Whirlygig: the troubled life of the J-2 autogyro

It seemed like a good idea at the time.

Shortly after the end of the Great War of 1914-18, a young Spanish aircraft designer watched one of his designs stall and spin to the ground on a test flight. Aircraft design had come a long way since that windy day on Kill Devil Hill, but the stall-spin accident continued to kill airmen and confound designers. Juan de la Cierva at once determined to create an aircraft that could fly at slow speeds without the danger of a stall.

Pitcairn
The “autogiro” was an innovative idea – but did it have a future in general aviation?

In the early 1920s he built such a machine. It had four long, thin “wings” that rotated about a central hub, spun by the flow of air through them as the aircraft was pulled forward by a conventional engine and propeller. Happily, these unpowered, free-wheeling wings provided both lift and directional control for sustained flight. Best of all, the autorotative force kept them spinning fast enough to prevent stalling even when the aircraft flew very slowly.

It was indeed a good idea, and de la Cierva named it “autogiro.”

There was sporadic interest in the autogyro concept in the 1920s and 1930s, until it was overshadowed by its powered-rotor progeny, the helicopter. The latter was more complex but had the advantage of true vertical takeoff and landing capability. Autogyros were at best short takeoff and landing machines, still needing some runway and clear approach and departure paths for their comings and goings.

While the helicopter flourished in the 1940s and 1950s, the state of the autogyro art languished.

Enter Robert Paxton McCulloch — flamboyant manufacturer, oilman and real estate developer, known both for chain saws and for transporting the London Bridge, stone by stone, from the River Thames to a remote Arizona desert.

Less well known was McCulloch’s interest in aviation, particularly rotary-wing aviation. As far back as 1949, McCulloch Aircraft Corporation was developing a light tandem-rotor helicopter called the MC-4. This was based on an earlier design called JOV-3, the brainchild of Drago K. Jovanovich, whose company McCulloch purchased. The MC-4 had promise, but failed to attract buyers.

By the mid-1960s general aviation was booming, but airplanes and pilots were still regularly coming to grief in stall-spin accidents. McCulloch sought to revitalize the autogyro concept for the mass GA market. Surely there must be demand for a stall-proof, slow-speed-capable flying machine that was both easier to fly and less complex than a helicopter.

Autogyro on ramp
You might not call it graceful, but maybe the J-2 was cute?

Designer Jovanovich, now in McCulloch’s employ, came up with a machine that, if not an aesthetic triumph, was at least “cute.” The egg-shaped fuselage housed two occupants side-by side, with a carbureted 180 hp Lycoming O-360 engine and wooden two-blade propeller in pusher configuration behind them. Attached was a pair of vestigial wings, 11 feet in span overall. Each wing contained a fuel tank and supported a tailboom that extended back to a small vertical fin and rudder, with a fixed horizontal stabilizer between the booms.

With some imagination it might resemble the tail group of a miniature Cessna Skymaster (I can’t bring myself to say Lockheed P-38). The aircraft rested upon an oleo-strut tricycle landing gear, and topping it all was a pylon reaching 8-1/2 feet high, from which blossomed the three-blade, 26-foot diameter rotor system. The fully-articulated rotor hub was the same as that on the ubiquitous Hughes 269A helicopter, though the metal blades were slightly longer and with an airfoil optimized for autorotation. The resemblance was natural, for it was the same Drago Jovanovich who had designed the rotor system for Hughes in the mid-1950s.

In the designer’s honor the new Gyroplane carried the model number “J-2.”

In 1970 McCulloch Aircraft Corporation set up a production line for the J-2. It shared McCulloch Motors Corporation’s new chainsaw plant in Lake Havasu City, Arizona – the city planned and promoted by McCulloch Properties on the shore of an artificial lake in the Colorado River. Just across a bridge – the London Bridge – from the plant was the airport where McCulloch International Airlines’ Lockheed Constellations and Electras brought thousands of real estate prospects for free tours. Seemingly everything in sight was one of Robert P. McCulloch’s good ideas.

