The large, four-engined cargo transport seaplanes were designed and built for the U.S. Navy during the World War II era and were the largest Allied flying boats to enter (albeit limited) production, delivered to the US Navy between 1945 and 1948.
The impressive planes were each christened with proper names, perhaps as a nod to their nautical roots. The prototype plane was named The Old Lady; production planes were named as follows: Hawaii Mars, Philippine Mars, Marianas Mars, Marshall Mars, Hawaii Mars II (named subsequent to the destruction of the original Hawaii Mars) and finally, Caroline Mars.
Caroline Mars set a new world passenger load record by carrying 269 people from San Diego to Alameda, California on March 4, 1949. On April 5, 1950, Marshall Mars was lost near Hawaii when an engine fire consumed the airplane after her crew had evacuated. The remaining four planes flew record amounts of naval cargo on the San Francisco-Honolulu route until 1956, when the entire fleet of massive flying boats were beached at NAS Alameda. In 1959 the four planes were scheduled to be sold for scrap, but were instead purchased by Forest Industries Flying Tankers along with a large stock of spare parts who set about converting the cargo planes for their new role as water bombers.
The first two planes to be converted, Marianas Mars and Caroline Mars both met with untimely ends. Marianas Mars crashed near Northwest Bay, British Columbia in 1961 during firefighting operations with the loss of her crew and just over a year later the Caroline Mars was destroyed by Typhoon Freda while parked onshore.
Due to the loss of their sister ships, the Hawaii Mars II and Philippine Mars had their conversions to water bombers accelerated and entered fire bombing service in 1963. The conversion of these planes involved the installation of a water tank in the cargo bay and retractable pick-up scoops to allow the uploading of water while the aircraft was taxiing. The scoops allowed an astonishing 30 tons of water to be taken onboard in just 22 seconds. The aircraft carried 7,200 gallons of water and each drop could saturate an area of up to 4 acres.
Coulson Flying Tankers of British Columbia, Canada has owned the two planes since 2007. The Philippine Mars had been undergoing extensive renovation and maintenance since 2008, but in a surprising move Coulson Flying Tankers, citing the plane’s disuse over the past five years, announced that the Philippine Mars would be retired and flown to the National Naval Aviation Museum to become a static exhibit. It is anticipated the the plane will be available for viewing by the public sometime this summer, restored to the original paint scheme and markings she wore during her service with the US Navy.
Hawaii Mars II remains in use and in active service traveling to fire hot spots along the entire west coast of Canada, the United States and Mexico.