Tag Archives: Flying Boat

3 July 1942

Martin XPB2M-1 Mars, Bu. No. 1520. (Hans Groenhoff Photographic Collection, Smithsonian Institution National Air and Space Museum NASM-HGC-1059)

3 July 1942: Chief Test Pilot William Kenneth Ebel, Ph.D., Vice President of Engineering for the Glenn L. Martin Company, took the  Martin Model 170, s/n 877, for its first flight, lifting off from the waters of Chesapeake Bay. Dr. Ebel’s co-pilot was Ellis Dent Shannon, who would later become the chief test pilot for Convair.

Designated XPB2M-1 Mars, Bureau of Aeronautics serial number (“Bu. No.”) 1520, by the United States Navy, the flying boat was a prototype for a long-range patrol bomber. The first rivets had been driven for the airplane’s keel 22 August 1940, and the Mars was launched 8 November 1941. During a test in December 1941, the prototype had been damaged when a runaway propeller tore away from the No. 3 engine.

 

The Martin Mars prototype was launched 8 November 1941. (Charles M. Daniels Collection, San Diego Air & Space Museum Archives, Catalog #: 15_001975)

The U.S. Navy’s experiences early in World War II led it to adopt the Consolidated B-24 Liberator as its long range bomber (PB4Y-1 and PB4Y-2 Privateer). The XPB2M-1 was converted to a transport configuration, the XPB2M-1R, in 1943. The Navy ordered twenty transport versions, designated JRM-1. By the end of the war, only six had been built and the remaining order was cancelled.

Martin Model 170 Mars (XPB2M-1 Bu. No. 1520) at the Glenn L. Martin Co. ramp, near Baltimore, Maryland, 13 May 1942 (United States Navy, National Naval Aviation Museum, NMNA 1985.0481.003)

The Martin XPB2M-1 was a large, four-engine flying boat, operated by a crew of 11 persons. It was  118 feet, 9 inches (36.195 meters) long with a wing span of 200 feet, 0 inches (60.96 meters), and height of 37 feet, 4 inches (11.379 meters). The hull had a maximum width (“beam”) of 13 feet, 6 inches (4.115 meters). The total wing area was 3,683 square feet (342.2 square meters). The flying boat had an empty weight 75,573 pounds (34,279 kilograms), and gross weight of 140,000 pounds (63,503 kilograms).

The XPB2M-1 prototype was powered by four air-cooled, supercharged, 3,347.66-cubic-inch-displacement Wright R-3350-4 engines with a compression ratio of 6.85:1. Burning 100-octane aviation gasoline, these engines had a normal power rating of 1,700 horsepower at 2,300 r.p.m., and 2,000 horsepower at 2,400 r.p.m., at Sea Level for Takeoff. They drove three-bladed 16 foot, 6 inch (5.029 meters) diameter Curtiss Electric constant-speed propellers through a 16:7 gear reduction. The R3350-4 was 5 feet, 11.5 inches (1.816 meters) long, 4 feet, 7.12 inches (1.400 meters) in diameter, and weighed 2,450 pounds (1,111 kilograms).

The prototype Mars had a maximum speed of 221 miles per hour (356 kilometers per hour) at 4,500 feet (1,372 meters). It took 27.1 minutes to climb to 10,000 feet (,048 meters), and its service ceiling was 14,600 feet (4,450 meters). The flying boat’s fuel capacity was 10,410 gallons (39,406 liters), with 664 gallons (2,514 liters) of lubricating oil. This gave it a maximum range of 4,945 statute miles (7,958 kilometers)at 135 miles per hour (217 kilometers per hour). The maximum endurance was 37.1 hours at 131 miles per hour (211 kilometers per hour).

In the patrol bomber configuration, the XPB2M-1 could carry bombs or torpedoes. It was armed with machine guns for defense.

The XPB2M-1 was assigned to VR-8 at NAS Patuxent River, 27 Nov 1943, and later transferred to VR-2 at NAS Alameda. It was withdrawn from service in March 1945, and beached at Alameda. In April 1945 it was returned to Martin Co. for JRM-1 crew training. The prototype served as a maintenance trainer until 1949. It was then broken up.

The airplane once flew from PAX in the United States to Natal, Brazil, a distance of 4,375 miles (7,041 kilometers), while carrying a payload of 13,000 pounds (5,897 kilograms).

JRM: 0 -lift over drag coefficient 0.0233, max lift over drag 16.4

Martin Mars taxi test (Charles M. Daniels Collection, San Diego Air & Space Museum Archives, Catalog #: 15_001976)
Martin Model 170 in flight. (Charles M. Daniels Collection, San Diego Air & Space Museum Archives, Catalog #: 15_001977)

Not So Graceful

     It was not so graceful as it was towed from the Martin plant into the misty bay by small auxiliary craft.

     Through the mists from following craft it looked like as large gray whale.

