3.1 This guide is intended for use by material suppliers, aircraft transparent enclosure fabricators, air-frame manufacturers, government agencies, and others that may become involved in the testing of transparency components. These test methods provide data on both individual materials and material combinations commonly utilized in the fabrications of aerospace transparent enclosures comprised of monolithic plastic, coated monolithic plastic or laminated constructions containing plastics.

3.2 Primary properties and their long term stability are critical to the performance of aerospace transparent enclosures. Property measurement tests define as-manufactured material properties of these materials. Aging procedures provide for exposure of parts or representative sections to environments that may induce changes in material properties as determined in property measurement tests. Property measurement tests performed before and after aging exposure provide a means of estimating the potential usable life span of a transparency or to compare the durability of one material with another.

3.3 When employing these test methods for comparison of materials for weathering effects the user should be aware that the many factors influencing degradation due to weathering vary from one location to another. For direct weathering comparisons, all material(s) should undergo exposure conditions and property measurements testing at the same time.

3.4 The test methods listed include those considered critical to the performance of aircraft transparent enclosures. Other test methods to evaluate materials may also be performed. Additional test methods are in preparation and will be incorporated. The user is advised to employ the latest revision of any test method.

3.5 The dominant component of all transparent enclosures is one, or more, rigid transparent sheet(s). The sheet(s) must permit the necessary visibility while providing structural integrity and protecting the aircraft interior from external environments as required by the specific aircraft design.

3.6 In its most simple form, the rigid transparent sheet may be the only component of a transparent enclosure.

3.7 When more than one rigid transparent sheet is employed, the sheets are laminated with a controlled thickness with either an air gap or with a transparent adhesive known as an interlayer.

3.8 Transparent enclosure designs may use multiple rigid transparent sheets to take advantage of specific properties of different materials. In this instance, there will be functions required of one of the sheets but not the other.

3.9 The test methods, practices and guides listed are a summary of the available test methods applicable to plastic transparent enclosures. They are presented in this format to simplify the search and to enable the user to determine if a method applicable to his requirements is available.

1.1 This guide is intended to summarize the standard test methods available on individual and composite materials utilized in fabrication of aerospace plastic transparent enclosures. As such, it is intended to specifically include transparent thermoplastics, transparent elastomers, and reinforced plastics, whether thermoplastic or thermosetting.

1.2 This guide is intended as an aid in the search for test methods pertinent to Aerospace Plastic Transparent Enclosures. It should be understood that all methods listed may not apply to all enclosures.

1.3 The standards included refer to the properties or aspects listed in Table 1. The properties or aspects are listed in alphabetical order and the descriptions used are intended to facilitate the search.

Property or Aspect

Test Method

Abrasion Resistance

D1044

Abrasion Resistance—Oscillating Sand

F735

Abrasion Testing—Sizing Sand for

C117

Bearing Strength

D953

Bird Impact Resistance

F330

Bond Integrity

F521

Brittleness Temperature—By Impact

D746

Chemical Resistance

D543

Coefficient of Linear Thermal Expansion

D696

Compressive Properties

D695

Electrical Insulating Material—DC Resistance or Conductance

D257

Electrical Insulating Material—Dielectric Breakdown Voltage

D149

Electrical Insulating Material—Dielectric Constant

D150

Electrical Insulating Material—Flexural Properties

D790

Electrical Insulating Material—Impact Resistance

D256

Electrical Insulating Material—Rockwell Hardness

D785

Environmental Resistance

F520

Exposure Apparatus Operation—Carbon ARC Type

D1499

Exposure Apparatus Operation—Fluorescent UV Type

G154

Exposure Apparatus Operation—Xenon ARC Type

D2565

Flow Rate

D1238

Glass Transition Temperature

E1640

Hail Impact Resistance

F320

Hardness—Barcol

D2583

Hardness—Durometer

D2240

Heating Elements—Detection of Flaws

F319

Ignition Loss

D2584

Impact Resistance—Falling Weight

D5420

Impact Resistance—Falling Weight (Polycarbonate)

F736

Index of Refraction

D542

Interlayer Material Selection

F942

Light Transmissivity

F1316

Luminous Transmittance and Haze

D1003

Optical Angular Deviation

F801

Optical Angular Displacement—Multiple Images

F1165

Optical Binocular Disparity

F1181

Optical Distortion and Deviation—Double Exposure

F733

Optical Reflectivity

F1252

Peel Resistance—Floating Roller

D3167

Rubber Properties in Tension

D412

Scratches—Intensity of

F548

Shear Strength—Fusion Bonded Polycarbonate

F734

Shear Strength and Modulus—Interlayer Materials

F1362

Softening Temperature

D1525

Specific Gravity and Density

D792

Specific Heat

D2766

Stress Crazing

F791

Stress Crazing

F484

Tear Resistance

D624

Tear Resistance—Initial

D1004

Tensile Properties

D638

Water Absorption

D570

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.