This specification is for nonmetallic honeycomb core used in the manufacture of adhesively bonded sandwich panels for tactical shelters. Five types of nonmetallic honeycomb material are specified: type I - honeycomb for use in panels which are required to have a high load-carrying capability that could not be adequately met using any of the other type; type II - honeycomb for use in panels which are required to have a load-carrying capability that could not be adequately met by using materials of any of types III, IV, or V; type III - honeycomb for general use in panels where the higher performances of types I, II, and IV materials are not required; type IV - honeycomb similar to type II but with slightly lower performance; and type V - honeycomb similar to type III but with slightly lower performance. The density, honeycomb core shear, honeycomb core compression, honeycomb core cyclic aging, honeycomb core brittleness impact, flatwise tensile, and pH shall be tested to meet the requirements prescribed. The fungus resistance test, thermal resistance test, shear modulus test, core compressive modulus test, water migration resistance test, flame resistance test, and dimensional examination shall be performed to meet the requirements prescribed.

1.1 This specification is for nonmetallic honeycomb core used in the manufacture of adhesively bonded sandwich panels for tactical shelters. The materials are intended for adhesive bonding to aluminum facings using materials and processes defined by Practices E864 and E874 and Specifications E865, E866, and E990. This specification covers five main types of honeycomb for use in sandwich panels, Types I, II, III, IV, and V. Types I, II, and III honeycombs correspond to three honeycomb densities. Types IV and V are similar to Types II and III, respectively, but have lower performance requirements.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. For conversion of quantities in various systems of measurement to SI units, refer to Practice E380.

1.3 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.