Tag Archives: Air Mail

18–19 February 1934

February 19, 2024AviationAir Mail, c/n 1137, City of Los Angeles, Douglas Aircraft Company, Douglas DC-1, Edward Vernon Rickenbacker, Grand Central Air Terminal, Grand Central Airport, Lineas Aéreas Postales Espanolas, NC223Y, Paul Ernest Richter Jr., Silas Amos Morehouse, Transcontinental & Western Air Inc., William John ("Jack") Frye, Wright Cyclone SGR-1820-F3Bryan Swopes

Transcontinental & Western Air, Inc.’s Douglas DC-1, NC223Y, “City of Los Angeles,” at Grand Central Air Terminal, Glendale, California, 1934. This is the aircraft that carried the mail on a transcontinental flight, 18–19 February 1934. (San Diego Air & Space Museum Archives)

18–19 February 1934: The final commercial air mail flight before United States Army took over the U.S. air mail set a new transcontinental speed record. An estimated 15,000 people were present at the Grand Central Air Terminal to witness the takeoff.

Because of a controversy as to how several long-term air mail contracts had been issued by the U.S. Postal Service, President Franklin Delano Roosevelt cancelled all of the commercial contracts by executive order, then ordered the U.S. Army to take over flying of the mail.

The airplane, the prototype Douglas Commercial Model 1 (DC-1), NC223Y, took off from Glendale, California, under the command of William John (“Jack”) Frye, vice president and chief pilot of Transcontinental and Western Air, Inc. Two other T.W.A. pilots, Silas Amos (“Si”) Morehouse and Paul Ernest Richter, Jr., completed the flight crew. Also aboard were Edward Vernon (“Eddie”) Rickenbacker, president of Eastern Air Transport, the leading US. fighter ace of World War I. Six journalists rode as passengers during the flight. Approximately 3,300 pounds (1,497 kilograms) of mail were carried.

Douglas DC-1 NC223Y, “City of Los Angeles,” at Grand Central Air Terminal, Glendale, California, 1934. (San Diego Air & Space Museum Archives)

The route of the flight was from Glendale, California, to Albuquerque, New Mexico; Kansas City, Kansas; Columbus, Ohio; and Newark, New Jersey. The DC-1, named City of Los Angeles, departed Grand Central Air Terminal at 8:56 p.m., Pacific Standard Time (04:56 UTC) and arrived at Newark after a total elapsed time of 13 hours, 4 minutes, 20 seconds. The refueling stops at Albuquerque, Kansas City and Columbus were approximately ten minutes each.

Transcontinental & Western Douglas DC-1, NC223Y, “City of Los Angeles,”at Grand Central Air Terminal, 1934. (San Diego Air & Space Museum Archives)

The Los Angeles Times reported:

SKY TRAVEL MARK SET

NEW YORK TRIP TIME SLASHED

Latest T.-W.A. Liner Reaches Goal in Thirteen Hours, Four Min., Twenty Sec.

Best Passenger Transport Run Eclipsed by More than Six Hours

[Aviation writer for the Los Angeles Times, Jean Bosquet, on invitation of officials of Transcontinental and Western Air, Inc., represented this newspaper on the history-making, record-smashing flight of the air line’s new Douglas transport plane from Los Angeles to New York.]

BY JEAN BOSQUET

NEW YORK, Feb. 19. (Exclusive) Los Angeles to New York in thirteen hours, four minutes and twenty seconds.

Incredible as it may seem, an air liner of Transcontinental and Western Air, Inc., constituting herself a winged representative of the American aviation industry, accomplished today the feat of carrying a capacity load of passengers and air mail across the continent in slightly more than thirteen hours, faster than the best previous time of a passenger plane in coast-to-coast flight by more than six hours.

Shattering all existing speed and efficiency records for multimotored transport aircraft, the T.-W.A. liner City of Los Angeles performed the amazing gesture designed, in part, to impress the Federal government with the high efficiency attained by civilian aviation in the United States.

DEBUT AND CHALLENGE

The performance of the Douglas monoplane, making its maiden flight across the continent, served as a protest against the government decree threatening the existence of the aviation industry by cancellation of air-mail contracts held by major air lines.

The great gray liner’s epochal flight was at once a debut and a challenge.