     It was moved slowly by the power boats down Dark Head Creek from the plant and into the channel of the bay, 15 miles north of the mouth of the Patapsco River.

     At the controls was William K. Ebel, chief test pilot and vice-president in charge of engineering at the Martin Company.

Maneuvered Slowly

     He maneuvered the Mars slowly. When the towing boats cast off and while fireboats stood by, he started each engine separately.

     It was at this point last December, during a water test, that the No. 3 propeller tore away.

     No such mishap occurred yesterday. As the motors warmed, Ebel took the flying boat in half circles, first right, then left.

     Then he “gunned” her and the Mars sailed through the water down the bay to meet boats carrying naval officials, executives of the Martin Company and Washington officials.

Twenty-Man Crew

     With the twenty-man crew headed by Pilot Ebel, Co-Pilot Ellis E. Shannon, Capt. Harold Gray of Pan American Airways and Flight Engineer Benjamin Zelubowski, the ship warmed up for thirty minutes.

     Brig. Gen. James H. Doolittle sat with Glenn L. Martin in the observer’s boat.

     Out of the sky came a not-so-small navy amphibian plane. It paced the huge flying boat down the Chesapeake and hung over its right wing as the four largest propellers in the world lifted the ship from the water.

     Together, the two planes disappeared toward the southwest. Within thirty minutes the Mars was back. It “bumped” easily four times and sat down just as easily in the water.

Martin Jubilant

     Within a few minutes it was off again. This time it met the water evenly as it landed, then was immediately taken off again.

     Its manufacturer, Glenn L. Martin, was jubilant over the flying boat’s maiden performance.

The Sun, Baltimore, Maryland, Vol. 211, No. 42, Saturday, 4 July 1942, Page 18, Columns 3 and 4, and continued on Page 4, Column 6

Martin XPB2M-1 Mars with a 1941 Piper J3C-65 Cub, NC40743. (Hans Groenhoff Photographic Collection, Smithsonian Institution National Air and Space Museum NASM-HGC-1073)

William Kenneth Ebel was born at Orangeville, Illinois, 2 January 1899. He was the son of Willam Henry Ebel, a farmer, and Nora Agnes Rubendall Ebel.

One 1 October 1918, Ebel was enlisted as a private in the Student Army Training Corps (SATC). He was trained at Heidelberg College, Tiffin, Ohio. With the end of the War, Private Ebel was discharged 20 Dec 1918.

Ebel continued his education at Heidelberg, graduating with a Bachelor of Arts (B.A.) degree in 1921, and in 1923, he completed a Bachelor of Science in Mechanical Engineering (B.S.M.E.) at the Case School of Applied Science, Cleveland, Ohio.

Also in 1921, Ken Ebel joined the 104th Observation Squadron, Maryland National Guard, based at Baltimore. He was assigned as an aviation cadet from 11 September 1923 to 3 June 1924. He was trained as a pilot at the National Guard Primary Flying School.

On 12 January 1925, William K. Ebel was commissioned as a second lieutenant, Air Service, Officers Reserve Corps. He was promoted to first lieutenant, Air Corps, 21 December 1926. He continued to serve with the Maryland National Guard

Also in 1926, Lieutenant Ebel began his career as an engineer and test pilot for the Glenn L. Martin Company.

Effective 15 February 1929, Ebel’s reserve officer’s commission was converted to first lieutenant, Air Corps.

On 21 October 1929, William Kenneth Ebel married Miss Florence E. Sherck at Seneca, Ohio. The would have two children.

Ebel was promoted to captain, Air Corps, 5 January 1935.

The first Martin Marauder, B-26-MA 40-1361, takes off for the first time at Middle River, Maryland, 25 November 1940. (U.S. Air Force)

On 25 November 1940, Ken Abel made the first flight of the Martin B-26 Marauder twin-engine medium bomber.

Ebel earned a doctorate degree in engineering (Ph.D.) from Case.

After the War, Ebel left Martin. In 1948, he became the director of the airplane division Curtiss Wright Corporation at Columbus, Ohio. In 1950 he was appointed vice president of engineering for Canadair Ltd., a Canadian aircraft manufacturer owned by the General Dynamics Corporation. After serving as a consultant for General Dynamics in Washington, D.C., Ken Ebel retired.

Mrs. Ebel died in 1968. He later married Ms. Helene H. Topping

Walter Kenneth Ebel died at the Greater Baltimore Medical Center, Baltimnore, 12 July 1972.

© 2019, Bryan R. Swopes

24 June 1939

Boeing 314 NC18603, Yankee Clipper (Harris and Ewing)
Boeing 314 NC18603, Yankee Clipper (Harris & Ewing)

24 June 1939: The Pan American Airways System began scheduled air service from the United States to Britain. The Boeing 314 Yankee Clipper, NC18603, made the first flight from Port Washington, New York, departing at 8:21 a.m. It made intermediate stops at Shediac, New Brunswick, and Botwood, Newfoundland, where fog delayed the flying boat until 12:49 p.m., 28 June. Continuing across the Atlantic, Yankee Clipper made another stop at Foynes, Ireland, and finally arrived at Southampton at 7:25 p.m. that evening.

