What Happened to the Helicopter? | Esquire

What Happened to the Helicopter?


Whirling rotors pique the imagination, but remain a dream for the average man


CLONEL H. F. GREGORY, then chief of the Miscellaneous Projects Branch of the Army’s Materiel Command, was coming in for a landing at Wright Field. When he called the tower for permission to land, the operator said, “Sure, but where are you?” Whereupon, Gregory, who had been hovering directly over the tower roof in his Sikorsky R-4 helicopter, suddenly popped out of his hiding place to the astonishment of the tower operator.

Gregory’s little prank is typical of the now-you-see-it-now-youdon’t field of vertical flight. Ever since the day in May, 1940, when Igor Sikorsky, the great airplane designer and manufacturer, jammed on his upturned fedora and lifted his helicopter from the ground in its first public demonstration, the man in the street has been in a dither. Though Sikorsky was taking justifiable pride in demonstrating an idea that he had first tried at bis Kiev home in 1909, the spectacle of the man in a fedora sitting calmly at the controls of his helicopter conjured up visions oi roof-top landing fields, aerial commuting and backyard flying machines.

Quick to see the commercial possibilities of the whirligig, a motley crow d of opportunists scrambled on the bandwagon. But the immediate nation-wide acceptance of the helicopter by the man in the street scared the wits out ot the helicopter people, who felt that the machine was not yet ready for a commercial debut. Ever since, we have been treated to the remarkable spectacle of high-pow er publicity men trying not to get publicity. To liven the screwball situation, the noisy helicopters would not be shushed. The Navy landed them on platforms on ships in convoy, the Coast Guard pulled spectacular rescues with them and the Army used them to pick up airmen stranded in the inaccessible forests and mountains of India. Helicopters even played a part in the bombing of Japan. V hat, then, is the truth about the helicopter?

Any flying machine that can rise and descend vertically, hover over one spot, slow’ down and stop, and fly sideways or backwards obviously has a great future. The helicopter, unfortunately, does not have behind it forty-odd years of trial-and-error evolution like the airplane. It has serious “bugs,” but thanks to pioneering done on the airplane, engineers are tackling these difficulties with an aggressive confidence.

Yet, the basic principle of its operation is so simple that, in the fifteenth century, Leonardo da Vinci was able to sketch it and to make the following notation: “This instrument, made with a helix, is well made, that is to say oí flaxen linen of which one has closed the pores with starch, and if turned with great speed, the said helix is able to make a screw in the air and to climb high.” But many a heart has been broken and many a fortune lost trying to make that simple idea work.

The Sikorsky-type machine has a big threebladed rotor whirled by a motor inside the fuselage or body. To prevent the machine from revolving in the opposite direction, Sikorsky dreamed up one of his largest contributions in the field of vertical flight—a small tail propeller which does not push or pull in the usual fore-and-aft direction, but instead pushes against the side of the machine. By controlling the thrust of this little tail propeller in flight* Sikorsky could keep his machine headed where he w anted it. To travel in a chosen direction, he used a control that caused the whirling rotor to incline by increasing its lift at a given point in its rotation, thus tipping the machine and sort of sliding it along.

A helicopter is extremely difficult to fly. Where the airplane can be flown “hands off” because of its wheel or stick control and rudder pedals, the helicopter requires constant use of both hands and

feet! Your right hand works the stick that tilts the rotor, controlling the direction of flight. Your left hand works the pitch control (the throttle is a grip on this second stick) which changes the angle or “bite” of the whirling blades. This “bite,” and consequently the throttle setting, must be changed constantly for climbing or descending. Your feet w ork the pedals that adjust the little tail prop, keeping the vehicle from turning like a pinwheel in the air. Colonel Gregory once described this process as something like trying to stay on top of a huge rubber ball.

The fact that helicopter controls operate differently from standard airplane controls embarrasses many a pilot who learned to fly on conventional aircraft. For instance, a landing in an ordinary airplane is accomplished by pulling back the control stick during the last few seconds of flight. This stalls the machine so that it makes sure contact with the ground. But pull back the stick on the helicopter and the machine rises. Once, when Charles Lindbergh was learning to fly the helicopter, he approached a field, forgetfully pulled back the stick as he had been doing for years, and promptly was w hisked up and back into a field behind him.

