confrontation there. I'd been working on my own for 12 years and except for making sketches and having, oh, maybe a school course in mechanical drawing. I didn't know boo about drafting, but Bell aircraft was set up with the drafting department as top dog. They would draft their airplanes and that meant very careful contour lines to provide the streamline shape and then they had to make dyes to this. It, it was a, a very difficult technique which Bell was very proficient at.

“They wanted to apply that technique and I wanted to apply my technique of working with my hands and getting something to operate it. So, there was a real clash and since they were not going to do anything anyway, I of course won because I would just start to do something and that would be it.”

Moving into an empty car dealership in Gardenville, New York, Arthur Young and his team set out to build what would become the Model 30 helicopter. To ensure stability, the helicopter featured a teetering rotor as well as Young’s bar-like stabiliser bar on the rotor mast. The use of a stabilizer bar and flywheel had improved stability and pilot control on Young’s earlier models. And so, it proved with the first two Model 30 prototypes.

But still Arthur Young was not satisfied. While Larry Bell wanted him to concentrate on designing a four passenger, family-sedan type helicopter, Young secretly built a third prototype. This would incorporate all the design lessons they had learned and would ultimately result in the iconic Bell Model 47. Which in 1946 became the first ever helicopter certified for civilian use.

Young: “This question of design, eh, the first helicopter's the ship model 30 had a streamline nose cone and a streamline tail comb. And then the ship two which was tend to carry two people was supposed to look like an Air Cobra, also had streamline nose and the streamline cabin. And the third one, the one I mentioned that we were not supposed to make, which was to incorporate the best practice – we were in a hurry and we just didn't bother with the body. We just made it out of tubing. And it was powerful enough to carry two people.

“So, and it coincided with the time when they stopped making the Air Cobras. So, everyone wanted a ride. This was the new product and they all had their ride with nobody at all, just like flying around, sitting in a chair. And it was a very thrilling experience. The bubble was a happy thought from Joe Parish, who is one of my assistants. Joe dealt with plastics and he really loved plastics. He had this idea of blowing a bubble and I thought it was great because personally, I preferred nothing just going up in the air with without even a floor, just had these seats flying through the air. And this chair was a wonderful sensation, but you had to have some kind of protection when you're flying 80 90 miles an hour.

“In fact, there was a story about this, the early one in which we demonstrated we had nothing and someone said to Larry, when are you going to get a windshield for the helicopter? And he said, would you have a windshield on a horse? That was the spirit of those early flights. It was more fun without anything, but I saw the bubble was a great idea.”

Other design choices saw the third prototype fitted with skids, rather than wheels. This helped to reduce accidents but also lightened the helicopter, making it cheaper to build and operate.

A further design choice saw Arthur Young clash with his boss. Larry Bell wanted the helicopter to have a streamlined and covered tail boom, rather than the exposed welded-tube tail boom preferred by the practically-minded Arthur Young. Those that can summon up a mental picture of the Bell 47 know who ultimately won that debate.

Young: “Of course we were still trying to make the ones that management preferred, which was the one with the body. Lowy [TS2] who was this Detroit big time designer, worked with me and me turned out the best we could, trying to make it look streamlined the way things were supposed to look in those days. But the body added to the weight, it took longer to had to take the panels off to work on the engine and it decreased the visibility and also the covered tail made it difficult to fly backwards because it would weather vane around.

“Sometimes, it wasn't essential, but it was desirable to be able to fly backwards. Suppose you wanted to come in and hover and the wind was blowing the opposite way to from the back. And you couldn't do it with the body, with a covered tail tailbone. I remember Larry said that uncovered tails, the pilots fly much more dangerously with it. I said, no, they're not flying more dangerously. They're just, they don't have to. They can take more chances because it's safer. But any case, the customers eventually decided the issue because they wouldn't buy the one with the body and the uncovered tail boom won. Larry he was famous for his grandsirs. He said, I never want to see the sun set through the tail of a Bell. How I, well, he'd misunderstood the thing about sun never sets on British soil. That meant that the British soil was everywhere. Well, as it worked at the open tail was everywhere.”

More than 5,600 Bell 47s were eventually produced, including those under license by Agusta in Italy, Kawasaki Heavy Industries in Japan, and Westland Aircraft in the United Kingdom. The aircraft was the living embodiment of the helicopter for viewers of the TV action series Whirlybirds in the 1950s and for later generations raised on reruns of M*A*S*H.