And the marketing department went to work. Said one glossy brochure:

“Enjoy the speed and range of a light airplane . . . the spot takeoff and landing capabilities of a helicopter . . . and with the operating costs of only 1/4 of the most inexpensive helicopter. Now, virtually every open field, large parking lot or dirt road becomes an airport. You fly relaxed in the easiest to fly aircraft in the sky. It will not spin. In the event of power loss or sudden weather deterioration, the free spinning rotor permits you to sit down [sic] in the nearest open area.”

J-2 on snow
Not your average general aviation ad.

Accompanying the gushing text were photos of J-2s on a beach, golf course, construction sites, farms and ranches. Most creative of all was the staged shot of a J-2 perched on what appears to be a snowy mountain ridge, as a fellow with a medical bag hops out of the left seat to tend to a young female skier on the ground, leg awkwardly turned. Another pilot remains in the cockpit, raising the question — who gets left behind when the J-2 leaves?

Or the corollary question: can the J-2 leave at all?

The real-life performance data in the Approved Flight Manual is not as rosy as the ad copy.

With maximum gross weight of 1500 lb, a typical J-2 had a useful load of about 450 pounds. Cruising speed was 95 mph (Vne was 106 mph IAS, due to retreating blade stall), with fuel consumption of about 10 gallons per hour. Range was less than 150 statute miles with a 30-minute reserve. A contemporary Cessna 150 outperformed the J-2 in all these categories, at less than half the price.

And perhaps of interest to the mountain rescue pilot in the photo: “Maximum approved pressure altitude for takeoff 4000 feet; Maximum approved pressure altitude 8000 feet.”

True to the ads, the J-2 could land in a very short distance. Into a light breeze it could spot-land at zero groundspeed. But the ability to squeeze into a small space didn’t mean it could squeeze out of it. Per the manual, it took a ground run of 540’ to leave the ground on a calm, standard sea level day, and 1,150’ to clear a 50′ obstacle. Many fixed-wing lightplanes could easily beat the J-2’s takeoff performance.

The first production J-2, N4301G, serial number 11 (the first ten serials were reserved for pre-production prototypes), entered service at the end of 1970. It went to McCulloch’s first authorized dealer and school, Belair Aviation at Long Beach, California. Belair’s chief pilot, Ken McGuire, was trained at the factory to train other Belair instructors to demonstrate, sell and instruct in the J-2.

The first pilot trained in the J-2 at Belair seemed ideally qualified to be a gyroplane instructor, as his full-time job was flying a police helicopter. In late February 1971, on a dual instruction flight with Ken McGuire in the right seat, he landed N4301G on runway 30 at Long Beach with a light crosswind from the left. Upon touchdown the top-heavy J-2 suddenly swerved one way, then the other, then rolled over on the runway. The occupants were not injured, but the J-2 was heavily damaged.

J-2 rolled over
More than one J-2 ended up on its side after a landing mishap.

There was immediate speculation that the accident was caused, ironically, by the experienced helicopter pilot instinctively applying left pedal on landing. Just four days later, however, McCulloch test pilot Jim Reichert “duplicated the malfunction,” rolling over in N4304G (s/n 14) on the runway at Fox Field in Lancaster, California. Eventually the NTSB issued a report concluding that the probable cause of Reichert’s accident was, “Poor/inadequate design” of the landing gear and nosewheel assemblies; and “Design deficiency in nose wheel self centering device.”

In the meantime, however, there would be another mishap.

This is where I came in.

In the spring of 1971 I was a newly-minted CFI. I had taken my advanced training at Belair Aviation, and with the CFI ticket in hand, Ken McGuire invited me to come on board as a part-time instructor. As an additional incentive, I would get in on the ground floor of the gyroplane revolution! Ken said he would train me to be one of the first J-2 instructors. We started with an hour of dual instruction in N4303G on April 19, 1971.