Slipping through the night skies, the swift monoplane rushed over almost 1500 miles of continent between Los Angeles and Kansas City in seven hours and eight minutes, elapsed time, maintaining an average of 210 miles an hour. A ten-minute stop was made at Albuquerque for refueling. The 715 miles between Los Angeles and the New Mexico point were spanned in three hours and fifteen minutes, 220 miles an hour being her average speed. Normal flying time for this run, in ships to be replaced next April by a fleet of these Douglas planes,is at present more than seven hours.

DETAILS OF FLIGHT

The City of Los Angeles took off from Grand Central Air Terminal in 8:56 p.m. yesterday and reached Albuquerque as 12:11 a.m. today, Pacific standard time. Three hours and forty-four minutes were required for the next leg of the maiden flight, to Kansas City, which point was reached at 4:05 a.m., Pacific standard time.

Refueling in ten minutes, the T.W.A. transport sped eastward, reaching Newark less than six hours after taking off from Kansas City and that following a stop at Columbus, O.

At Columbus the landing was made in a flurry of snow. Undaunted by threat of storm, the angle of the blades on the flashing controllable-pitch propellers was changed and the mighty craft stuck its nose into the flurries and climbed like a condor until it road above the storm at 18,500 feet.

At Lebanon, Pa., it had dropped to 14,000 feet and, riding the radio beam through a dull and cloudy sky, it soared into Newark under a broken ceiling of approximately 7000 feet.

SHIP STEAM-HEATED

When the ship had reached its highest altitude, some of the six news writers and cameramen on board were seized with violent headaches. The portable oxygen tank was brought out and everybody had a few whiffs “to bring down the altitude.” Outside sleet smacked the metal sides of the aircraft and the temperature was 30 deg. below zero. Inside it was warm and cozy—the ship is steam-heated.

From Columbus to a point east of Allentown, Pa., somewhat off the regular course, the plane was flying completely blind, depending on the radio beacons. Near the Delaware Water Gap the weather was clearing and the transport made its landing without difficulty before the fog caught up with it.

STOP ELIMINATED

A third stop scheduled for Pittsburgh was eliminated, when the storm made it advisable to take on a heavier load of fuel at Columbus for the direct hop to New York.

Although a sixty-mile tail wind at the 18,500-foot level enabled the aircraft to increase its speed to between 240 and 260 miles an hour, the plane for most of the distance was not helped by favoring winds. For the most part, according to Capt. Rickenbacker, there were cross winds. Fair weather was encountered most of the distance to Columbus.

The amazing performance was unexpected even to T.W.A. officials, who had hoped their new liner would make the flight in fifteen hours with favorable weather. Aviation circles nationally were astonished by the speed of the transport, product of scientific engineering genius of the Southland.

SPLENDID SHOWING

It was as though the great ship were aware of the trust reposed in her by her owners and by the rest of the nation’s aviation industry as well, when she roared out of Los Angeles, swept majestically over 12,000-foot mountain peaks and burst into the mist of morning over Kansas City.

It was not alone the tremendous speed of the sleek liner which stood out as her flight progressed. She astonished a group of newspapermen and surprised even the flight host, Capt. Eddie Rickenbacker, World War ace, with the quiet of her luxurious cabin, her steadiness in flight over mountain country, and the ease with which she sped on her course, the roaring of her two Wright Cyclones heard but faintly in her cabin.

As she made her record-smashing way eastward her passengers slept in reclining chairs held steadier than berths in railroad trains.

LAST MAIL CARGO

In the after compartment of the liner was the last consignment of mail to be carried by civilian aircraft, the governmental order canceling air-mail contracts taking effect three hours after the ship took off in Los Angeles.

Veteran pilots forming the liner’s crew grimly hummed “The Last Round-up” as they sent the swift craft into the east.

The nine-ton monoplane with her 3300-pound pay load swept over treacherous terrain which now must be spanned by army aircraft and pilots ill-equipped for the task.

Leaving Los Angeles the craft climbed to a height of 14,000 feet, rushing upward at the rate of 600 feet a minute at a speed of 190 miles an hour. Soon she was clearing the loftiest mountain peaks along her course by at least 2000 feet, disdainfully soaring over them.

