Book excerpt: Static shear, fatigue shear, and compression tests were made on an aluminum honeycomb core material. Bending and compression tests were made on sandwich panels having this core material and aluminum facings. The bonds between the honeycomb cells of some of the core material were completely removed. The modulus of rigidity and the shear strength of the unbonded material were found to be about 70% of those of the well-bonded material. The compressive strength of the unbonded material is about 50% of that of the well-bonded material, which is consistent with the assumption that the compressive strength is proportional to the critical compression stress of the cell walls.