Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Notice of proposed rulemaking (NPRM).

We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD- 83), DC-9-87 (MD-87) airplanes, Model MD-88 airplanes, and Model MD-90- 30 airplanes. This proposed AD was prompted by a report of loss of airspeed indication due to icing. This proposed AD would require modifying the air data heat (ADH) system. We are proposing this AD to address the unsafe condition on these products.

View PDF