The sun shone brightly in the Panama sky as the fighter planes from the aircraft carrier Saratoga (CV-3) roared aloft as part of fleet exercises off the coast of the Central American nation. A few days earlier these same planes had launched a surprise “attack” against the Panama Canal that foreshadowed the independent operations of carrier task forces during World War II. On this day, they were part of a mock fleet engagement, with fighter planes escorting bombing and torpedo aircraft. “Climbed so high we near froze to death [and] cruised over to the enemy [battle] line where we discovered all the Lexington planes below us,” wrote Lieutenant Austin K. Doyle of Fighting Squadron (VF) 2B. With the benefits of altitude and surprise, ideal for fighter pilots ready to do battle, Doyle and his division dove into the “enemy” planes, twisting and turning in dogfights. “When we broke off we rendezvoused . . . [and] strafed every ship in the fleet. . . . No other plane came near us.”
The events of a February day in 1929 described above occurred in the midst of a watershed era in naval aviation, the interwar years bringing a host of momentous advancements on multiple levels. From a technological and operational standpoint, none were as important as the aircraft carrier and the tactical and strategic implications of this new weapon of war. Arguably, the key element of the carrier’s success was its main battery in the form of the aircraft that launched from its decks, the unparalleled progress made in the design and operation of carrier aircraft providing the foundation for the flattop’s success during World War II. Similar progress marked other areas of naval aviation as well. Such was the lasting influence of interwar aircraft development that Lieutenant Doyle, who as a Naval Academy plebe during 1916–1917 served in a Navy with just fifty-eight aircraft of assorted types, could in 1929 write of a carrier strike against the Panama Canal and, later in his career as a carrier skipper, order planes designed on drawing boards of the 1930s to attack Japanese-held beachheads and strike enemy ships over the horizon.
On the day World War I ended, the U.S. Navy’s inventory totaled 2,337 aircraft, including heavier-than-air and lighter-than-air types. While this is an impressive total, given the aforementioned aircraft total of fifty-eight when America entered World War I, the number is deceiving. It is true that flying boats built by the Curtiss Aeroplane and Motor Company operated extensively from overseas coastal bases in the antisubmarine role. Yet, when it came to combat types flown at the front, the majority of naval aviators who deployed overseas trained and logged their operational missions in the cockpits of foreign-built airplanes. As the U.S. Navy developed its plan for aircraft production, the realization of the superiority of foreign designs was apparent to, among others, Commander John H. Towers, the Navy’s third aviator, who before U.S. entry into the war had observed firsthand operations of British aircraft during a stint in England as assistant naval attaché. Even after the signing of the Armistice, foreign types retained their importance to the U.S. Navy’s operations. With overseas observers having witnessed the launching of wheeled aircraft from flight decks built on board British ships, aircraft like Sopwith Camels, Hanriot HD-1s, and Nieuport 29s were procured for use in Navy experiments flying landplanes from temporary wooden platforms erected atop the turrets of fleet battleships. Ironically, the performance of these aircraft, built in the factories of England and France, proved a key factor in the shaping of the interwar aircraft building program.
Indeed, if there was one driving force behind the development of aircraft for the U.S. Navy during the 1920s and 1930s, it was the realization of the importance of shipboard aircraft to naval aviation operations. While this had been on the minds of naval aviation personnel from the beginning—among the earliest experiments conducted were the testing of catapults for launching aircraft from ships—most naval aviators were initially wedded to seaplanes. Upon arriving in Pensacola, Florida, to establish the Navy’s first aeronautical station there in January 1914, Lieutenant Commander Henry Mustin wrote to his wife of the difficulties of finding a suitable site for an airfield from which to operated landplanes and dirigibles: “Personally, I don’t approve of the Naval flying corps going in for those two branches because I think they both belong to the Army.” This philosophy would guide aircraft operations during naval aviation’s first decade and beyond, with naval aviator training and operations centered on seaplane operations.
