Comair, Inc.

The following comments are submitted on behalf of Comair, Inc. The first comment is to question whether the NPRM, as proposed, can supersede AD 2003-04-21. The current AD requires compliance of Bombardier Service Bulletin A601R-11-077 Revision A. This service bulletin not only requires installation of a new overwing exit placard depicting how the exit is to be removed, but also relocates the door weight placard, as well as, in some interior configurations, a “no baggage” placard, such as found in Part C of the above referenced service bulletin. This NPRM would require compliance of Bombardier Service Bulletin 601R-11-088 Revision A which only addresses the latest overwing exit placard depicting how the exit is to be removed. The compliance time appears to be based on the Transport Canada AD CF-2009- 02, which concurs with the recommended interval listed in Bombardier Service Bulletin 601R-11-088 Revision A. This compliance time seems unnecessarily excessive based on the simplicity of the required task. Nine months should be more than sufficient to procure parts, write work instructions and comply with the service bulletin. Additionally, based on the estimate of 664 airplanes of U. S. registry that would be affected by this proposed AD, nearly one-sixth of this 664 have already met the intent of this NPRM through an AMOC to AD 2003-04-21. Comair requested and received an AMOC to AD 2003-04-21 from the NYACO dated December 14, 2007 allowing the installation of the new overwing exit placards, part numbers S8388-1 and S8389-1. These are the same part numbers installed using Bombardier Service Bulletin 601R-11-088 Revision A. Comair completed installation of these placards on its entire fleet on March 15, 2008, over three months prior the initial release of Bombardier Service Bulletin 601R-11-088. Our instruction were simple, remove the existing placard; clean the surface with a clean rag and alcohol, install the new placard in the same location as the previously removed placard. Comair would like language in the final rule allowing credit for placards installed under the AMOC for AD 2003-04-21.