The largest airplane of the time, the Pan American Clipper flying boat could carry 77 passengers in “one class” luxury, with a ticket priced at $675—that’s in 1939 dollars. ($15,610.71 in 2025) Uniformed waiters served five and six course meals on silver service. Seats could be folded down into beds.

The flight deck of a Boeing 314. At the left, standing, is the airliner's navigator. Beyond him are the captain (left) and co-pilot. On the right side of the cabin are the radio operator and flight engineer. (Unattributed)
The flight deck of a Boeing 314. At the left, standing, is the airliner’s navigator. Beyond him are the captain (left) and co-pilot. On the right side of the cabin are the radio operator and flight engineer. (Unattributed)

The Boeing Model 314 was a large four-engine, high-wing monoplane flying boat designed and built by the Boeing Airplane Company to take off and land on water. It had a crew of 10. The wings and engine nacelles had been designed for Boeing XB-15 heavy bomber. It was 106 feet (32.309 meters) long with a wingspan of 152 feet (46.330 meters). It had a maximum take off weight of 82,500 pounds (37,421 kilograms).

The Boeing 314 was powered by four air-cooled, supercharged, 2,603.737-cubic-inch-displacement (42.668 liter) Wright Aeronautical Division Cyclone 14 GR2600A2, two-row, 14-cylinder radial engines with a compression ratio of 7.1:1. They were rated at 1,200 horsepower at 2,100 r.p.m., and 1,550 horsepower at 2,400 r.p.m. for takeoff, burning 91/96 octane gasoline. These engines (also commonly called “Twin Cyclone”) drove three-bladed Hamilton Standard Hydromatic full-feathering constant-speed propellers with a diameter of 14 feet (4.267 meters) through a 16:9 gear reduction. The GR2600A2 was 5 feet, 2.06 inches (1.576 meters) long and 4 feet, 7 inches (1.387 meters) in diameter. It weighed 1,935 pounds (878 kilograms). The engines could be serviced in flight, with access through the wings.

Pan American Airways’ Boeing 314 NC18603, Yankee Clipper.

The Boeing 314 had a maximum speed of 199 miles per hour (320 kilometers per hour), with a  range of 3,685 miles (5,930 kilometers) at its normal cruising speed of 183 miles per hour (295 kilometers per hour). Its service ceiling was 13,400 feet (4,084 meters). The fuel capacity was 4,246 gallons (16,073 liters).

Boeing built six Model 314 and another six 314A flying boats for Pan American Airways and British Overseas Airways Corporation.

Yankee Clipper was destroyed 22 February 1943 at Lisbon, Portugal. A wing hit the water on landing. 24 of the 39 persons aboard were killed.

This iluustration shows the interior arrangement of the Boeing 314. (Unattributed)
This illustration shows the interior arrangement of the Boeing 314. It was published in LIFE Magazine, circa 1937. (Boeing)

© 2017, Bryan R. Swopes

Igor Ivanovich Sikorsky (25 May 1889–26 October 1972)

Igor Ivanovich Sikorsky, 1914. (Karl Karlovich Bulla)
Igor Ivanovich Sikorsky, 1914. Sikorsky is wearing the cross of the Imperial Order of St. Vladimir. (Karl Karlovich Bulla)

25 May 1889: Ігор Іванович Сікорський (Igor Ivanovich Sikorsky) was born at Kiev, Ukraine, Russian Empire, the fifth of five children of Professor Ivan Alexeevich Sikorsky and Doctor Mariya Stefanovich Sikorskaya.

15 year-old Midshipman Igor Ivanovich Sikorksky, at lower right, with his sisters Olga, Lydia and Elena, and brother Sergei, 1904. (Sikorsky, a Lockheed Martin Company)
15 year-old Midshipman Igor Ivanovich Sikorksky, Imperial Naval Academy, at lower right, with his sisters Olga, Lydia and Elena, and brother Sergei, 1904. (Sikorsky, a Lockheed Martin Company)

He studied at the Imperial Naval Academy, St. Petersburg, from 1903 until 1906, when he left to study engineering, first in Paris, and then at the Kiev Polytechnic Institute.

Airplane pilot Igor Sikorsky with a passenger. (RIA Novosti)
Pilot Igor Ivanovich Sikorsky with a passenger, circa 1914. (RIA Novosti)

Flying an airplane of his own design, the S-5, on 18 April 1911, he received a Fédération Aéronautique Internationale pilot’s license from L’Aéro-Club Imperial de Russie (Imperial Russian Aero Club).

