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Curtiss XP-934: A Bold Experiment

Curtiss XP-934: A Bold Experiment

 The 1932 XP-934 is based on the Curtiss XP-31 Swift, the airplane maker’s first monoplane fighter

A vintage black and white photo of a 1932 Curtiss XP-934 fighter aircraft

The 1932 Curtiss XP-934 was a bold but failed experiment in aircraft design. Despite its problems, the plane’s engineering helped pave the way for future fighter designs. (Photo from the Paul S. Maynard archive)

BY MARK MAYNARD

The Curtiss XP-934 Swift was a bold but failed experiment in World War II aircraft design. Built in 1932, the XP-934 is based on the Curtiss XP-31 Swift, the airplane maker’s first monoplane fighter.

In 1932, the world is still reeling from the Great Depression, but aviation is booming. New aircraft designs are always emerging, and the Army Air Corps is eager to stay ahead of the curve. To seek innovation in aircraft design and manufacturing, the United States Army Air Corps held several competitions in the 1930s to develop new aircraft for the service. In addition to the competitions, the Army Air Corps also worked directly with aircraft manufacturers to develop new aircraft.

The newly formed Curtiss-Wright Corp. was among the makers to join the competition in 1932. The mission was to create an experimental pursuit-attack aircraft.

Pursuit aircraft became vital for their nimbleness for such duty missions as dive-bombing troops on the ground, escorting bombers to their targets in enemy territory, taking reconnaissance imagery, and clearing the airspace of opposing aircraft.

The Curtiss-Wright entry, designated XP-934 by the Army, is the first enclosed cockpit fighter aircraft for the USAAC. It was also one of the last pursuit aircraft with fixed landing gear and externally braced wings.

Why the XP-934 Failed

For the USAAC competition, Curtiss proposed a radical design that featured a low-wing monoplane configuration with a retractable landing gear. The XP-934 was powered by a 700-horsepower Wright XR-1510 Cyclone radial engine, giving the plane a top speed of more than 200 mph.

After the Curtiss XP-934’s first flight on July 25, 1932, however, it was immediately apparent that the aircraft was underpowered and overweight. The single-seat fighter weighed around 850 pounds and carried 125 gallons of fuel, four .30 caliber machine guns, and ammunition. The retractable landing gear also proved to be problematic, and it was eventually removed.

However, according to a report on Aviatar.org, the sole airframe was re-engined with a 447kW Curtiss V-1570 Conqueror V-12 powerplant. In 1933 flight tests, the V-12 offered no improvement.

The Curtiss XP-934 is never ordered into production. Despite its problems, however, the XP-934 was a significant aircraft in aviation history. It was the first enclosed cockpit fighter aircraft for the USAAC, and it helped to pave the way for future fighter designs.

Curtiss XP-934 Specifications

Crew: 1

Length: 23 feet 9 inches

Wingspan: 35 feet 3 inches

Height: 8 feet 10 inches

Wing area: 226 square feet

Empty weight: 3,334 pounds

Gross weight: 4,143 pounds

Powerplant: 1 700 hp Wright XR-1510 Cyclone 9-cylinder radial engine

Performance

Maximum speed: 215 mph

Initial climb rate: 2,130 feet per minute

Service ceiling: 22,700 feet

Range: 396 miles

Armament

4 .30 caliber machine guns

Source: Wikipedia

Note: This is another image from my dad, Paul Smith Maynard, who worked four decades in aviation as an engineer. Dad began his career in about 1943 after graduating from West Virginia University. He started with Curtiss-Wright Corp., a pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International.

See more of his vintage plane pics here.

1930 Curtiss-Wright Kingbird Model 55

1930 Curtiss-Wright Kingbird Model 55

Though praised for its handling and performance, the 7-passenger Curtiss-Wright Kingbird airliner was not a commercial success and was pulled from production in 1934

A black and white image of a 1930 Curtiss Wright KIngbird

The 1930 Curtiss Kingbird Model 55 was powered by two Wright J-6-9 Whirlwind nine-cylinder air-cooled radial piston engines, each producing 300 horsepower. (Photo from the Paul S. Maynard archive)

BY MARK MAYNARD

The Curtiss-Wright Kingbird was a short-lived U.S. airliner built in small numbers in the early 1930s. The twin-engine Kingbird was a well-liked aircraft by its operators and was praised for its good handling and performance. However, it was not a commercial success and was withdrawn from production in 1934. The Kingbird was replaced by the Curtiss-Wright Condor, a larger and more powerful airliner.

