Natick Letter with Changes.pdf

This is a memorandum from the U.S. Army Natick Soldier Center detailing preliminary changes to Helicopter Sling Load (HSL) Training Blocks, dated August 13, 2005. The document outlines modifications to the HSL Training Block data package and specifies requirements for a new 4000 lb training block.

The key changes include replacing 440C Stainless Steel with 1018 or 1020 Cold Rolled Steel for Lift Eyes, adding cadmium or zinc plating for corrosion resistance, and dividing Lift Eye Plates into two separate plates for better alignment. For the 4000 lb block specifically, the requirements include: reducing length from 138.5 to 95.0 inches, marking sides with 8-inch high "4000" in black paint, reducing reflectors from 22 to 16, reducing lateral/vertical rebar loops from 23 to 15, and leaving the concrete in its natural color without dye. The document includes detailed technical drawings for lift eyes of various load capacities (1500 lb to 22000 lb) and specifications for the 4000 lb training block construction. Testing requirements specify proof load testing at 14000 lb (3.5x load factor) for 90 seconds.