Rare Bird: The Curtiss A-18

Curtiss A-18

Beautiful but not deadly - The Curtiss A-18 Shrike

The Curtiss A-18 Shrike: Another Step on the Curtiss Treadmill to Oblivion

In 1934 the Curtiss Aeroplane and Motor Company realized at long last that it had barking up the wrong design tree with its modern looking but very heavy all-metal attack planes. Deciding to make a clean start, it made an offer that Donavan R. Berlin could not refuse, hiring him to become Curtiss’ Chief Engineer with the mission of making the company dominant again in the production of fighters and attack planes.

Berlin, whose motto was “design for producibility” (sic), had just finished a five year stint as Chief Engineer at the Northrop Corporation. There, working closely with Jack Northrop, he had pioneered metal construction on the Alpha, Beta and Gamma models, as well as contributing to the design of the nifty looking if ultimately unsuccessful fighters such as XFT-1.

By the fall of 1935, he probably felt very pleased with himself, for he saw the first flights of the prototypes of two entirely new airplanes, both incorporating the lessons he learned at Northrop. The first of these was the Curtiss Model 75, which evolved into the P-36 and then later into the P-40. The second was the Curtiss Model 76, a clean, twin-engine cantilever wing monoplane. It looked like a world beater but was not to find similar success.

Both planes appeared at a time when the aviation corporations of the world were beginning to shake off the crippling malaise of the Great Depression. They began to produce aircraft that incorporated modern all-metal construction, enclosed cockpits, retractable landing gear, flaps and other keys to more speed, range and altitude. The years 1935 and 1936 were particularly fruitful for fighters, with the prototypes of five important aircraft making their first flights, including the Messerschmitt Bf 109, Hawker Hurricane, Supermarine Spitfire, Curtiss Model 75 and Mitsubishi A5M all taking to the air.
The technological advancements had spurred interest in new classes of aircraft. These were larger, twin engine types intended for use in the attack role, for reconnaissance—and if you were really optimistic, as long range escort fighters. The most successful of these was the German Messerschmitt Bf 110, which made its first flight in May, 1936. It was to have an inglorious career in the escort role, but a glorious one as a night fighter. In France the sleek looking Potez 63 debuted in April, 1936 and was eagerly embraced by the Armée de l’Air. It was built in large numbers for the time, but proved to be too vulnerable for intensive combat use.

Berlin’s Model 76 was the American counterpart to these foreign advances, and was undoubtedly the most aesthetically attractive Curtiss airplanes since the P-6E. While less successful than either the Bf 110 or Potez 63, it affected the development direction of American twin-engine light bombers to a significant degree.

The failure of the design was not entirely its own fault, for there were problems concealed within the Curtiss organization that only grew more apparent with the passage of time, and which even a genius like Berlin could not overcome.

Growing Old in Corporate America
Given that corporations are managed by human beings, it is no surprise that corporations have some human characteristics, among them the results of age.

There are vivid illustrations of this in the United States today where the automobile makers which dominated the 20th century may now be heading toward bankruptcy, with hard charging companies from Japan and Korea nipping at their heels. The giant American firms became so large, so laden with bureaucratic procedures and so certain that their position in the industry could not be challenged that they fell behind. Where once they were world leaders, innovative, and the symbols of quality, the aging process slowed them down. Their products became less competitive, they lost sight of the desires of the consumer, and they focused on other aspects of their business instead of focusing on building great cars. As a result their market share has declined, and unless they are able to make huge changes, they will go the way of Nash, Packard, Studebaker and other once familiar names.

Exactly the same sort of aging process happened to the Curtiss-Wright Corporation, formed in 1929 with the combination of the two great rival firms, the Curtiss Aeroplane and Motor Company and the Wright Aeronautical Corporation. In 1929 neither company was strongly associated with the surviving namesakes, Glenn Curtiss and Orville Wright.

Of the two firms, Curtiss had the greatest aircraft heritage, for Wright Aeronautical was known primarily for its fine radial engines. The Curtiss aircraft line went back to 1907, and included such stellar products as the Curtiss JN-4 trainer, exciting planes such as the Pulitzer and Schneider Cup racers, and the long line of beautiful biplane pursuits.

