April Mystery Airplane Contest

In August 1989, I attended the Abbotsford Airshow in British Columbia. It was my introduction to the use of the Grumman Tracker as a firebomber. Three Conair Trackers, each with a different color water, made a formation pass over the runway, followed by a DC-6. Conair later modified its Trackers with PT-6 turboprops to create the Firecat with 870 gallons of retardant.

The state of California began its use of Cyclone engine Trackers in 1973, each with an 800 gallon capacity. These were designed to replace the much older Avengers and Tigercats. In 1987, Marsh Aviation converted a piston Tracker to turboprops for greater load carrying ability.

CAL FIRE followed this in 1996 by acquiring 26 surplus US Navy S-2E and S-2G Trackers for conversion to tankers. These were stripped of all military equipment and outdated internal components and given a total rebuild. Powered by 1,650 hp Garrett turboprops, the "new"

aircraft, registered as Marsh Turbo Trackers, can carry 800 to 1,200 gallons of water when used for firefighting.

Marsh also converted piston Trackers to Garretts for military use by Argentina and Taiwan as well as air tankers for Turkey and France. CAL FIRE quotes a top speed of 270 mph for operations at 29,150 pounds gross weight. The last Turbo Tracker was delivered to CAL FIRE in 2005. They

currently operate 23 S-2Ts.

N442DF began life as a Grumman S-2E and served with VS-35 and VS-33 for anti-submarine operations. Updated to an S-2G, it was struck off charge on 15 September 1975 and sent to Davis-Monthan, Arizona, for storage. Now Tanker 94, it is used for rapid response to wildfires carrying 1200 gallons of fire retardant. I photographed Tanker 94 and its companion, Tanker 89 (N425DF), at the Reno Air Races in September 2016. They, and an ancient Neptune, were operating against fires near Susanville, California. Early in the week, they would head out and return, their bellies red with retardant.

A half-dozen readers nailed this one as a Marsh Turbo Tracker. I gotta stop leaving the N-number visible! This month's winner Tom Kelly wrote, "These have been rebuilt for years for the California Department of Forestry at my home field by Marsh Aviation, Falcon Field, Mesa,

Arizona." Thanks, Tom. Best wishes. Blue skies and tail winds for summer.