74-16-06 CESSNA: Amendment 39-1911. Applies to Models 177 (Serial Numbers 17700001 thru 17702041), 177RG (Serial Numbers 177RG00001 thru 177RG0445) and F177RG (Serial Numbers F177RG0001 thru F177RG0092) airplanes. \n\n\tCompliance: Within the next 50 hours' time in service after the effective date of this AD, unless already accomplished. \n\n\tTo prevent failure or chafing of the oil pressure gage line located between the firewall and the oil pressure gage, install clamps between the flap control cable and the oil pressure gage line in accordance with Cessna Service Letter SE74-2 dated January 25, 1974, or later approved revisions. Any alternate method of compliance must be approved by Chief, Engineering and Manufacturing Branch, FAA, Central Region. \n\n\tThis amendment becomes effective August 9, 1974.