Igor I. Sikorsky's FAI pilot's license. (Sikorsky Historical Archives)
Igor I. Sikorsky’s FAI pilot’s license. (Sikorsky Historical Archives)

He was chief aircraft engineer for Russko-Baltiisky Vagonny Zavod at St. Petersburg and continued to develop airplanes. In 1913, he flew the twin engine S-21 Le Grand, to which he added two more engines, and it became the Russky Vityaz.

Igor Sikorsky with one of his early biplanes.
Igor Sikorsky with one of his early biplanes.
Sikorsky S-21 in flight
Sikorsky’s S-21 in flight, 1913

Igor Sikorsky married Olga Fyodorovna Simkovich. They had a daughter, Tania. The couple soon divorced, however.

Compagnie Générale Transatlantique liner, SS La Lorraine, 11,146 gross tons.
Compagnie Générale Transatlantique liner, S.S. La Lorraine, 11,146 gross tons.

Following the October Revolution, Sikorsky emigrated to the United States. Departing Le Havre, France, aboard S.S. La Lorraine, he arrived at New York on 31 March 1919. With financial backing from composer and conductor Sergei Vasilievich Rachmaninoff, he founded the Sikorsky Aero Engineering Company at Long Island, New York, in 1924, and continued designing and building airplanes.

In 1924, Sikorsky married Elisabeth Semion, who was also born in Russia, in 1903. They would have four children. In 1928, he became a citizen of the United States of America.

Sikorsky S-39 amphibian NC54V (Civil Air Patrol)
Sikorsky S-39 amphibian NC54V (Civil Air Patrol)

Beginning in 1934, Sikorsky Aircraft produced the S-42 flying boat for Pan American Airways at a new plant at Stratford, Connecticut.

U.S. Navy RS-1 (Sikorsky S-41) (National Museum of Naval Aviation)
U.S. Navy RS-1 (Sikorsky S-41) (National Museum of Naval Aviation)
A Pan American Airways Sikorsky S-42, NC16742, moored at Honolulu, Territory of the Hawaiian Islands. (hawaii.gov/hawaiiaviation)
Pan American Airways Sikorsky S-42, NC16734, moored at Honolulu, Territory of the Hawaiian Islands. (hawaii.gov/hawaiiaviation)

Interested in helicopters since the age of 9, he directed his creative effort toward the development of a practical “direct-lift” aircraft. The first successful design was the Vought-Sikorsky VS-300. Using a single main rotor, the VS-300 went through a series of configurations before arriving at the single anti-torque tail rotor design, the VS-316A. This was put into production for the U.S. military as the Sikorsky R-4.

The prototype VS-300 helicopter clears the ground for the first time, 14 September 1939. Igor Sikorsky is at the controls. His right foot rests on the anti-torque pedal. (Sikorsky Historical Archives)
The prototype VS-300 helicopter clears the ground for the first time, 14 September 1939. Igor Sikorsky is at the controls. His right foot rests on the anti-torque pedal. (Sikorsky Historical Archives)
Igor Sikorsky hovers the Vought-Sikorsky VS-300. (Sikorsky, a Lockheed Martin Company)
Igor Sikorsky hovers the Vought-Sikorsky VS-300A. (Sikorsky, a Lockheed Martin Company)
On behalf of the Fédération Aéronautique Internationale, the National Aeronautic Association of the United States issued Helicopter Pilot Certificate No. 1 to Igor I. Sikorsky, 10 December 1940. (Sikorsky Historical Archives)
On behalf of the Fédération Aéronautique Internationale, the National Aeronautic Association of the United States issued Helicopter Pilot Certificate No. 1 to Igor I. Sikorsky, 10 December 1940. (Sikorsky Historical Archives)
Igor Sikorsky hovers the VS-300 before presenting it to The Henry Ford, 7 October 1943. (Photograph courtesy of Tom Fisher, The Henry Ford. Object ID: 84.1.1660.P.B.27654)
Igor Sikorsky in the cockpit of a Sikorsky S-48 (R-5) helicopter. (Smithsonian Institution National Air and Space Museum)

The company which Igor Sikorsky founded has continued as one of the world’s biggest helicopter manufacturers. Recently acquired by Lockheed Martin, Sikorsky continues to produce the UH-60-series of Blackhawk medium helicopters, the large CH-53K King Stallion, and the civil S-76D and S-92. A variant of the S-92 has been selected as the next helicopter for the U.S. presidential air fleet, the VH-92A. This helicopter is planned to be operational by 2020.

Igor Ivanovich Sikorsky died at Easton, Connecticut, 26 October 1972 at the age of 83 years.

