1、BRITISH STANDARD AEROSPACE SERIESBS3G.100-2.3.2:1970Incorporating amendment issued June 1972 (AMD 984)Specification forGeneral requirements for equipment in aircraft Part 2: All equipment Section 3: Environmental conditions Subsection 3.2: Temperature pressure requirementsUDC 629.7.051.06:620.193.21
2、BS 3G.100-2.3.2:1970This British Standard, having been approved by the Aerospace Industry Standards Committee, was published under the authority of the Executive Board of the Institution on 28 October 1970 BSI 07-1999The following BSI references relate to the work on this standard:Committee referenc
3、e ACE/58Draft for comment 68/16439ISBN 580 06084 5Amendments issued since publicationAmd. No. Date of issue Comments984 June 1972 Indicated by a sideline in the margin4137 December 1982BS 3G.100-2.3.2:1970 BSI 07-1999 iContentsPageForeword ii1 Scope 12 Field of application 13 Definitions 14 Classifi
4、cation and grading 14.1 Aircraft classification 14.2 Equipment grading 24.2.1 Civil grades 24.2.2 Military grades 24.2.3 Grade suffix 25 General test requirements 36 Tests 36.1 Low temperature tests 36.1.1 Test A: Ground survival 36.1.2 Test B: Ground operation 36.1.3 Test C: Flight operation 46.2 T
5、emperature/humidity sequence 46.2.1 Test D 46.3 High temperature ground conditions 66.3.1 Test E: Ground survival 66.3.2 Test F1: Ground operation (short term) 66.3.3 Test F2: Ground operation (long term) 66.4 High temperature flight 76.4.1 Test G: Low altitude 76.4.2 Test H: Intermediate altitude 7
6、6.4.3 Test J: High altitude 7 Appendix A Basis of climatic temperature levels 11Appendix B Measurement of ambient temperature 11Appendix C Temperature conditions related to risk 11Table 1 Temperature and pressure parameters for equipment on civil and military aircraft 8Table 2 Additional temperature
7、 and pressure parameters for equipment on military aircraft 9Table 3 Atmospheric temperatures, maxima and minima for northern latitudes 12BS 3G.100-2.3.2:1970ii BSI 07-1999ForewordThis British Standard is part of a composite standard in the Aerospace series of British Standards specifying general re
8、quirements for equipment in aircraft. An introduction to the complete British Standard is given in BS 3G.100-01).This subsection of BS 3G.100 replaces in part the environmental requirements specified in Clauses 202 to 209 of BS 2G.100-2:1962. It details climatic environments against which aircraft e
9、quipment should be designed, and also defines climatic tests from which the necessary selection should be made to demonstrate that the equipment will be satisfactory for its operational environments. These functional characteristics do not necessarily determine the life or reliability of the equipme
10、nt which should be dealt with by the individual relevant specification. Although in practice an almost infinite variety of environmental conditions may be encountered, depending on the class of aircraft and grade of equipment, etc., it is considered highly desirable to group together standardized te
11、st conditions which, when applied in a standard sequence, will demonstrate the operational capability of an item of equipment and yet, as an aid to equipment manufacturers, keep to a minimum the number of grades. The standard contains a schedule listing the tests and operational environments applica
12、ble to various equipment grades.This Standard makes reference to the following British Standards:BS 3G.100-2.3.0, Standard test requirements.BS 3G.100-2.3.7, Tropical exposure.BS 3G.100-2.3.X1), Icing requirements.NOTE Information concerning SI units is given in BS 350, “Conversion factors and table
13、s”, and PD 5686, “The use of SI units”.A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application.Compliance with a British Standard does not of itself confer immunity from legal obligations.Summ
14、ary of pagesThis document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 12 and a back cover.This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.1) In course
15、of preparation.BS 3G.100-2.3.2:1970 BSI 07-1999 11 ScopeThis subsection of BS 3G.100-2 specifies climatic design and test requirements in addition to providing guidance in the test procedures for those responsible for the formulation of the climatic requirements clauses that will appear in detailed
16、equipment design or requirement specifications. It is intended that this document will permit the selection of specific test conditions and methods that will unambiguously define the climatic acceptance requirements for specific equipment in aircraft.2 Field of applicationAlthough this British Stand
