(2) Procedure II - Operation. Prooedtire II ia uaed to determine the

parformanca c; the test item at low teqperatures and can be preceded by prcoadxa I, procedure III, or both. If the test item is to be stored at lew tenperatiires before uae, procedis>e I is conducted before procedure II. If a aanipulatim test is required. procedxa<e III can precede tbe operational test. If tbe teat itea ia not intended to be stored at low temperature or manipulated before tae, in4>cedure II is conducted directly.

(3) Profurs III - aanlpulstiea. Froas&is 111 ia used to detersdne the ease with ttilch the test item can be set up and disasseafeled by personnel wearing heavy, cold-waather clothing. Storage testing, operational testing, or both oan precede the manipulation teat if required.

1-3.2 Choice of related test conditions. After choosing the test ртосеаглСв}. choose the test tenperatures, test duration, test item conf igia*ation. and any

additional impropriate citlons.

a. Teft tenaaeratxse. The specific test tenperatures are preferably aelected froa the requiremanta docunanta. If this information is not available, deteraination of test tenperature(s) should be based on the world areas in Aieh tbe test itea will be

ussd, plus any additicr,al considaraticns. Tha inforaation below provides guidance for loosing the test teBK>eratts<es for;

- Selected regions.

- ebridwide use without extended storage.2./

Vtorldwlde use with extendad storage periods.

(1) Selected regions Table 502.3-1 and tba amp in Oanaral Raquireaants. figure 4. oan be uaed to detenaine the test teaperature aiien tbe test itea is to be used at specific regions only, тае air teaperature extraaaa Shoan in table 502.3-Z are based on a one percent frequency of occurrence of the bours during tbe most severe month at the most severe location within the gecgr&];.ical Mcoapassed by the climatic region, exo pt for severe oold, 4iiab is based on a 20 percent probability of occurrence. Tbe values shoan represent the range of tbe diurnal cycle. For this method, the loaast value in each range is usually considered.

(2) Wbrldwide use. Wien the test item is to be stored or operated

throughout tha world, tpsratups salacticn aust include not only oansidsratior. of Ше abeolute cold, but also of tt irmqumneiy at a glvMi aeld condition. Qnless frequency is considered, it is possible to create an overtest condition. In teral of frequency, tbe probability-of-occurrence values shoan below refer to the percent of total hours, in the most extreme month and area in the world,

2/ uctended storage is defined ms storage for 2 years or longer.

MSrmo 502,3

TABLE 502.3-1. f ip tenperature diumal evcle f nperature глглла. 3/

Climatic Begion

Location

Temperature Operational

Induced

Mild Cold (00)

Gold (G2)

Severe Cold (СЭ):

OMStal areaa of Шва tern Europe under prevailing maritime infltMnce, southeaet Australia, lc dands of mm Zealand

Basic cold (Cl) ;

Moat of Europe Kortbem contiguou Southern <?anBda

High-latitude ooaata (e.g., southern coast of Alaska

High elevations in lomer latitudes

Alaska (excluding the interior

Greenland (excluding

the oold pole) Sorthem Sowndinavia Bsrtfasm Asia (soas

areas) High Elevations

(Morthera and Southern Bsadsidieres) Alps

Biiaklayas

Interior of Alaska

TUcon (Canada) Interior of the

Bcrtham Islands tt-eenlMid Ice Ста Horthem Asia

-6°C to -19°C (21°F to -2*>F)

-2lOc to -31°C (-e°F to -24°F)

-37< c to -4e* n (-35*>F to -51°F)

-51°C (-eO®F)

-10°C to -21° (UF to -e**F)

-25**C to - 33®C I (-13°F to -27°F)I

-ЗТС to - 4в< С (-35°F to -51°F)

: -51 <4; ! (-eo T)

1/ From AH 70-38, 1 Ai uet 1979

SSiETKOD 502.3

1/ Corresponds to Severe Cold condition.

Method 502.3

502.3-a

during which the given teaperature ie equaled or eurpaeeed. For exanple, the 20 percent probability of occurrence of a teaperature of -SiC means that -51C or lower teeratiss шву ba expected tC cccvar 20 percent cf the hours dxsir.g the most extreme cold area cf titm world (excluding iyntarctieaj,

Low Teaperature Prot>abillty pf, Qecyrepgf -51°C 4/ (-00) 20X

-540c (-e5°F) lOX

-5т°е i-TlTf) Mb

-61°C (-78**F) IX

The 20 percent probability of occurrence is used for anst applications with noraml development cost considerations; however, other values nay be chosen to satisfy specific ailications or test requirements.

