Martin JRM Mars Flying Boat

https://en.wikipedia.org/wiki/Martin_JRM_Mars

The Martin JRM Mars is a large, four-engined cargo transport seaplane originally
designed and built in limited numbers for the U.S. Navy during the World War II
era. It was the largest Allied flying boat to enter production, although only
seven were built. The United States Navy contracted the development of the
XPB2M-1 Mars in 1938 as a long range ocean patrol flying boat, which later
entered production as the JRM Mars long range transport.

Four of the surviving aircraft were later converted for civilian use to
firefighting water bombers. One example of the aircraft still remains in limited
service based out of Sproat Lake just outside of Port Alberni, British Columbia.

The Glenn L. Martin Company scaled up their PBM Mariner patrol bomber design to
produce the prototype XPB2M-1 Mars. The XPB2M-1 was launched on 8 November 1941.
After a delay caused by an engine fire during ground runs, the aircraft first
flew on 23 June 1942. After flight tests with the XPB2M between 1942 and 1943,
she was passed on to the Navy. The original patrol bomber concept was considered
obsolete by this time, and the Mars was converted into a transport aircraft
designated the XPB2M-1R. The Navy was satisfied with the performance, and
ordered 20 of the modified JRM-1 Mars.[1] The first, named Hawaii Mars, was
delivered in June 1945, but with the end of World War II the Navy scaled back
their order, buying only the five aircraft which were then on the production
line. Though the original Hawaii Mars was lost in an accident on Chesapeake Bay
a few weeks after it first flew, the other five Mars were completed, and the
last delivered in 1947.

Role Flying boat
National origin United States
Manufacturer Glenn L. Martin Company
First flight 23 June 1942
Introduction 30 November 1943
Retired 1956 (USN)
Status Limited use
Primary users United States Navy
Coulson Flying Tankers Inc.
Produced 1945–1948
Number built 7

U.S. Navy service

Named the Marianas Mars, Philippine Mars, Marshall Mars, Caroline Mars, and a
second Hawaii Mars, the five production Mars aircraft entered service ferrying
cargo to Hawaii and the Pacific Islands. The last production airplane (the
Caroline Mars) was designated JRM-2, powered by 3,000 hp (2,200 kW) Pratt &
Whitney R-4360 engines, and featured a higher maximum weight and other
improvements. On 4 March 1949, the Caroline Mars set a new world passenger load
record by carrying 269 people from San Diego to Alameda, CA.[3] On 5 April 1950,
the Marshall Mars was lost near Hawaii when an engine fire consumed the airplane
after her crew had evacuated. The remaining "Big Four" flew record amounts of
Naval cargo on the San Francisco-Honolulu route efficiently until 1956, when
they were beached at NAS Alameda.

In 1959, the remaining Mars aircraft were to be sold for scrap, but a Canadian
company, Forest Industries Flying Tankers (FIFT), was formed and bid for the
four aircraft and a large spares inventory. The company represented a consortium
of British Columbia forest companies, and the bid was accepted and the sale
completed in December 1959. The four aircraft were flown to Fairey Aviation at
Victoria, British Columbia, for conversion into water bombers. The conversion
involved the installation of a tank in the cargo bay and retractable pick-up
scoops to allow uploading of water while the aircraft was taxiing. The scoops
allowed 30 tons of water to be taken on board in 22 seconds. Later some of the
hull fuel tanks were replaced with water tanks.

Specifications (JRM-3 Mars)

General characteristics
Crew: four (with accommodations for a second relief crew)
Capacity: JRM Mars - 133 troops, or 84 litter patients and 25 attendants or
32,000 lb (15,000 kg) payload, including up to seven Willys MB jeeps
Water/foam load: Mars waterbomber - 60,000 lb (27,000 kg)
Length: 117 ft 3 in (35.74 m)
Wingspan: 200 ft 0 in (60.96 m)
Width: 13 ft 6 in (4.11 m) Hull beam
Height: 38 ft 5 in (11.71 m) afloat, 48 ft (15 m) beached
Hull draught: 5 ft 6 in (1.68 m)
Wing area: 3,686 sq ft (342.4 m2)
Empty weight: 75,573 lb (34,279 kg)
Gross weight: 90,000 lb (40,823 kg)
Max takeoff weight: 165,000 lb (74,843 kg)
Fuel capacity: Hawaii Mars: 6,485 US gal (24,550 l; 5,400 imp gal) Philippine
Mars: 13,200 US gal (50,000 l; 11,000 imp gal)
Powerplant: 4 × Wright R-3350 Duplex-Cyclone 18-cylinder radial engines, 2,500
hp (1,900 kW) each
Propellers: 4-bladed Curtiss Electric, 15 ft 2 in (4.62 m) diameter
variable-pitch propellers

Performance
Maximum speed: 221 mph (356 km/h; 192 kn)
Cruise speed: 190 mph (165 kn; 306 km/h)
Range: 4,948 mi; 7,964 km (4,300 nmi)
Service ceiling: 14,600 ft (4,450 m)
Drop speed: 138 mph (120 kn; 222 km/h)
Landing approach speed: 115 mph (100 kn; 185 km/h)
Touchdown speed: 92 mph (80 kn; 148 km/h)
Fuel consumption (cruise): 420 US gal (1,600 l; 350 imp gal) per hour
Fuel consumption (operations): 780 US gal (3,000 l; 650 imp gal) per hour
Operations duration (normal): 5 1/2 hours
Area covered, single drop: 3 to 4 acres (1.2 to 1.6 ha)
Drop height: 150 to 200 ft (46 to 61 m)
Full water tank load: 7,200 US gal (27,000 l; 6,000 imp gal)







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