"Stronger-than-steel" Cockpit Doors Get FAA OK
When bulletproof cockpit doors are installed on U.S. airliners -- the rules say the doors must be in by April -- they may be constructed from composite materials. The FAA has certified Dyneema polyethylene fiber for use in the doors, which the manufacturer says is 15 times stronger than steel. The cockpit doors are slated for use by American Airlines, United Air Lines, Delta, Lufthansa, British Airways, and KLM. They will be used aboard Boeing 737s and 757s, various types of McDonnell Douglas aircraft, and planes manufactured by Bombardier and Embraer. Dyneema is manufactured by a gel spinning process by DSM High Performance Fibers, a company based in the Netherlands that operates a site in Greenville, N.C. Dyneema has a low density (it floats on water) and is highly resistant to abrasion, moisture, UV rays and chemicals. The high energy absorption of Dyneema makes it useful in bullet-resistant products, the company says. To meet the demand, DSM has more than doubled its Dyneema production capacity.