The functionality of Arthur Young’s design was such that the New York Museum of Modern Art has put the Bell 47 on permanent display. Here’s what the museum has to say about the helicopter:

“While the Bell-47D1 is a straightforward utilitarian craft, its designer, Young, who was also a poet and a painter, consciously juxtaposed its transparent plastic bubble with the open structure of its tail boom to create an object whose delicate beauty is inseparable from its efficiency.”

This didn’t happen by accident, as Arthur Young explains.

Young: “Well, the other thing that I wanted to stress about designing was it these efforts to make the right shape, body streamlined shape body. It was as though you got the body and then you put the rotor on it and then put an engine in to drive the rotor. You put these accessories into the body. Well, I thought of it the other way around. You see with my models, I'd started with the motor and put the transmission on the motor and the rotor on top of the transmission so that it was all a unit and the pilots or the passengers where the accessories you just hung up, put a seat on and put them there and there you had it.

“So, approaching it in this other way of, of the heart of it was the engine and the transmission and the rotor hub and then what else do you need? Just something to accommodate the pilot and that is what I mean by having it design itself. You're not trying to impose say the idea of an airplane onto a helicopter.”

Achieving a goal he had set himself almost 20 years before, Arthur Bell left the helicopter business in 1947 in order to resume his study of human consciousness. Visitors to Arthuryoung.com, which generously gave us permission to use their archive footage, will find more Arthur Young interviews on consciousness, evolution and the philosophy of science than on helicopter design.

Young: “The ego's a very useful tool. It's a vehicle, it's a form, but to be stuck with that form is death. Purpose can find that shown vehicle whenever it wants. In fact, it creates its own vehicle given an opportunity.”

But his work set up Bell Aircraft as a major player in the helicopter business, resulting in other iconic aircraft such as the Huey, Jet Ranger and Cobra.

That heritage started by Arthur Young, that love of the unique capabilities of the helicopter, runs through the company today.

As Erasmo Pinero, a flight engineer at Bell explains.

Pinero: “People that work in this industry really like helicopters. The people that are started Bell into the helicopter feel in 1946 or 1945, 1946 at the end of World War Two didn't really know what to make of the new machine called the helicopter. Right. Sikorsky was doing some experiments obviously, and the Europeans have done some experiments, but then they came to, they were not really a strong force yet to be reckoned with. And the Bell guys that were involved in these early helicopters experiments really, were beginning to fall in love with the technology where we're discovering it and at the same time falling in love with it.

“And then it began a new generation with a new generation of engineers and enthusiasm within the company that has not stop. The people have come to work for Bell because they like helicopters. As we all know, the helicopter today is a very indispensable vehicle for everything. It has saved thousands of lives. It keeps savings life every day is how we actually speak right now. You know, so in that sense, our industry is a very unique one.

“And the people that work within that industry, whether you're working for Sikorsky, whether you're working at MD Helicopters or Bell, whatever, are, are very, very much into that kind of a machine.”

Igor Sikorsky, Frank Piasecki and Arthur Young with support from Larry Bell. Along with Stanley Hiller Jr, who developed his prototype Model 360 helicopter in the late 1940s, these early pioneers laid out the main tracks of helicopter design.

As James Chiles points out in his excellent history of the helicopter, The God Machine, their designs and layouts are still visible in all the helicopters built today. Stanley Hiller was also motivated by creating a family copter, initially developing the coaxial XH-44, which certainly had the looks of a commuter aircraft from the future.

Remarkably at the age of 19, Hiller designed, built, and test flew the first helicopter with coaxial rotors to fly successfully in the United States. The XH-44 was also the first helicopter to fly successfully with all-metal blades and a rigid rotor. But the personal aircraft boom that had been forecast for the post-war period did not materialise. So, Hiller decided to adopt the single main rotor with anti-torque tail rotor configuration for his next design, the UH-12. This highly successful helicopter was to have the longest production run in history. For now, the idea of a low-cost, family helicopter would have to wait.

