1、O ARMY REGULATION NO. 70-38 3515789 0170001 893 H This copy is a reprint which includes current pages from Changes 1. DEPARTMENT OF THE ARMY WASHINGTON, DC 1 August 1979 RESEARCH, DEVELOPMENT, AND ACQUISITION r- 2 7 -O 7 RESEARCH, DEVELOPMENT, TEST AND EVALUATION OF - MATERIEL FOR EXTREME CLIMATIC C
2、ONDITIONS Effective 1 September 1979 This is a complete revision of AR 70-38. It reflects chunges in policy, guidance, and climatic criteria, and conforms to MIL-STD-Z1OB, Climatic Extremes for Military Equipment, 15 De- cember 1373. Local supplementation of this regulation is prohibited, except upo
3、n approval of the Chief of Engineers. Interim changes to this regulation are not official unless they are authenticated bp The Adjutant General. Users will destro# interim changes on their expiration dates unless sooner superseded or rescinded. CHAPTER 1. 2. SECTION I. II. III. APPENDIX A. GENERAL P
4、OLICIES AND PROCEDURES Purpose . . . . . . . . , . , . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 Applicability . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . .
5、 . . . . . . . 1-2 Explanation of terms . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . 1-3 Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6、. . 1-4 Design and test policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . , . . . . . . . . . 1-5 Major responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6 Limitations . .
7、. . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7 Application of design values . . , . . . . . , . , . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . 1-8 Climatic testing . . . . . . . . .
8、, . . . . . . . . . . . . . . . . . . , . , , . . . . . . . . . . . , . . . . . . . , . . . . , . . . . . 1-9 CLIMATIC CRITERIA GENERAL Climatic design types . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 Summary of daily cycles . .
9、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2 High elevation and upper air conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 CLIMATIC DESIGN TYPES Hot climatic design type. . . . . . . . . . . .
10、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4 Basic climatic design type . . . . . , . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , , . . . . . . 2-5 Cold climatic design type . . . . . . . . . . , . . . . . . . . . . . . . . .
11、. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 Severe cold climatic design type . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . .,. . . . . . . 2-7 Additional environmental elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12、 . . 2-8 Combined environmental effects . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . 2-9 DISTRIBUTION OF CLIMATIC DESIGN TYPES Map of climatic design types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13、 . 2-10 Delimitation of climatic design types . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . 2-11 Puwrph RELATIONSHIP BETWEEN AR 70-38 AND MIL-STD-21OB T8bles 2-1. Summary of Temperature; Solar Radiation, and Relative Humidity Daily Cycles 2-2. Hot Climatic Desig
14、n Type; Hot-Dry Daily Cycle of Temperature, Solar Radia- tion, and Humidity (QSTAG 360 Category Al). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3. Hot Climatic Design Type: Hot-Humid Daily Cycle of Temperature, Solar Radia- tion, and Humidity. (QSTAG 360 Category B3) . . . . . . .