(3) wrldadde xssa with attended storage periods. If aateriel is to be stored for extended periods (years) withoiit shelter or protection in ar as that experience very low tenperatures. such as the cold pole of northeast Siberia or central Oreenland. there is an increased chance that the test item nay experience much lower tenperatures (approaching -es°c (-в5°П or less). Sxjch prolonged exposure to extreme low tenperatures can affect the safety of items auch as nutitions. life ацррогъ equipment, etc.

b. Duration of exposure to low temperatures. The period of tinm that the low-teaperatupe exposure exists may be a factor.

(1) Honharardous or non-safetv-related (non-1 i fe-support tvpe) eauiBaant. Most materiel in this category (in a nonoperating mode), with the poasible exception of organic plastics (I-2h and I-3.2b(2)), will not езфм>1 по* deterioration following tenperature stabilization of the teat item at low teaiMratu. Following teiqperatta< stabilization of the test item, a storage period of itnje hours will be used for this materiel if no other value is available.

(2) tplosive, puiitioiis. 9rBan49-P4tiey.j. These iteas may continus tc deteriorate fcllcwir.g tesperat\B>e stabi 1 isatien; e ssequantly, it is necessary to test them at low Umperatures for long periods of tine. A mininun storage period of 72 hours following tenperature stabilization of the test it n is reconnended. Since extreme tenperatures have existed for at least that length of time.

) 1-4 SPECIAL

1-4.1 Failts-e analysis. The failure of a test item to meet the requirements of the equipment specification oust be analyzed carefully, and related Information must be considered, sueb as:

a. nondestructive test/examination following exposure to low teaperature may be conduoted at tbe low test tenperatiire.

b. Degradation allowed in operating characteristics when at low tenperatures.

c. Neoassity for special kits or special cold-weather procedures.

d. Evidence of improper Itbricatlon and assurance that lijbriGants specified for tbe environamntal condition were used.

e. For starting failing on internal-confexjetlon engines, assurance of the presence of proper fuels and deicers, if appropriate.

f. Condition and adequacy of the power source.

1-4.2 PlUirr of test information reauired. The following Information is required in the test plan for adeqmte conduct of the tests of section II.

(3) Baatrainad ulaaa. Glass, ceramlce. and glass-typ pipoducts (such as thoaa \ d in optical systene. laser systens, and electronic systems) that require mowting or restraining in specific positions may experience static fatigue. A more extended period of low tenperature may be required to induce this phenomenon. A 24-bour exposure usually gives an 87 percent probability of uncovering this type of design defect.

c. Test item conf Kuration, Tbe configuration of the test item is an iaportant factor in how tenperature affects it. Therefore, the anticipated configuration of the test item during storage or \jse should be used during tbe test. As a BiiniBim. tbe following configurations shotild be considered:

(1) In a shipping/storage container or transit case.

(2) Protected or vnprotected.

(3) Deployed (realistically or with restraints, such as with openings that are normally covered).

(4) Mxlified with kite for special >lications.

d. Additional suidelines. Review the equipment specifications and requireamite documents. 1фр1у any additional guidelines necessary.

DETKX) 502.3

502.3-8

a. ТмЪ ppoc*dupe(0).

b. Test duration.

c. Test itam configuration.

d. Location of tenperature sensors (if required).

6. Test teaperattsas and tiim-versus<-teiiperstia data,

f. Additional guidelines. 1-5 References

a. AR 70-36. Research. DeveloDn nt. Test and Evaluation of

ifeterisl for EiCtreaB Cliaatic Conditior. 1 Aiust 1878.

b. mL-STD-210. CI initio Infomation ,to I>etennine Deaito and Test Reoureipntff for Military Systens and Eouipaant. 8 January 1887.

c. Svnopaes of BacksrourM Material for igL-P-210B. Climatic Extreme for

Military EauiPBsnt. Bedford. MA: Air Force Caate>idge Raseu Laboratories. January 1974. USIC n *r iy>-76Q-508.

d. НАТО STAHAa 2895. Extreme Climatic-Conditions and Derived Conditions for Oae.in , Defininjt Desisn/Test Criteria for MATO-Foreea Materiel.