Igor Sikorsky piloting his pontoon-equipped VS-300, 17 April 1941. (Sikorsky Historical Archives)
Igor Sikorsky piloting his pontoon-equipped VS-300, 17 April 1941. (Sikorsky Historical Archives)
s-47-4
Les Morris at the controls of the Vought-Sikorsky XR-4, 41-18874 (VS-316A), on its first flight at Stratford, Connecticut, 14 January 1942. (Sikorsky Historical Archives)
Lt. Carter Harman hovering in ground effect with Sikorsky YR-4B Hoverfly 43-28247 at Lalaghat, India, March 1944. This is the helicopter with which he made the first combat rescue, 21-25 April 1944. (U.S. Air Force)
Lt. Carter Harman hovering in ground effect with Sikorsky YR-4B Hoverfly 43-28247 at Lalaghat, India, March 1944. This is the helicopter with which he made the first combat rescue, 21-25 April 1944. (U.S. Air Force)
A Sikorsky R-5 flown by Jimmy Viner with Captain Jack Beighle, lifts a crewman from Texaco Barge No. 397, aground on Penfield Reef, 29 November 1945. (Sikorsky Historical Archive)
U.S. Army R-5 (Sikorsky S-48) flown by Jimmy Viner with Captain Jack Beighle, lifts a crewman from Texaco Barge No. 397, aground on Penfield Reef, 29 November 1945. (Sikorsky Historical Archive)
Sikorsky R-5 medevac, Korean War
U.S. Air Force H-5 (Sikorsky S-51) lifts off during the Korean War. (U.S. Air Force)
U.S. Coast Guard HOS-1 (Sikorsky S-49), with Igor Sikorsky as a passenger, over the Kill Devil Hills, North Carolina, 17 December 1947—the 44th annivesary of teh Wright Brothers first controlled, powered airplane flight. (Sikorsky Historical Archives)
U.S. Coast Guard HOS-1 (Sikorsky S-49), with Igor Sikorsky as a passenger, over the Kill Devil Hills, North Carolina, 17 December 1947—the 44th annivesary of the Wright Brothers first controlled, powered airplane flight. (Sikorsky Historical Archives)
U.S. Army YH-18A 49-2889 (Sikorsky S-52-2) (Ed Coates Collection)
U.S. Army YH-18A 49-2889 (Sikorsky S-52-2) (Ed Coates Collection)
SH-19A Air Rescue Sqd. AR.1999.026
U.S. Air Force SH-19A Chickasaw 51-3850 (Sikorsky S-55), Air Rescue Service. (U.S. Air Force)
Sikorsky H-34A-SI Choctaw (S-58) 57-1743 hovers in ground effect. Later registered as a civilian aircraft, N47246). (U.S. Army)
U.S. Army H-34A-SI Choctaw (Sikorsky S-58) 57-1743 hovers in ground effect. Later registered as a civilian aircraft, N47246). (U.S. Army)
Sikorsky CH-37 Mojave heavy-lift helicopter
U.S. Marine Corps CH-37 Mojave (Sikorsky S-56) heavy-lift helicopter
A U.S. Navy Sikorsky SH-3A Sea King (S-61), Bu. No. 149867, near Oahu, Hawaiian Islands, 5 April 1976. (PH2 (AC) Westhusing, U.S. Navy)
U.S. Navy SH-3A Sea King (Sikorsky S-61), Bu. No. 149867, near Oahu, Hawaiian Islands, 5 April 1976. (PH2 (AC) Westhusing, U.S. Navy)
A U.S. Coast Guard HH-52A Seaguard (Sikorsky Model 62). (United States Coast Guard)
A Sikorsky HH-3E Jolly Green Giant (66-13290) ot the 37th ARRS, hovering in ground effect at Da Nang, 1968. (U.S. Air Force)
U.S. Air Force HH-3E Jolly Green Giant (Sikorsky S-61R), 66-13290, of the 37th ARRS, hovering in ground effect at Da Nang, 1968. (U.S. Air Force)
A U.S. Air Force Sikorsky HH-53C Super Jolly Green Giant hovers to hoist a pararescueman with one downed pilot, while a second waits on the ground, 16 June 1967. The blade tip vortices are visible because of the high humidity. (National Archives at College Park)
Sikorsky CH-54A Tarhe 68-18448, Nevada National Guard, 16 Nober 1989. (Mike Freer/Wikipedia)
U.S. Army CH-54A Tarhe 68-18448 (Sikorsky S-64) heavy-lift helicopter, Nevada National Guard, 16 November 1989. (Mike Freer/Wikipedia)
Sikorsky MH-53M Pave Low IV, 68-8424, prepares for its last combat mission, Iraq, 27 September 2008. (A1C Jason Epley, U.S. Air Force)
U.S. Air Force MH-53M Pave Low IV 68-8424 (Sikorsky S-65), prepares for its last combat mission, Iraq, 27 September 2008. (A1C Jason Epley, U.S. Air Force)
U.S. Army Special Forces soldiers dismount a Sikorsky UH-60 Blackhawk, Zabul Province, Afghanistan, 21 January 2010. (Detail from photograph by Staff Sergeant Aubree Clute, U.S. Army)
Sikorsky HH-60G Pave Hawk 89-26212. (U.S. Air Force)
U.S. Air Force HH-60G Pave Hawk (Sikorsky S-70) 89-26212, Kunar Province, Afghanistan. (Captain Erick Saks, U.S. Air Force)
British Airways' Sikorsky S-61N G-BEON, 1982. ( )
British Airways’ Sikorsky S-61N Sea King G-BEON, 1982.
An Erickson Air-Crane, Inc. Sikorsky S-64 Skycrane drops water on a forest fire. (Sikorsky Archives)
An Erickson Air-Crane, Inc., Sikorsky S-64 Skycrane drops water on a forest fire. (Sikorsky Archives)
1280px-040327-pb-firehawk-17-16
A Los Angeles County Fire Department Sikorsky S-70A Firehawk, N160LA, during a rescue near Palmdale, California, 27 March 2004. (Alan Radecki/Wikipedia)
A Queen's Helicopter Flight Sikorsky S-76C, s/n 760753, G-XXEB (Russell Lee/Wikipedia)
A Queen’s Helicopter Flight Sikorsky S-76C, s/n 760753, G-XXEB (Russell Lee/Wikipedia)
Cougar Helicopters' Sikorsky S-92A C-GKKN landing at Ilulissat Airport, Greenland, 5 August 2010. (Algkalv/Wikipedia)
Cougar Helicopters’ Sikorsky S-92A C-GKKN landing at Ilulissat Airport, Greenland, 5 August 2010. (Algkalv/Wikipedia)
Sikorsky CH-53K King Stallion (Sikorsky, A Lockheed Martin Company)
The prototype Sikorsky CH-53K King Stallion (Sikorsky, A Lockheed Martin Company)

