I am trying something new with this quiz. Quiz #22 is still unanswered, is tough and I anticipate it will continue unanswered over the allowed at least 500 views, but please keep trying to answer that quiz.

Meanwhile, I offer a new Quiz #23 while the prior quiz is unsolved; this feature is what is new and may keep these quizzes more of interest and alive.

Quiz #23

What was the largest single engine propellor-driven manned production aircraft ever operated by the US Navy? Largest being defined by its measured wingspan, and please no drones-they by definition are unmanned.

Name the Make, the full Model nomenclatures-of the two production versions, the official Navy "Name" of the model and its Wingspan. Bonus for naming the unique feature of its X-prototype that did not make it into production.

Hi Doug,

My guess is the Grumman Guardian. The AF2W model was the sub hunter with a crew of 4, and the AF2S was the sub killer with a crew of 3. The wingspan was 60 ft 8 in.

The XTB3F precursor had a mixed power combination, with a Pratt & Whitney Double Wasp in the front and a Westinghouse 19XB turbojet in the tail. This was found to be impractical, and the jet was removed before ever flying.

Peter.

Congratulations Peter!

You are absolutely correct on all answers.

Development of the mid-wing design Guardian started in 1944 to replace the Grumman TBF/M Avenger torpedo bomber used to destroy Japanese surface ships. First flight of the first prototype XTB3F of two was on 1 December 1945 with a P&W R-2800-48W Double Wasp radial of 2,300 Hp. In the tail was a single Westinghouse 19XB-2B turbojet to give it high-speed escape. No defensive armament was onboard, but the weapons bay could carry two torpedoes or a 4,000 lb bomb load. Two 20 mm cannon in the wings could attack shipping also. The jet boost was discontinued, but served as valuable test beds for jet engines such as the Allis-Chalmers J36 and the Westinghouse J34.

In the removal of the rear jet of the prototype, this gave spare load capability in the form of a ventral (belly) anti-submarine search radar in the XTB3F-1S, changing its mission to anti-submarine warfare.

Production models of the Guardian followed with a hunter with search radar, the AF2W and a companion AF2S killer with torpedoes, depth charges or bombs. The AF2S also carried a smaller APS-30 strike radar under wing used to pinpoint the target after detection by the companion AF2W hunter Guardian. The production aircraft had a P&W R-2800-48W Double Wasp radial rated at 2,400 hp.

The AF2 first flew on 17 November 1949, with VS-25 getting the first aircraft in October 1950. The final Guardian was the AF3S with fuselage mounted MAD gear-(Magnetic Anomaly Detection) in 1953. These submarine hunter-killer teams were active from USN aircraft carriers from 1950 to 1955. All Guardians were eventually replaced by the dual-function Grumman S-2 Tracker active from 1953 as S2F re-designated S-2 in 1962.

So the sequence of US Navy Grumman submarine hunter-killer aircraft was first the TBM-3S/TBM-3W, then the AF-2S/AF-2W and then the S-2F/S-2 in those war years.