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Notice of proposed rulemaking (NPRM).

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD would require deactivation and removal of the vapor cycle system (VCS) installed per STC SA03674AT held by Premier Aircraft Services (originally held by DER Services) following DER Services Master Document List MDL-2006-020-1, Revision C, dated February 3, 2009; Revision D, dated April 22, 2009; Revision E, dated May 12, 2010; or Revision F, dated July 6, 2010. This proposed AD would also require revision to the airplane weight and balance. This proposed AD was prompted by reports of damage around the VCS compressor mounting areas found during maintenance inspections. We are proposing this AD to remove the VCS mount, which could result in the air conditioner compressor disconnecting in the engine compartment. This condition could result in engine stoppage or additional damage to the engine.

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