 |
|||
|
|
|||
| ||||||||||
|
|  MIL-T-50760(MU)
through the excursion specified in 3.6.1 without slippage or rotation under
its own weight, and for establishing coincidence of the 3 indices of the
telescope with respect to the calibrated vertical index and geometric axis
of the telescope's tube as specified in 3.6.4.
c. Targer Projector collimator. - The target projector collimator
shall have a clear aperture of at least 2 inches. The target reticle of
the projector collimator shall contain a 0.50 mil diameter circle at the
intersecting point of the horizontal and vertical reticle lines to deter-
mine conformance with collimation, as specified in 3.6.1. Tolerance marks
shall also be incorporated on both sides of the vertical reticle line to
determine conformance to parallelism of reticle and image, as specified in
3.6.4 Unless otherwise specified, the target projector collimator shall
be set at infinity focus. The zero line of sight of the target collimator
shall be set with the line of sight in the same horizontal (level) plane
of the geometric optical axis (the nominal line of sight of the telescope)
within 10 seconds. The vertical reticle line of the collimator shall be
adjusted plumb.
d. Collimating telescope. - A calibrated collimating telescope of
at least 3 power (3X) containing a horizontal and vertical reticle line
shall be utilized for alignment of the "V" block with respect to the geo-
metric optical axis of the target collimator. Position the telescope in
the "V" block with the vertical reticle line of the telescope adjusted
plumb when in the test position. While observing through the telescope,
establish coincidence of the intersecting point (horizontal and vertical
reticle lines) of the telescope with respect to the intersecting point
(horizontal and vertical reticle lines) of the target image. The tele-
scope shall then be rotated 3200 mils (90 to the left and 90 to the right)
from the established position ahove to determine repeatability of the test-
ing equipment prior to performing any accuracy tests of the telescope assembly.
4.5.2.3.2 Sealing. - Special testing equipment to test sealing of the
telescope shall conform to the internal pressure test requirements of Draw-
ing F8454445, Pressure Tester - Two Station.
4.6 Test methods and procedures.
4.6.1 Storage temperature (-80F). - The testing equipment utilized in
this test shall be in accordance with the "Test Facilities" requirements of
MIL-F-13926 and the conditions of 3.5.l. The telescope shall be placed in
the test chamber and the temperature of the chamber reduced gradually (see
NOTE) tpo -80F. The telescope shall remain at this temperature for a mini-
mum of 2 hours. At the completion of this 2 hour period, the temperature
of the test chamber shall be gradually raised to room temperature (+60 to
+90F). At the end of a 1 hour period the telescope shall be removed from
the test chamber and subjected to test in 4.6.1.1. Upon completion of the
test in 4.6.1.1 the telescope shall be subjected to a visual and tactile ex-
amination for evidence of physical failure. The telescope shall meet the
requirements of 3.5.1. The telescope shall then be subjected to the test
in 4.6.1.2.
NOTE: The rate of temperature change in the test chamber shall not
exceed 20 degrees per hour throughout the temperature cycling
tests in 4.6.1 and 4.6.1.2.
8
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals