THE AIRPLANES THAT FLEW, AND FLEW, AND FLEW.

In the late 1920s and early 1930s airplane manufacturers were springing up all over the country and building flying machines that pushed the boundaries of conventional designs. One of these unusual airplanes was built with hardware-store materials (except for a motorcycle engine) and acquired the nickname "Flying Bathtub." Awkward and fragile though it seemed, the Bathtub flew fast enough to win the Dayton Daily News Light Airplane Race in 1924…and one of its descendants won another air race that was quite different.

"Flying Bathtub"

ENDURANCE WAS THE NAME OF THE GAME

In 1929 a flock of ambitious aviators was striving to keep their airplanes aloft as long as possible for the purpose of setting flight endurance records. Considering the small fuel tanks of the time, transferring fuel from one airplane to another in flight was an absolute requirement and a frequent procedure.

The concept was championed by Alexander deSeversky, a Russian aviator who patented in-flight refueling in 1921. Several years later two airplanes joined up in close formation, whereupon a daredevil wing-walker with a 5-gallon can of gasoline strapped to his back climbed out on the lower airplane's wing. He hauled himself up onto the other plane's wing, walked to the fuel tank and poured in the gasoline…that was in-flight refueling defined but it appeared more stunt than science. 

Early aerial refueling

The next step in the air-to-air refueling procedure was to fly the tanker above and ahead of the receiver (the terms "tanker" and "receiver" are self-explanatory and are still used in military lingo) then lowering a fuel container on a rope to the receiver. Shortly thereafter the one-can-at-a-time procedure was replaced with rubber hoses so fuel could flow directly into the receiver's tanks. 

As more contestants and better airplanes entered the race for endurance records, the time aloft stretched into days and then weeks; the crews were supplied with food, oil, water and other necessaries via ropes from the tankers. In the absence of radio equipment, communication was accomplished by dropping written messages tied to rocks or by passing notes back and forth to the tanker crews.

Endurance flights were commonplace events in 1929; at the end of the year there had been nearly 40 attempts to post new records. Six of these 40 flights were significant in their own right and one of the six scored a number of firsts.

THE "QUESTION MARK"

Atlantic-Fokker C-2A  - The "Question Mark"

A project of the U.S. Army Air Corps, the Question Mark departed from the Los Angeles Metropolitan Field on New Years' Day 1929 with Major Carl Spaatz in command of a five-man crew. The purpose of the flight was to investigate aerial refueling operations and perhaps achieve a world record for sustained flight. When crew members were asked how long they expected to fly, they usually answered "That's the question"…hence the name of the airplane. 

A pair of tankers working in shifts delivered fuel and other supplies; at the end of the flight the tankers had transferred 5,660 gallons of gasoline, 245 gallons of oil, meals, water, etc.

The Question Mark taking on fuel

The Question Mark remained aloft for 6 days, 15 hours and 40 minutes and established new world records for sustained flight, refueled flight and distance flown. The mission would have been longer but the left engine misbehaved and Maj. Spaatz thought it best to land…a heavily loaded C-2A trimotor airplane does not perform well on two engines.

THE "FORT WORTH"

On May 19th 1929 a Ryan B-1 Brougham named Fort Worth departed Meacham Field in Fort Worth, Texas in an attempt to break the Question Mark's record for endurance. The Fort Worth was flown by low-time amateur aviators James Kelly and Reginald Robbins. The two-man crew had practiced the refueling procedure only three times…all of them on the day before takeoff.

Ryan B-1 Brougham - The Fort Worth

The plan called for refueling twice each day and lubricating the engine's rocker arms on a similar schedule, a rather daunting chore that required Kelly to crawl out of the cockpit onto a narrow catwalk to service the engine. During one of these excursions the buckle of Kelly's safety belt nicked the wood propeller, generating a crack that caused enough vibration to warrant termination of the flight. The Fort Worth landed one full week after its departure; the total time aloft was 172 hours and 32 minutes…enough to break the Question Mark's world record.

THE "CITY OF CLEVELAND"

Pilots Roy Mitchell and Bryon Newcomb departed from the Cleveland, Ohio airport on June 28th intent on breaking the endurance record the Fort Worth fliers had posted seven weeks earlier. Mitchell and Newcomb were veteran aviators and their airplane was a Stinson Detroiter named the City of Cleveland. 

 Stinson Detroiter - The City of Cleveland

Mother Nature seemed in a bad mood for the early part of the flight; several days of turbulence required constant attention to airplane control and made refueling difficult for both tanker and receiver. All the contestants for the endurance record were no doubt pushing the physical and mental limits required to stay aloft in cramped quarters for extended periods of time. Mitchell and Newcomb landed at Cleveland in the middle of the night having flown for 174 hours. 

Their flight set a new world record but they couldn't claim official status because their total time in the air failed to exceed the previous record by at least one percent…close, but no cigar.

THE "ANGELENO"

Buhl CA-5A Airsedan – The Angeleno

On the 2nd of July a Buhl Airsedan biplane named The Angeleno (translated, "a native or inhabitant of Los Angeles") departed from the Culver City Airport in west Los Angeles and joined the parade of maximum-endurance contenders. Pilots Loren Mendell and Roland Reinhart were notified shortly after takeoff that the City of Cleveland had been in the air for five days, a message that raised the bar considerably higher.