According to the plane’s page in Wikipedia,  the Kingbird was a twin-engine evolution of the single-engine Curtiss Thrush. It shared a similar fuselage but with two engine nacelles mounted on the struts on either side of the fuselage. The Kingbird had a blunt nose behind the propeller arcs, allowing the engines to be mounted closer together. The engines were positioned closer to the plane’s centerline to minimize asymmetrical thrust in the event of engine failure.

The Kingbird was powered by two Wright J-6-9 Whirlwind nine-cylinder air-cooled radial piston engines, each producing 300 horsepower. It had a maximum speed of 175 miles per hour and a range of 600 miles. The Kingbird could carry a crew of one and seven passengers.

The Kingbird was first flown in 1930 and was certified by the U.S. Department of Commerce in 1931. Curtiss-Wright built a total of 25 Kingbirds between 1931 and 1934. The airliner was used by a number of airlines, including Eastern Air Lines, Transcontinental Air Transport, and Western Air Express.

Curtiss Kingbird Factoids

  • The Kingbird was named after the Eastern Kingbird, a small bird known for its aggressive behavior;
  • The Curtiss Kingbird was the first airliner equipped with a radio altimeter;
  • The U.S. Army Air Corps used the Kingbird as a training aircraft.

Curtiss-Wright Kingbird Specifications

Crew: 1

Capacity: 7 passengers

Length: 34 feet, 5.125 inches

Wingspan: 54 feet, 6 inches

Height: 10 feet, 0 inches

Wing area: 405 square feet

Empty weight: 3,877 pounds

Gross weight: 6,115 pounds

Powerplant: 2 × Wright J-6-9 Whirlwind 9-cylinder air-cooled radial piston engines, 300 horsepower each

Maximum speed: 175 miles per hour

Range: 600 miles

NOTE: This is another image from my dad, Paul Smith Maynard, who worked four decades in aviation as an engineer. Dad began his career in about 1943 after graduating from West Virginia University. He started with Curtiss-Wright Corp., a pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International. See more of his vintage plane pics here.

1945 Curtiss SB2C Helldiver

1945 Curtiss SB2C Helldiver

The Curtiss SB2C Helldiver had nicknames of “Son of a Bitch Second Class,” the “Beast,” and worse by many a pilot

A black and white image of a 1945 Curtiss Helldiver shot from below while the plane was in flight.

By the end of the Pacific theater during World War II, the Curtiss SB2C Helldiver had become the main dive bomber and attack aircraft on USN carriers. But problems with its development delayed its introduction and saddled it with a bad reputation. (Photo from the Paul S. Maynard archive)

BY MARK MAYNARD

The Curtiss SB2C Helldiver sent Japanese warships to the bottom of the ocean. It pulverized fortifications on Japan’s home islands. And the Helldiver left a trail of wreckage in its wake, yet, it was a less-than-stellar performer built by an aircraft company in decline.

According to a report by Robert F. Dorr in WarfareHistoryNetwork.com, its design was a recipe for trouble.

It was a round, blue tube squatting on a tiny tailwheel carrying a pilot and radioman-gunner in tandem behind a 1,900-horsepower Wright R-2600 radial engine, he wrote.

With a wingspan of 49 feet, 9 inches, the Curtiss SB2C Helldiver had nicknames of “Son of a Bitch Second Class,” the “Beast,” and worse by many a pilot, Dorr wrote. However, “the plane was neither as bad as its critics said nor as good as its manufacturer hoped.”

Bad Reputation

“The Helldiver’s career began with problems. The prototype XSB2C-1 made its maiden flight on December 18, 1940, but it was destroyed just days later.

Curtiss rebuilt the aircraft and flew it again in October 1941, but it crashed a second time after a month. After production moved to Columbus, Ohio, from Buffalo, New York, the first production Helldiver flew in June 1942.”

The Columbus plant would go on to build more than 5,000 Helldivers. Only a few survivors exist. In the Battle of the Philippine Sea, 45 Helldivers, most of which had been launched from extreme range, were lost when they ran out of fuel while returning to their carriers, according to the Helldiver’s Wikipedia page

Stability and Structural Issues

From the start, the blue warplane garnered a reputation for poor stability, structural flaws, and poor handling, wrote Dorr in WarfareHistoryNetwork.com.

“Britain rejected the Helldiver after receiving 26 examples. Lengthening the fuselage by one foot and redesigning the fin fixed the aerodynamic problems.

“The stability and structural issues were exaggerated — yet more than one Helldiver broke in half when making a hard tailhook landing on a wooden carrier deck.

“The Helldiver offered an internal bomb bay that could accommodate a 1,000-pound bomb and be closed by hydraulically operated doors,” wrote Dorr. “Hardpoints under the wings accommodated additional ordnance.”

“Perhaps the most important change came with an improved propeller. After a 12-foot Curtiss Electric three-blade prop proved inadequate, a four-blade propeller from the same manufacturer with the same diameter and with root cuffs was introduced with the SB2C-3 model.”

By this time, Curtiss had smoothed out nearly all imperfections in the design, Dorr wrote. The next-generation SB2C-4 followed, introducing “cheese grate” upper and lower wing flaps perforated like a sieve; they enhanced stability.

By the war’s end, technological advancements allowed other aircraft to deliver an equal or greater bombload with comparable accuracy, eliminating the need for a specialized dive bomber. Thus, the SB2C Helldiver was the last dive bomber in the Navy’s inventory.

Curtiss SB2C Helldiver Specifications

Crew: 2

Length: 36 feet 8 inches

Wing span: 49 feet 9 inches

Wing area: 422 square feet

Empty weight: 10,547 pounds

Number built: 7,140

Gross weight: 16,616 pounds

PERFORMANCE

Powerplant: 1 × Wright R-2600-20 Twin Cyclone 14-cylinder air-cooled radial piston engine, 1,900 hp

Propellers: 1 4-blade constant-speed prop

Maximum speed: 295 mph at 16,700 feet

Cruise speed: 158 mph

Combat range: 1,165 miles with 1,000-pound bombload

Service ceiling: 29,100 feet

Rate of climb: 1,800 feet per minute

ARMAMENT

Guns: 2 × 20mm (0.787 inch) AN/M2 cannon in the wings; 2 × 0.30 inch (7.6mm) M1919 Browning machine guns in the rear cockpit; 4 X 0.50 inch (13mm) M2 Browning machine guns, two each in gunpods mounted on underwing hardpoints

Rockets: 8 5-inch high-velocity aircraft rockets

Bombs:  2,000 pounds in the internal bay, or 1 Mark 13-2 torpedo on underwing hardpoints: 500 pounds of bombs each

*Specs from Wikipedia

NOTE: This is another image from my dad, Paul Smith Maynard, who worked four decades in aviation as an engineer. Dad began his career in about 1943 after graduating from West Virginia University. He started with Curtiss-Wright Corp., an early pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International.

Curtiss P-40 Warhawk

Curtiss P-40 Warhawk

The 1944 Curtiss P-40 was conceived as a pursuit aircraft and was agile at low and medium altitudes but suffered from a lack of power at higher altitudes

A 1944 Curtiss P-40 Warhawk fighter plane

The most famous Curtiss P-40 Warhawk unit was undoubtedly the American Volunteer Group, better known as the ‘Flying Tigers,’ who had great success flying the plane in China and Burma in early 1942. (Photo from the Paul S. Maynard archive)

BY MARK MAYNARD

The single-seat Curtiss P-40 Warhawk was obsolete when it was drafted for service at the start of World War II. But it was the best fighter that the United States had available in large numbers, according to a report at the Museum of Flight. Despite continued improvements, the P-40 never equaled the capabilities of its German or Japanese adversaries. But it had one priceless advantage, “It was available and being efficiently mass-produced when needed most.”

The solid and reliable Warhawk was an effective weapon when its strengths were leveraged: diving passes and rapid departure without engaging in a turning dogfight with more agile opponents.

According to Airplane-Online.com, the P-40 was a descendant of the “Hawk” line produced by the Curtiss-Wright Aircraft Corp. in the 1930s and 1940s. It shared certain design elements with its predecessors, the Hawk and Sparrowhawk.

The all-metal fighter was first flown in 1938, and the P-40 was kept in production until 1944. The P-40 was the third most-produced American fighter, after the P-51 Mustang and P-47 Thunderbolt.

Warhawk in Wartime

With its six .50-caliber Browning machine guns and a 700-pound bombload (one 500-pound and two 100-pound bombs), the P-40 served in all theaters of operation. The U.S., Britain, Canada, Australia, New Zealand, Free French, South Africa, and Russia flew the Curtiss fighter.