The Curtiss firm had a penchant for meeting demands for new aircraft from the U.S. Army and Navy by stretching existing designs to have a bit more performance. Thus their line of Falcon biplanes went from the original XO-1 of 1924 all the way through 1932, when ten O-1Es were built under license in Chile. The Falcon line embraced both observation and attack aircraft, and served both the Army and the Navy in that role.

The conservatism of the Curtiss design philosophy stemmed from two sources. One was the limited military budgets of the time, which could not afford costly experimentation in advanced types. The other was the inherent business philosophy of the Curtiss management which was headed by Clement Melville Keys, a Canadian born investment banker who became president of Curtiss Aeroplane and Motor Company in 1920 and subsequently guided the firm’s policy of expansion by acquisition.

Initially Keys was the right man at the right time, for he brought the company from near-bankruptcy to a dominant position in American aviation. At one point, Keys personally headed no less than 26 corporations, including aviation holding companies that included North American Aviation and National Aviation Corporation, as well as Transcontinental Air Service.

By 1929, Keys’ new Curtiss Wright Corporation consisted of the original Curtiss Aeroplane and Motor Company; The Curtiss-Caproni Corporation; The Curtiss-Robertson Airplane Manufacturing Company; The Keystone Aircraft Corporation; The Moth Aircraft Corporation; the Travel Air Manufacturing Company; The Wright Aeronautical Corporation; The Curtiss-Wright Flying Service’ the Curtiss-Wright Sales Corporation; and the Curtiss-Wright Export Corporation. Even for so eminent an executive as Keys, this was too much to manage in a coherent manner. Many of the companies competed for the same market, and there was a marked lack of research effort among them. As a result, the stock market crash of 1929 had devastating results on the company, which was saved from extinction only by a timely order from Columbia, which bought 26 Hawk fighters and 100 Falcon observation planes in the early 1930s.

Keys departed the company in 1932, pleading illness, but still managing to keep his hand in other aviation enterprises for many years. He left Curtiss with a series of plants to shut down and an ailing product line that cried for rejuvenation. The firm lived for years on its Hawks and Falcons, which were typical of the period, fixed gear, open cockpit biplanes of mixed construction. It had a strong hold on the observation and attack market that the Falcon served, although Douglas observation planes provided strong competition, just as Boeing had with their fighters.

Curtiss A-18The company’s experiments with all-metal construction began in 1930, with the delivery of the Curtiss XF9C-1 Sparrowhawk to the Navy. Intended to be carried by the huge Akron and Macon dirigibles, the Sparrowhawk performed well enough in a role that was destined to die out with the sequential crashes of the two dirigibles.

The next Curtiss all-metal effort was the Stuka-like Model 59, which was developed successively into the A-8, A-10 and A-12 Shrike. All-metal, with trailing edge flaps and full span leading edge slats, the awkward looking Shrikes also featured enclosed cockpits and a well faired if bulky undercarriage. Modernity did not extend to a cantilever wing, however, and the Shrikes were festooned with both struts and wires. They were also heavy, with an empty weight for the production A-12 of 3,898 pounds, compared to 2,902 pounds for the A-3 Falcon. At a maximum speed of 176 mph, they were forty miles an hour faster than the Falcon, carried 100 pounds more bombs, but had 150 miles less range.

The next disappointment was the Curtiss XP-31, which looked like a miniature Shrike, with its strut braced wings, spatted landing gear and enclosed cockpit. Like the Shrikes, it too was heavy, and it lost out to the lighter, faster, Boeing P-26 in 1932.

The company survived for a while on pedestrian scout-planes for the navy, handsome enough in their way, but demonstrably obsolete with their biplane wings and fabric covering. Built in both float and landplane versions, these SOC-series Seagulls kept the wolf from the door while Berlin worked to make Curtis prosperous once again.

The Model 76 made its first flight in September 1935 as a company-owned aircraft. It was tested at Wright Field, Ohio, and then returned to Curtiss for modifications before being accepted as the XA-14. Powered by two Wright R-1670 engines of 775 horsepower, the XA-14 had a top speed of 243 mph—considerably faster than Boeing’s P-26 fighter, only 30-mph slower than the Model 75 single-seater.