The next major revolution in helicopter history happened under the hood. Developed by Charles Kaman, the K-125 and the later K-225 featured intermeshing rotors and Kaman's patented servo-flap stability controls. In 1951 a modified K-225 equipped with a Boeing 502 turboshaft engine became the world's first gas turbine-powered helicopter to fly. Gas turbine engines provide a sustained high-power output and high reliability, while being smaller in size, and light weight - perfect for helicopters. In Europe, Turbomeca developed the first turbine engine to enter production in 1955 on the Sud-Aviation Alouette II.

Here’s Mike Sousa, director of turboshaft business development at General Electric.

Sousa: “Well certainly going to a gas turbine engine in the helicopter was something that allowed the engine weight to go down dramatically and that made a huge difference in terms of what the capability of the helicopters can do. So again, that was one of those things that way back in history happened and made a huge difference. And since then from an engine standpoint on helicopters, you know, when the T 700 was introduced, it was about a 25% improvement in specific fuel consumption.

“And that made a huge difference in terms of what you could do in terms of the capability of the aircraft. And again, today when you introduce an engine like ITEP, you're talking about another 25% improvement in specific fuel consumption. And it might not be the same order of magnitude of capability benefit, but it is certainly going to increase the capability of those helicopters dramatically.”

Champion: “Yeah. And I would just echo what Mike said about the change from a reciprocating engine to a gas turbine engine.”

That's Tom Champion who is program manager for the new ITEP engine at General Electric.

Champion: “You know, I, I'm a former army aviator and I went to flight school at a time where the army was trying to figure out what to do with all these old Hueys that they were taking out of service as, as the Black Hawks came in and they decided to start teaching army aviators on the Huey.

“And so, I was early in that process. Prior to that, they, they first learned on a Ph55[TS3] , which had a reciprocating engine and you know, it wasn't necessarily governed. So those older pilots had to learn how to, you know, manually manipulate the, the throttle every time they were making any control input that changed the power demands. And I didn't have to deal with that because the Huey had a governor. And so that, that really was a revolutionary moment in, you know, vertical take-off.

“And then the T 700 the other piece, not only did it have a significant you know, SSC improvement, but you know, it was designed in the aftermath of the Vietnam war where sort of the first generation of turban engine powered helicopters just saw a ton of service and lots of lessons learned. And so, Mike had alluded earlier or talked about earlier about the modular maintenance capabilities of the T 700 that we preserved with the T901. And that from a logistics perspective was a really a revolutionary point in how those engines on helicopters get serviced in the field.”

For our next big moment in the history of the helicopter, we have to jump forward to 1973. When one man’s vision of creating a simple, no-frills but reliable helicopter with room for one pilot and one passenger, has perhaps come the closet to the family helicopter envisioned by the early pioneers.

But Frank Robinson’s chance to achieve this dream were ultimately to rest on the verdict from a jury of his peers.

This is Frank Robinson speaking to the Royal Aeronautical Society in London.

Robinson: “When I was about nine or 10 years old, I saw a picture in the Seattle newspaper of Igor Sikorsky hovering his VS-300 prototype and it really converted me very totally, very quickly. I think I have that here. Yeah, there he is. And what really got me is that in the caption underneath the photograph he described what he could do is that helicopter, he could go up or down. He could go forward or backwards. You said rotate it any direction and I was just so overwhelmed because I had no idea that anyone could build a heavier than air flying machine that could do have all that freedom of flight and it made me an absolute convert for life. So right then and there I decided that's what I want to do. I'm going to have to get into that industry and I'm going to have to make a contribution to it.”

The story of how Robinson got his two-seat piston-engine R22 into production is an advertisement for simplicity in design, the benefit of keeping faith in the concepts you know will work, and, in particular, how far determination can take you.

From small beginnings, designing the R22 in his Californian garage from 1973, the success of that helicopter and later the R44, saw the company go on to produce more helicopters annually than all other North American manufacturers combined.

Robinson: “And it was kind of unusual because I had always heard that if you don't, if you haven't started your life's work by the time you're 40 years old isn't going to happen. So, forget it. Well I was already 43 but by the time I did that and already three years past due, but I did, I did it anyhow and it, it all worked cause I wanted at that time to do the very same thing that I eventually did do. I wanted to design a very simple with the emphasis on simple low-cost helicopter is that it could be produced efficiently and could be sold to the public at a price that many people could afford. And so, I decided to follow that career.”