© 2017, Bryan R. Swopes

19 May 1949

Martin JRM-3 Mars, Bu.No. 76822, Marshall Mars. (U.S. Navy)
Martin JRM-3 Mars, Bu. No. 76822, Marshall Mars. (U.S. Navy)

19 May 1949: Martin JRM-3 Mars, Marshall Mars, United States Navy Bureau of Aeronautics serial number (Bu. No.) 76822 flew from the Alameda Naval Air Station on the east shore of San Francisco Bay, to San Diego Bay, a distance of approximately 450 miles (725 kilometers). On board, in addition to the flight crew of 7, were 301 passengers.

Martin JRM-3 Marshall Mars with its passengers. (NOAA)

The Associated Press wire service reported the story:

NAVY’S BIG FLYING BOAT MARSHALL MARS CARRIES 301 PERSONS

SAN FRANCISCO, May 19—(AP)—The Navy’s big flying boat Marshall Mars carried a record load of 301 passengers—plus seven crewmen—on a flight to San Diego today.

It had never carried more than 269 passengers before.

The 1:52 p.m. takeoff, from the naval air station at Alameda, across the bay, was uneventful.

Today’s passengers are personnel of Air Group 5, Alameda Naval Air Station, who are being transferred to San Diego. Mattresses on the floor were provided for men unable to find seats.

Wilmington Morning Star, Friday, 20 May 1949, Page 1, Column 4.

Four Martin JRM-3 Mars flying boats in formation. (U.S. Navy)
Four Martin JRM-3 Mars flying boats in formation. In the foreground is Philippine Mars, Bu. No. 76820. The second airplane is Marianas Mars, Bu. No. 76821. (U.S. Navy)

The Martin JRM Mars was a large four-engine flying boat transport built by the Glenn L. Martin Company for the U. S. Navy. Only five were built, four designated JRM-1, with the last one being a JRM-2. Each airplane was given an individual name derived from the names of island chains in the Pacific Ocean: Marianas MarsHawaii MarsPhilippine MarsMarshall Mars and Caroline Mars. These airplanes were used to transport personnel and cargo between the West Coast of the United States and the Hawaiian Islands. All were upgraded to JRM-3.

The Martin JRM-3 Mars had a normal crew of 4, with accommodations for a relief crew. It was designed to carry 133 combat troops or 32,000 pounds (14,515 kilograms) of cargo. It was 120 feet, 3 inches (36.652 meters) long with a wingspan of 200 feet (60.960 meters) and height of 38 feet, 5 inches (11.709 meters). The flying boat had an empty weight of 80,701 pounds (36,605.4 kilograms). The maximum takeoff weight (MTOW) was 165,000 pounds (74,842.7 kilograms).

A NASA publication states, “A zero-lift drag coefficient of 0.0233 and a maximum lift-drag ratio of 16.4 made the JRM the most aerodynamically efficient of any of of the flying boats. . . .”

