Question Mark (aircraft)
Encyclopedia
The Question Mark was a modified Atlantic-Fokker
C-2A
airplane flown by aviators of the United States Army Air Corps
to experiment with aerial refueling
in 1929. It was used to establish new world records in aviation for sustained flight (heavier-than-air), refueled flight, sustained flight (lighter-than-air), and distance. The records were established between January 1 and January 7.
-built de Havilland
DH-4Bs of the United States Army Air Service
accomplished the feat over San Diego's Rockwell Field
. Subsequently the same group of airmen established an endurance record of remaining aloft for more than 37 hours in August 1923, using nine aerial refuelings. In June 1928, a new endurance record of more than 61 hours was established in Belgium
by Adjutant Louis Crooy and Sgt. Victor Groenen, also using aerial refueling.
2nd Lt. Elwood R. Quesada, an engineer of the U.S. Army Air Corps
stationed at Bolling Field
in Washington, D.C.
, developed a plan with a U.S. Marine Corps aviator from Anacostia Naval Air Station
to break the Belgians' record.According to the January 14, 1929 Time Magazine, in addition to Crooy and Groenen's air-refueled record, an unrefueled endurance record of 65 hours 31 minutes had been set in 1928 by a pair of Germans, Johann Risticz and Wilhelm Zimmerman, but they had not refueled during the flight. The plan was reviewed by Capt. Ira C. Eaker, an aide to Assistant Secretary of War for Air
F. Trubee Davison
. Eaker and Quesada had piloted an aircraft in April 1928 that had nearly crashed from lack of fuel on a long-range rescue mission to Labrador, and had a mutual interest in air-to-air refueling. Eaker took it to Maj. Gen. James E. Fechet, Chief of the United States Army Air Corps
. Both Fechet and Davison approved the project on the condition that it demonstrate a military application and not just as a publicity stunt. Overall command of the project was given to Major Carl A. Spaatz
(who then spelled his named "Spatz"), the Assistant G-3 for Training and Operations in Fechet's office.
at Bolling Field, it was flown to Middletown Air Depot
, Pennsylvania
, for modifications. The C-2A was an American-built military version of the Fokker F.VIIa-3m trimotor, a high-wing monoplane with a gross weight of 10,395 pounds, re-engined with three Wright R-790
motors producing 220 HP (174 kW) each. The C-2A had an internal fuel capacity of 192 gallons in a pair of wing tanks, and for the project two 150 gallons (567.8 l) tanks were installed in the cargo cabin. A hatch was cut in the roof of the C-2 behind the wing for transfer of the fuel hose and passage of supplies from the tanker to the receiver. 72-octane
aviation gasoline would be received in 100 gallons (378.5 l) increments of approximately 90-seconds duration.
A 45 gallons (170.3 l) tank was used to provide engine oil
to the three motors, replenished by inflight deliveries of 5 gallons (18.9 l) cans of Pennzoil
triple-extra-heavy lowered on slings. A copper tubing system was installed in an attempt to adequately lubricate the rocker arm
s of the engines inflight. Doorways were cut on each side of the cockpit and catwalks built on the wings to enable mechanic Roy Hooe to access the engines for emergency maintenance. To reduce propeller
noise, the two wing engines were mounted with Westinghouse twin-blade Micarta
propellers, while the nose engine used a Standard
three-blade steel propeller.
As word of the project spread, its members were continually being asked how long they expected to remain aloft. Their responses were generally to the effect: "That is the question." A large question mark
was painted on each side of the fuselage to provoke interest in the endurance flight, prompting the nickname of the plane.
To deliver the fuel, two Douglas C-1
single-engine transports were also modified, s/n 25-428 designated Refueling Airplane No. 1 and s/n 25-432 as Refueling Airplane No. 2. The biplane
C-1s were evolved from the Douglas World Cruiser
's design, with the pilots side-by-side in an open cockpit forward of the wing. Two 150 gallons (567.8 l) tanks were installed in their cargo compartments, attached to a lead
-weighted 50 feet (15.2 m) length of 2.5 inches (63.5 mm) fire hose
. The nozzle of the hose had a quick-closing valve on the tanker's end and was tightly wrapped with copper wire, one end of which could be attached to a corresponding copper plate mounted in Question Mark to ground the hose. The C-1's would each carry a third crewman in the cargo compartment to reel out the hose or lower a supply rope, and to work the shutoff valve.
football
game played that day in Pasadena
. The refueling planes would be situated at each end of a 110 miles (177 km) long racetrack oval
, one at Rockwell Field
in San Diego and the other at the Metropolitan Airport, now Van Nuys Airport
. The flight would originate and terminate there in order for any endurance record to be officially recognized by the Fédération Aéronautique Internationale
.
Van Nuys was chosen over an existing dirt strip airfield, Mines Field
, located at El Segundo
, because the weather in Van Nuys was considered more reliable, particularly in regard to temperature inversions and smog
. Metropolitan was also an operational facility while Mines Field had just been procured by the City of Los Angeles for use as a commercial airport. The project arrived there in December 1928 to begin preparations for the flight, with Capt. Hugh M. Elmendorf
in charge of logistics and maintenance.
Because of weight considerations and the unreliability of radios, none was installed in the Question Mark. All communications between the aircraft or between Question Mark and the ground had to be accomplished using flags, flares, flashlights, weighted message bags, notes tied to the supply lines, or messages written in chalk on the fuselages of PW-9D
fighters, painted black and nicknamed "blackboard planes". (One such message written on the side of a 95th Pursuit Squadron is externally linked below.)
Harry A. Halverson, 2nd Lt. Quesada, and Sgt.
Roy W. Hooe. Refueling Airplane No. 1 (at Rockwell) was crewed by pilots Capt. Ross G. Hoyt and 1st Lt. Auby C. Strickland, with 2nd Lt. Irwin A. Woodring reeling the hose. Refueling Airplane No. 2 (at Van Nuys) was crewed by pilots 1st Lt. Odas Moon
and 2nd Lt. Joseph G. Hopkins, and hose handler 2nd Lt. Andrew F. Solter.