Born in Washington State in 1930, Robinson was a child of the Great Depression. His course firmly set by that early exposure to the VS-300, Robinson was able to save enough money to enrol at the University of Washington and major in mechanical engineering, with graduate work in aeronautical engineering at the University of Wichita.

Upon graduation in 1957, Robinson immediately applied for work with every company involved in building smaller helicopters. Impressed with his application, Cessna Aircraft offered him a job working on the CH-1 Skyhook four-seat helicopter - the only rotorcraft ever built by the company.

So began a 16-year period where Robinson developed the skills that would later prove so vital, while at the same time carefully avoiding becoming too specialised in any one area of helicopter production.

Robinson: “All told, I actually worked for six different helicopter manufacturers to try to get all of the different experience that I felt I needed cause I really wanted to do what I eventually did, which was to start my own company and design my own helicopter, so a total of six different helicopter manufacturers over a period of 16 years to get the experience that I felt I needed.

“And in each case, I would work at the company and if they tried to specialize me in one area, I would, I would, I wouldn't buy it. I didn't have any money and I was not too long divorced. I had three kids. And so, it was quite a challenge to take on starting a company on your own and with no other source of income. This was the house that we lived in at that time. It was located in Palos Verdes, is there in the South part of Los Angeles, just a small tract house. And we had to clear out all the furniture out of the living room and the family room and, bring in some drafting tables and other things that we needed to continue with that project.”

Robinson describes the year spent assembling the R22 prototype as the happiest time in his whole life, the perfect job for a man with a vision who loved working with his hands.

While the build would eventually move into a tin hangar at Torrance Airport, the initial work that took place at Robinson’s garage put him first at odds with his neighbours, and then the authorities, which fined him $800 for violating local zoning laws.

Unable - and unwilling - to pay the fine, Robinson elected for a jury trial and set out to defend himself.

Robinson: “As a matter of fact, they complained to the zoning commission, what I was doing, and the zoning commission for the County ordered me to cease and desist and all that nonsense. And furthermore, they said that there, that I had would have to pay a fine for having violated their zoning commission rules. I can't remember for sure, but as I recall, I believe it was $800 and I didn't have $800 to give those people at that time or serve eight days in jail.

“So, they had a couple of different alternatives there that I could, that I could accept if I decided to go to trial. So, when I was called in front of the judge, he asked me, how do you plead? And I said, not guilty. Well, I was just guilty as hell. I knew it. Everybody else knew I had violated their zoning rules. And furthermore, I said, and I demand it not only at trial, but a jury trial.

“The judge was, okay, that's your right. And as, Oh, and one more thing, your honour, I would like to act as my own attorney. And so, he agreed, he agreed with that as well. And so, we went ahead with that trial and I had to call my witnesses and they called their witnesses and it went on and they, we had to set a seat, the, the complete jury. And I had to get up and give my side of the whole thing. Then I just got up and told them every, told the jury exactly what I was doing and why. And didn't minimize anything. It didn't in any way say anything to, to try to make myself look innocent cause I knew I wasn't.

“And the jury, they went out and I think they pondered it for about, I don't think I, I don't think it was even much more than one hour or at the most two. They came back and they found me innocent.”

Work continued, and in 1975 the prototype was finally ready. Constructed of aluminium and fibreglass, the aircraft featured a 150hp Lycoming flat-four piston engine, a semi-rigid two-bladed main rotor and a two-bladed tail rotor.

The main rotor featured a teetering hinge and two coning hinges. Curiously, the tail rotor blades on early R22s were cured in Robinson’s oven while he ate his dinner in the evening.

Robinson: “And it had a wraparound aluminium skin and the whole thing was bonded with the high strengths structural adhesives that we use on the main rotor plates. But it had to be cured at about 260 degrees Fahrenheit for at least an hour and get that temperature had to be very accurately controlled because you had to heat it up at the right rate, who went down at the right rate and so on.

“So, I designed a jig to lay those parts up here that would fit, actually would fit inside the oven in my kitchen stove. And it worked out pretty good because what I would do each night, I would lay up one of the tail rotor blades, all those individual parts put in, it was their adhesive on them, take them, take it home with me that night, put it in the kitchen stove and turn on the oven. And while I was eating dinner, have it cured and I was sitting right there so I could monitor the temperature.