British experience in World War I, namely the operation of wheeled-aircraft from ships, coupled with the aforementioned experiments on U.S. Navy battleships carried out during winter maneuvers at Guantanamo Bay, Cuba, in 1919, prompted a shift in thinking. Weighed down by pontoons, floatplanes simply could not compare with landplanes when it came to speed and maneuverability. Also, ships operating floatplanes, while they could launch them relatively quickly, had to disrupt operations to come alongside a returning aircraft and crane it back aboard. The aircraft carrier, with a deck devoted to the launching and recovery of aircraft, offered the most promise of maximizing the potential of aircraft in fleet operations.
By 1927, three aircraft carriers—Langley (CV-1), Lexington (CV-2), and Saratoga (CV-3)—had been placed in commission, their presence giving naval aviation heretofore unrealized capabilities in fleet operations and a potential as offensive weapons at sea or against land targets. “The value of aircraft acting on the defensive as a protective group against enemy aircraft is doubtful unless it is in connection with an offensive move,” wrote naval aviator Commander Patrick N. L. Bellinger in his Naval War College thesis in 1925.
The most effective defensive against air attack is offensive action against the source, that is enemy vessels carrying aircraft and therefore, enemy aircraft carriers, or their bases and hangars on shore as well as the factories in which they are built. The air force that first strikes its enemy a serious blow will reap a tremendous initial advantage. The opposing force cannot hope to surely prevent such a blow by the mere placing of aircraft in certain protective screens or by patrolling certain areas. There is no certainty, even with preponderance in numbers, of making contact with enemy aircraft, before they have reached the proper area and delivered their attack, and there is no certainty even if contact is made, of being able to stop them.
Nine years later, the Navy’s war instructions for 1934 emphasized the importance of seizing the offensive during a fleet engagement. “If the enemy aircraft carriers have not been located, our fleet is in danger of an air attack. In this situation, enemy carriers should be located and destroyed,” the document read. It further stated that if enemy carriers had been located, either with their aircraft on board or their strike groups having been launched, U.S. carrier planes would “vigorously” attack them, “destroy[ing] their flying decks.”
This realization of the threat of enemy air power in a fleet action stimulated tactical thought, which in turn influenced the design of the planes tasked with delivering the blows against enemy carriers. Initially, it was conventional wisdom that torpedoes would be the most effective method of attack against enemy ships, but whether an aerial torpedo or a bomb, the struggle facing aircraft designers was developing aircraft that could carry the weight of the ordnance without compromising too much in the way of speed, maneuverability, and range. The first successful torpedo plane design introduced into fleet service was Douglas Aircraft Company’s DT, which was important in more than one respect. First, it was the maiden military plane produced by the company, symbolizing the emergence of a postwar aircraft manufacturing base marked by the opening of such companies as Douglas and Grumman Aircraft Engineering Corporation. These firms, founded after World War I, joined such wartime entities as the Curtiss Aeroplane and Motor Company, Boeing Company, Glenn L. Martin Company, and the Naval Aircraft Factory—the latter a Navy-owned center for manufacturing and testing of airplanes—in meeting the demands of the Navy’s aircraft programs. Second, due to the weight of aerial torpedoes, while earlier torpedo plane designs were twin-engine ones that were unsuitable for carrier use, the single-engine DT was capable of shipboard operations and of carrying a payload of 1,835 pounds. In fact, on 2 May 1924, a DT-2 version of the design carrying a dummy torpedo successfully catapult launched from Langley anchored at Naval Air Station (NAS) Pensacola, Florida. Finally, the DT pointed to the future in its composition, the traditional wood and fabric used in aircraft, while still present, accompanied by sections of welded steel.
Following the DT into production was Martin’s T3M/T4M torpedo planes (versions were also built by Great Lakes with the designation TG), which boasted a higher speed than the DT and could carry versions of the Mk-VII torpedo that was in the Navy’s weapons arsenal during the late 1920s. Its introduction coincided with the first significant involvement of aircraft carriers in fleet exercises, which revealed much about the employment of torpedo planes. Fleet pilots all too quickly found that the operational parameters of their torpedoes left much to be desired, any hope of a successful attack necessitating that the weapon be dropped at an altitude of no more than twenty-five feet with the aircraft flying at a maximum speed of eighty-six miles per hour. Malfunctioning torpedoes were the norm rather than the exception, and the survivability of torpedo planes flying “low and slow” was questionable. Noted a section of the Aircraft Squadrons, Battle Fleet document “Aircraft Tactics—Development of” dated 3 February 1927: “Even with anti-aircraft gunfire in its present underdeveloped stage, torpedo planes cannot hope to successfully launch [an] attack from 2,000 yards and less.” By 1930, there were serious questions as to the wisdom of operating torpedo planes at all.
