This report is designed to provide information required to evaluate the Specific Aptitude Test Battery (SATB) for Airframe-and-Powerplant Mechanic from three points of view: (1) technical adequacy of the research, (2) fairness to minorities, and (3) usefulness of the battery to Employment Service staff and employers in selecting individuals for Airframe-and-Powerplant Mechanics positions. Research demonstrated a statistically significant and useful relationship between proficiency as an Airframe-and-Powerplant Mechanic and the following SATB: General Learning Ability, Verbal Aptitude, and Manual Dexterity. The validation sample consisted of 272 employed workers (including 30 blacks) from 14 states. Data were collected during 1973-1980. The tests used were the General Aptitude Test Battery. Job proficiency was measured by means of ratings by supervisors. No evidence of differences in validity for blacks and nonminorities was found. The SATB was found to be fair to both blacks and nonminorities using several definitions of fairness. The SATB can be expected to produce a useful increase in the proportion of highly competent workers. When the SATB was applied to the validation sample, an increase from 66 percent to 74 percent in the percentage of highly competent workers was found. Appended are: (1) a table of descriptive statistics for the black and nonminority subgroups of the validation sample, (2) the descriptive rating scale for supervisors, and (3) a sample Airframe-and-Powerplant Mechanic job description. (PN)