Whatever the J-2’s shortcomings, it was a barrel of fun to fly. Nimble and responsive, with outstanding visibility, it felt like we were flying a giant honeybee around the Long Beach area.

A giant honeybee with a very loud buzz, that is. The J-2 was noisy outside, but deafening inside. Headsets were rarely used in light airplanes in 1971, but were absolutely necessary in the J-2’s ear-splitting cabin. Even with the headset, my skull echoed the noise and vibration for hours after each flight in the J-2.

Takeoff in the J-2 was a complex process, using a system of belts and pulleys to spin the rotor up to flight rpm before starting the takeoff run.

J-2 transmission lever
Engaging the transmission meant reaching over the pilot’s shoulder to flip a lever.

When ready for takeoff, the J-2 would be lined up in position on the runway with the brakes set and the engine at idle. The pilot would first lift a lever behind his head on the rear cabin bulkhead, engaging the transmission.

To the left of the pilot’s seat was a lever that looked like a helicopter’s collective lever, and operated somewhat similarly. It was called “rotor clutch lever” in the manual, but to us it was the “spin-up lever.” Like a collective, it raised and lowered the pitch of the rotor blades, but was spring-loaded in the “full up” position on the J-2. When lowered, the lever also engaged the spin-up transmission clutch. The pilot would begin slowly pressing down on the lever against the spring, engaging the clutch and gradually increasing rotor rpm.

It was a very strong spring that held the spin-up lever in the “up” position. By the time I had eased the lever all the way down, I was grateful to finally straighten and lock my quivering elbow to hold it there.

With the spin-up lever down and the blades in flat pitch, a twist of the throttle grip on the lever slowly added power to bring the rotor up to 450-500 rpm.   Then the spin-up lever was quickly raised all the way up, in one motion releasing the clutch, setting the now-freewheeling rotor to flight pitch, and relieving the ache in my left arm. The J-2 perceptibly raised up on its haunches, but not yet airborne. Immediately the twist-grip throttle was opened fully, brakes were released, and at long last the unmuffled exhaust stacks behind the cabin cacophonously trumpeted the start of a J-2 takeoff run.

Rotation was at 47 mph IAS. Once airborne, the aircraft was leveled to accelerate in ground effect to 62 mph IAS for initial climb, then Vy of 70 mph after obstacles were cleared.

This whole process tied up an active runway for about 45 seconds, if all went well. Understandably that did not sit well with ATC at Long Beach, then the fourth busiest airport in the country. Eventually they allowed us to use the south parallel taxiway for takeoffs. Landings, on the other hand, were a piece of cake. Tower usually cleared us to land on a seldom-used, 500-foot-long taxiway that led right to the Belair ramp.

J-2 spin up lever
It looked and acted a lot like a collective, but the lever on the pilot’s left side was different.

Initially I had difficulty adjusting to the J-2’s control sensitivity and responsiveness at various airspeeds – because they were always the same. I was used to controls in fixed-wing aircraft becoming mushy and less responsive as airspeed decreased. But since the gyroplane’s “wings” always have the same relative airspeed regardless of the forward motion of the aircraft, the controls worked the same at 25 mph IAS as they did at 90. That led to overcontrolling on many of my early (and some not-so-early) landings.

A J-2 can’t hover. But Ken showed me that it can “fly” at zero airspeed – going straight down in autorotation, in a level attitude, at about 1000 fpm, yet still in full control. Recovery from the zero-airspeed condition is similar to stall recovery in a fixed-wing – pitch down and full power. The maneuver requires additional altitude to complete, so you would be well-advised not to wait until all your options are above you before regaining speed.

Ken soloed me in the J-2 at Long Beach on April 30, 1971, with 9.5 hours of gyroplane dual in my logbook.

Five days later we flew N4303G to nearby Compton Airport for more pattern work. There was the normal crosswind from the left at about seven knots as I flared for landing on Compton’s runway 25L. We touched down at what seemed a slow walk, but as soon as the nosewheel touched the J-2 swerved violently to the left, to the right, to the left… and over it went.