Four pilots of the 95th Pursuit Squadron
, based at Rockwell Field, flew the PW-9 "blackboard planes": 1st Lt. Archie F. Roth, and 2nd Lts. Homer W. Kiefer, Norman H. Ives, and Roger V. Williams.
, an instrument that continuously recorded altitude and time as documentary evidence for the records.
Less than an hour later Lt. Moon completed the first refueling over Van Nuys. During refuelings, Eaker and Halverson manned the controls, Spaatz and Quesada supervised the fuel exchange, and Hooe operated a "wobble" pump. The C-1 approached the Question Mark from above and behind, maintaining 20 to 30 feet (9.1 m) of vertical separation, until in a position slightly ahead of the C-2. Both aircraft stabilized in level flight at 80 mi/h and the hose was reeled out. Maj. Spaatz climbed on a platform below the open hatch, and wearing rain gear and goggles for protection against fuel spills, grounded the hose and then placed it in a receptacle mounted in the upper fuselage.
Made from a bucket with a sloped floor, the receptacle had connections to the two extra fuel tanks, and at Spaatz's signal Lt. Salter opened the valve. Fuel flowed by gravity into the bucket at 75 gallons (283.9 l) per minute and then into the tanks, where it was then pumped by hand into the wing tanks by Sgt. Hooe. Food, mail, tools, spare parts and other supplies were also passed by rope in the same fashion.
During the first night-time refueling, Spaatz was drenched with fuel when turbulence caused the hose to pull out of the receptacle. Recalling the event in 1975, Eaker said:
Fearing that chemical burns from the gasoline might force him to parachute from the airplane to seek medical treatment, Spaatz ordered Eaker to continue the flight regardless. However Spaatz shed all his clothing and was wiped off with oil-soaked rags. Although he directed at least one refueling without his clothing, replacements were soon delivered. Quesada was briefly overcome by the same accident but quickly revived. Spaatz experienced two other fuel spills without injury, using oil to wipe his skin and zinc oxide
to protect his eyes.
Fog, turbulence, and darkness altered the refueling schedule, shortening some contacts and delaying others. On six occasions the Question mark was forced away from its flight track to refuel, once over Oceanside
and five times over El Centro. Maintaining contact formation became more difficult as the weight of the planes changed during transfer, especially since the refueling pilot could not observe the Question Mark. Capt. Hoyt developed a system whereby Lt. Woodring tugged on a string tied to the pilot's arm if the C-1's speed was excessive. Early in the flight a window blew out of the C-2's cabin, but a replacement was eventually hauled up and installed by Sgt. Hooe.
s by completely opening the throttles.
On the afternoon of January 7, the left wing engine quit. Hooe went out on the catwalk to attempt repairs, immobilizing the windmilling propeller with a rubber hook. Eaker increased throttle on the remaining two engines to maintain flight while repairs were attempted, and they too began to strain. The plane lost altitude from 5,000 to 2550 feet (777.2 m) before Hooe was called back inside and the decision made to land.
The Question Mark landed under power at Metropolitan Airport at 2:06 p.m., 150 hours, 40 minutes, and 14 seconds after takeoff. The left engine had seized because of a pushrod failure, and the others all suffered severe rocker arm
wear.
, resupplied Question Mark 27 times (ten at night), while Lt. Moon's crew at Van Nuys flew 16 sorties, two at night. In all, the flight broke existing world records for sustained flight (heavier-than-air), refueled flight, sustained flight (lighter-than-air), and distance.
All five crew members were decorated with the Distinguished Flying Cross
at a ceremony held at Bolling Field on January 29. The crews of the tankers, on the other hand, went unrecognized. Eventually all six received letters of commendation for their participation, but it was 47 years before their vital role in the operation was recognized with decorations. By then only Hoyt and Hopkins remained living, but both personally received Distinguished Flying Crosses on May 26, 1976.
mail plane nicknamed the Boeing Hornet Shuttle on a transcontinental endurance flight eastbound from Oakland, California
, he was refueled in flight by C-1s and Boeing Model 40 aircraft. Over Cleveland, Ohio
, a Boeing refueling crew accidentally dropped a five-gallon can of oil through his wing, ending the first attempt. On a second attempt westbound, his engine quit over Utah
when dirt clogged the fuel line, forcing him to crashland in the mountains near Salt Lake City.
The flight of the Question Mark inspired a rash of projects to break the endurance record. In 1929 alone 40 flights were attempted, all by civilians, and nine succeeded in surpassing Question Marks record. At the end of 1929 the record stood at over 420 hours, established by Dale "Red" Jackson and Forest E. "Obie" O'Brine in the Curtiss Robin
Greater St. Louis.
The Air Corps followed up the flight of the Question Mark with a mission to demonstrate its applicability in combat. On May 21, 1929, during annual maneuvers, a Keystone LB-7 piloted by Lt. Moon took off from Fairfield Air Depot
in Dayton, Ohio
, on a simulated mission to New York City
via Washington, D.C. Plans were for the bomber to be refueled in flight several times, drop a flash bomb over New York harbor, then return to Dayton non-stop, again by way of Washington. Moon had 1st Lt. John Paul Richter, who had been a hose handler on the first-ever refueling aerial refueling mission on May 28, 1923, as a member of his five-man crew. The C-1 tanker employed to refuel the LB-7 was flown by Capt. Hoyt and two enlisted men. While attempting an air refueling en route from Dayton to Washington, icing forced the tanker to land in Uniontown, Pennsylvania
, where it got stuck in mud. After flying to New York, the LB-7 was forced to land at Bolling Field. The next day the tanker joined the bomber and both flew to New York, where they made a public demonstration of air refueling and four dry runs.
