MIL-DTL-43511D
4.4.10 Ballistic resistance test. Ballistic resistance testing shall be in accordance with either
method 1 or method 2 cited in paragraph 4.4.10.1 or 4.4.10.2. Method shall be as determined by
the military service and specified in the applicable contract or purchase order.
4.4.10.1 Ballistic resistance test method 1 (for Army visors). The ballistic test at the V0 point
shall be conducted in accordance with MIL-STD-662 using a 0.22 caliber, 17 + 0.5 grain, T37
shaped projectile with the following exceptions: electronic velocity detection devices (light
beam or acoustic type) may be used to determine the velocity of the projectile, such devices
placed no less than 8 inches and no more than 24 inches from the target; compressed gas
propulsion of the projectile may be used. The sample shall be mounted on an Alderson 50th
percentile male headform in the as worn position. The 0.002 inch thick aluminum foil witness
sheet shall be mounted within 2 inches behind the area of impact. Three valid impacts shall be
made on the lens; one in the center and one in each vision area. The sample shall be considered
a failure if the aluminum foil witness sheet is punctured or if the sample is cracked. An impact
shall be considered valid only if it meets any of the following:
a. The impact velocity of the projectile is between 550 feet per second and 560 feet per second.
b. The impact velocity of the projectile is less than 550 feet per second and the impact fails to
meet the requirements in 3.5.10.
c. The impact velocity of the projectile is more than 560 feet per second and the impact meets
the requirements in 3.5.10.
4.4.10.2 Ballistic resistance test method 2 (for Air Force and Navy visors). The impact test shall
be conducted in accordance with MIL-STD-662 and using a caliber .22 T37 fragment simulating
projectile. The visor shall be rigidly mounted with the area to be impacted normal to the line of
fire. An aluminum foil witness sheet, 2 mils thick, shall be mounted 2 inches behind the area of
impact. Three valid impacts shall be made on the visor; one in the center and one in each vision
area. An impact shall be considered valid only if it meets any of the following:
a. The impact velocity of the projectile is between 550 feet per second and 560 feet per second.
b. The impact velocity of the projectile is less than 550 feet per second and the impact fails to
meet the requirements in 3.5.10.
c. The impact velocity of the projectile is more than 560 feet per second and the impact meets
the requirements in 3.5.10.
The visor containing the three valid impacts and the witness sheet shall be examined for
conformance to the requirements in 3.5.10. Any penetration on the witness sheet shall be
considered evidence of spall.
4.4.11 Abrasion resistance coating test. Before and after the abrasion tests, haze and luminous
transmittance of the coated specimens and visors shall be calculated as specified in ASTM D
1003. The abrasion test, as specified in ASTM D 1044, using an abrasion of 500 cycles with a
500 gram load, shall be performed on flat panels which are coated by the same process as the
visors. Additionally, visors shall be tested using the eraser test. The eraser test shall be
performed by rubbing with a specially standardized eraser mounted as illustrated on figure 5 and
held approximately normal to the visor. The device and eraser material indicated on figure 5
shall be used for this test. The areas of the visor where the eraser test is to be performed shall be
identified and shall include at least three areas in the critical area of vision. The eraser shall be
rubbed across the surface of the coated visor from one point to another, over the same path, for
20 complete cycles (motion of the eraser up and back is one cycle) with a force of 2.0 to 2.5
pounds continuously applied. Wherever possible, rubs of about 1 inch length are preferred.
After the rubbing has been completed, the lens shall be thoroughly cleaned to remove dirt, film,
finger marks and grease marks using a mild detergent and water followed by drying with a soft
cloth or lens tissue. The visor shall meet the requirements in 3.5.11.
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