The Martin Mars was powered by four air-cooled, supercharged, direct-fuel-injected, 3,347.662-cubic-inch-displacement (54.858 liter) Wright Aeronautical Division R-3350-24WA (Cyclone 18 825C18BD1) (also known as the Duplex-Cyclone), a two-row 18-cylinder radial engines with a compression ratio of 6.70:1 and water/alcohol injection. This engine has a normal power rating of 2,000 horsepower at 2,400 r.p.m at 5,500 feet (1,676 meters) and 1,800 horsepower at 2,400 r.p.m. at 15,000 feet (4,572 meters). The engine’s takeoff power rating is 2,500 horsepower at 2,900 r.p.m. 100/130 octane aviation gasoline was required. The engines drove four-bladed 16 foot, 8 inch (5.080 meter) Curtiss Electric variable-pitch propellers through a 0.375:1 gear reduction. (After modification to the JRM-3, the propellers on the inboard engines were reversible.) The R-3350-24WA is 6 feet, 8.58 inches (2.047 meters) long, and 4 feet, 6.13 inches (1.375 meters) in diameter. Its dry weight is 2,822 pounds (1,280 kilograms).

The JRM-3 had a cruise speed of 135 knots (155 miles per hour/250 kilometers per hour) and a maximum speed of 211 knots (243 miles per hour/391 kilometers per hour) at 15,600 feet (4,755 meters). The service ceiling was 19,700 feet (6,005 meters) and its range was 3,790 nautical miles (4,361 miles per hour/7,019 kilometers) at 135 knots.

On 5 April 1950, Marshall Mars had an engine fire and made an emergency landing off Diamond Head, Hawaii. The crew was rescued but the airplane exploded and sank. The wreck was discovered on the sea floor in August 2004.

The remaining airplanes were later converted to fire fighting airplanes in Canada. Only two remain.

Martin JRM-3 Mars Bu. No. 76822, Marshall Mires, burning off Diamond Head, Oahu, Hawaiian Islands, 5 April 1950. (U.S. Navy)
Martin JRM-3 Mars, Bu. No. 76822, Marshall Mars, burning off Diamond Head, Oahu, Territory of the Hawaiian Islands, 5 April 1950. (U.S. Navy)

© 2020, Bryan R. Swopes

12 April 1918

Malcolm and Allan Loughead in cockpit of their F-1 flying boat, 1918. (San Diego Air & Space Museum)

12 April  1918: Allan and Malcolm Loughead, owners of the Loughead Aircraft Manufacturing Company of Santa Barbara, California, set speed and distance records as they flew their twin-engine, ten-place F-1 flying boat from Santa Barbara to San Diego. The F-1 traveled 211 miles (340 kilometers) in 3 hours, 1 minute.¹

The F-1 took off from the waters off West Beach at Santa Barbara at 9:21 a.m., passed Point Fermin at 10:40 a.m., Oceanside at 11:55 a.m., and arrived at North Island at 12:23 p.m.² The airplane was flown by the two Loughead Brothers and carried two passengers.

The Southern California shorline from Santa Barbara, at the upper left, to San Diego, at the lower right. (Google Maps)

GREAT SEAPLANE MAKES RECORD ON FLIGHT

     SAN DIEGO, April 12.—The big seaplane F-1, piloted by Malcolm Loughead and carrying three passengers, arrived here at 12:23 this afternoon.

     The F-1 left Santa Barbara at 9:21 this morning and the estimated distance of 190 miles between that city and San Diego was therefore covered in exactly three hours and two minutes, a speed of approximately 63 1-3 miles an hour. The big seaplane was first sighted over Point Loma and within a few minutes alighted on the surface of San Diego Bay a short distance from the United States army aviation station at North Island. At 12:23 the seaplane reached the North Island landing and was hauled ashore by army men in waiting. According to Pilot Loughead, the trip was made without incident, although during the latter part of the trip headwinds were met with which retarded the speed of the aircraft.

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     Three hours and two minutes by air flight to San Diego from Santa Barbara—that’s the record established today by Allan and Malcolm Loughead, in their big hydroplane, F-1, carrying as passengers Alfred Holt and Carl Christopherson, employees of the Loughead Aeroplane Manufacturing Company.

     The distance of 190 miles, by airplane, was made without mishap. The start from Santa Barbara gathered quite a group of citizens, among them being a number of stockholders in the Loughead company, and thousands would have been there to witness the notable start had it been known at what hour the flight would start.

     During the morning the Lougheads received a dispatch from government officials at the aviation headquarters on North Island, San Diego, informing them that air and ocean conditions were perfect all the way south, and asking that the flight be made today.

     The Lougheads were even at that moment getting ready for the departure, and arrangements were hastened. The bay was ruffled by a breeze, and the combers sparkled in the warm sunlight, as the hydroplane motors were started, and the big fans began to whirr. There were hasty farewells, and every man waved his hat and every woman present shook a kerchief, while the cheers broke forth from all as the big plane sped down the ways, and went skidding into the sea.

     At the wheels were Allan and Malcolm Loughead, while Christopherson and Holt occupied places in the passengers’ quarters at the head of the big plane. The machine was guided in a half circle, taking a southwesterly course at first, until beyond the pleasure pier, where it rose from the bosom of the sea, and rapidly ascended to an altitude of about 500 feet, when it took a southeasterly course, and heading down the channel toward Oxnard.

