Buy This 9,600-HP Radial-Engined Firefighting Seaplane From WWII for $5M

The Martin JRM-3 Mars is offered for sale by Platinum Fighter Sales for $5 million, and yes, it's ready-to-fly. The plane's life began originally in the lead-up to World War II, when the US Navy commissioned The Martin Company (now carrying its name on in Lockheed Martin) to build a massive flying boat for use as a patrol bomber. (Flying boats land on their bellies, as opposed to floatplanes, which use pontoons.) By the time the first development prototype (known as the XPB2M-1, seen below) initially flew in November 1941, patrol bombers were considered obsolete; nonetheless, the Navy ordered 20 JRMs, but changed its purpose to that of a long-range transport plane. As the war wound down the Navy canceled most of its order and only ended up purchasing six of the massive aircraft. The first of these entered service in mid-1945 and as a result, never saw much action in WWII, instead serving as cargo and troop carriers for post-war Pacific operations. Despite its low production numbers and limited use, the JRM still represented the peak of Allied flying boats in WWII, with a 200-foot wingspan, four 2,400 HP radial engines, and an absolutely absurd in-its-era range of 4,900 miles (for comparison, the B-29 Superfortress that saw heavy use in WWII had a range of 3,250 miles).

Of the seven built (six production, and one test craft), the test plane was scrapped at the end of the war, and another production craft was lost almost immediately in a crash in 1945. The remaining five saw service after WWII in a variety of jobs, including troop-carrying service (for which the JRM captured the at-the-time passenger record in 1950, with 301 passengers on a single flight). By 1956 there were four left parked at the US Naval facility in Alameda, CA, as they had been made obsolete by more modern post-war aircraft and the continued construction of the long runways needed to land them on. In 1959, they were saved from scrap by a Canadian company that purchased all four and converted them to firefighting tankers.

The years whittled down the fleet further through either neglect, typhoon damage, or crashes until there was only one flightworthy example remaining. That one plane, the Hawaii Mars II, is the one for sale now. It served as a tanker until 2015, with a 7,200-gallon water capacity that it could refill in a single 20-second water skimming run. The Hawaii Mars II is powered now by a set of four Wright R-3350 Duplex-Cyclone 18-cylinder radial engines, producing 2,400 HP each, keeping it aloft. Its last flight was an exhibition one in 2016, and it is sold as-is where-is, so expect to need to do a thorough once-over before taking to the skies in it. And yes, I admit that overall it might be a little more finicky a personal plane than a HondaJet with a combined 72 pistons to keep an eye on and an operational history spanning 76 years, but I'd still argue it's worth it.