14 ЛШт ivas

II-l АРРАВ ГО5

жшпшглч ело LOW TEMPERATURE SECTKW II

m, Tba required apparatus conaieta of a chantear or csablnet and auxlliaz inetrumentatlon capable of maintaining and continuously monitoring tbe required conditions of low tenperature throughout an envelope of air surroisxilng the test Item(s) (see General Requirements, 5.1.1a).

b. Air velocity in the vicinity of the test item shall not exceed 1.7 s/a (32S ft/min) wless Justified by the test item platform environment, to prevent unrealistic cooling (heat transfer) to the test item.

II-l.2 p9ntrols

a. Tenperature. Unless otherwise specified in the test plan, if any action other №m test item operatiMt Unjdtk as opening the chamber door) results in a significant change of the test item tenperature (more than 20 (3.вРП). Ibe test Iten will be restabillzed at the required tenperattsv before continuation. If the operational check is not conpleted within 15 mintites, reestablish tbe test Item tenperatis<e conditions before continuing.

b. Bate of t-esserat\jre change. Ibless otherwise epeo4fied= rate of tenperatwe change shall not exceed 3°C (6*) per minute.

c. Tenperattn neasrjrement. Tenperature sensor instrunentation Is required on or in the test item to establish tenperature stabiiiaation data.

Tagmerateupe recordin*. Contlnuota recordlnge of the chanber and test item tenperattire shall be made if required.

II-1.3 Test intems tion (See General Bequirements. 5.2.4)

a. Cndertest interruptions, tin interrition nidn alloia test teiqperatures tc fluctuate outside allowable toleranoes toward anbient conditlwis should be followed by a conplete ptloal inspection and operational check (where possible). If no problean are encountered, restablllze tbe test item at the test tenperatis<e and continue from the point of the interruption. Any problems should oonstitute test item failure, since no extreme conditions were enooisitered.

VETWD 502.3

502.3-е

Step 1. Instal 1 tenperature sensors in or on Uie test item as required to

deteira.ne the test item teaperatiS(8) .

Step 2. Insert the test iten into the chanber and stabilize the test item at standard aabient conditions (Qeneral Bequireamnts, 5.1a).

Step 3. (induct a conplete visual examination of the test Iten. with apacial attention to stress areas such as comers of molded cases.

Step 4. Poctssent the results.

Step 5. Prepare the test item in accordance th (ieneral Bequirenents, 5.2.2, and required test item conf iguraticm.

sitep 6. (knduet an oparational tooEOut in aooordanoe with the afved test

plan.

Step 7. Becord results for coaplianoe with Oanaral Baquirements, 5.2.1.

Step 8. If the test item operates satisfactorily, proceed to II-3. If not, resolve the probiems and restart at step 1.

Ifetbod 502.3

b. OvaFtegt. intmrTVptiOne. Any intmrrVptien that rwUlta in Пвг extrmv

exposure of the test itt than required the equipssnt specif ition should be fol lo Bd by a coKlate nmlcal axaad,natlon and №eratianal le ( i ere possible) before any continuaticm of testing. This is especially true where a safety problem could exist, such as with nxsiitions. If a problem is discovered, tbe preferable course of action is to terminate the test and reinitiate testing with a new test item. If this is not done and test item failxsre occurs during the remainder of the test, tha test results could be considered invalid becauM cf the overtest condition. If no problem has been encountered. reestabllA preinterrvption conditions and continue from the point where the test tolerances were exceeded.

II-Z Р^АВАТ1Ш pop

II-2.1 Prelialnsrv steps. Before initlatir.g any testir.g, detersina from the test plan:

a. Which test procedures are required.

b. The low-tenperature operation and storage requirements.

II-2.2 Pretest gtaRJffirJ ffwfrign checkout. All itess require a pretest standard anbient cieckout to provide baseline data. Conduct the checkout as folloiai (change of atep sequsnce may be required for large tost items):

lOL-STD-eiOE

14 JULY loee

11-3 ПОШ^. The following i> et procedwes, alona of in conbination, p>ovid the baaea for collecting the naceaeary infornatlon concerning the teat item in a cold anvircsBBsnt. Operational checkcjts should be ccndiicted after storage end after i!9inuiAti s to yerily aijceeaSful ooroletion of both ocedures. Proceed to the first test procedure aa determined from the test plan.

II-3.1 Procedure I - Storase

Step 1. adjust the test item to its storage eonfIgmaticn, and Install it in tha test iSasSssT.

Step 2. Adjust the chanber air tenperature to that specified in the test plan for storage.

Step 3. Following tenperature stabilization of tjie test item (Seneral Bequiremente, 5.1.3.1), maintain the storage traqperature for a period as specified in tha test plan.