VETERAN AVIATORS

At her controls when the City of Los Angeles began her flight were Jack Frye, veteran airman and vice president of T.-W.A.; Paul Richter, superintendent of operations for the line’s western region, and Si Morehouse, senior pilot of T.-W.A. The combined flight hours of the three veterans totaled more than 15,000. Commenting on this during the flight, Capt. Rickenbacker pointed out the perilous undertaking of the army pilots now flying the mails with averages of less than 400 hours each.

Other pilots replaced Richter and Morehouse as division points were reached, but Frye remained in the ship’s control room throughout her record breaking flight.

—Los Angeles Times, Vol. III, 20 February 1934, Page 1, Column 6, and Page 2, Column 4

Douglas DC-1 X223Y, at Clover Field, Santa Monica, California, 1 July 1933. (San Diego Air & Space Museum, Michael Blaine Collection, Catalog #: Blaine_00263)

The Douglas DC-1 was a prototype commercial transport, built by the Douglas Aircraft Company, Santa Monica, California. It was a twin-engine, all-metal, low-wing monoplane with conventional landing gear. It had a flight crew of two pilots, and seats for 12 passengers.

The new airplane had been requested by Transcontinental and Western Air, Inc., in August 1932. Originally intended as a three-engine transport, the new airliner was required to have a maximum speed of at least 185 miles per hour (298 kilometers per hour) and a service ceiling of 21,000 feet (6,400 meters). It would be required to take off from Winslow, Arizona—at 4,941 feet (1,506 meters) above Sea Level, the highest airfield in the T.W.A. route system. It was required to carry more passengers than the Boeing Model 247, and to have a landing speed of 65 miles per hour (105 kilometers per hour).

The DC-1 was 60 feet, 0 inches (11.288 meters) long, with a wing span of 85 feet, 0 inches (25.908 meters), and height of 16 feet, 0 inches (4.877 meters). Its empty weight was 11,780 pounds (5,343 kilograms), and gross weight, 17,500 pounds (7,938 kilograms).

Passenger cabin of the Douglas DC-1. (Dick Whittington Studio)

Reclining seats in the passenger cabin of the Douglas DC-1. (Dick Whittington Studio)

The DC-1 was powered by two supercharged, air-cooled, Wright Cyclone SGR-1820-F3 nine-cylinder radial engines, These engines had a compression ratio of 6.4:1 and required 87-octane gasoline. They were rated at 700 horsepower at 1,950 r.p.m. They turned three-bladed variable-pitch propellers through a 16:11 gear reduction. The -F3 was 3 feet, 11-3/16 inches (1.199 meters) long, 4 feet, 5¾ inches (1.365 meters) in diameter, and weighed 1,047 pounds (475 kilograms).

The DC-1 had a cruise speed of 190 miles per hour (306 kilometers per hour) and maximum speed of 210 miles per hour (338 kilometers per hour). Its range was 1,000 miles (1,609 kilometers), and the service ceiling was 23,000 feet (7,010 meters).

Only one DC-1 was built. It was rolled out of its hangar 22 June 1933. Registered X223Y, it made its first flight, 1 July 1933, at Clover Field, Santa Monica, California, with test pilots Carl Cover and Fred Herman in the cockpit.

The prototype Douglas DC-1, X223Y, takes off from Clover Field, Santa Monica, California, 1 July 1933. (Airport Journals)

The Douglas DC-1, X223Y, in flight. (Larry Westin)

NC223Y was retired from passenger service in 1936. T.W.A. loaned it to the U.S. government for high altitude research. It was then sold to Howard Hughes. In May 1938 NC223Y was sold to Viscount Forbes of the United Kingdom, 27 May 1938, transported across the Atlantic aboard a freighter, then registered G-AFIF, 25 June 1938. The airplane was re-sold to France in September 1938.

Spanish-registered Douglas DC-1 EC-AGN, owned by Lineas Aéreas Postales Espanolas. (Iberia Airlines)

The DC-1 was again sold, this time to Spanish Republican government, and operated by Lineas Aéreas Postales Espanolas, also known as LAPE. The airplane made a forced landing at Malaga, Spain, in December 1940. It was damaged beyond repair.

