1. AC 25.856-1X Thermal/Acoustic Insulation Flame Propagation Test Method Details

2. General: 1.Include Metric Units. 2.Sound damping materials? 3.Ducting?

3. Purpose: Applicability: Related Regulations & Documents:

4. Background: 1.Define thermal/acoustic insulation materials 2.Rogue sample? 3.Thinnest/thickest - minimize testing.

5. Test Sample Construction: 1.Question on cutting hole in film. 2.Tape unclear - # of questions. 1.Figures need improving 2.Need to say three strips. 3.Double sided tape? How? 4.OEM should test as installed?

6. 3. Hook & Loop. 1. All or only on insulation? 2. Need tolerances. 3. Adjusting height may change heat flux. 4. Show in frame. 5. How many tests? 6. Mated? - Unmated? 7. With each cover?

7. 4. Retaining frame size? 1. Diagram not clear needs dimensions? 2. How to test layered entities?

8. Test Conduct Considerations : 1. Test Melting vs. Burning unclear.

9. Applicability to Certain Materials & Installations: 1.Heater tape? 2.What about in occupied compartment? 3.What determines inside fuselage? 4.Def. Of thermal/acoustic insulation? 5.Size of small parts? 6.Testing with substrate when glued on.

10. Other: How will FAA ensure lab repeatability? Are there DER’S