Naval officers—whether or not they themselves wear wings—must likewise keep a sharp lookout not to be caught AOL in this bewildering parade of progress. Naval aviation of 1950 is not the naval aviation of 1945—or for that matter, of 1949. The progress rate is self-compounding, with yesterday’s new knowledge being today’s booster charge for a larger detonation tomorrow.
It is appropriate, therefore, that naval officers analyze the past twelve months, and see how quickly the scenes are changing. The technical improvements, the operational milestones, the new equipment on board and on deck must inevitably be reflected across the entire Navy—from textbooks to tactics.
The propeller is a good example. After the recent war, the prop seemed destined for the junk-heap along with fabric covered wings and isinglass windscreens. Most aeronautical engineers thought that if that invisible, seemingly invincible sonic barrier was to be penetrated, only a jet engine could do it. They were quick to draw an efficiency curve to prove that above 500 miles per hour, the propeller was as useless as a baseball bat.
Yet, in mid 1950, the Navy is actively sponsoring propellers—supersonic propellers. In fact, in 1945 when other aviation interests were abandoning the propeller-type engine for the jet-type engine, the Navy made this announcement: “The propeller-type gas turbine promises to be probably a more useful all-around power plant than the simple turbo-jet, at least for the majority of navy aircraft applications.” The Navy remembered one basic fact that a lot of engineers had forgotten—that a propeller blade was also an airfoil—and if an airfoil could be made to fly through and on the supersonic side of the wall, so could a propeller—and, the Navy thought, with more economy. BuAer experts estimated that a properly designed propeller with only 55% efficiency could grind itself though the wall.
Fiscal 1950 also saw the announcement of the compound aircraft engine—a combination of reciprocating and turbine types. The Navy’s announcement did not make a spectacular news splash, but nonetheless it was an important development. First of all, the Wright Turbo-Cyclone engine was the first compound engine ever to pass the rigid military tests; it was more powerful (up to 20%), it was more economical (also 20%), and it was lighter. Had the Navy’s “Truculent Turtle” been equipped with these improved engines, its world record long distance flight in 1947 might have been boosted from 11,236 miles to 13,483 miles.
The Navy became interested in the idea of a combination engine in mid-1946. Naval air experts thought that some way could be found to extract energy from the hot exhaust gases. The 1950 result is the compound engine. The eighteen cylinders exhaust into three 10 ½-inch turbines, and the additional power is geared back to the crankshaft. These engines are now installed in two naval patrol planes, the P2V4 Neptune, and the P5M Mercator.
Perhaps the outstanding technical advancement for naval aviation in the past twelve months is the appearance of the turbo-prop engine, now powering two current aircraft, the A2D “Skyshark,” and the XP5Y “Convair” patrol boat. Not to be confused with the compound engine described above, the turbo-prop is a gas turbine engine driving a conventional propeller. Pound for pound, this engine is less than half the weight of the conventional reciprocating engine, yet is appreciably more powerful. (The modern radial gasoline engine weighs 1.1 pounds per horsepower. The engine in the P5Y develops 5500 H.P., yet weighs only 2,500 pounds.) Most of the power is generated by the turbine blades driving the propeller, though some thrust is obtained from escaping gases from the tailpipe.
It should be recorded that the Navy first became interested in the turbo-prop in 1939 and was the sponsor which continually encouraged and contracted for its development.
What do such technical developments mean to Naval Aviation? Obviously, the combination of the supersonic propeller and the gas turbine engine is of major importance. It is a well-known fact that jet engines are fuel gluttons, consuming up to ten times as much fuel as the piston-type engine. As a consequence, they are not only expensive to operate, but must carry so much gasoline that either their range or their payload must suffer. For the present, at least, the only practical solution for their voracious appetites is to carry more fuel.
A gas turbine, however, driving a supersonic propeller, would lick the thorny fuel-range problem without sacrificing power, speed, altitude, or rate of climb. A plane equipped with a supersonic prop and a turbo-prop engine would truly be versatile—it could take off handily, whereas, a jet cannot; it could fly economically at slow speeds, whereas a jet cannot; it could fly economically at low altitudes, whereas a jet cannot; and the combination of light initial weight, plus the weight-saving of extra gasoline which is not carried, would produce an aircraft whose payload is far superior to the straight jet for the same expenditure of fuel. For example, the weight of the A2D “Skyshark” is only a small percentage of any other tactical support aircraft with a similar payload capacity. The A2D can climb to altitudes of most jets, tote a heftier load, and carry it farther. In summary, the turbo-engine and the supersonic prop promise the performance of jet propulsion with the economy and payload of conventional piston aircraft.
It is appropriate to point out that Aviation Week, the aeronautical voice of the industry, has reported that by 1954 the United States Air Force plans to equip two groups of B-36 bombers with turbo-prop engines.
Another notable advancement is in the helicopter, the post-War development of which has been little short of phenomenal. First flown by Mr. Sikorsky in 1941, this versatile machine made an immediate impression on naval airmen. Adopted into the fleet in 1943, the experts have since been rushing its further development.
It has advanced far enough in seven years to have replaced scout planes on battleships and cruisers; and no carrier operates today with a helicopter suspended nearby to rescue unfortunate aviators. It is only a question of time until the plane-guard destroyers are returned to their post in the picket line.