15、 . . . . . . . . . . . . . . . . . . . . . . . %irr regulation supersedes AR 70-38, 5 May 1969. pue 1-1 1-1 1-2 1-3 1-3 1-4 1-5 1-5 1-5 2-1 2-1 2-2 2-3 2-7 2-14 2-14 2-16 2-20 2-20 2-20 A-1 P4e 2-2 2-4 2-6 1 Licensed by Information Handling ServicesProvided by IHSNot for ResaleNo reproduction or net
16、working permitted without license from IHS-,-,-W 3515789 0170002 72T W +e“ AR ,70-38 L 1 August 1979 .o. Tables 2-4. Basic Climatic Design Type: Constant High Humidity Daily Cycle of Temper- ature, Solar Radiation, and Humidity. (QSTAG 360 Category B1) 2-5. Basic Climatic Design Type; Variable High
17、Humidity Daily Cycle of Temper- ature, Solar Radiation and Humidity (QSTAG 360 Category B2) . 2-6. Basic Climatic Design Type; Hot Daily Cycle of Temperature, Humidity, and 2-7. Basic Climatic Desgn Type; Cold Daily Cycle of Temperature, Humidity, and Solar Radiation (QSTAG 360 Category Cl) -2-8. Co
18、ld Climatic Design Type; Daily Cycle of Temperature, Humidity, and Solar Radiation (QSTAG 360 Category C2) Solar Radiation. (WSTAG 360 Category A2). Figures 2-1. Areas of Occurrence of Climatic Design Types 2-2. Distribution of Absolute Maximum Temperatures 2-3. Distribution of Absolute Minimum Temp
19、eratures ii -. Pwe 2-8 2-9 2-1 1 2-13 2-16 . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3535789 0170003 666 . 1 Auguat 1979 AH- 70-38 O “ CHAPTER 1 GENERAL POLICIES AND PROCEDURES 1-1. Purpose. This regulation prescribes policies, responsibiliti
20、es, and planning guidance for realistic consideration of climatic conditions in the research, development, test, and evalua- tion (RDTE) of material used in combat by the Army. The principal classes of materiel used in combat are- a. Mechanical assemblies for ground use (e.g., tank). b. Mechanical a
21、ssemblies for air use (e.g., c. Electrical and electronic equipment (e.g., d. Optical equipment (e.g., rangefinder). e. Weapons (e.g., missile). f. Ammunition (e.g., artillery shell). helicopter). radio). 0- g. Hydrocarbon fuels and lubricants. h. Construction materials and equipment. 1-2. Applicabi
22、lity. a. This regulation applies to items of materiel- (1) Developed by the Army. (2) Developed by another Service to meet (a) Approves the requirements docu- (b) Has budget responsibility. (c) Is the user. Armys requirements and Army- ments. B. For materiel developed for the sole use of another ser
23、vice, the policy of the using service will apply. c. This regulation does not apply to the Army National Guard or the Army Reserve. d. It defines the climatic conditions materiel may be exposed to and gives guidance in the selection of appropriate test levels for some test procedures. It does not de
24、fine test procedures, because there may be valid reasons for per- forming tests under conditions that are not en- tirely realistic. Four climatic design types, df- ferentiated by temperature characteristics, are in chapter 2. These design types give guidance in preparing requirements documents and o
25、ther documents covering RDTE . and procurement of Army materiel. A map showing locations of the four types of design criteria is included (fig. 2-1). c. This regulation is concerned primarily with the mechanical operation or functioning of mate- riel under the extremes of climate to which it is like
26、ly to be exposed. It is recognized that some environmental elements or conditions (smoke, haze, fog, shimmer, and clouds, for example) may affect the ability of some materiel, particu- larly electro-optical equipment, to perform its mission. Unfortunately, the effects of these en- vironmental factor
27、s on the operation of electro- optical devices cannot be reliably quantified at this time. Therefore, design criteria for visibility requirements are not given in this regulation. f. Although climate is the most important ele- ment of the total natural environment as far as military equipment design
28、 is concerned, other environmental elements such as vegetation, soils, landforms, and biological agents also affect the performance of materiel. In some cases, these factors may be more responsible for de- terioration and failure than climate. No attempt is made to specify criteria for these nonclim
29、atic elements in this regulation. It is recommended that, wherever appropriate, they be stated in requirement documents. g. Provisions of this publication are the sub- ject of international standardization agreements (QSTAG 360 and STANAG 2831). When amend- ment, revision, or cancellation of this pu
30、blication is proposed that will affect or violate the inter- national agreements concerned, the proponent will take appropriate reconciliation action 1-1 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3515789 AR 70-38 through international standardi
31、zation channels. 1-3. Explanation of terms. The following terms apply to this regulation. a. Climatic design types. Four climatic design types are differentiated on the basis of worldwide temperature regimes. They are- (1) Hot climatic design type. (2) Basic climatic design type. (3) Cold climatic d
32、esign type. (4) Severe cold climatic design type. Areas of the world where these types apply are shown in figure 2-1. The climatic values included in the design types represent the extreme condi- tions materiel is likely to encounter in the field, with allowance for some risk (see 1-5b and app A). 6