Wreck of the Douglas DC-1, Malaga, Spain. (Weird Wings)

The single DC-1 prototype led to an order for 20 improved 14-passenger DC-2s for T.W.A. This, in turn, resulted in the development of the legendary Douglas DC-3.

22 November 1935

November 22, 2023AviationAir Mail, Airliner, c/n 558, China Clipper, Edwin Charles Musick, Flying Boat, Frederick Joseph Noonan, Glenn L. Martin Company, Martin M-130, NC14716, Pan American Airways, Robert Oliver Daniel Sullivan, Trans-Pacific Flight, Transoceanic FlightBryan Swopes

22 November 1935: The Pan American Airways flying boat, China Clipper, a Martin M-130, NC14716, departed Alameda, California (an island in San Francisco Bay) at 3:46 p.m., Friday, and arrived at Honolulu at 10:39 a.m., Saturday, completing the first leg of a five-day trans-Pacific flight to Manila in the Philippine Islands.

The aircraft commander was Captain Edwin Charles Musick, with First Officer Robert Oliver Daniel (“Rod”) Sullivan. The navigator was Frederick Joseph Noonan, who would later accompany Amelia Earhart on her around-the-world flight attempt. There were also a Second Officer and two Flight Engineers. The cargo consisted of 110,000 pieces of U.S. Mail.

Captain and Navigator with mail sacks, prior to flight. — Captain Edwin Musick and R.O.D. Sullivan, at the center of the image, next to the China Clipper before leaving San Francisco Bay with the first transpacific airmail, 22 November 1935. The three men at the right of the image are (left to right) Postmaster General James Farley; Assistant Postmaster General Harllee Branch; and Pan American Airways’ President Juan Trippe.

Pan Am personnel called the Clipper “Sweet Sixteen,” referring to its Civil Aeronautics Board registration number, NC14716. The airplane and Humphrey Bogart starred in a 1936 First National Pictures movie, “China Clipper.”

NC14716 was the first of three Martin M-130 four-engine flying boats built for Pan American Airways and was used to inaugurate the first commercial transpacific air service from San Francisco to Manila in November, 1935. Built at a cost of $417,000 by the Glenn L. Martin Company in Baltimore, Maryland, it was delivered to Pan Am on October 9, 1935. The airplane’s serial number was 558.

Pan American Airways’ Martin M-130m China Clipper, NC14716, over San Francisco, California. (Clyde Herwood Sunderland, Jr./Library of Congress 94509045)

The M-130 was operated by a flight crew of 6–9, depending on the length of the flight, plus cabin staff, and could carry 18 passengers on overnight flights, or a maximum 36 passengers.

Cutaway illustration of Pan American Airways’ Martin M-130 China Clipper. Detail from larger image. (National Air and Space Museum SI-89-1216-A)

Martin M-130 three-view illustration. (Flight, The Aircraft Engineer & Airships, Vol. XXVII, No. 1361, 24 January 1935, Page 99) — Martin M-130 3-view drawing. (Flight)

The Martin M-130 was 90 feet, 10.5 inches (27.699 meters) long with a wingspan of 130 feet, 0 inches (39.624 meters). It was 24 feet, 7 inches (7.493 meters) high. The total wing area was 2,315 square feet (215 square meters), including the “sea wings”. Its maximum takeoff weight was 52,252 pounds (23,701 kilograms).

The flying boat was powered by four air-cooled, supercharged Pratt & Whitney Twin Wasp S2A5-G two-row 14-cylinder radial engines with a compression ratio of 6.7:1. They had a normal power rating 830 horsepower at 2,400 r.p.m., and 950 horsepower at 2,550 r.p.m. for takeoff. They drove three-bladed Hamilton Standard Hydromatic constant-speed propellers through a 3:2 gear reduction. The S2A5-G was 3 feet, 11.88 inches (1.216 meters) in diameter, 4 feet, 8.75 inches (1.441 meters) long, and weighed 1,235 pounds (560 kilograms).

Martin M-130 NC14716, right rear quarter view.

The airplane had a cruise speed of 130 miles per hour (209 kilometers per hour) and a maximum speed of 180 miles per hour (290 kilometers per hour). The M-130’s service ceiling was 10,000 feet (3,048 meters). Its range was 3,200 miles (5,150 kilometers).

