(4) Vertical test : A minimum of three specimens must be tested and results ave-raged. For fabrics, the direction of weave corresponding to the most critical .ammability conditions mustbeparallel to thelongestdimension.Each speci-men mustbe supported vertically.The specimen mustbe exposed to aBunsen orTirrillburnerwith anominal3/8-inchI.D.tubeadjusted togivea .ameof
1
inches in height. The minimum .ame temperature measured by a calibra-
'
1
2
1
2
ted thermocouple pyrometer in the center of the .ame must be 1550F. The lower edge of the specimen must be主-inch above the top edge of the burner. The .ame must be applied to the center line of the lower edge of the speci-men.For materials coveredbyparagraph(a)(1)(i) ofPartI of thisAppendix, the .ame must be applied for 60 seconds and then removed. For materials coveredbyparagraph(a)(1)(ii) ofPartI of thisAppendix,the .amemustbe applied for 12 seconds and then removed. Flame time, burn length, and .a-ming time of drippings, if any, may be recorded. The burn length determined in accordance with subparagraph(7) ofthisparagraph mustbe measuredto the nearest tenth of an inch.
(5) Horizontal test. A minimum of three specimens must be tested and the results averaged.Each specimen mustbe supportedhorizontally.The exposed surface, when installed in the aircraft, must be face down for the test. The specimen must be exposed to a Bunsen or Tirrill burner with a nominal 3/8 inch I.D. tube adjusted to give a .ame of 1
inches in height. The minimum .ame
temperature measured by a calibrated thermocouple pyrometer in the center of the .ame must be 1550'F. The specimen must be positioned so that the edge being tested is centered主-inch above the top of the burner. The .ame
must be applied for 15 seconds and then removed. A minimum of 10 inches
of specimen mustbe usedfortimingpurposes, approximately1
12
inches must
burn before the burning front reaches the timing zone, and the average burn rate must be recorded.
(6) Forty-.ve degree test. A minimum of three specimens must be tested and the results averaged. The specimens must be supported at an angle of 45'to a horizontal surface. The exposed surface when installed in the aircraft must be face down for the test. The specimens must be exposed to a Bunsen or
Tirrillburnerwith anominal3/8inchI.D tubeadjusted togivea .ameof1
12
inches in height. The minimum .ame temperature measured by a calibrated thermocouple pyrometer in the center of the .ame must be 1550'F. Suitable precautions must be taken to avoid drafts. The .ame must be applied for 30 seconds with one-third contacting the material at the center of the specimen and then removed. Flame time, glow time, and whether the .ame penetrates (passes through)the specimen must be recorded.
(7)
Sixty degree test. A minimum of three specimens of each wire speci.cation (make and size) must be tested. The specimen of wire or cable (including insulation) mustbeplaced at an angle of60'with thehorizontalin the cabinet speci.edin subparagraph(3) ofthisparagraph withthe cabinetdoor open during the test, or must be placed within a chamber approximately 2 feet highby 1footby 1foot, open atthetop and at one vertical side(front), and which allows su.cient .ow of air for complete combustion, but which is free from drafts. The specimen must be parallel to and approximately 6 inches from the front of the chamber. The lower end of the specimen must be held rigidly clamped.The upper end of the specimen mustpass over apulley or rod and must have an appropriate weight attached to it so that the specimen is held tautly throughoutthe .ammability test.Thetest specimenspanbetween lowerclamp and upperpulley orrod mustbe24inchesand mustbe marked8 inches from the lower end to indicate the central point for .ame application. A .ame from a Bunsen or Tirrill burner must be applied for 30 seconds at the test mark. The burner must be mounted underneath the test mark on the specimen, perpendicular to the specimen and at an angle of 30'to the vertical plane of the specimen. The burner must have a nominal bore of 3/8-inch, and must be adjusted to provide a 3-inch high .ame with an inner cone approximately one-third of the .ame height. The minimum temperature of the hottest portion of the .ame, as measured with a calibrated thermocouple pyrometer, may not be less than 1750'F. The burner must be positioned so that the hottest portion of the .ame is applied to the test mark on the wire. Flame time, burn length, and .aming time of drippings, if any, must be recorded. Theburnlengthdeterminedin accordance withparagraph(8) of thisparagraph mustbe measured tothe nearesttenth of aninch.Breaking of the wire specimens is not considered a failure.
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 4(49)