The introduction of the Mark XIII torpedo held enough promise for the continuation of the torpedo mission, the weapon capable of being launched at a range of 6,300 yards from altitudes of between 40 and 90 feet and at a speed of 115 mph. The weapon’s weight of 1,927 pounds mandated the introduction of a more capable torpedo plane, the Navy selecting another Douglas design, the TBD Devastator. First flown in 1935, the TBD was cutting edge for its era given the fact that it was a monoplane of all-metal construction with a top speed of over 200 mph. It would be upon the wings of the TBD that torpedo squadrons went to war in 1941 and 1942.
Developing alongside airborne torpedo attack as an element of naval aviation’s offensive arsenal was aerial bombing. Before World War I and in the years immediately following, battleship officers remained skeptical of the ability of an aircraft to sink a capital ship with bombs. Though bombing tests conducted by Army and Navy airplanes against antiquated U.S. ships and captured German vessels during 1921 proved a success in the damage they inflicted, the fact that the target ships were at anchor with no anti-aircraft defenses left many Navy officers skeptical. Yet, as the first decade of the 1920s progressed, bombing offered increasing promise. “The relative merits of the torpedo plane and the bombing plane has [sic] been a much mooted question recently,” Chief of the Bureau of Aeronautics Rear Admiral William A. Moffett told an audience at the Army War College in 1925. “Potentially, the aircraft bomb is, I believe, the most serious menace which the surface craft has to face at the present time.” The following year, operations in the fleet focused on a particular type of bombing attack that offered the best chance to make Moffett’s potential menace a real one. On an October day off the coast of San Pedro, California, sailors on the decks of the battleships of the Pacific Fleet heard the whine of aircraft engines and spotted dark specks diving toward them. What they saw and heard were F6C Hawks of Fighting VF Squadron 2 making a simulated attack, the pilots positioning their planes in steep dives as they roared down on their targets. The event marked the first fleet demonstration of the tactic of dive-bombing, and less than two months later squadrons of Aircraft Squadrons, Battle Fleet completed their first dive-bombing exercise.
As was the case with the development of torpedo aircraft, the evolution of bomber designs during the interwar years was in part driven by the increasing weight of the ordnance, their reason for being. Yet, most of the aircraft initially filling the “light bombing” role were not employed solely in that mission, the Bureau of Aeronautics as late as 1927 issuing the opinion that there was no need for a specialized aircraft for that task alone. Four years later the air groups in Lexington and Saratoga did not even include a bombing squadron, each carrier instead embarking two fighting squadrons with one devoted to the fighting mission and one to light bombing. Even the aircraft considered the first Navy design built specifically for dive-bombing, the Curtiss F8C, was a dual mission aircraft that operated in the fleet as a fighter bomber.
During the prewar years the fleet would never divest itself of using a multi-mission aircraft as a dive-bomber, but during the early 1930s the Bureau of Aeronautics issued requests for proposal for a new classification of aircraft called the scout-bomber to equip carrier-based scouting and bombing squadrons. This aircraft would fulfill the missions outlined in the war instructions of attacking enemy surface ships and scouting tactically. Among naval aircraft, the scout-bombers designed in the decade preceding World War II were among the most technologically advanced. The SBU was the first capable of exceeding 200 mph, its wings reinforced to handle the stress of steep dives carrying a 500-pound bomb, while the BF2C-1 Goshawk possessed an all-metal wing structure that made it even more durable in a dive. The SB2U Vindicator, ordered in 1934, was the sea service’s first monoplane scout-bomber. However, the greatest developments came with the Northrop BT-1 and the SBD Dauntless. The former, delivered in 1937, incorporated unique split flaps, the upper and lower flaps opening when the airplane was in a dive. When flight tests revealed extreme buffeting in the horizontal stabilizer, engineers added holes to the flaps, which remedied the problem and in dive-bombing runs slowed the aircraft and made it a stable bombing platform. This technology carried over to Douglas Aircraft Company’s SBD Dauntless, which boasted a top speed of 256 mph, could carry a 1,000-pound bomb, and had a maximum range of 1,370 miles in the scouting configuration. Enhancing the capabilities of these aircraft as dive-bombers was equipment such as telescopic sights and a bomb crutch, the ladder swinging ordnance away from the fuselage during a dive so that falling bombs did not strike the aircraft’s propeller.