The XA-14 was beautiful compared to the Shrikes which preceded it, and packed four .30-inch machine guns in the nose, with a similar flexible gun in the rather distant rear cockpit. Later in its short, 178 hour flying career, the XA-14 conducted secret tests with a 37-mm cannon installed. The aircraft was quite maneuverable, and could carry twenty 30-pound bombs in the internal bomb-bay.

The Army was impressed enough to buy thirteen service test Y1A-18s at the staggering cost of $104,640 each. The number made procurement officers’ eyes wince, as the last batch of A-12 Shrikes had been purchased for $19,483 apiece. The question arose: were the A-18s five times as good as the A-12?
The A-18s were much improved over the prototype, being equipped with Pratt & Whitney R-1820 engines of 850 horsepower and three-blade Curtiss electric constant speed full feathering propellers—a great advance for the time. Curtiss exerted much effort to reduce drag, fairing in the landing gear doors, but still allowing the wheels to peak through in anticipation of a wheels-up landing. The aircraft was stiletto clean–in company brochures its frontal appearance was likened to “three beads on a string.” Fully loaded, it could sustain a 185-mph cruise speed with one engine shut down.

The installation of full military equipment brought the empty weight up almost 1,000 pounds, and the maximum speed fell off to 239 mph. After a short testing period, the A-18s were sent to the 3rd Attack Group, 8th Attack Squadron at Barksdale Army Air Field, Louisiana.

The 8th quickly proved the effectiveness of the A-18 in exercises, and was awarded the coveted Harmon Trophy for gunnery and bombing accuracy during its first year of operation.
Unfortunately, the neatly designed retractable landing gear of the A-18 had an inherent weakness, and no less than eight of the thirteen A-18s having their gear collapse on landing or roll-out.

It is always fun to “what if” designs and one might wonder what might have happened if Berlin had been allowed to substituted Alison engines on the A-18 as he had done on the P-36. If he had, the resulting aircraft might have allowed Curtiss to compete with the Douglas A-20 for orders.

The true value of the A-18 was the fact that a large, twin engine aircraft weight six tons could be effective in attack operations, clearing the way for the Army to specify requirements which led to the A-20 and A-26.

6 responses to “Rare Bird: The Curtiss A-18

  1. Interesting info on the A-18. Would like to learn more, especially it’s limited use by the 13th squadron.

    • There is not a lot published on the airplane’s activity, which was highlighted by its participation,in full camouflage in the wargames of the period. It was built in too small numbers, and used for too short a period of time, to make much history. It would have been interesting to have seen it developed, with Allison engines, perhaps, and most probably, a different airfoil.
      Best regards


  2. Greetings, and if you see this note I hope you can give it some thought. I have long noticed the stunning visual similarity between the A-18 and the Kawasaki Ki-45 “Nick.” Although the Nick was about 20% smaller, but substantially more powerful (and heavier) it did have some of the combat utility that the A-18 apparently lacked. Was there perhaps some design inspiration for the Nick in the A-18, or was it just another case of synchronicity?

    • Dave, I have noticed the same thing in the past, and while I never made a detailed analysis, I came away with the impression that someone in the Kawasaki engineering had fallen in love with the A-18 as a youth and carried it over to the Ki-45. I doubt if there was any engineering detail involved–the A-18 was dated but the planform is so similar that there had to be a connection.
      All the best

  3. Hello,
    I came across your site from the link in Wikipedia on the Curtiss A-18.
    I have an almost identical photograph of the A-18 with my father, then Lt Robert C. Paul, as pilot. The plane he was flying was AC 16. He was the Armament and Operations officer for the 8th Attack Squadron, 3 Attack Group at Barksdale field from October 1935 to November 1939. He went on to command the 86th Bombardment Group with the A-36 Apaches in North Africa and Sicily in WWII and retired in 1960.

    • Thanks, Mr. Paul, and a long salute to your father–what a career! It was a beautiful airplane, and I always wondered what potential it might have had with bigger engines, etc. Alas–it came at the wrong time in the procurement cycle, I guess.
      All the best


Leave a Reply to Walter Boyne Cancel reply