17、ard is intended to apply to equipment for general aircraft use, it may also be useful for application to equipment designed for use in specific aircraft. In such cases the relevant individual specifications should state what additional tests or amendments to these standard tests are necessary to mee
18、t precise requirements, e.g., in the case of transonic or high performance aircraft having a short-term high-speed capability, the conditions and duration of Test G, H, or J may not be adequate and may need to be supplemented.Not all the tests listed are necessarily applicable to a particular equipm
19、ent (e.g., the low-altitude high-speed flight condition, Test G). Furthermore, although the tests are shown in the sequence considered to be the most practical and logical, it may not be ideal for a particular test programme. In these circumstances the individual specification should select from thi
20、s standard the appropriate tests and state the sequence in which the tests are to be applied.Information on the basis of the climatic temperature levels is given in Appendix A.3 DefinitionsFor the purposes of this subsection of this British Standard the following definitions apply:3.1 idleisolated f
21、rom the source or sources of power3.2 operateto cause an equipment to carry out some or all of the services and functions (as stated in the relevant specification) for which it is intended3.3 performancethe demonstration in quantitative terms of the function(s) of an equipment to defined requirement
22、s4 Classification and gradingFor the purposes of this subsection of this British Standard, the environmental tests applicable to equipment shall be graded as below; a complete description of the environmental tests require the main grade identification letter with suffix numeral (e.g. C.3). Table 1
23、and Table 2 state the environmental test parameters for each grade.4.1 Aircraft classification. The classes of aircraft specified in this subsection are as follows:Class I Rotorcraft and low-performance aircraft. This class includes all low-performance aircraft such as helicopters, “club” aircraft,
24、piston-engined executive aircraft and, in general, all unpressurized aircraft with a nominal ceiling of 6 100 m (20 000 ft). It is probable that these aircraft will use outside air for cooling and have a simple heating system using waste engine heat.Class II. Subsonic aircraft. This class includes m
25、ost passenger civil aircraft, flying up to speeds of Mach 095, and having ceilings of 15 220 m (50 000 ft). Certain compartments will be pressurized and/or provided with heating and cooling systems.Test G is a special test that has been included for military aircraft that have low-level speeds up to
26、 about Mach 0.95, although remaining subsonic at altitude. The reason for this special test is that the high temperatures experienced at low level will not be encountered by high-altitude civil aircraft.Class III. Transonic aircraft. This class is primarily for military aircraft with maximum speeds
27、up to Mach 1.3 and altitudes up to 18 300 m (60 000 ft) but with low-altitude speeds not greater than 1 300 km/h (700 knots) (i.e. Mach 106 at sea-level).Test H has been introduced to this class of aircraft because the combination of flight temperature and air density can be a hazard not covered by
28、the conditions of Tests G and J.Class IV. Supersonic or high-performance aircraft. This class includes all high-performance aircraft, but for the purpose of this standard is restricted to aircraft having, in the main, light alloy airframes, the temperature limit of which is considered to provide a c
29、onvenient boundary. This limit is taken as a temperature of 150 C and represents Mach numbers up to about 2.2 in cool ambient conditions. Short bursts of high speed may occur, but only equipment of low thermal capacity will be affected.BS 3G.100-2.3.2:19702 BSI 07-1999Maximum low-altitude speed will
30、 be about 1 500 km/h (800 knots) (i.e. Mach 1.2 at sea level) but for economic cruising Mach numbers of 09 and 095 would be more common. The maximum altitude is likely to be 21 300 m (70 000 ft) with minimum cruising speeds of Mach 07 to 0.9.NOTE For aircraft having a performance outside the maximum
31、 speeds indicated for Class IV, there is insufficient evidence at present to give detailed temperature environments. Such aircraft would have airframes of heat-resisting material. However, it is not likely that temperature-and pressure-controlled zones will differ from Class IV. For unconditioned ba
32、ys the temperature will depend upon the degree of insulation and flight time. For externally mounted equipment and for equipment in uninsulated bays temperatures will be of the following order:This information is offered for guidance; the aircraft manufacturer should be consulted for more details.4.