“The British called it the Tomahawk (B and C models) and Kittyhawk (D and E models). The F through R versions were known as Warhawks in U.S. service. The N model had decreased fuel capacity and increased armor, along with other minor system changes, relative to its predecessors.

“The most famous P-40 unit was undoubtedly the American Volunteer Group, better known as the ‘Flying Tigers.’ Painted with a shark-mouth face, the P40 had great success flying the plane in China and Burma in early 1942.

In the hands of a skilled pilot, the P-40 could exceed its limitations and out-maneuver and out-fight anything in the sky, Flying Tiger ace David L. “Tex” Hill said in 2005 interview for DefenseMediaNetwork.com.

“It was sturdy and handled well, except in a spin, but you never piloted a P-40 without wishing you had something a little better,” Hill said.

P-40 at Pearl Harbor

P-40s engaged Japanese aircraft at Pearl Harbor and in the Philippines in December 1941. They also served in North Africa in 1943 with the 99th Fighter Squadron, the first African American U.S. fighter unit.

Though often slower and less maneuverable than its adversaries, the P-40 Warhawk earned a reputation in battle for extreme ruggedness. It served throughout the war but was eclipsed by more capable aircraft.

More than 13,738 P-40 fighters were built from 1939-1944 at the Curtiss plant in Buffalo, Ny.

NOTE: This is another image from my dad, Paul Smith Maynard, who worked four decades in aviation as an engineer. Dad began his career in about 1943 after graduating from West Virginia University. He started with the Curtiss-Wright Corp., an early pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International.

See more of his vintage plane pics here.

1922 U.S. Army Curtiss Racer

1922 U.S. Army Curtiss Racer

Curtiss Aeroplane produced several outstanding racing aircraft during the 1920s, flown by Navy and Army pilots, the latter including First Lt. “Jimmy” Doolittle

 

A black and white photo of a 1922 Curtiss biplane racer

The Army Curtiss Racer in final motor testing, Sept. 16, 1922, at Mitchell Field, in Garden City, N.Y. Lt. Alford J. Williams, U.S.M. (at the tail) and W.L. Gilmore, chief engineer for the Curtiss Co. at the Curtiss Aeroplane development and testing facility. (Photo from the Paul S. Maynard archive)

 

BY MARK MAYNARD

Just as automobile racing was gaining traction in the years before World War I (1914-18), so was airplane racing. The most famous of these aerial speed contests in the United States and Europe was the international competition known as the Schneider Cup Races.

According to an online report by the U.S. Naval Institute, Jacques Schneider, a wealthy French aero enthusiast, originated the races as a stimulus for seaplane design and the development of overwater flying. The competitions were administered by the Fédération Aéronautique Internationale and offered a trophy valued at some $5,000.

The races were for seaplanes and had to be flown entirely over water for a minimum distance of 150 nautical miles. Competitors raced against the clock — not each other — with the fastest average time winning. And the races had to be international.

The first Schneider race was held in 1913, with the United States represented by a privateer. The races were suspended during World War I, then resumed in 1919.

Subsequently, the U.S. military entered the Schneider races three times. The U.S. Navy-Curtiss racers twice won first and second places.

The Pulitzer Trophy Race 

In 1921, the Navy decided to compete in the Pulitzer Trophy Race, which the Army had won the previous year. Curtiss was the only major U.S. aircraft firm with prior experience in racer design, and on June 16, 1921, the Navy awarded the firm a contract for two aircraft, though some sources say three planes were built. The Navy had no effective designation scheme, so the aircraft were designated Curtiss Racer (CR) No. 1 and CR No. 2 (which was retained in naval service).

Designed by Mike Thurston and Henry Routh and built at Garden City, Long Island, New York, these were streamlined biplanes with a single, open cockpit. A variety of drag-reducing features were incorporated. Both CRs had wheeled undercarriages, but there were slight differences between the two aircraft.

Their 425-horsepower V-12 Curtiss engines ran on a 50/50 mixture of benzol and gasoline. The water-cooled D-12 had a displacement of 18.8 liters.

 Daring Lt. “Jimmy” Doolittle

According to a news story at Airminded.net, the first of the three Curtiss racers (including R3C) was put through its preliminary trials during the week of Sept. 19, 1922.

Alford J. Williams, U.S.M., was to pilot the Navy entry in the Pulitzer Race and Lieut. James H. Doolittle, Army Air Service, flew the plane for short trials to determine airworthiness.