“I had a real good and reliable pyrometer so I knew I could monitor the temperatures very accurately. And that's how on the early R-22 it was. I don't know if any of you guys ever flew one of those, but that that's how the tail rotor blades were put together on it and we never had a single problem with any of them. They worked just fine.”

Another distinct element of the design is the T bar cyclic control.

“There are other things that we have used along the way. This is the T bar cyclic, which is both loved and hated by some of the pilots out there, although I don't think anyone’s saying they hate it anymore. They've gotten used to it and there, and they actually like it when they get used to it because it has some real advantages for the pilot. The reason for it was to desensitize the lateral control of the helicopter. It also has some other advantages. For instance, getting in and out of the helicopter. You don't have to climb over a cyclic stick like you do on other helicopters.

“You just climb it and put your feet on the pedals and you're there. The others all have a control that comes up right from the floor all the way up to here and so on. And the same on this side, so it has a leverage based on the other helicopters with floor mounted cyclists. It's a leverage based on that for running of the cyclic.

“In this case, we don't have any, any leverage because it's completely free and as the pilot moves his lateral, his cyclic stick left or right, he can glide over the top of the pilot's knees to get the additional control travel. So, it's worked very well and it hasn't changed, but you could see the R-22, that's what it looked like the R-22 I flew back in 1973 or 75 rather. And works the same way there and now here in the R-66 is that we, we're flying today. Here's that same control works just fine.”

Finally, in 1975 it became time to take the R-22 out and test its various systems. And once Frank Robinson ran out of systems to check, the day also became the moment of the R-22’s first flight.

Robinson: “So that was a prototype and that was the prototypes that finally in 19, the summer of 1975. we took the prototype towed it on that little trailer that it's sitting on right to here, down to the west end of the field.

“And I started to run it up, checkout to clutch engagement, check out all the different systems now if we were a bigger, larger company we would hate to take, we would spend at least two or three weeks or a month or more checking something like that out before we ever tried to fly it.

“But we didn't have that kind of time to waste. And so, the first days that I had it down there at the west end, we started going to all the different systems on it and they all seem to work just like they were supposed to. So, the, I was just right around noon or a little after that. Frankly, I'd run out of things to check.

“So, I told the guys to take the blocks out of the controls. We had a control box that held those controls and being able to move anywhere on their own and to get back. And so, they, they pulled the blocks out. I waved them all to get a good distance away from the helicopter cause I wouldn't do the, the tethered tests like it was so normally done in the other companies where they would actually have your machine tethered down so it couldn't go anywhere except for the tethers allowed it to go. And I went ahead and started to pull in the engine, the RPM started to pull in the collect even it felt just fine.

“I went ahead and just lifted it off and it was started to hover it and hovering it around the area for a bit and did some hover air taxing with it and it works. It worked fine. And that said that was the first site. That was in August of 1975.”

From such beginnings, the company quickly become a major supplier of helicopters. The 500^th R22 was delivered in July 1985 and Robinson Helicopter Company has continuously produced more civil helicopters than any other manufacturer since 1987.

While the extent of the R22’s uptake might have come as something of a surprise to Frank Robinson, the elements of the aircraft’s design that helped contribute to this success were unquestionably deliberate.

Always striving for simplicity, Robinson envisioned an aircraft that would be robust, and require little maintenance.

While the R22 was finding homes in flight schools, flying clubs and farms around the world, the helicopter industry continued to grapple with a fundamental problem - how do you extend the speed and range of the rotorcraft without losing its unique vertical take-off and landing attributes?

The determination of one military service to revolutionise the way they conduct operations was to pave the way for one elegant but controversial solution.

Step forward the tiltrotor.

That’s next time on Revolutions of Vertical Flight.

Revolutions in Vertical Flight is brought to you in partnership with Bell- a huge thanks for their support. Thanks also to the Royal Aeronautical Society, the Vertical Flight Society and the Arthur Young society for their assistance and access to their archives, as well as to Elfan Ap Rees and the staff at the Helicopter Museum. In our research, we found The God Machine by James Chiles extremely helpful and it's an excellent read.

Revolutions in Vertical Flight was written and produced by Tony Skinner with script assistance by Gerrard Cowan and audio edits by Noemi Distefano. And I'm your narrator, Gennifer Becouarn. Until next time.