     It was a perfect get-away, and no bird ever took to the air more gracefully than the big plane rose above the sea and soared away, easily, the very hypothesis of graceful motion, and the speed at which it was travelling soon took it out of sight to the south.

     From Ventura and Hueneme the flight was witnessed by a large number of citizens, and at Point Fermin, near San Pedro, the passing of the plane attracted great interest. In fact, all the way south, great crowds watched eagerly and it was a continuous ovation that greeted the airmen from the land.

     At San Diego the fliers were met by a big crowd, and their stay in the southern city is being made one prolonged reception. From many points along the coast today telephone and telegraph messages have flashed, reporting the passing of the machine, whose eventful trip is the biggest sensation of the day in aviation circles.

     It is stated that the flight establishes a long distance record for a passenger-carrying hydroplane. The plane will be tested out by the government aviation officials, and it is expected that within a very few days the announcement will be made of a contract awarded the Loughead Brothers by the government for other machines.

     Experts who have examined the F-1 state that it is perfectly built, and the finest machine of its class afloat.     

The Santa Barbara Daily News and the Independent, Friday, 12 April 1918, Page 1, Column 6

Loughead Aircraft Manufacturing Company F-1. (Lockheed Martin).

Designed by friend and employee John Knudson (“Jack”) Northrop, and built in a garage on State Street, the F-1 was launched on a wooden ramp at West Beach.

The airplane was intended for the U.S. Navy, but the end of World War I ended the requirement for new airplanes.

The Loughead F-1 was a twin-engine, three-bay biplane flying boat operated by a crew of 2. It could carry 8–10 passengers. The airplane was 35 feet (10.668 meters) long. The span of the upper wing was 74 feet (22.555 meters) and the lower wing was 47 feet (14.326 meters). The height was 12 feet (3.658 meters). The F-1 had an empty weight of 4,200 pounds (1,905 kilograms) and gross weight of 7,300 pounds (3,311 kilograms).

Loughead F-1 at Santa Barbara, 1918. (San Diego Air and Space Museum)
Loughead F-1 at Santa Barbara, 1918. (San Diego Air & Space Museum)

The F-1 was powered by two right-hand tractor, water-cooled, normally-aspirated 909.22-cubic-inch-displacement (14.899 liters) Hall-Scott A-5-engines. These were inline six-cylinder single-overhead-camshaft (SOHC) engines with a compression ratio of 4.6:1. It was rated at 150 horsepower and produced 165 horsepower at 1,475 r.p.m. The engines were mounted on steel struts between the upper and lower wings. The engines were direct-drive and turned two-bladed, fixed pitch propellers with a diameter of 8 feet, 8 inches (2.642 meters). The Hall-Scott A-5-a was 5 feet, 2.5 inches (1.588 meters) long, 2 feet, 0 inches (0.610 meters) wide and 3 feet, 7.875 inches (1.114 meters) high. It weighed 595 pounds (270 kilograms).

The F-1 had a cruise speed of 70 miles per hour (113 kilometers per hour) and maximum speed of 84 miles per hour (135 kilometers per hour).

The F-1 was converted to a land plane with tricycle undercarriage and redesignated F-1A. During an attempted transcontinental flight, it twice suffered engine failure and was damaged. Reconfigured as a flying boat, the airplane was used for sight-seeing before being sold. It was abandoned on a beach at Santa Catalina Island, off the coast of Southern California, and was eventually destroyed.

Loughead F-1, 1918. (San Diego Air & Space Museum)

The Loughead Aircraft Manufacturing Company would go on to become one of the world’s leading aerospace corporations.

¹ The certifying source for this “record” is not known. The distance flown and elapsed time for the flight cited here are from Wikipedia. The Great Circle distance from today’s Santa Barbara Airport (SBA) to NAS North Island (NZY) is 193 statute miles (311 kilometers). However, contemporary news reports suggest that the Loughead brothers flew the F-1 along California’s southern coastline, rather than making a direct flight across the Santa Barbara Channel, Santa Monica Bay, the Catalina Channel, and on to San Diego Bay. At the time of this flight, the governing body for aviation in the United States was the Aero Club of America, while official flight records were certified by the Fédération Aéronautique Internationale, which was based in France. The ACA ceased to exist in 1923, replaced by today’s National Aeronautic Association. The FAI online records database list only two world records set in 1918, both altitude records set by Major Rudolph Schroeder, 18 September 1918, at Dayton, Ohio.

² The Los Angeles Times, the Oakland Tribune and the San Bernardino Daily Sun state that the time of the takeoff was 9:23 a.m. The Tribune cites the arrival time as 12:24 p.m., while the Daily Sun reported the time as both 12:32 and 12:24. Various newspapers reported the distance flown by the F-1 as 190 miles (306 kilometers), while The Salt Lake Herald-Republican-Telegram printed that it was 200 miles (322 kilometers).

© 2023, Bryan R. Swopes