Of the 16 Army aviators involved in the project, six later became general officers. Spaatz, Eaker and Quesada played important roles in the United States Army Air Forces
during World War II
. Spaatz rose to commanding general of the Army Air Forces and became the first Chief of Staff of the United States Air Force
. Eaker commanded the Eighth
and Mediterranean Allied Air Forces. Quesada commanded the IX Tactical Air Command
in France. Strickland, Hoyt and Hopkins all became brigadier generals in the United States Air Force, and the Brigadier General Ross G. Hoyt Award is issued annually for the best air refueling crew in the Air Force. Halverson, though he rose only to colonel, led the HAL-PRO ("Halverson Project") detachment, 12 B-24 Liberator
s that bombed the Ploieşti
oil refineries in 1942, and was the first commander of the Tenth Air Force
.
Moon, a bomber pilot, became an influential member of the "Bomber Mafia
" at the Air Corps Tactical School
from 1933 to 1936, but died on November 19, 1937, awaiting retirement from the service at the age of 45. Solter, a pursuit pilot, was killed in an accident flight-testing an all-metal trainer at Randolph Field
, Texas, in September 1936. Elmendorf, while not having a flying role in the project, was an accomplished test pilot and was killed on January 13, 1933, testing the Y1P-25
at Wright Field
, Ohio.
The Question Mark was re-engined with 300 hp Wright R-975 engines in 1931, and redesignated in the practice of the day as a C-7. It served out its service life as the transport airplane for the 22nd Observation Squadron
at Pope Field, North Carolina
, and was surveyed (scrapped) at Randolph Field in 1934. A major component of the refueling device is in the collections of the Historical Society of Berks County
in Reading, PA.
Atlantic Aircraft
Atlantic Aircraft Corporation, also known as Fokker-America and Atlantic-Fokker, was a US subsidiary of the Dutch Fokker Company, responsible for sales and information about Fokker imports, and eventually constructing various Fokker designs....
C-2A
Fokker F.VII
The Fokker F.VII, also known as the Fokker Trimotor, was an airliner produced in the 1920s by the Dutch aircraft manufacturer Fokker, Fokker's American subsidiary Atlantic Aircraft Corporation, and other companies under licence....
airplane flown by aviators of the United States Army Air Corps
United States Army Air Corps
The United States Army Air Corps was a forerunner of the United States Air Force. Renamed from the Air Service on 2 July 1926, it was part of the United States Army and the predecessor of the United States Army Air Forces , established in 1941...
to experiment with aerial refueling
Aerial refueling
Aerial refueling, also called air refueling, in-flight refueling , air-to-air refueling or tanking, is the process of transferring fuel from one aircraft to another during flight....
in 1929. It was used to establish new world records in aviation for sustained flight (heavier-than-air), refueled flight, sustained flight (lighter-than-air), and distance. The records were established between January 1 and January 7.
Background
The first complete inflight refueling between two aircraftWhile they had passed minor amounts of fuel in practice, the June 27 flight was the first aerial refueling mission, an attempt to set an endurance mark. took place on June 27, 1923, when two BoeingBoeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
-built de Havilland
De Havilland
The de Havilland Aircraft Company was a British aviation manufacturer founded in 1920 when Airco, of which Geoffrey de Havilland had been chief designer, was sold to BSA by the owner George Holt Thomas. De Havilland then set up a company under his name in September of that year at Stag Lane...
DH-4Bs of the United States Army Air Service
United States Army Air Service
The Air Service, United States Army was a forerunner of the United States Air Force during and after World War I. It was established as an independent but temporary wartime branch of the War Department by two executive orders of President Woodrow Wilson: on May 24, 1918, replacing the Aviation...
accomplished the feat over San Diego's Rockwell Field
Rockwell Field
Rockwell Field was an Army air base located in Coronado, California, near San Diego. It shared the area known as North Island with Naval Air Station North Island from 1912 to 1935. Its functions were eventually moved to March Field so that the naval air station could take over the whole area...
. Subsequently the same group of airmen established an endurance record of remaining aloft for more than 37 hours in August 1923, using nine aerial refuelings. In June 1928, a new endurance record of more than 61 hours was established in Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
by Adjutant Louis Crooy and Sgt. Victor Groenen, also using aerial refueling.
2nd Lt. Elwood R. Quesada, an engineer of the U.S. Army Air Corps
United States Army Air Corps
The United States Army Air Corps was a forerunner of the United States Air Force. Renamed from the Air Service on 2 July 1926, it was part of the United States Army and the predecessor of the United States Army Air Forces , established in 1941...
stationed at Bolling Field
Bolling Air Force Base
Joint Base Anacostia-Bolling is a military installation, located in Southeast Washington, D.C., established on 1 October 2010 in accordance with congressional legislation implementing the recommendations of the 2005 Base Realignment and Closure Commission...
in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
, developed a plan with a U.S. Marine Corps aviator from Anacostia Naval Air Station
Naval Support Facility Anacostia
Naval Support Facility Anacostia is a United States Naval Base in Anacostia, Washington, D.C. and is conjoined with Bolling Air Force Base. NSF Anacostia falls under the command of Naval Support Activity Washington.-History:...
to break the Belgians' record.According to the January 14, 1929 Time Magazine, in addition to Crooy and Groenen's air-refueled record, an unrefueled endurance record of 65 hours 31 minutes had been set in 1928 by a pair of Germans, Johann Risticz and Wilhelm Zimmerman, but they had not refueled during the flight. The plan was reviewed by Capt. Ira C. Eaker, an aide to Assistant Secretary of War for Air
United States Department of War
The United States Department of War, also called the War Department , was the United States Cabinet department originally responsible for the operation and maintenance of the United States Army...
F. Trubee Davison
F. Trubee Davison
Frederick Trubee Davison , usually known as F. Trubee Davison, or Trubee Davison, was an American World War I aviator, Assistant US Secretary of War, Director of Personnel for the Central Intelligence Agency, and President of the American Museum of Natural History.Davison was the brother-in-law of...