Step 4. Conduct a visual examination of the test item and conpare the results with the pretest data. Record any pertinent physical changes or the fact that there were no obvious changes.

Step 5. If 1 сw-temperat-ura operation is required, proceed to 11-3.2: cthereiisa. proceed to step б belo a.

Step e. Adjust the chanber air tenperature to standard anbient and maintain mtll teaperature stabilization of the test item has been achieved.

Step 7. Conduct a conplete visual examinatim of the test ibem, and document the results.

Step 6. If wproprlate. conduct an operational checkout of the test item and docunnnt the results.

Step 9. Goopare these data with the pretest data.

II-3.2 Procedures II - Qparation

Step 1. With the test item in the test chanber, adjust the chanber air te>erature to the low operating tenperatxnre of the test item as sjiecif led in the test plan. Maintain uitil tenperature stabilization of the test item has been achieved.

St 2. Ccndiict as conplete a visual exasairiation of the test item as ciaaber access limitations will allow.

Step 3. Document the results.

MsmOD 502.3

CL-STD-SiCS 14 JUL7 ISSS

Step 4. Conduct an operational checkout of th* teat Item aa in 11-2.2, atep в. Step 5. Docunent the reault*.

Step 6. If manipulation of the teat item ia required at low tea >erature. prooaad to step 4 of II-3.3. If not, proceed to atep 7 ef this procedure.

Step 7. Adjust the chaaober air teiqperature to standard aiiiiant and aadntaln

uitil teaiwrature stabilisation of the teat it B has been achieved.

step S. Conduct a conplete visxial examnation of the test item. Step 9, Docueaent the result*.

Step 10. If appropriate, conduct an operational checdcout a* in II-2.2, step в. step 11. Docunant the results.

Step 12. Conpare these data with the pretest data.

II-3.3 Procejyre Щ - тг-УяХщМУП

Step 1. with the test item in the test chamber, adjust the ohaaker air tenperatxsre to the low operating tenperature of the test item, as deteradned from the

test plan. Maintain for two h0*s*s following t фerature tabiiisation of the test item.

Step 2. Wille maintaining the low operating tenperature, place the test item in its normal operating eonfigvn*ation by using the options of step 4.

Step 3. Rsestablish the teeperat\s to Utat teed in step 1, aove.

Step 4. Based on the tзфe of test chamber available, select one of the

two following options:

a. Option 1 - To be used lAen ai walk-in typm laaker is available: tSith personnel clothed and equipped as they would be in a low-tenperature tactical situation, disassenble the test item as would be done in the field, and repadk it in its normal shipping/storage container (a), tranait case, or other mode and

configuration.

b. Option 2 - To be used ftften small chaabers (non-walk-ln) are used: Parfona

the option 1 proeedtB, except that the dlsassainbly and pseuiing will be psrferssd Ъу personnel reaching through chassber access holes or the open doer ЬИе they* weiring heavy gloves stjeh as nuld be required in the natural environment.

ICTBOD 902.3

903.3-12

Opening of the сЬалЬег door may саше froet to form on tbe teat Item In addition to a gradual vmrmlng of the test item. Manipulation neceaeary to perform the required setup or teardo art should be limited to lo-minute intervals. bet iaen i hich the t6Щperatuгe of step 1 above should be reestabl ishsd.

Step 5. If operation of the test item is required at low temperatures, repeat step 2. above, and then proceed to step 1 of II-3.2. If not. proceed to step e of this procedure.

Step e. Conduct a conplete visual examination of the test item.

Step ?. Docussnt the results for cosparlson wlU) Ute pretest data.

Step 8. Adjust the chani>er air tenperature to standard ambient and maintain until tenperatxnre stabilisation of the test it n has been achieved.

Step 9. Conduct a conplete visual examination of the test item.

Step 10. Docissent the results.

Step 11. If appropriate, conduct an operational checkout of the test item as in II-2.2, step 6.

Step 12. Document the results.

Step 13. Сетрш>е these data Ath the pretest data. II-4 ШГОЯМКГКЖ ТО BE ЯВООНЮР

a. Test item identification (manufacturer, serial пгяюег, etc.).

b. Previovs test nsthcds to vtii the test lt B has been subjected-

c. Besults of each performance check, vlsiml examination (and photographs, if aillcable), and comparison with the failure criteria.

(1) Pretest.

(2) Dialing teet =

(3) Post-test.

d. Length of time required for eaeSi performance check.

e. Status of the test itea for each visual exasir.aticn.

f. Defects noted during visual examinations.