You can solo a light.plane in from five to twelve hours, depending on the make, but you would need about forty hours for the helicopter. While most airplanes have three controls, and a few have two, the helicopter requires four.

The helicopter is complicated. For aerodynamic reasons each of its rotor blades must be hinged to the hub so that they can “cone” or rise upwards. In addition, each rotor blade must be pivoted at the hub. In the event of engine failure, the rotor must be capable of “autorotation,” a sort of “freewheeling” or windmilling condition, where the blades continue to w hirl because of the blast of the wind. Autorotation permits the craft to descend like an autogiro, whose “windmill” is not connected to a motor at all. But the rate of descent of the helicopter with power off is close to thirty feet per second. Very little is known about the concentration of forces on the complicated rotor assembly, largely because in the helicopter gears, ball bearings and other parts are put to new uses. The rotor is given to vibration and, so far, it has been neces{Continued on page 190)

{Continued on page 190)

What Happened to the Helicopter?

Continued from page 59

sary to restrict the helicopter speeds to avoid rotor blade failure in flight. Ground resonance, a peculiar beating of the blast of air from the rotor against the earth when the machine is grounded, or hovering just off the ground, can induce vibrations that have caused at least one manufacturer’s experimental helicopter to shake itself apart before getting into the air.

Since most of the helicopter’s power is required to sustain its own weight, comparatively little of its horsepower contributes to forward flight.

There are light planes that can travel with four people at better than 150 m.p.h. on half the power. Whereas the average helicopter has a range of from 150 to 300 miles, there are light planes of 100 h.p. that can make hops of three to four hundred miles. Icing is the helicopter’s mortal enemy, for ice sliding off one rotor blade causes an unbalanced condition that can rattle the machine to pieces.

Because it is difficult to manufacture, the cheapest personal helicopter that we are likely to see in the near future will cost about three to five thousand dollars. In contrast, a good light plane costs about 2,000 dollars when it is produced in quantity.

Despite its “bugs,” however, the helicopter proved its value by its spectacular war record, indicating how we can expect it to be used in peacetime aviation. On April 19, 1945, a Canadian Canso (Catalina amphibian) crashed on a snowbound patch in remote Labrador. Before softening snows prevented ski-equipped rescue planes from landing near by, two injured airmen were successfully flown out. Then one of the rescue planes cracked up, adding two more victims to the marooned party. What followed was one of the great air achievements of the war. Like the U. S. Cavalry in an old western thriller, the helicopter saved the day. The Coast Guard had a helicopter at Floyd Bennett Field in Brooklyn. An Army C-54 transport flew to Floyd Bennett where the dismantled helicopter was stuffed into its spacious cabin and flown pell-mell to Goose Bay, Labrador. There, Lt. August Kleich of the Coast Guard made nine 150-mile trips to the crash scene, rescuing one man on each trip. If it had not been for the whirling angel of mercy, the crash victims would have been marooned for another thirty days until the thaw permitted pontooned planes to alight on the lakes.

Back in the dark days of May,

1943, when German wolfpack submarines were raising hell in the Atlantic, the Army Air Forces, the Maritime Commission and the War Shipping Administration made a series of tests to prove the usefulness of the Sikorsky helicopter as an anti-submarine weapon. On May 6 and 7 of that

year, Colonel Gregory made twenty-four landings and take offs from a 78 x 48-foot platform mounted on a Liberty ship. This stunt was to pay off.

During our B-29 operations against Japan from Guam, Saipan and Tinian, maintenance and repair of the monster war birds became a threatening bottleneck.

In desperation, the Army converted some Liberty ships into

floating repair depots, fully equipped to do almost anything and everything for the superbombers. There was one hitch, and that was the problem of getting parts and tools, back and forth between the ships and the damaged planes. Again the heli-

copter came to the rescue, taking off and landing on the ships’ small platforms. Whenever a B-29 crash landed, a helicopter flew to the site, where an examination was made and repair planned.