. Eaker and Quesada had piloted an aircraft in April 1928 that had nearly crashed from lack of fuel on a long-range rescue mission to Labrador, and had a mutual interest in air-to-air refueling. Eaker took it to Maj. Gen. James E. Fechet, Chief of the United States Army Air Corps
United States Army Air Corps
The United States Army Air Corps was a forerunner of the United States Air Force. Renamed from the Air Service on 2 July 1926, it was part of the United States Army and the predecessor of the United States Army Air Forces , established in 1941...
. Both Fechet and Davison approved the project on the condition that it demonstrate a military application and not just as a publicity stunt. Overall command of the project was given to Major Carl A. Spaatz
Carl Spaatz
Carl Andrew "Tooey" Spaatz GBE was an American World War II general and the first Chief of Staff of the United States Air Force. He was of German descent.-Early life:...
(who then spelled his named "Spatz"), the Assistant G-3 for Training and Operations in Fechet's office.
Aircraft modification
A new Atlantic-Fokker C-2A transport, serial number 28-120, was selected for the project. Assigned to the 14th Bombardment Squadron14th Bombardment Squadron
The 14th Bombardment Squadron is an inactive United States Air Force unit. The 14th Bomb Squadron fought in the Battle of the Philippines , much of its aircraft being destroyed in combat against the Japanese...
at Bolling Field, it was flown to Middletown Air Depot
Harrisburg International Airport
-Statistics:-Air cargo:Harrisburg International Airport is well positioned with freight-forwarding capabilities. The airport is located adjacent to I-76 , I-83, and I-81, allowing for fast air-to-ground transfer of goods and commodities...
, Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
, for modifications. The C-2A was an American-built military version of the Fokker F.VIIa-3m trimotor, a high-wing monoplane with a gross weight of 10,395 pounds, re-engined with three Wright R-790
Wright R-790
The Wright R-790 Whirlwind was a series of nine-cylinder air-cooled radial aircraft engines built by Wright Aeronautical Corporation, all of which had a displacement of about 790 in³ and around 200 hp...
motors producing 220 HP (174 kW) each. The C-2A had an internal fuel capacity of 192 gallons in a pair of wing tanks, and for the project two 150 gallons (567.8 l) tanks were installed in the cargo cabin. A hatch was cut in the roof of the C-2 behind the wing for transfer of the fuel hose and passage of supplies from the tanker to the receiver. 72-octane
Octane
Octane is a hydrocarbon and an alkane with the chemical formula C8H18, and the condensed structural formula CH36CH3. Octane has many structural isomers that differ by the amount and location of branching in the carbon chain...
aviation gasoline would be received in 100 gallons (378.5 l) increments of approximately 90-seconds duration.
A 45 gallons (170.3 l) tank was used to provide engine oil
Motor oil
Motor oil or engine oil is an oil used for lubrication of various internal combustion engines. The main function is to lubricate moving parts; it also cleans, inhibits corrosion, improves sealing, and cools the engine by carrying heat away from moving parts.Motor oils are derived from...
to the three motors, replenished by inflight deliveries of 5 gallons (18.9 l) cans of Pennzoil
Pennzoil
Pennzoil is an American oil company founded in Los Angeles, California in 1913. In 1955, it was acquired by Oil City, Pennsylvania company South Penn Oil, a former branch of Standard Oil. In 1963, South Penn Oil merged with Zapata Petroleum; the merged company took the Pennzoil name. During the...
triple-extra-heavy lowered on slings. A copper tubing system was installed in an attempt to adequately lubricate the rocker arm
Rocker arm
Generally referred to within the internal combustion engine of automotive, marine, motorcycle and reciprocating aviation engines, the rocker arm is a reciprocating lever that conveys radial movement from the cam lobe into linear movement at the poppet valve to open it...
s of the engines inflight. Doorways were cut on each side of the cockpit and catwalks built on the wings to enable mechanic Roy Hooe to access the engines for emergency maintenance. To reduce propeller
Propeller (aircraft)
Aircraft propellers or airscrews convert rotary motion from piston engines or turboprops to provide propulsive force. They may be fixed or variable pitch. Early aircraft propellers were carved by hand from solid or laminated wood with later propellers being constructed from metal...
noise, the two wing engines were mounted with Westinghouse twin-blade Micarta
Micarta
Micarta is a trademark of Norplex-Micarta industrial high pressure laminates and refers to a composite of linen, canvas, paper, fiberglass, carbon fiber or other fabric in a thermosetting plastic, originally used in electrical and decorative Koekjes applications. Micarta was developed by George...
propellers, while the nose engine used a Standard
Hamilton Standard
Hamilton Standard, an aircraft propeller parts supplier, was formed in 1929 when United Aircraft and Transport Corporation consolidated Hamilton Aero Manufacturing and Standard Steel Propeller into the Hamilton Standard Propeller Corporation. Other members of the corporation included Boeing,...
three-blade steel propeller.
As word of the project spread, its members were continually being asked how long they expected to remain aloft. Their responses were generally to the effect: "That is the question." A large question mark
Question mark
The question mark , is a punctuation mark that replaces the full stop at the end of an interrogative sentence in English and many other languages. The question mark is not used for indirect questions...
was painted on each side of the fuselage to provoke interest in the endurance flight, prompting the nickname of the plane.
To deliver the fuel, two Douglas C-1
Douglas C-1
-References:NotesBibliography* Forden, Lesley. The Ford Air Tours: 1925-1931. New Brighton Minnesota: Aviation Foundation of America, 2003, First edition 1972. No ISBN....
single-engine transports were also modified, s/n 25-428 designated Refueling Airplane No. 1 and s/n 25-432 as Refueling Airplane No. 2. The biplane
Biplane
A biplane is a fixed-wing aircraft with two superimposed main wings. The Wright brothers' Wright Flyer used a biplane design, as did most aircraft in the early years of aviation. While a biplane wing structure has a structural advantage, it produces more drag than a similar monoplane wing...
