Lockheed P-2H Neptune aircraft maintenance @ Hawkins & Powers in Greybull

This former military maritime patrol aircraft was converted to an aerial tanker for firefighting work - the aircraft can carry 2,400 gal (9,084 l) of retardant. Tanker 139 retained the long tail cone that used to house the MAD (Magnetic Anomaly Detection) sensors.
Powered by 2 Wright R-3350-32W radial and 2 J-34 jet-engines which could operate with the avgas fuel.
A major component to forest firefighting are Aerial assets dumping water from the sky, and firefighters working on the ground to create " firebreaks''. Which is exactly what it sounds like a break between the fire and its fuel. Crews cut out a border of vegetation between the fire and surrounding land helping to contain the fire and prevent it from spreading.
Unfortunately, aerial water drops, and firebreaks aren’t enough when combating large scale fires. So, here's where that "red stuff" comes in. Fire retardant we use is called PHOSCHEK, and it is made up of primarily ammonium polyphosphate, water, fertilizer type salts, a coloring agent, corrosion inhibitors, and flow conditioners. It's a long-term fire retardant which means it can be sprayed on an area and unless it gets washed away by a rainstorm it'll stick around for months.
How does fire retardant work?
Another thing to understand is that the fire retardant isn't dropped directly on the fire, in reality it's dropped just outside of it to create a containment perimeter. PHOS-CHEK retardants work in three ways removing heat, coating the surface (so the fuel can't find oxygen), or by diluting the air near the fire. The retardants react with wildland fuels altering their route of decomposition in a fire so that they do not support flaming or glowing combustion. The rate of flame spread is reduced and can be dramatically decreased while a slow burning is allowed. The reddish color serves as a visual aid for pilots and firefighters on the ground. After a few days of exposure to direct sunlight, the color will fade and eventually disappear.
Development of a new land-based patrol bomber began early in World War II, with design work starting at Lockheed's Vega subsidiary as a private venture on 6 December 1941. At first, the new design was considered a low priority compared to other aircraft in development at the time, with Vega also developing and producing the PV-2 Harpoon patrol bomber. On 19 February 1943, the U.S. Navy signed a letter of intent for two prototype XP2Vs, which was confirmed by a formal contract on 4 April 1944 with a further 15 aircraft being ordered 10 days later.[3] It was not until 1944 that the program went into full swing. A major factor in the design was ease of manufacture and maintenance, and this may have been a major factor in the type's long life and worldwide success. The first aircraft flew in May 1945. Production began in 1946, and the aircraft was accepted into service in 1947. Potential use as a bomber led to successful launches from aircraft carriers.
Beginning with the P2V-5F model, the Neptune became one of the first operational aircraft fitted with both piston and jet engines. The Convair B-36, several Boeing C-97 Stratofreighter, Fairchild C-123 Provider, North American AJ Savage, and Avro Shackleton aircraft were also so equipped. To save weight and complexity of two separate fuel systems, the Westinghouse J34 jet engines on P2Vs burned the 115-145 Avgas fuel of the piston engines, instead of jet fuel. The jet pods were fitted with intake doors that remained closed when the J-34s were not running. This prevented windmilling, allowing for economical piston-engine-only long-endurance search and patrol operations. In normal US Navy operations, the jet engines were run at full power (97%) to assure takeoff, then shut down upon reaching a safe altitude. The jets were also started and kept running at flight idle during low-altitude (500-foot (150 m) during the day and 1,000-foot (300 m) at night) anti-submarine and/or anti-shipping operations as a safety measure should one of the radials develop problems.
Normal crew access was via a ladder on the aft bulkhead of the nosewheel well to a hatch on the left side of the wheel well, then forward to the observer nose, or up through another hatch to the main deck. There was also a hatch in the floor of the aft fuselage, near the sonobuoy chutes.
Civilian firefighting
P-2/P2Vs have been employed in aerial firefighting roles by operators such as Minden Air Corp and Neptune Aviation Services. The fire fighters can carry 2,080 US gal (7,900 L) of retardant and have a service life of 15,000 hours. Neptune Aviation Services proposes to replace them with British Aerospace 146 aircraft, which have an estimated service life of 80,000 hours and carry upwards of 3,000 US gal (11,000 L; 2,500 imp gal) of retardant

[@davef.2329]

Just like a C-119, PRT's with pressure carburetors, no? From when was this video? Couldn't make out the date sticker on the truck's license tag at the start of the video. Thought these were all long-parked by now.

[@coronadojet]

This video was taken in July 2001