Downloaded from https://www.everyspec.com MIL-STD-810D 19 JuIY1983 Step 1. Stabilize the test item temperature at approximately 2 A loC. Step 2. Deliver a uniform rain spray of precooled water for 1 hour (a water temperature of 5° C (41° F) at 2.5 cm/hr has proven satisfactory). : Delivery can be any convenient method per I-3.2d. , ,;. ,..[ ,Step 3. Lower the chamber air temperature to -lO° C (+14° F)‘oF”as specified and maintain the rain rate until 6 mm ofice has accumulated on all sides and on the upper surface. Wind or a side spray may be used’fo accumulate ice on the sides. .,, NOTE:
For tests representing sea spray & marine equipment, increase the ice !> depOsit to .37 mm, and use 75 Mm in .9teP~. : Step 4. Adjust the chamber air temperature to -6° C””’(+210F) for 2 to 6 hours. Attempt to operate the test item and all subsystemsat -6° C and examirie for safety hazards. ~ I Step 5. If step 4 has resulted in failure or if the specification allows ice removal, remove the ice. Limit ice removal to integral methodsplus simple, expedient, and obvious methods. Note the effectiveness of ice removal techniques. ,.:- -,. ,. ... Step 6. Attempt to operate the test item and all subsystems at -6° C and examine for safety hazards. ,. . ,, .. .Step.7.
.Repeat steps 1 through 6 with a 13 mm coating for sea spray). , - .. o .,-:,, Step 8. Return the chamber temperature.:toambient and restabilize.the test item temperature. Perform a poet-test operational checkout. of ice (75 mm Step 9. Document (with photographs if necessary) the-results for’ comparison with those obtained in II-2.2. 11-4:~’ . a. .,Previous test methods to which the test item has been subjected., : b.. Ice,thickness. ., ..: ., .,, c. Results of each performance check and visual examination: .4, ,,. ., .,.’ .,. (1) Pretest. : ~~ (2) Post test. : -d.. Ice removalmethod (if employed). . .+ ,. :,. ,,,... .. e. .Confi8urationof the’test item (i.e., shipping or operational).
,., f. Specific test conditions emplOyed. METHOD ,521.0 19 July 1983 521.0-8