Martin M-130, NC14716, China Clipper, moored at some distant exotic locale. (Unattributed)

3 November 1926

November 3, 2023AviationAir Mail, Airco DH.4, Aircraft Accident, C.A.M. No. 2, Charles A. Lindbergh, Charles Augustus Lindbergh, Contract Air Mail, De Havilland DH-4B, Parachute, Robertson Aircraft CorporationBryan Swopes

Chief Pilot Charles A. Lindbergh in the cockpit of Robertson Aircraft Corporation’s modified De Havilland DH-4, Number 109, 15 May 1926. (Swenson Studio)

Charles A. Lindbergh, circe 1926. (SDA&SM) — Charles A. Lindbergh, circa 1926. (San Diego Air & Space Museum)

3 November 1926: Charles Augustus Lindbergh, chief pilot of the Robertson Aircraft Corporation, St. Louis, Missouri, was flying a night air mail route between St. Louis and Chicago, Illinois. His airplane was a modified De Havilland DH-4B, U.S. Postal Service Airmail Plane Number 109.

Lindbergh was flying Contract Air Mail Route 2, or “C.A.M. No. 2.” He departed St. Louis at 4:20 p.m. and made his first stop at Springfield, Illinois, at 5:15 p.m. He then continued on the second stage, Springfield to Peoria, Illinois.

Visibility was poor, about a half-mile (800 meters) in fog. Lindbergh flew at 600 feet (183 meters) but was unable to see the ground. Near the air field at Peoria, he could see lights from 200 feet (61 meters) altitude, but was unable to land.

After circling for 30 minutes, he continued toward Chicago. Lindbergh occasionally saw lights on the ground through the fog, but with his fuel running low, he decided that he was going to have to abandon his airplane. He headed out over more open country and climbed to 14,000 feet (4,267 meters).

Robertson Aircraft Corporation Dh-4 No. 109. The airplane's fuselage is painted "Tuscan Red" and the wings and tail surafces are silver. The lettering on the side is white. (Minnesota Historical Society) — Robertson Aircraft Corporation DH-4 No. 109, 15 May 1926. (Swenson Studio/Minnesota Historical Society)

At 8:10 p.m., the de Havilland’s fuel supply was exhausted and the engine stopped. Lindbergh switched off the battery and magnetos, then stepped over the side. He immediately pulled the ripcord of his parachute and safely descended to the ground.

Airmail Plane Number 109 crashed on the farm of Charles and Lillie Thompson, near Covell, a small town southwest of Bloomington, Illinois. Lindbergh had been unable to find the wreck in the darkness, but in daylight, it was clearly visible just 500 feet (152 meters) from the Thompson’s house.

This was the fourth time that Charles Lindbergh has used a parachute to escape from an airplane. The last time was just six weeks earlier.

Charles A. Lindbergh (fourth from left) with the wreckage of Robertson Aircraft Corporation DH-4 No. 112, 16 September 1926. (Yale University Library)

He resigned from Robertson Aircraft and formed a group to finance and build the Spirit of St. Louis. Charles Augustus Lindbergh flew his new airplane across the Atlantic Ocean, non-stop, solo, 20–21 May 1927.

Robertson Aircraft Corporation's four de Havilland DH-4s, numbers 109, 110, 111, and 112. — Robertson Aircraft Corporation’s four de Havilland DH-4s, numbers 109, 110, 111, and 112. The airplanes’ fuselages are painted “Tuscan Red” and their wings and tail surfaces are silver. The lettering on their sides is white. No. 112 is the last airplane in this group. “Lucky Lindy” bailed out of it on the night of 16 September 1926.

The Airco DH.4 was a very successful airplane of World War I, designed by Geoffrey de Havilland. The DH.4 (DH-4 in American service) was a two-place, single-engine, two-bay biplane with fixed landing gear. The fuselage and wings were constructed of wood and covered with doped fabric. The airplane was produced by several manufacturers in Europe and the United States.

The DH-4 was 30 feet, 5 inches (9.271 meters) long with a wingspan of 42 feet, 8 inches (13.005 meters) and height of 10 feet, 6 inches (3.200 meters). It had an empty weight of 2,391 pounds, (1,085 kilograms) and gross weight of 4,297 pounds (1,949 kilograms). Fuel capacity was 67 gallons (254 liters).

Army Air Service DH-4s were powered by Liberty 12 aircraft engines in place of the Rolls-Royce Eagle VII V-12 of the British-built DH.4 version. The L-12 was water-cooled, normally-aspirated, 1,649.34-cubic-inch-displacement (27.028 liter), single overhead cam (SOHC) 45° V-12 engine. It produced 408 horsepower at 1,800 r.p.m. The L-12 as a right-hand tractor, direct-drive engine and it turned turned a two-bladed fixed-pitch wooden propeller. The Liberty 12 was 67.375 inches (1.711 meters) long, 27.0 inches (0.686 meters) wide, and 41.5 inches (1.054 meters) high. It weighed 844 pounds (383 kilograms).

The Liberty 12 aircraft engine was designed by Jesse G. Vincent of the Packard Motor Car Company and Elbert J. Hall of the Hall-Scott Motor Company. This engine was produced by Ford Motor Company, as well as the Buick and Cadillac Divisions of General Motors, The Lincoln Motor Company (which was formed by Henry Leland, the former manager of Cadillac, specifically to manufacture these aircraft engines), Marmon Motor Car Company and the Packard Motor Car Company. Hall-Scott was too small to produce engines in the numbers required.

The DH-4 had a maximum speed of 124 miles per hour (200 kilometers per hour), service ceiling of 19,600 feet (5,974 meters) and range of 400 miles (644 kilometers).

Many DH-4s were rebuilt as DH-4Bs. These can be identified by the relocated pilot’s cockpit, which was moved aft, closer to the observer’s position. The an enlarged fuel tank was place ahead of the pilot’s cockpit. Following World War I, many were rebuilt with tubular metal frames for the fuselage, replacing the original wooden structure. These aircraft were redesignated DH-4M.

The prototype American DH-4, Dayton-Wright-built airplane, is in the collection of the Smithsonian Institution National Aviation and Space Museum.

Wreck of Robertson Aircraft Corporation's de Havilland DH-4, Number 109. (San Diego Air and Space Museum Archives) — Wreck of Robertson Aircraft Corporation’s de Havilland DH-4, Number 109. (San Diego Air and Space Museum Archives)

1 October 1947

October 1, 2023AviationAir Mail, Helicopter, Los Angeles Airways, Pratt & Whitney R-985 AN-5, Pratt & Whitney Wasp Jr. T1B4, Sikorsky Aircraft Corporation, Sikorsky S-51, Terminal Annex Post OfficeBryan Swopes

1 October 1947: Los Angeles Airways began regularly scheduled air mail service in Los Angeles, using the Sikorsky S-51 helicopter.

“. . . the U.S. Civil Aeronautics Board awarded LAA the route authorities to operate local air mail services in Southern California using the Sikorsky S-51. Before long, LAA was operating a twice-a-day mail service between the main downtown post office and Los Angeles International Airport along with a small package air express service.

“With a fleet of five S-51s, LAA’s first year of operations resulted in 700 tons of mail being carried with approximately 40,000 landings throughout the Los Angeles metropolitan area. The small operation maintained a 95% reliability rate and by the time it began its small package air express service in 1953, it was annually moving nearly 4,000 tons of mail a year.

“In July 1951 the CAB awarded LAA’s reliable helicopter operation the rights for passenger services which started in November 1954 with larger Sikorsky S-55 helicopters while the smaller S-51s continued the mail and small package services. . . .”

— Tails Through Time, http://aviationtrivia.blogspot.com/2010/06/on-1-october-1947-los-angeles-airways.html

The S-51 was a commercial version of the Sikorsky R-5 series of military helicopters. It was a four-place, single-engine helicopter, operated by one pilot. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction. The main rotor consisted of three fully-articulated blades built of metal spars and plywood ribs and covered with two layers of fabric. (All metal blades soon became available.) The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right.) The tail rotor was mounted on the helicopter’s left side in a pusher configuration. It turned clockwise as seen from the helicopter’s left.

