Action
Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.
Summary
We are revising an earlier proposed airworthiness directive (AD) for certain Cessna Aircraft Company (Cessna) Models 172R, 172S, 182S, 182T, T182T, 206H, and T206H airplanes. That NPRM proposed to supersede an existing AD that currently requires an inspection of the engine oil pressure switch and, if applicable, replacement with an improved engine oil pressure switch. Since we issued the existing AD, we have received new reports of internal failure of the improved engine oil pressure switch, which could result in complete loss of engine oil with consequent partial or complete loss of engine power or fire. The NPRM proposed to increase the applicability of the AD and place a life- limit of 3,000 hours time-in-service (TIS) on the engine oil pressure switch, requiring replacement when the engine oil pressure switch reaches its life limit. This action revises that NPRM by changing the applicable serial numbers ranges. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes. We are proposing this supplemental NPRM to correct the unsafe condition on these products.