33、2 Equipment grading4.2.1 Civil and military grades4.2.2 Additional military grades4.2.3 Grade suffixMach No. Temperature2.5 185 C3.0 290 C3.5 415 CGrade A Equipment mounted in the temperature controlled and pressurized region of Class II or IV aircraft, with pressure not lower than that correspondin
34、g to an altitude of 3 000 m (10 000 ft).Grade B Equipment in the temperature controlled but unpressurized region of a Class I aircraft.Grade C Equipment in the temperature controlled but unpressurized region of a Class II aircraft.Grade D Equipment in the temperature controlled but unpressurized reg
35、ion of a Class IV aircraft.Grade E Equipment in non-temperature controlled and unpressurized regions and in externally exposed locations of Class I aircraft.Grade F Equipment in non-temperature controlled and unpressurized regions and in externally exposed locations of Class II aircraft.Grade G Equi
36、pment in non-temperature controlled and unpressurized regions and in externally exposed locations of Class IV aircraft.Grade H Equipment located in the engine bay of a Class I aircraft.Grade J Equipment located in the engine bay of a Class II aircraft.Grade K Equipment located in the engine bay of a
37、 Class IV aircraft.Grade Q Equipment mounted in the temperature controlled and pressurized region of Classes II, III and IV aircraft, with pressure not lower than that corresponding to an altitude of 9 100 m (30 000 ft).Grade R Equipment in the temperature controlled but unpressurized region of a Cl
38、ass III aircraft.Grade S Equipment in the temperature controlled but unpressurized region of a Class IV aircraft, but having prolonged capability of high performance flying at low or intermediate altitudes.Grade T Equipment in non-temperature controlled and unpressurized regions and in externally ex
39、posed locations of Class II aircraft, but having capability for prolonged high-speed flight at low altitudes.Grade U Equipment in non-temperature controlled and unpressurized regions and in externally exposed locations of Class III aircraft, bur having capability for prolonged high-speed flight at l
40、ow and intermediate altitudes.Grade V Equipment in non-temperature controlled and unpressurized regions and in externally exposed locations of Class IV aircraft, but having capability for prolonged high-speed flight at low and intermediate altitudes.Grade W Equipment located in the engine bay of a C
41、lass III aircraft.Grade .1 Equipment installed in aircraft intended for world wide use and with the equipment located in the aircraft such that when deployed in tropical regions the equipment would be significantly influenced by solar radiation*.BS 3G.100-2.3.2:1970 BSI 07-1999 35 General test requi
42、rementsFor the purposes of this British Standard the standard test requirements specified in British Standard BS 3G.100-2.3.0 shall apply, where appropriate.6 TestsThe appropriate climatic conditions for an equipment shall be selected from Table 1 and Table 2. The tests shall be applied in the order
43、 given, unless otherwise stated in the relevant individual specification.6.1 Low temperature tests. The temperature conditions for Tests A and B given in Table 1 and Table 2 are ground conditions applicable to all aircraft types, but in Test C the levels given for the uncontrolled temperature zones
44、allow for the minimum temperature rise due to kinetic heating. In Test C the temperature requirement for Grades A, B, C, D, Q, R and S is an arbitrary level selected as the lowest long-term temperature likely to occur in a semistagnant area within temperature controlled regions (e.g., the space behi
45、nd an electronic equipment).6.1.1 Test A: Ground survival. This test is applicable to all equipment irrespective of aircraft type and simulates the lowest ground temperature experienced by aircraft in cold climates. The temperature specified should be considered applicable to all equipment irrespect
46、ive of region, since an aircraft may be idle on the ground long enough to allow thermal stabilization.Equipments is not normally expected to be capable of operation at these temperatures, but to survive them without damage.The lowest temperature of 62 C applies to aircraft operating into and from ar
47、ctic areas, the 40 C conditioning represents deployment into areas no more severe than sub-arctic.6.1.1.1 Test A details. The equipment in its idle state (see 3.1) shall be subjected to the appropriate low-temperature conditioning for Test A selected from Table 1 and Table 2, until temperature stabi
48、lization is achieved (see BS 3G.100-2.3.0) and maintained under these conditions for a further 2 hours.Unless otherwise specified, the equipment shall not be operated during the test, but should if possible be visually examined towards the end of the temperature conditioning to determine whether det
49、erioration likely to impair future performance has occurred.If required by the relevant specification, the equipment shall be examined visually or performance tested after regaining room temperature. Otherwise, the equipment should be immediately submitted to Test B as specified in 6.1.2.6.1.2 Test B: Ground operation. This test simulates the low-temperature conditions under which an equipment may be required to be switched-on or started up and/or operated. For equipment grades A, B, C, D, Q, R and S (stated in Table 1 and Table 2) this condition would persist
