Martin JRM Mars

Martin JRM Mars Story

World War II proved the swan song of airships, with larger aircraft gaining ship-like fuselages and high-mounted wings for efficient water take-off and landing. While slow and bulky beasts, these vehicles demonstrate excellent inherent operational range, being able to reach any runway with sufficient water clearance for these aircraft to take off or land.

The Glenn L. Martin Company was founded in 1912, when it was producing the largest Allied airships of the war, when it launched its "JRM Mars" model line - an evolution of the "PBM Mariner" itself, which was launched in 1939 . The JRM Mars was commissioned by the US Navy for use as a surface patrol bomber and received the development designation "XPB2M-2 Mars" (company name "Model 170"). The first flight was on June 23, 1942.

The XPB2M-1 Mars prototype retains the basic form and function of the previous PBM Mariner series, including its deep boat-like fuselage, widened wings and twin vertical stabilizers - it is essentially an oversized version of the Mariner4 x Wright R-3350-8 radial piston engine powers the Power. Mars was completed in November 1941, although a fire in one of its four engines caused enough damage to delay its maiden flight until June the following year. The necessary evaluations were carried out before the aircraft was officially accepted by the U.S.

Navy on November 30, 1943.

After Pearl Harbor on December 7, 1941, the United States has been in a state of total war since January 1942. As expected, warfare developed at an ever-increasing rate, and with it came different techniques and theories for all aspects of warfare.

The idea of ??a large flying patrol boat bomber has now been lost as that role has been replaced by other proven multi-role platforms whose ranges have greatly improved since the war began. So the US Navy doesn't really need a new Martin patrol bomber, but considering the design is enough to order 20. Her role was slightly modified for use as a ground transport and was given the new development designation "XPB2M-1R".

The original Martin prototype was subsequently refitted in December 1943 as a modification with no predetermined armament, an elongated fuselage and a more traditional single-rudder fin. The fuselage is reinforced for cargo transport and various devices have been added to facilitate the transport of cargo in and out of the aircraft. Power is provided by 4 Wright R-3350-24WA Cyclone Radial.

The final designation for the production form was "JRM-1 Mars" (Martin "Model 170A").

The entire war of 1944 worked in the Allies' favor as work intensified to complete the original US Navy order, leading to the fall of Germany in May 1945 and the fall of the Empire of Japan in August 1945. At this point, the first JRM was already in the hands of the US Navy (June 1945), although several other airframes were still awaiting completion on the Martin assembly line. With wartime demands almost over, the Navy cut the initial 20-person contract and ended up procuring just six ships in total.

The planes were given entirely different personal names - all based on the Pacific islands - starting with the original "Hawaii Mars." This was followed by the "Mariana Mars", "Philippine Mars", "Marshall Mars", "Caroline Mars" and another "Hawaii Mars" (the original Hawaiian Mars was lost in an accident in 1942, making replacement aircraft possible). so named). Deliveries of the Mars plane ended in 1947.

Caroline Mars became the last Mars airframe to be completed by Martin and was given the new principal designation "JRM-2" as it was powered by 4 Pratt & Whitney R4360-4T radial engines with a total of 3,000 hp each equipped with four-blade propeller assembly.

From the outside, the Mars Aircraft series was a typical airship design at the time. The hull manages a deep hull for the required water landings. The flight deck is mounted high, providing excellent visibility for the nose and two engine pairings along the leading edge of the wing. The wings are straight in their general form, with curved tips, and are mounted high along the fuselage spine.

The aircraft is powered by four radial piston engines through separate nacelles, with two engines per wing. A twin strut pontoon is also installed on each wing to support the components on the water and prevent the aircraft from tipping over.

The fuselage tapers in the usual way at the empennage, a raised fin attached to the horizontal plane set on the high, curved rudder. Dimensions include a length of 117 feet, a wingspan of 200 feet and a height of 38 feet 5 inches. The total wing area is 3,686 square feet.

Internal volume allows the aircraft to carry up to 32,000 pounds of cargo, including 133 infantry or 7 light vehicles. In a medical evacuation mission, Mars was able to transport 84 wounded and 25 medical personnel. The curb weight is 34,280 lbs and the maximum takeoff weight is 74,800 lbs. Top speed is around 220 mph, cruising speed is 190 mph, range is up to 5,000 miles, and the operating cap is 14,600 feet.

Caroline Mars is known for setting the world record for passenger air passenger on March 4, 1949, when it transported 269 people from San Diego, California, to Alameda, California.

The original four JRM-1s were eventually upgraded to the new "JRM-3" standard, with their engines replaced with four Wright R3350-24WA radial engines, 2,400 hp each. The inboard engine now deploys a reversible pitch unit for more precise control.

With the end of the war, the remaining Mars aircraft continued to serve as a transport service in the U.S. Navy until it was retired from active duty around 1956. In 1959, four aircraft were purchased by a Canadian fire company. Marshall Mars disappeared when captured on April 5, 1950 off the coast of Honolulu, Hawaii, leaving only four airworthy Martian planes. On June 23, 1961, Maranas Mars followed, crashing while fighting a fire in British Columbia, killing all four crew members.

Caroline Mars was eventually lost by Typhoon Freda on October 12, 1962. The remaining two -- the second Hawaiian Mars and the Philippine Mars -- carry the torches.

The remaining aircraft continued on firefighting duties until 2003, when their owners offloaded the models to another Canadian firefighting company. The Philippine Mars is now destined for permanent display at the Naval Aviation Museum in Pensacola, Florida, making the second Hawaiian Mars the world's only airworthy Mars aircraft.

Specification

Basic

Production

Roles

Dimensions

Weight

Performance

Performance

Armor

Changes