Ideal for utility work of all kinds—from carrying mail, passengers and ice cream, to plane guarding, calibrating radar, spotting, and rescue duty—the helicopter is now destined for even more important naval duties.
On June 13, 1950, the Navy made a brief but far-reaching announcement about the helicopter: “The Bell Aircraft Corporation has won the Navy-sponsored competition for the design of an anti-submarine helicopter. The winning design is for a helicopter that will weigh 13,000 pounds and be powered with a single Pratt and Whitney R-2800 engine. A contract is now being negotiated with the Bell Corporation for three experimental models of the ASW helicopter.”
The Navy has added no details to this announcement, but to any military man, the potential role of the helicopter in anti-submarine warfare is obvious. The helicopter can hover and look; it can fly slowly and track; it can fly relatively fast and search. It can carry a respectable load of search equipment and armament. A difficult target for a sub, it is dependable, easy to build, and relatively cheap.
Another technical development sponsored by the Bureau of Aeronautics in the last twelve months and which holds great promise for the future is a new titanium alloy. The alloy embodies five per cent chromium and three per cent aluminum. This alloy has the advantage of being as strong as high-strength steel with only one-half its weight. Moreover, titanium is a non-critical metal which is abundantly available on the North American continent. It is therefore expected that its use in engines will make possible greater engine powers and significant airframe weight savings, resulting in greater range, payload, and maneuverability characteristics.
Fiscal Fifty also saw an air-ordnance development of great significance—the “Mighty Mouse” rocket for air-to-air targets. This explosive projectile can destroy the largest bomber flying today with a single hit. Our BuOrd experts referred to it as “a powerful addition to the weapons of interception fighter aircraft.” It has a greater range and muzzle velocity than the 20 mm. aircraft gun, the explosive charge is larger, (the rocket’s diameter is three inches) yet it may be carried in quantity by a small tactical aircraft. The “Mouse” has folding fins which extended after launching to give directional stability.
The successful testing of this missile is important because it gives us a weapon which is as modern as our aircraft. After all, our fighters and interceptors, just as our combat ships, are primarily gunnery platforms. Against near-sonic speed bombers, our World War II armament was rapidly becoming old fashioned. The new rockets were designed for specific use against modern, high-speed aircraft.
In the operational field, fiscal 1950 has also been a banner year for naval aviation. The operation of jet aircraft aboard carriers is so routine that it is now a normal procedure for both Sixth and Seventh Fleet carriers to include in their complement at least one jet squadron. After the war, a few false prophets were questioning the efficacy of jets from carriers. The assimilation of the jets is now complete, with the successful completion in March of 1950 of night carrier jet landings.
The Second Fleet in the fall of 1949 successfully operated carrier planes at the Arctic Circle, the ships penetrating the turbulent and icy Davis Straits several miles north of the Arctic Circle.
Large land-type patrol planes, fully loaded have taken off this year from our carriers. On February 8, 1950, a combat loaded P2V took off from the carrier, Franklin D. Roosevelt, off Jacksonville, Florida. Flying via the southern route, it crossed the United States and Central America to Panama, then north over San Diego and to San Francisco to land. The total journey was 5,156 miles. And in May, 1950, the Navy announced that carrier landings by the P2V would be completed this summer or fall.
In April, 1950, the Navy’s big new flying boat, the P5Y, passed its initial flight test in San Diego Bay. This flight was of more than usual significance. In fact, some aeronautical optimists predicted that this particular seaplane would mark a turning point for all waterborne aircraft. The XP5Y-1 weighs 60 tons and has a range exceeding 3,000 miles. But the Navy’s announcement that its speed is in “excess” of 350 miles an hour re-opens the age-old landplane-versus-waterplane battle.
Every combat airplane is a compromise—or many compromises. In the middle thirties, the overseas commercial airlines, after trying both land and seaplanes, decided upon the land type. This decision favored the land plane’s speed over the seaplane’s range, a disparity which the former has since continued to enjoy. Seaplanes could always be built with tremendous range and capacity—witness the record of Martin Mars in flying the Pacific—but to combine these qualities with speed has been an engineering enigma.
Thus, the Navy’s announcement of a 60-ton flying boat with a 3,000-mile range whose speed exceeds 350 miles per hour is of more than passing interest. It represents an “uncompromised” airplane, one which can apply its own advantages in competition against the landplane.
This summary should indicate that naval aviation is not standing still, nor will it soon disappear from the scene. This fact is highlighted by the recent statement of the Chief of Naval Operations to the First Class Midshipmen of the Naval Academy:
“It is my earnest conviction that the future of Naval Aviation has never been so challenging, so vital, and so bright.”
Graduating from the Naval Academy in 1941, Commander Cagle saw two years’ destroyer service in the North Atlantic before taking flight training. After commanding Fighting Squadron 88 on the carrier Yorktown in the Pacific War, he served on the staff of Commander Air Force, Atlantic Fleet, for two years. Recently in command of a VF squadron on the U.S.S. Franklin D. Roosevelt, he is now stationed in Washington and engaged as a co-author of the “Battle Report” series.