In comparison to dive-bombers and torpedo planes, fighter aircraft had a sound foundation upon which to build during the interwar years, air-to-air combat having advanced more during World War I than other arenas of air warfare. Fighters provided cover for bases and ships against enemy air attack and protected bombing and torpedo planes en route to bomb enemy targets, their missions also including clearing the skies of enemy fighters and shooting down enemy scouting planes to deny information to enemy commanders. In short, on the wings of fighter planes rested the responsibility of gaining control of the air and maintaining air superiority, the ideal characteristics for aircraft tasked with this mission being speed, rate of climb, and maneuverability. These characteristics were greatly enhanced in naval aircraft by the introduction of air-cooled engines, embodied by the Pratt & Whitney Wasp. Unencumbered by a radiator that was standard on water-cooled engines, the Wasp was lighter, the savings in weight translating into improved performance. Endurance tests also revealed that air-cooled engines were more reliable, which was appealing for naval aircraft that operated over open ocean far removed from land bases.
As mentioned above, Navy fighters of the interwar era were viewed as multi-mission platforms, as evidenced by the fact that it was fighters that delivered the first successful fleet demonstration of a dive-bombing attack. The Bureau of Aeronautics, in issuing specifications to aircraft companies for the design of new fighter planes, routinely included parameters for the aircraft in the bombing role. As tactics developed during the 1920s and 1930s, however, air-minded officers came to the realization that saddling fighters with a bomb diminished their ability to provide air superiority. As Rear Admiral Harry E. Yarnell commented in 1932 during his tour as Commander, Aircraft Squadrons, Battle Force, “It is becoming increasingly evident that if the performance of fighters is to be improved . . . bombing characteristics of fighters must be made secondary to fighting characteristics.”
Yarnell’s letter coincided with the emergence of the first fighter designed by the relatively new Grumman Aircraft Engineering Corporation, the FF-1. Delivered in 1933, the airplane boasted features new to Navy fighters, including an enclosed cockpit canopy, an all-metal fuselage, and retractable landing gear. Though its forward fuselage was bulbous in order to house the latter, the FF-1 had a top speed of 207 mph, this attribute becoming readily apparent to a U.S. Army Air Service squadron commander, who upon seeing one of the “Fifis” during a tactical exercise over Hawaii in 1933 decided to make a run on it. “Great was his amazement when his dive upon the innocent looking target failed to close the range.” One other aspect of the FF-1’s design was that it was a two-seater, with room for a pilot and observer, an arrangement more in line with torpedo and bombing planes. This fact sparked a debate among fighter pilots over the direction of design of future aircraft. In a 1935 memorandum to the Chief of the Bureau of Aeronautics, the commanding officer of VF-5B noted the two-seat fighter’s superiority in escorting strike groups was possible because of the observer’s ability to scan the skies for enemy aircraft and proclaimed it less vulnerable to diving attack by enemy fighters for the same reason. The VF-5B skipper argued that the two-seater was equal to or superior to the single-seater in all tactical missions required of fighter aircraft. Conceding the general advantage of smaller, single-seat fighters in speed and maneuverability, he concluded that in naval warfare control of the air was obtained not by air-to-air superiority over enemy aircraft formations, but by knocking out the carriers from which the enemy planes operated. “In this the superior characteristic of the single-seater fighter can play little or no part.”
