Y2Knit is collecting helmet liners until January 25.  They will be taken to Iraq by active duty Army Captain John Morrow, whose wife, Melissa, is currently living in Hagerstown with her parents while awaiting John's completion of his tour of duty.

Melissa has just completed her tour of duty with the Army (and has also just learned to knit!) and recommends that a simple stocking cap to go under the helmet would be the most useful.  She indicated that the helmets are uncomfortable so the padding as well as the warmth is appreciated. 

Helmet liners should be 100% wool for the warmth and wicking qualities.  Synthetic fibers are not as warm and will melt when exposed to severe heat in the event of exposure to fire. 

Y2Knit's basic hat pattern is ideal for a helmet liner that fits under the hat.   They should be black, brown, charcoal, tan, or olive drab as these are not part of the regulation uniform and need to blend with the helmet.

National programs for knitted and crocheted helmet liners also recommend the  following patterns:
Download knitted helmet liner PDF
Download crocheted helmet liner PDF