In the 1960s, Aero Union acquired five former US Navy AF-2 Guardians. Only two were fully converted to airtanker (N9995Z and N3144G), a third was partially converted, and two remained unused and unconverted. The latter three remained in storage at Chico, CA for many years.
Falsely painted as N9995Z, the Guardian at the Pima museum is in fact N9994Z, which was one of the unconverted aircraft. Aero Union donated it to the Pima Air Museum in 1991, restoring it to static display condition the previous year. Although this aircraft had never been an airtanker and had never seen service with Aero Union, they painted it in their full markings to resemble Aero Union's airtanker N9995Z / 21-E.

This photo is copyright © Aad van der Voet, and may not be used or published in any way without permission.

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