I still remember thinking as we rolled: where are those rotor blades going?

Ken must have been thinking: not this again! Poor N4303G (did I mention it was serial number 13?) came to rest on its left side. The left wing was broken off at the tailboom, and the vertical tails were sheared off, but Ken and I quickly clambered out of the right-side (now top-side) door unscathed. The rotor blades were twisted and curled harmlessly. One of the weighted rotor blade tips was found several hundred feet away between rows of parked airplanes.

Six J-2s had entered service, and now half of them had rolled over after loss of control on landing. FAA promptly grounded what was left of the fleet. I felt awful that I had crunched one of them. But soon I was heartened by word that official attention was being focused on the design of the nosegear, as confirmed by the final NTSB report on Jim Reichert’s whifferdill in N4304G two months earlier.

J-2 autogyro cockpit
The cockpit of the J-2 resembled a small helicopter.

In short order, FAA approved a “fix” to the nosegear centering mechanism, J-2s were back in the air, and production resumed. At the end of May 1971, Winn Air Aviation of Van Nuys, California, became the first retail customer to take delivery of a J-2, N4309G (s/n 19).

Two months after my accident, I flew with company test pilot Bill Evans at Lake Havasu City to try out a J-2 with the modified nosegear, which turned out to be the repaired N4301G. Ground handling did seem a little better, but the inherent top-heaviness remained. Factory pilots had also noticed that the main landing gear oleo struts would sometimes remain extended on landing, or compress unevenly, making directional control suddenly unpredictable at a critical time. Though still not prohibited in the manuals, crosswind and soft-field operations were now being quietly discouraged.

That was the last time I flew a J-2. Our company soon lost interest in the program, and the gyroplane school went away.

A total of 85 J-2s were produced, the last in 1973. At last count NTSB has issued 30 accident reports involving J-2s. One particularly unfortunate J-2 was the subject of three of them. Most were takeoff and landing mishaps of various kinds, including five more rollovers. In two instances, mechanical issues caused the rotor rpm to decay in flight, resulting in forced landings.

However, owing to slow speeds on takeoff and landing, and a well-designed cabin structure, occupants generally fared well in J-2 mishaps. The only fatal J-2 crashes in the NTSB database were an inflight main rotor separation in 1989 (seized main rotor thrust bearing, beyond its allowable 300-hour service life), and a crash resulting from an unexplained power loss in 1994.

Just ten J-2s are still listed with valid registrations in the FAA database, plus one in New Zealand.

A few years ago Bill Evans shared with me some of his recollections of the J-2:

J-2 in Pima museum
The best place for the J-2 might be hanging from the ceiling of a museum.

“All in all it was a really fun aircraft to fly but had so many limitations when it came to performance. It had a very limited range with a lot of unusable fuel left. The required distance for takeoffs was far more than acceptable. We were able to land in off-airport locations but with the wood props it was usually an invitation to some major damage. We did experiment with a 200 HP Lycoming engine and also a 3 bladed constant speed Hartzell prop. These improvements helped a little but in the end, it still did not have the desired performance.

“One of the biggest problems was the noise. This really plagued the engineering department and nothing seemed to help. We had to wear special David Clark headsets and still the noise level in the cockpit was deafening.

“I remember talking with Ken McGuire after your accident at the Compton airport. I asked him what changes could be made to improve the J-2. He said, ‘Put wheels on the roof of it!'”

There is a new generation of light gyroplanes on the market, and an enthusiastic cadre of pilots who build and fly them. They tell me these new designs are safe, efficient, and overall a great improvement over the J-2. I’ll take their word for it.

A couple of months ago I paid a visit to the Pima Air & Space Museum in Tucson, Arizona, and laid eyes on a J-2 for the first time since that hot July day at Lake Havasu City in 1971. It was N4309G, hanging motionless from the museum’s ceiling, where it could do no further mischief.

Now that’s a good idea.

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