The helicopter’s fuselage was 41 feet, 7.5 inches (12.687 meters) long. The main rotor had a diameter of 48 feet (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.565 meters), giving the helicopter an overall length of 57 feet, 1 inch (17.399 meters). It was 13 feet, 1.5 inches (4.001 meters) high. The landing gear tread was 12 feet (3.7 meters). The S-51 had an empty weight of 4,050 pounds (1,837 kilograms) and maximum takeoff weight of 5,500 pounds (2,495 kilograms). Fuel capacity was 100 gallons (378.5 liters).

The helicopter was powered by an air-cooled, supercharged, 986.749-cubic-inch-displacement (16.170 liter) Pratt & Whitney Wasp Jr. T1B4 (R-985 AN-5) direct-drive, nine-cylinder radial engine which was placed vertically in the fuselage behind the crew compartment. This engine was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.

The S-51 had a maximum speed (Vne) of 107 knots (123.1 miles per hour/198.2 kilometers per hour). Range was 275 miles (442.6 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914.4 meters).

Of 220 helicopters in the S-51 series built by Sikorsky, 55 were commercial models.

Los Angeles Airways Sikorsky S-51 (Viewliner) — A Los Angeles Airways Sikorsky S-51. The main rotor hub is covered. (Viewliner)

11 September 1920

September 11, 2023AviationAir Mail, Airplane No. 151, Edison Esadore Mouton, Marina Field, Monte Mouton, Reno, San Francisco, Transcontinental FlightBryan Swopes

MOUTON, Edison E., and LEVISEE, U.S. Air Mail, Reno, NV, ca. 1921 National Postal Museum, Curatorial Photographic Collection — Edison E. (“Monte”) Mouton (left) and fellow Air Mail pilot Rexford Levisee, with DH-4 at Reno, Nevada, ca. 1921. (Schoettner Foto., Reno, Nev./National Postal Museum, Curatorial Photo Collection)

11 September 1920: At 2:33 p.m., Edison E. (“Monte”) Mouton landed at Marina Field near The Presidio of San Francisco, completing the final leg of the first transcontinental air mail flight by the U.S. Postal Service. Airplane No. 151 carried 6 sacks of First Class mail from Mineola, New York.

Mouton, a pilot assigned to Salt Lake City, taking over the flight for another pilot, flew No. 151 from Reno, Nevada, to San Francisco, California, a distance of 250 miles (402 kilometers), in 1 hour, 58 minutes.

The mail sacks were immediately taken from the airplane to the central post office, where they were distributed. Two of the mail sacks were sent to Washington State and one sack to Oregon on the 4 o’clock train.

The entire cross-country flight had taken 75 hours.

Edison Esadore Mouton was born in California, 10 December 1894, the first of three children of Edward E. Mouton, a farmer, and Gertrude F. Winters Mouton.

Monte Mouton, then living in Carson City, Nevada, enlisted in the U.S. Army when the United States entered World War I. He served as a pilot with the Lafayette Escadrille in France during World War I, and was commissioned a second lieutenant, Air Service, American Expeditionary Forces. He rose to the temporary rank of colonel. Lieutenant Mouton was honorably discharged 14 May 1919. He was later an officer in the Air Corps Reserve, holding the rank of major.

Mouton was employed by the United States Aerial Mail Service from 8 September 1920 to 22 May 1927. During that time, Edison flew 3,804.54 hours and covered 369,730 miles (595,023 kilometers), flying the mail. He then became a supervising inspector for the Department of Commerce, serving for six years before resigning to enter private industry. Mouton was vice president and general manager of Nevada Air Transport, Inc., a regional airline serving the state of Nevada.

Edison E. Mouton married Miss Claire Yerington, 27 April 1921, at Reno, Nevada. (“Yerington,” as in, Yerington, Nevada. Miss Yerington’s grandfather was the superintendent of the Virginia and Truckee Railroad, which serviced the “Comstock Lode” silver mines.) Miss Yerington was described as “a strikingly beautiful blonde,” and “an intrepid devotee of the air and knows the intricacies of an automobile as well as any mechanician.” They divorced in November 1928 but were remarried 20 March 1929. They had two children.

Edison Esadore Mouton died at San Francisco Airport, San Francisco, California, 5 July 1940, an apparent suicide. He is buried at the San Francisco National Cemetery, San Francisco, California.

This Day in Aviation

Important Dates in Aviation History