AIA/NAS 888-2013 pdf download SIGHT LEVELS FOR OPTICAL TOOLING
SIGHT LEVELS SHALL BE FABRICATED TO, OR HAVE ADJUSTMENT CAPABILITY TO ACHIEVE THE FOLLOWINGACCURACIES:
VERTICAL AND HORIZONTAL RETICLE CROSS HAIR PATTERNS TO BE ORTHOGONAL TO WITHIN土1/2°AND THE HORIZONTAL RETICLE CROSS HAIR PATTERN SHALL BE PERPENDICULAR TO THEVERTICAL AXIS SO THAT A SCOPE SWEEP ON A SINGLE POINT IS WITHIN FIVE (5) ARC SECONDS ASVIEWED THROUGH THE SCOPE
LINE OF SIGHT (L.O.S,) TO REMAIN IN A LEVEL PLANE THROUGHOUT 36 ROTATION ABOUTVERTICAL AXIS TO WITHIN FIVE (5) ARC SECONDS.
LINE OF SIGHT (L.O.S,) TO REMAIN STRAIGHT FROM MINIMUM FOCUS TO 50 FT. RANGE WITHIN0.002 INCHES AND FROM 50 FT.TO 100 FT.WITHIN 0.004 INCHES.
OPTIONAL OPTICAL MICROMETE MEASURING RANGE AT ANY INTERVAL MEASURED FROM ZERO TOBE WITHIN 0.001 INCHES AND BACKLASH NOT TO EXCEED 0.001 INCHES