On Sept. 18, Lt. Doolittle, for the first time, opened the throttle wide and flew the actual course of the Pulitzer Race from Mitchel Field, where these tests were carried out. W.L. Gilmore, chief engineer for the Curtiss Company, timed the trials and reported an average speed of 254 mph. for two circuits of the course.

The testing exceeded by approximately 11 mph the last Pulitzer speed figure set up when the Navy Curtiss racer won this race at St. Louis in 1923, clocking 243.6 mph.

The testing at Curtiss’ Garden City plant was considered in every way to be a great achievement in racing airplane design.

The Army went on to win the 1922 Pulitzer race with the new Curtiss R-6 racer, which led the Navy to order two similar aircraft in 1923. Designated R2C-1, these “logical” evolutions of the CRs and R-6s included improved engines that were boosted to 507 horsepower.

On Oct. 6 that year, Navy pilots captured first and second place in the Pulitzer race with speeds of 243.68 mph and 241.77 mph, respectively. Both speeds were later exceeded by those aircraft. In 1923, after the race, one of the R2C-1s was “sold” to the Army for $1 (becoming the Army’s R-8).

Curtiss Aeroplane Legacy

Curtiss produced several outstanding racing aircraft during the 1920s, flown by Navy and Army pilots, the latter including First Lt. “Jimmy” Doolittle.

According to Marine Lieutenant Colonel Robert Rankin of the naval institute:

“Although this country participated officially in the Schneider event for only three years, it did gain considerable technical data from the contests. In addition to the goodwill engendered by the Navy pilots, the races were of positive value in drawing the attention of the general public to our naval air program in the period following World War I when it was all too fashionable to criticize the services. More important, of course, were the research aspects of the contests, the results of which led to many important aircraft improvements and developments.”

NOTE: This is another image from my dad, Paul Smith Maynard, who worked four decades in aviation as an engineer. Dad began his career in about 1943 after graduating from West Virginia University. He started with Curtiss-Wright Corp., an early pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International.

See more of his vintage plane pics here.

Curtiss Condor Bomber and Civilian Condor

Curtiss Condor Bomber and Civilian Condor
A 1929 black and white photo of a Curtis Condor bomber

This original photo of the Curtiss Condor B-2 bomber was taken at the Curtiss Aerospace development plant in Garden City, N.Y. The image is dated Aug. 14, 1929. (Photo from the Paul S. Maynard archive)

The Curtiss Condor B-2 bomber became known as a ‘Flying Battleship’

BY MARK MAYNARD

Long before the current-generation B2 Spirit “Stealth Bomber” by Northrop Grumman there was the Curtiss Condor B-2 bomber built for the U.S. Army.

It was an enormous fabric-covered biplane aircraft with a wingspan of 90 feet and a length of 47 feet 4 inches. With its armaments, it became known as a “Flying Battleship,” but its use was short-lived.

According to its page in Wikipedia, the B-2 Condor’s two engines sat in nacelles between the wings, flanking the fuselage. It had a twin set of rudders on a twin tail, a configuration that was becoming obsolete by that time. At the rear of each nacelle was a gunner position. And there was another gunner in the nose.

As a twin-engine heavy bomber, the B-2 Condor was powered by two 650-horsepower Curtiss GV-1570-7 Conqueror V-12 water-cooled piston engines.

In a report by Joe Baugher (Encyclopedia of American Aircraft), the engines were housed inside nacelles mounted on top of the lower wing. “The engines were cooled by rather angular radiators that jutted up vertically from each nacelle.

“One of the more unusual innovations introduced by the [second prototype] XB-2 was the addition of a defensive gunner position in the rear of each nacelle. It was hoped that this arrangement would offer a clearer field of fire for the gunners than the more conventional fuselage-situated positions. An additional gunner position was provided in the nose. Each position was provided with a pair of Lewis .30-06 machine guns.”

According to the Baugher report, the Condor’s bombload was typically 2,508 pounds but could be increased to 4,000 pounds on short flights.

Curtiss Condor Competitors

The Curtiss Condor B-2 competed against the Keystone XB-1B, the Keystone XLB-6, the Sikorsky S-37B, and the Atlantic-Fokker XLB-2, according to the Baugher report.

“When an Army board of review met in February of 1928 to decide which design was to be awarded a contract, they immediately ruled out the XB-1B, the XLB-2, and the S-37. However, the board was unable to decide between the XB-2 and the XLB-6. The XB-2 had the better performance, but the XLB-6 was only $24,750 per unit.