Over in the CBI theater, the 14th Air Force was looking for some means of evacuating fliers

who were downed crossing the Hump. Three four-engined transports, stuffed with the pieces of several new and more powerful Sikorsky R-6’s, flew 14,000 miles from the United States. Then, on April 4,1945, Lt. Murdock, Air Jungle Rescue Unit, effected the first helicopter rescue in that theater by picking up an ATC crew who had bailed out in the Burmese jungles. Feats of this

kind proved the worth of what the boys jocosely called the “eggbeater” or “animated palm tree.” While these exploits give an inkling of how we can expect to use the helicopter, it would be so much wishful thinking to prescribe the machine as a panacea

Continued on page 192

What Happened to the Helicopter?

Continued from page 191

for all problems. A sheep-herding association may find it an answer to a prayer, but those much-advertised roof-top landings will prove troublesome. Narrow streets and tall buildings create violent air currents. Nevertheless, roof landings figure in plans of some route applicants.

Its builders claim that the Piasecki (PV) helicopter (the banana-shaped model seen in the newsreels, which has a rotor at each end, seating ten passengers amidships) could be operated between, say, Idlewild and New York City at 4.9 cents a seat mile, or one dollar and fifty cents for the trip. Present airline connection bus rates would be one dollar and twenty-five cents.

Robert Wolf, chief product engineer of the Bell helicopter, believes that in the immediate future the whirligig should be used by industrial concerns and flown by experienced helicopter pilots. He also feels it can be useful for rescue work, forest patrol, fire fighting, crop dusting, geological exploration and special military purposes. Such a trial period would reveal actual cost figures on operation and maintenance, the life expectancy of the machine, and would provide fair production to reduce initial cost. Later, more general commercial use might

prove it practical for taxi service, executive travel and private ownership.

Stanley Hiller, the California boy aeronautical genius and onetime associate of Henry Kaiser in helicopter building, believes the privately-owned helicopter will be practical in the near future. His factory is an armory in the center of Berkeley, with a 50×75 foot lot as a take-off site. To avoid breaking regulations governing flight over restricted areas, the Hiller machines must climb 1,500 feet vertically before moving forward. Hiller, incidentally, has placed two counter-rotating rotors on his machine, thus eliminating the little tail propeller and removing the danger of spinning.

At this writing, no helicopter has received its Approved Type Certificate from the CAA, though many manufacturers have applied. In addition, 101 domestic and eight foreign helicopter route applications have been filed with the Civil Aeronautics Board.

Among the manufacturing applicants are Bell, Sikorsky, Higgins, PV Engineering Forum and Kellett. After producing 400 military helicopters, Sikorsky has decided on the S-51, a four-passenger development of the Army’s R-5, which will do 100 m.p.h. on 450 h.p. The PV Engineering Forum

will manufacture its PV-3 transport. Kellett reports that their earliest commercial production will be on transport type helicopters, but did not announce details. Higgins has nothing to say.

Bell, most willing to talk and definitely an outfit to watch closely, has already spent 1,400,000

dollars of its own money on a helicopter program.

In addition to the planned production of 500 two-seaters, it is known that Bell has a five passenger or cargo helicopter in the 500 h.p. class. Larry Bell, whose company made the Airacobra, Kingcobra and Airacomet, summed up the situation in a recent interview:

“The helicopter has been both, oversold and undersold. We are

going to pick our customers carefully for the first helicopters we sell. We believe that government agencies and commercial and industrial organizations will be our first customers, and that because of their needs it will be many years before the private individual

who wants a helicopter merely for sport or recreation will be able to obtain this type of aircraft.” Mr. Bell emphasized that the helicopter is a very safe machine but pointed out that development of the machine is in its infancy and that he thought it should be recognized that there might be acci-

dents and fatalities just as there are in fixed wing aircraft and even automobiles.

“We are not looking for the man-in-the-street trade at present and probably won’t be for a long time. The first machines are bound to be expensive and even when production goes up to several thousand a year, helicopters will probably cost between three and five thousand dollars. There has been talk of a

fifteen hundred dollar helicopter for family use, but I’m glad somebody else said it and not I.”

A more pungent Bell remark is, “Man wants to fly like a bird and not like a bat out of hell. The helicopter is the nearest approach to bird flight.” fit

Continued from page 59

Source Article