C-1s were evolved from the Douglas World Cruiser
Douglas World Cruiser
-References:NotesBibliography* Francillon, René J. McDonnell Douglas Aircraft Since 1920: Volume I. London: Putnam, 1979. ISBN 0-87021-428-4.* Swanborough, F.G. and Peter M. Bowers. United States Military Aircraft since 1909. London: Putnam, 1963....
's design, with the pilots side-by-side in an open cockpit forward of the wing. Two 150 gallons (567.8 l) tanks were installed in their cargo compartments, attached to a lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
-weighted 50 feet (15.2 m) length of 2.5 inches (63.5 mm) fire hose
Fire hose
A fire hose is a high-pressure hose used to carry water or other fire retardant to a fire to extinguish it. Outdoors, it is attached either to a fire engine or a fire hydrant. Indoors, it can be permanently attached to a building's standpipe or plumbing system...
. The nozzle of the hose had a quick-closing valve on the tanker's end and was tightly wrapped with copper wire, one end of which could be attached to a corresponding copper plate mounted in Question Mark to ground the hose. The C-1's would each carry a third crewman in the cargo compartment to reel out the hose or lower a supply rope, and to work the shutoff valve.
Planning
The operation was planned to begin January 1, 1929, at Los Angeles, California, both to take advantage of weather conditions and to generate publicity by overflying the 1929 Rose Bowl1929 Rose Bowl
The 1929 Rose Bowl was a college football bowl game and the 15th annual Rose Bowl Game. The Georgia Tech Yellow Jackets defeated the California Golden Bears by a score of 8-7. The game was notable for a play by California All-American Roy Riegels in which he scooped up a Georgia Tech fumble and ran...
football
American football
American football is a sport played between two teams of eleven with the objective of scoring points by advancing the ball into the opposing team's end zone. Known in the United States simply as football, it may also be referred to informally as gridiron football. The ball can be advanced by...
game played that day in Pasadena
Pasadena, California
Pasadena is a city in Los Angeles County, California, United States. Although famous for hosting the annual Rose Bowl football game and Tournament of Roses Parade, Pasadena is the home to many scientific and cultural institutions, including the California Institute of Technology , the Jet...
. The refueling planes would be situated at each end of a 110 miles (177 km) long racetrack oval
Oval
An oval is any curve resembling an egg or an ellipse, such as a Cassini oval. The term does not have a precise mathematical definition except in one area oval , but it may also refer to:* A sporting arena of oval shape** a cricket field...
, one at Rockwell Field
Rockwell Field
Rockwell Field was an Army air base located in Coronado, California, near San Diego. It shared the area known as North Island with Naval Air Station North Island from 1912 to 1935. Its functions were eventually moved to March Field so that the naval air station could take over the whole area...
in San Diego and the other at the Metropolitan Airport, now Van Nuys Airport
Van Nuys Airport
Van Nuys Airport is a public airport located in Van Nuys in the San Fernando Valley section of the city limits of Los Angeles, California, United States. No major commercial airlines fly into this airport; it is used by private, chartered, and small commercial aircraft...
. The flight would originate and terminate there in order for any endurance record to be officially recognized by the Fédération Aéronautique Internationale
Fédération Aéronautique Internationale
The Fédération Aéronautique Internationale is the world governing body for air sports and aeronautics and astronautics world records. Its head office is in Lausanne, Switzerland. This includes man-carrying aerospace vehicles from balloons to spacecraft, and unmanned aerial vehicles...
.
Van Nuys was chosen over an existing dirt strip airfield, Mines Field
Los Angeles International Airport
Los Angeles International Airport is the primary airport serving the Greater Los Angeles Area, the second-most populated metropolitan area in the United States. It is most often referred to by its IATA airport code LAX, with the letters pronounced individually...
, located at El Segundo
El Segundo, California
El Segundo is a city in Los Angeles County, California, United States. Located on the Santa Monica Bay, it was incorporated on January 18, 1917, and is one of the Beach Cities of Los Angeles County and part of the South Bay Cities Council of Governments...
, because the weather in Van Nuys was considered more reliable, particularly in regard to temperature inversions and smog
Smog
Smog is a type of air pollution; the word "smog" is a portmanteau of smoke and fog. Modern smog is a type of air pollution derived from vehicular emission from internal combustion engines and industrial fumes that react in the atmosphere with sunlight to form secondary pollutants that also combine...
. Metropolitan was also an operational facility while Mines Field had just been procured by the City of Los Angeles for use as a commercial airport. The project arrived there in December 1928 to begin preparations for the flight, with Capt. Hugh M. Elmendorf
Elmendorf Air Force Base
Joint Base Elmendorf-Richardson is a United States military facility adjacent to Anchorage, the largest city in Alaska. It is an amalgamation of the former United States Air Force Elmendorf Air Force Base and the United States Army Fort Richardson, which were merged in 2010.-Overview:The...
in charge of logistics and maintenance.
Because of weight considerations and the unreliability of radios, none was installed in the Question Mark. All communications between the aircraft or between Question Mark and the ground had to be accomplished using flags, flares, flashlights, weighted message bags, notes tied to the supply lines, or messages written in chalk on the fuselages of PW-9D
Boeing Model 15
-Bibliography:*Lloyd S. Jones, U.S. Naval Fighters Fallbrook CA: Aero Publishers, 1977, pp. 35-38. ISBN 0-8168-9254-7.*Swanborough, Gordon and Bowers, Peter M. United States Navy Aircraft since 1911. London: Putnam. Second edition 1976. ISBN 0-370-10054-9....
fighters, painted black and nicknamed "blackboard planes". (One such message written on the side of a 95th Pursuit Squadron is externally linked below.)