“The per-unit cost of the B-2 was $76,373, more than three times the cost of a Keystone bomber. In a split decision, the Board opted for the Keystone design, but on June 23, 1928, Curtiss was given a contract for two B-2s (Serial nos. 28-398/399). A further 10 were ordered in 1929 (29-28/37).

“The twelve production B-2s were delivered from May 1929 to January 1930. Notable differences from the XB-2 included the use of three-bladed propellers and somewhat shorter and wider radiators mounted on top of the engine nacelles.

At sea level, the Curtiss Condor had a maximum speed of 132 mph — though many reports say it struggled to reach that max V — and 128 mph at 5,000 feet. The plane had a cruising speed of 105.5 mph and a cruising range of 805 miles.

End of the Condor Line

During the early 1930s, the advances in bomber design were so rapid that canvas-covered biplanes such as the B-2 rapidly became obsolete, Baugher wrote.

“Consequently, the B-2 served only briefly with the Army, being taken out of service in 1934. The last B-2 was surveyed in July of 1936. So far as I am aware, none survives today.”

After production of the B-2, Curtiss Aircraft left the bomber business, concentrating on the Hawk series of pursuit aircraft in the 1930s.

A 1929 black and white photo of a civilian version of the Curtis Condor bomber

The civilian version of the Curtiss Condor, circa 1944,  was the first airliner in the world to provide sleeping berths. (Photo from the Paul S. Maynard archive)

The Civilian Curtiss Condor

The Model 53 was an airliner version of the Model 52 Condor B-2 bomber. The Condor was the first airliner in the world to provide sleeping berths.

The Army permitted this development in 1928, and the first of the new aircraft made its maiden flight in June 1929. The civilian B-2 was an 18-seat passenger aircraft called the Condor 18 (also known as the Condor T32), according to HistoryOfWar.org.

At the time, there was a need for sleeper-transports, and the simplicity of design allowed for quick production and delivery to serve this market, according to HistoryOfWar. The Curtiss Condor could carry 12 passengers as a sleeper-transport or 15 passengers for day transport.

Luxury Cabin Accommodations

The Condor was the first multi-engine airliner with an electrically operated retractable landing gear. To help absorb vibration, the Condor was the first to have its engines mounted on rubber bushings.

The passenger cabin was appointed in fabric and leather, and each seat had individual hot and cold air vents.

The lavatory featured a basin with hot and cold running water, a mirror, and a vanity. However, the Condor remained in airline service for only three years, making it the last biplane purchased for civil transport.

Only a short time afterward, the all-metal airliners, the Boeing 247 and Douglas DC-1, made their debut in 1933. The only competing factor that the Condor had with the modern airplanes was that it had retractable landing gear.

Two 710 hp Wright SCR-1820-F3 Cyclone, 9-cylinder radial engines powered the passenger Condor.

Condor Flight History

The first civilian Condor converted from a military Model 52, flew for the first time on July 21, 1929. Including the prototype, six were built. Of these, the first three were converted from bomber model 52s. They operated with TAT and Eastern Air Line, though only for about a year. The Conqueror’s development was never quite completed, and in 1932 the US Army, after spending large sums on it, withdrew support and turned to air-cooled engines.

CURTISS B-2 CONDOR SPECIFICATIONS

Twin-engine heavy bomber biplane. Initial production version; 12 built.

Crew: 5; two wing gunners, the nose gunner, pilot, and co-pilot.

Length: 47 feet 4 inches

Wingspan: 90 feet

Empty weight: 9,300 pounds

Gross weight: 16,951 pounds

Powerplant: 2 × Curtiss GV-1570-7 Conqueror V-12 water-cooled piston engine, 600 hp each

PERFORMANCE

Maximum speed: 132 mph

Cruising speed: 105.5 mph

Range: 805 miles

Service ceiling: 17,100 feet

Rate of climb: 850 feet/minute

ARMAMENT

Guns: 6 .30-06 caliber Lewis machine-guns

Bombload: 2,508 pounds

Note: This is another image from my dad, Paul Smith Maynard, who worked four decades in aviation as an engineer. Dad began his career in about 1943 after graduating from West Virginia University. He started with Curtiss-Wright Corp., a pioneer in making flying machines. He went on to work at North American Aviation and Rockwell International.

See more of his vintage plane pics here.