33、. Daily weather cgcles. Each of the climatic design types is characterized by one or more daily weather cycles, which show the interac- tions and daily patterns of temperature, humid- ity, and solar radiation (where applicable). (1) Four cycles represent the basic design type. (a) One for the hottes
34、t days and one for the coldest days likey to be found in the basic design areas. (b) Two cycle represent areas where high humidities are a major problem. Materiel that can operate satisfactorily under all four of these daily weather cycles should be cap- able of satisfactory performance throughout t
35、he areas of the basic design type. (2) The hot climatic desigri type is charac- terized by two daily weather cycles, one repre- senting the highest temperatures likely to be found anywhere in the world, and the other rep- resenting extremely high dewpoints. (3) The cold climatic design type and the
36、se- vere cold climatic design type are each repre- sented by one daily weather cycle, the latter representing the lowest temperatures in which matericl operation is rc!quired. Details of the daily weather cyrles that make up 1-2 - 7 1040 0170004 5T2 1 August 1979 the climatic design types are given
37、in section II, chapter 2. c. OpeyatiotzaZ, and storage and tramit con- diti0n.s. In each of the eight daily weather cy- cles, a distinction is made between operational temperature and humidity conditions, and stor- age and transit temperature and humidity condi- tions. (1) Operatiorml conditions. Th
38、ese are clima- tic conditions in the open to which materiel might be subjected during operations or standby for operations. Ambient temperature and humidity conditions are those measured under standard conditions of ventilation and radiation shielding in a meteorological shelter at a height of 4 to
39、6 feet (1.2 to 1.8 meters) above the ground and determined according to the risk policy in paragraph 1-5b. Solar radiation which. might be experienced concurrently with the temperature and humidity is also stated for many of the climatic conditions. Although the standard conditions measured in meteo
40、rological shelters are usually not exactly the same as the operational environment for materiel, it is necessary to state operational Conditions in standard terms so- (a) Measurements have the same meaning in all parts of the world. (b) The great range of variations in re- sponse of different materi
41、el to a given climatic condition is not a complicating factor in setting design criteria. For example, the temperature of the materiel it- self may vary considerably from the operational air temperature because of the effects of incom- ing solar radiation, internal sources of heat, the thermal mass,
42、 and the heat transfer characteris- tics of the materials. Most items exposed to the sun will attain higher temperatures than the air temperature. The exact temperature can be ob- tained through actual or simulated exposure to the appropriate daily cycle, or through the de- velopment and use of suit
43、able mathematical models. (2) St.orrr!/f tl.?Itl /rtr.r/sil c*or/cli/io,/s. Ih(!HC WC) tcwq)cwturcb ;ud hrrrnidity (.ontlitions tnatv- rid might bv subjwted to in storag,rch :mti trtrnsit Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3535789 OL7000
44、5 439 1 August 1979 situations. Examples of these situations are- shelter. Y (U) Inside an unventilated field storage (h) In a railway boxcar. Because of great differences in temperature and humidity in varying storage modes, the severity of the exposure depends upon the choice of stor- age mode as
45、much as the storage location. This is very important in areas of extreme soiar radia- tion and high humidities. Storage and transit air temperature and humidity may differ from oper- ational temperature and humidity because of the induced effects of heat gains or losses of air in confined spaces. Wh
46、ere a large thermal mass is involved (e.g., in food storage), the temperature of the stores may be much iower than the stor- age air temperature stated, and may have little daily variation. Temperature for such a thermal mass is derived by using data rom previous similar storage conditions or is det
47、ermined by actual measurement under current conditions. . 1-4. Objective. It is intended that this and re- lated regulations will help the Army achieve the objective of developing materid that will per- -. form adequately under the environmental condi- tions likely to be found in the areas of intend
48、ed use. 1-5. Design and test policy. (L. Areas of poten- tial use for Army materiel include all parts of the world except the Antarctic continent. Standard general purpose materiel will be designed for safe and effective use under the specified condi- tions of the basic climatic design type (defined
49、 in chap. 2). Materiel for use under the conditions of extreme climatic design types (hot, cold, and se- vere cold) will be provided by designing- (1) Special materie1 capable of such use. (2) Special materiel solely for scch use. (3) Modification kits which adapt new standard materiel or previously type-classified standard materiel. The approach chosen will be that which gives satisfactory results most economically, consid- ering the extent of deployment in each area of * AR 70-38 potential use,