Crews
The crew of Question Mark consisted of Maj. Spaatz, Capt. Eaker, 1st Lt.First Lieutenant
First lieutenant is a military rank and, in some forces, an appointment.The rank of lieutenant has different meanings in different military formations , but the majority of cases it is common for it to be sub-divided into a senior and junior rank...
Harry A. Halverson, 2nd Lt. Quesada, and Sgt.
Sergeant
Sergeant is a rank used in some form by most militaries, police forces, and other uniformed organizations around the world. Its origins are the Latin serviens, "one who serves", through the French term Sergent....
Roy W. Hooe. Refueling Airplane No. 1 (at Rockwell) was crewed by pilots Capt. Ross G. Hoyt and 1st Lt. Auby C. Strickland, with 2nd Lt. Irwin A. Woodring reeling the hose. Refueling Airplane No. 2 (at Van Nuys) was crewed by pilots 1st Lt. Odas Moon
Odas Moon
Odas Moon was an American aviation pioneer who was among a team of United States Army Air Corps aviators to break endurance records by performing aerial refueling. Moon was a founding member of the Order of Daedalians...
and 2nd Lt. Joseph G. Hopkins, and hose handler 2nd Lt. Andrew F. Solter.
Four pilots of the 95th Pursuit Squadron
95th Fighter Squadron
The 95th Fighter Squadron was part of the 325th Fighter Wing at Tyndall Air Force Base, Florida. It conducted advanced fighter training for the F-15 Eagle aircraft.-History:...
, based at Rockwell Field, flew the PW-9 "blackboard planes": 1st Lt. Archie F. Roth, and 2nd Lts. Homer W. Kiefer, Norman H. Ives, and Roger V. Williams.
Takeoff and refueling
Question Mark took off from Van Nuys at 7:26 a.m. on New Years Day 1929 with Capt. Eaker at the controls, carrying only 100 gallons (378.5 l) of fuel to save takeoff weight. Aboard the Question Mark, either Halverson or Quesada did most of the piloting during cruising flight while Eaker monitored the throttles for smoothest engine performance. A log was kept by the flight officer (co-pilot) and dropped to the ground daily, and Eaker was responsible for winding the barographBarograph
A barograph is a recording aneroid barometer. It produces a paper or foil chart called a barogram that records the barometric pressure over time....
, an instrument that continuously recorded altitude and time as documentary evidence for the records.
Less than an hour later Lt. Moon completed the first refueling over Van Nuys. During refuelings, Eaker and Halverson manned the controls, Spaatz and Quesada supervised the fuel exchange, and Hooe operated a "wobble" pump. The C-1 approached the Question Mark from above and behind, maintaining 20 to 30 feet (9.1 m) of vertical separation, until in a position slightly ahead of the C-2. Both aircraft stabilized in level flight at 80 mi/h and the hose was reeled out. Maj. Spaatz climbed on a platform below the open hatch, and wearing rain gear and goggles for protection against fuel spills, grounded the hose and then placed it in a receptacle mounted in the upper fuselage.
Made from a bucket with a sloped floor, the receptacle had connections to the two extra fuel tanks, and at Spaatz's signal Lt. Salter opened the valve. Fuel flowed by gravity into the bucket at 75 gallons (283.9 l) per minute and then into the tanks, where it was then pumped by hand into the wing tanks by Sgt. Hooe. Food, mail, tools, spare parts and other supplies were also passed by rope in the same fashion.
Sustaining flight
The five men aboard Question Mark underwent medical examinations before the flight, and their flight surgeon planned a special diet. However an electric stove to heat food was eliminated to save weight, and hot meals were sent aloft by the refuelers, including a turkey dinner on New Years Day prepared by a church in Van Nuys. The crew warded off boredom by reading, playing cards, sleeping in bunks mounted over the fuel tanks, and writing letters.During the first night-time refueling, Spaatz was drenched with fuel when turbulence caused the hose to pull out of the receptacle. Recalling the event in 1975, Eaker said:
We went over the Rose Bowl. It was very bumpy, as you can appreciate, as we should have appreciated, up against those mountains in January, and the refueling plane and the Question Mark were torn apart. I was piloting the Question Mark and I realized that General Spaatz had probably been drenched in high octane gasoline.
Fearing that chemical burns from the gasoline might force him to parachute from the airplane to seek medical treatment, Spaatz ordered Eaker to continue the flight regardless. However Spaatz shed all his clothing and was wiped off with oil-soaked rags. Although he directed at least one refueling without his clothing, replacements were soon delivered. Quesada was briefly overcome by the same accident but quickly revived. Spaatz experienced two other fuel spills without injury, using oil to wipe his skin and zinc oxide
Zinc oxide
Zinc oxide is an inorganic compound with the formula ZnO. It is a white powder that is insoluble in water. The powder is widely used as an additive into numerous materials and products including plastics, ceramics, glass, cement, rubber , lubricants, paints, ointments, adhesives, sealants,...
to protect his eyes.
Fog, turbulence, and darkness altered the refueling schedule, shortening some contacts and delaying others. On six occasions the Question mark was forced away from its flight track to refuel, once over Oceanside
Oceanside, California
-2010:The 2010 United States Census reported that Oceanside had a population of 167,086. The population density was 3,961.8 people per square mile...
and five times over El Centro. Maintaining contact formation became more difficult as the weight of the planes changed during transfer, especially since the refueling pilot could not observe the Question Mark. Capt. Hoyt developed a system whereby Lt. Woodring tugged on a string tied to the pilot's arm if the C-1's speed was excessive. Early in the flight a window blew out of the C-2's cabin, but a replacement was eventually hauled up and installed by Sgt. Hooe.
