This test method covers determination of the effects of cleaning solutions and chemical maintenance materials on painted aircraft surfaces. Materials used for testing shall be drawing pencils, fine sand paper, abrasive mats, acetone, MIL-PRF-85285 coating, MIL-PRF-23377 primer coating, chemical conversion materials, and distilled or deionized water. Plate and sheet specimens of aluminum alloy shall be examined under concentrated and diluted test solutions. Pencils preparation, panels preparations, testing, and hardness determination shall be done according to the indicated procedure.

1.1 This test method covers determination of the effects of cleaning solutions and liquid cleaner concentrates on painted aircraft surfaces (Note 1). Streaking, discoloration, and blistering may be determined visually. Softening is determined with a series of specially prepared pencils wherein determination of the softest pencil to rupture the paint film is made.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.