Four days later the Angeleno pilots were notified that the City of Cleveland had landed after flying for 174 hours, setting a new record; that was probably a strong incentive to continue for as long as the airplane (or its pilots) could hold up. In response to that report Mendell and Reinhart flew over the airport and dropped a message to the spectators letting them know they should "wait another week" before they would land. 

Refueling the Angeleno 

The flight came to an end on July 12th when the pilots apparently cleaned house and threw the litter overboard, damaging the empennage and threatening further flight. By the time they landed, the pilots had remained aloft for 246 hours and 43 minutes (a little more than 10 days) for a new world record. But the Angeleno's accomplishment lasted only about two weeks…another contender would establish a new record by mid-July.

THE "ST. LOUIS ROBIN"

A little deception goes a long way and such was the statement of two Curtiss-Robinson Aviation Company pilots at Lambert Field in St. Louis. Pretending to "flight-check a new engine" on a Curtiss airplane named the St. Louis Robin, pilots Dale Jackson and Forest O'Brine departed shortly after seven o'clock in the morning of July 13th and stayed aloft for 17 (count 'em, seventeen) and a half days. 

Curtiss Robin - St. Louis Robin

(Note the pilot on the catwalk performing minor maintenance)

The airplane was well-prepared for a maximum endurance flight, including a place for the pilots to sleep. 

The St. Louis Robin interior

As with the other contestants, communication was accomplished by dropping messages on the airport; on occasion the Robin's tanker aircraft became a flying blackboard with notes written in white chalk.

Forest's son, perhaps?

The flight of the St. Louis Robin became a test of man and machine endurance; no goal was set but the airborne time grew to 300 hours, then 400. When they passed the Angeleno's record Jackson and O'Brine brought the Robin home, having flown 420 hours and 21 minutes…a week more than the Angeleno. 

THE "SPOKANE SUN-GOD"

The city of Spokane (that's "spo–can," not "spo-cane") lies in the northeastern corner of Washington State and was home to an adventurous aviator named Nicholas B. Mamer, a U.S. Army Air Service pilot during World War One. After the war Mamer became involved in civilian aviation and in 1929 undertook a pioneering flight that was destined to achieve a handful of records. 

The airplane chosen for the project was a Buhl CA-6 biplane that was modified somewhat for the mission at hand. Mamer's choice of a companion for the flight was Art Walker, who would take care of mechanical problems and handle the refueling operations.

Buhl CA-6 – The Spokane Sun-God

The Sun-God's trip was not just another find-out-how-long-you-can-stay-aloft exercise, but this flight was remarkably different; the Mamer/Walker team intended to fly the first non-stop transcontinental round trip from coast to coast. The route of flight was south from Spokane to San Francisco, east to New York and westbound back to Spokane. 

At 6 pm on August 15th 1929 the Sun-God departed from Felts Field in Spokane and headed for San Francisco, the first refueling point. The second rendezvous took place over Rock Springs, Wyoming but by then it was dark; this was the first-ever aerial refueling at night. During the fuel transfer the hose got in the way of the propellor, shredding the hose and spraying the airplane with gasoline…luckily, the fuel did not ignite.

Continuing eastward, Mamer and Walker were nearly exhausted by the turbulence they encountered over Pennsylvania. But their enthusiasm was renewed by local aviators who welcomed the Sun-God as they flew over Roosevelt Field on August 18th. Mamer and Walker had been in the air for nearly 67 hours. 

On the way back to Spokane the pilots suffered a parade of problems; they had to fly through storms, they were nearly blinded by smoke from forest fires in Montana, one of the magnetos quit, the oiling system on three cylinders failed…and they needed fuel desperately. When they reached the Miles City, Montana airport Mamer dropped a note asking if they could figure out a way to refuel. A group of volunteers borrowed milk cans from a nearby creamery, filled them with gasoline, took them aloft and lowered them on a rope to Walker one can at a time…problem solved. Spokane, here we come.

Having resolved the problems of an extremely challenging flight, The Sun-God landed at Felts Field in Spokane at 2 pm on August 20th. Mamer and Walker had been in the air for 120 hours and neither had slept during the entire flight. 

The Sun-God's mission produced several firsts; the first transcontinental refueling, the first night refueling, the first refueling above 8,000 feet and to top it off, the 7,200-mile flight set a world record for non-stop mileage. The accomplishments of the Sun-God and its pilots were more than stunts; their technical achievements helped establish the basis for future military air-refueling operations. 

When the Cold War was at its hottest the U.S. Air Force deployed jet bombers capable of delivering nuclear weapons 24/7 anywhere in the world. Aerial refueling was an absolute requirement for this operation and the B-47/KC-97 teams became the workhorses of the Strategic Air Command. 

KC-97 off-loading fuel to a B-47 c.1955

The record-setting flights in 1929 set the stage for further aerial refueling developments; the most prominent was the introduction of jet-powered tankers that could match a bomber's airspeed and if necessary, could off-load 150,000 pounds of jet fuel.