End of the flight
Although the crew flew the plane at slow cruising speeds to nurse the engines, they were eventually overstressed from extended use. The left engine began losing power as early as the third day. Sgt. Hooe, taping down his trouser cuffs, wearing a parachute, and connected by a lifeline, attempted to service them from the makeshift catwalks but the inflight lubricating systems only delayed and could not prevent engine wear. After the cylinders began missing, the Question Mark shortened its loops to remain within gliding distance of Van Nuys. Eaker was able to clear fouled spark plugSpark plug
A spark plug is an electrical device that fits into the cylinder head of some internal combustion engines and ignites compressed fuels such as aerosol, gasoline, ethanol, and liquefied petroleum gas by means of an electric spark.Spark plugs have an insulated central electrode which is connected by...
s by completely opening the throttles.
On the afternoon of January 7, the left wing engine quit. Hooe went out on the catwalk to attempt repairs, immobilizing the windmilling propeller with a rubber hook. Eaker increased throttle on the remaining two engines to maintain flight while repairs were attempted, and they too began to strain. The plane lost altitude from 5,000 to 2550 feet (777.2 m) before Hooe was called back inside and the decision made to land.
The Question Mark landed under power at Metropolitan Airport at 2:06 p.m., 150 hours, 40 minutes, and 14 seconds after takeoff. The left engine had seized because of a pushrod failure, and the others all suffered severe rocker arm
Rocker arm
Generally referred to within the internal combustion engine of automotive, marine, motorcycle and reciprocating aviation engines, the rocker arm is a reciprocating lever that conveys radial movement from the cam lobe into linear movement at the poppet valve to open it...
wear.
Results
Refueled 37 times and resupplied six others, with 12 of the 43 replenishments taking place at night, the Question Mark took on 5660 gallons (21,425.4 l) of fuel, 245 gallons (927.4 l) of oil, and supplies of food and water for its five-man crew. Hoyt and Refueling Airplane No. 1, flying from Rockwell and a backup airport at Imperial, CaliforniaImperial, California
Imperial is a city in Imperial County, California. Imperial is located north of El Centro. As of the 2010 census, the city had a population of 14,758. It is part of the El Centro metropolitan area. The City of Imperial is a bustling center in the Imperial Valley due to its central location in The...
, resupplied Question Mark 27 times (ten at night), while Lt. Moon's crew at Van Nuys flew 16 sorties, two at night. In all, the flight broke existing world records for sustained flight (heavier-than-air), refueled flight, sustained flight (lighter-than-air), and distance.
All five crew members were decorated with the Distinguished Flying Cross
Distinguished Flying Cross (United States)
The Distinguished Flying Cross is a medal awarded to any officer or enlisted member of the United States armed forces who distinguishes himself or herself in support of operations by "heroism or extraordinary achievement while participating in an aerial flight, subsequent to November 11, 1918." The...
at a ceremony held at Bolling Field on January 29. The crews of the tankers, on the other hand, went unrecognized. Eventually all six received letters of commendation for their participation, but it was 47 years before their vital role in the operation was recognized with decorations. By then only Hoyt and Hopkins remained living, but both personally received Distinguished Flying Crosses on May 26, 1976.
Followup efforts and legacy
Eaker was involved in a second attempt at aerial refueling in September 1929. Piloting a Boeing Model 95Boeing Model 95
-See also:...
mail plane nicknamed the Boeing Hornet Shuttle on a transcontinental endurance flight eastbound from Oakland, California
Oakland, California
Oakland is a major West Coast port city on San Francisco Bay in the U.S. state of California. It is the eighth-largest city in the state with a 2010 population of 390,724...
, he was refueled in flight by C-1s and Boeing Model 40 aircraft. Over Cleveland, Ohio
Cleveland, Ohio
Cleveland is a city in the U.S. state of Ohio and is the county seat of Cuyahoga County, the most populous county in the state. The city is located in northeastern Ohio on the southern shore of Lake Erie, approximately west of the Pennsylvania border...
, a Boeing refueling crew accidentally dropped a five-gallon can of oil through his wing, ending the first attempt. On a second attempt westbound, his engine quit over Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
when dirt clogged the fuel line, forcing him to crashland in the mountains near Salt Lake City.
The flight of the Question Mark inspired a rash of projects to break the endurance record. In 1929 alone 40 flights were attempted, all by civilians, and nine succeeded in surpassing Question Marks record. At the end of 1929 the record stood at over 420 hours, established by Dale "Red" Jackson and Forest E. "Obie" O'Brine in the Curtiss Robin
Curtiss Robin
|-See also:-References:NotesBibliography*Bowers, Peter M. Curtiss Aircraft 1907–1947. London: Putnam, 1979. ISBN 0-370-10029-8.-External links:* * ****...
Greater St. Louis.
The Air Corps followed up the flight of the Question Mark with a mission to demonstrate its applicability in combat. On May 21, 1929, during annual maneuvers, a Keystone LB-7 piloted by Lt. Moon took off from Fairfield Air Depot
Wright-Patterson Air Force Base
Wright-Patterson Air Force Base is a United States Air Force base in Greene and Montgomery counties in the state of Ohio. It includes both Wright and Patterson Fields, which were originally Wilbur Wright Field and Fairfield Aviation General Supply Depot. Patterson Field is located approximately...
in Dayton, Ohio
Dayton, Ohio
Dayton is the 6th largest city in the U.S. state of Ohio and the county seat of Montgomery County, the fifth most populous county in the state. The population was 141,527 at the 2010 census. The Dayton Metropolitan Statistical Area had a population of 841,502 in the 2010 census...
, on a simulated mission to New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
via Washington, D.C. Plans were for the bomber to be refueled in flight several times, drop a flash bomb over New York harbor, then return to Dayton non-stop, again by way of Washington. Moon had 1st Lt. John Paul Richter, who had been a hose handler on the first-ever refueling aerial refueling mission on May 28, 1923, as a member of his five-man crew. The C-1 tanker employed to refuel the LB-7 was flown by Capt. Hoyt and two enlisted men. While attempting an air refueling en route from Dayton to Washington, icing forced the tanker to land in Uniontown, Pennsylvania
Uniontown, Pennsylvania
Uniontown is a city in Fayette County, Pennsylvania, southeast of Pittsburgh and part of the Pittsburgh Metro Area. Population in 1900, 7,344; in 1910, 13,344; in 1920, 15,692; and in 1940, 21,819. The population was 10,372 at the 2010 census...