A tactical board convened by Commander, Aircraft Squadrons, Battle Force issued a report on the issue the following January, defining a fighter plane as a “high speed weapon of destruction against other aircraft.” The board criticized the dismissal of this fundamental mission of Navy carrier fighters, writing that the VF-5B commander’s report “gives undue importance to secondary fields of employment . . . emphasizing the suitability of the airplane for a function which is not one for which a VF [fighter plane] is properly suited.” The board concluded that “present VF aircraft in service are of practically no value as VF. They lack either necessary speed superiority over other types or necessary offensive armament, or both.”
This quest for speed would endure, with Grumman following up the FF-1 with first the F2F and then the F3F biplanes, each faster but limited in capability when compared with the Japanese A6M Zero also under development in the late 1930s (the A6M-2, which was operational in 1940, had a top speed of 331 mph compared to 264 mph for the F3F-3). Throughout the late 1930s the Bureau of Aeronautics initiated requests for proposals to the nation’s aircraft industry for fighter designs that emphasized speed and improved armament. In this approach of casting a wide net, the Navy received a variety of designs. Some, including the unorthodox twin-engine F5F Skyrocket, did not enter production, while others, namely Brewster’s F2A Buffalo monoplane, were put into production, but proved disappointing. The aircraft that emerged as the best that could be placed in production most quickly was Grumman’s F4F Wildcat, a monoplane successor to the company’s earlier biplane fighter designs, which with its super-charged engine achieved a maximum speed of 333.5 mph at an altitude of 21,300 feet and boasted four .50-caliber machine guns for armament. On it would rest the fortunes of Navy and Marine fighter squadrons until 1943.
The aircraft carrier and the airplanes that flew from her deck represented the cutting edge of naval aviation operations of the interwar years, with New York Times reporter Lewis R. Freeman capturing the public’s excitement over the ship’s unique operations in an article written in the aftermath of Fleet Problem IX. “Just about the most spectacular show in the world today . . . is the handling and manoevering [sic] of the great carriers Lexington and Saratoga,” he wrote. “The spectacle of launching and landing planes is fully up to the superlative scale of the ship itself. . . . In the darkness of early morning the effect is heightened by circles of spitting fire from the exhausts and the colored lights of the wings and tail.” However, the foundation upon which the airplane entered naval service was seaplanes and flying boats, and in the immediate postwar years they provided naval aviation’s first real integration with fleet operations.
Established in early 1919, Fleet Air Detachment, Atlantic Fleet, put to sea in exercises with surface forces, part of its operations being flights of wheeled aircraft from improvised decks on board battleships. However, significant attention was also devoted to flying boat operations and their support of surface ships, particularly in the spotting of naval gunfire. “For the first time in the history of the Navy, the actual setting of the sights was, to a large extent, controlled by the officers of the Airboat squadron,” read an air detachment report of 1920. “This marks the beginning of a new era in our naval gunnery.” Success in this role, the spotting of naval gunfire, led to the eventual assignment of detachments of seaplanes to cruisers and battleships as part of cruiser scouting (VCS) and observation (VO) squadrons, respectively. To fill this requirement, a number of aircraft procured by the Navy during the interwar years, including the VE-7, UO/FU, and O2U, could be operated in both the landplane and floatplane configuration. By the time the United States entered World War II, the principal aircraft flying in the scouting and observation roles were the Curtiss SOC Seagull and Vought OS2U Kingfisher, the latter a monoplane of which over a thousand were eventually produced.
Long-range scouting would become the domain of flying boats, the detachment demonstrating their endurance in a lengthy seven-month cruise with the fleet, logging 12,731 nautical miles, some 4,000 of which were in direct maneuvers with the fleet. Meanwhile, in the Pacific, flying boats and seaplane tenders formed Air Force, Pacific Fleet in July 1920, putting to sea for joint fleet exercises that demonstrated the scouting capabilities of Navy flying boats. During the cruise, wartime F-5L flying boats covered a distance of 6,076 miles in operations between California and Central America. Wrote Admiral Hugh Rodman, Commander in Chief, Pacific Fleet, at the conclusion of the exercises, “The scouting work performed by the seaplanes was carried out to a distance of about one hundred and sixty-five miles from the bases and in weather which, except under war conditions, might have caused the commander of the force to hesitate about sending the planes into the air.”