, where it got stuck in mud. After flying to New York, the LB-7 was forced to land at Bolling Field. The next day the tanker joined the bomber and both flew to New York, where they made a public demonstration of air refueling and four dry runs.
Of the 16 Army aviators involved in the project, six later became general officers. Spaatz, Eaker and Quesada played important roles in the United States Army Air Forces
United States Army Air Forces
The United States Army Air Forces was the military aviation arm of the United States of America during and immediately after World War II, and the direct predecessor of the United States Air Force....
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. Spaatz rose to commanding general of the Army Air Forces and became the first Chief of Staff of the United States Air Force
Chief of Staff of the United States Air Force
The Chief of Staff of the Air Force is a statutory office held by a four-star general in the United States Air Force, and is the most senior uniformed officer assigned to serve in the Department of the Air Force, and as such is the principal military advisor and a deputy to the Secretary of the...
. Eaker commanded the Eighth
Eighth Air Force
The Eighth Air Force is a numbered air force of the United States Air Force Global Strike Command . It is headquartered at Barksdale Air Force Base, Louisiana....
and Mediterranean Allied Air Forces. Quesada commanded the IX Tactical Air Command
Ninth Air Force
The Ninth Air Force is a numbered air force of the United States Air Force's Air Combat Command . It is headquartered at Shaw Air Force Base, South Carolina....
in France. Strickland, Hoyt and Hopkins all became brigadier generals in the United States Air Force, and the Brigadier General Ross G. Hoyt Award is issued annually for the best air refueling crew in the Air Force. Halverson, though he rose only to colonel, led the HAL-PRO ("Halverson Project") detachment, 12 B-24 Liberator
B-24 Liberator
The Consolidated B-24 Liberator was an American heavy bomber, designed by Consolidated Aircraft of San Diego, California. It was known within the company as the Model 32, and a small number of early models were sold under the name LB-30, for Land Bomber...
s that bombed the Ploieşti
Ploiesti
Ploiești is the county seat of Prahova County and lies in the historical region of Wallachia in Romania. The city is located north of Bucharest....
oil refineries in 1942, and was the first commander of the Tenth Air Force
Tenth Air Force
The Tenth Air Force is a numbered air force of the United States Air Force Reserve Command . It is headquartered at Naval Air Station Joint Reserve Base Fort Worth, Texas....
.
Moon, a bomber pilot, became an influential member of the "Bomber Mafia
Bomber Mafia
The Bomber Mafia were a close-knit group of American military men who believed that long-range heavy bomber aircraft in large numbers were able to win a war...
" at the Air Corps Tactical School
Air Corps Tactical School
The Air Corps Tactical School, also known as ACTS and "the Tactical School", was a military professional development school for officers of the United States Army Air Service and United States Army Air Corps, the first such school in the world. Created in 1920 at Langley Field, Virginia, it...
from 1933 to 1936, but died on November 19, 1937, awaiting retirement from the service at the age of 45. Solter, a pursuit pilot, was killed in an accident flight-testing an all-metal trainer at Randolph Field
Randolph Air Force Base
Randolph Air Force Base is a United States Air Force base located east-northeast of San Antonio, Texas. The base is under the jurisdiction of the 902d Mission Support Group, Air Education and Training Command ....
, Texas, in September 1936. Elmendorf, while not having a flying role in the project, was an accomplished test pilot and was killed on January 13, 1933, testing the Y1P-25
Consolidated P-30
|-See also:-References:NotesBibliography* Angelucci, Enzo. and Peter M. Bowers, The American Fighter. New York: Orion Books, 1987. ISBN 0-517-56588-9....
at Wright Field
Wright Field
Wright Field was an airfield of the United States Army Air Corps and Air Forces near Riverside, Ohio. From 1927 to 1947 it was the research and development center for the Air Corps, and during World War II a flight test center....
, Ohio.
The Question Mark was re-engined with 300 hp Wright R-975 engines in 1931, and redesignated in the practice of the day as a C-7. It served out its service life as the transport airplane for the 22nd Observation Squadron
22d Tactical Drone Squadron
The 22d Tactical Drone Squadron is an inactive United States Air Force unit. It was last assigned to the 432d Tactical Drone Group, stationed at Davis-Monthan AFB, Arizona. It was inactivated on 1 Apr 1979.-World War I:...
at Pope Field, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, and was surveyed (scrapped) at Randolph Field in 1934. A major component of the refueling device is in the collections of the Historical Society of Berks County
Historical Society of Berks County
Founded in 1869, the Historical Society of Berks County is a museum and library located in Reading, Pennsylvania. The Society's mission, as described on its website, is "to focus attention on the unique local history, the vast material culture, and the diverse cultural heritage of Berks County by...
in Reading, PA.
External links
- "Flight of the Question Mark", Air Mobility Command History Office. Several high resolution images of crew and flight.
- NMUSAF photo of Question Mark post-flight
- NMUSAF photo of Douglas C-1 in flight
- Davis-Monthan C.B. Cosgrove Collection, 13th photo down is of message written to Major Spaatz on side of PW-9 fighter of 95th PS at Rockwell Field
- National Museum of the USAF fact page: Atlantic-Fokker C-2A "Question Mark" with images
- Walter J. Boyne, "Question Mark", AIR FORCE Magazine March 2003 Vol. 86 No. 3 pdf file has article images
- "Question mark", Time Magazine January 14, 1929
- USAF Historical Studies Office article about the mission
- Belleville News-Democrat September 8, 2007, "Flyboys from Sparta held record", details both the Curtiss Robin and Stinson Hunter Brothers flights