68-11-01\tBOEING: Amendment 39-605. Applies to Model 707 Series airplanes equipped with Collins Model 51RV-1 navigation receivers and Pratt & Whitney P/N 563586 or General Laboratories P/N 42721 solid state engine ignitor systems. \n\tCompliance required as indicated. \n\tReports indicate a localizer course indicator error may exist when the Pratt & Whitney P/N 563586 or General Laboratories P/N 42721 solid state engine ignitors are turned "ON". Since this unsafe condition is likely to exist in other Boeing Model 707 Series airplanes, the Director determined that: \n\tA.\tFlight operations shall not be predicated on the use of localizer receiver information when engine ignition systems are "ON". \n\tB.\tThe operating limitations specified in subparagraph A of this paragraph must be placed in the aircraft in the form of a placard in clear view of the pilot. For purposes of this AD any documents including a pilot check list including these limitations constitute a placard within the meaningof this paragraph. \n\tC.\tThis limitation does not apply when a 1000 microfarad 50 volt capacitor has been installed across the 28 volt DC input lead to the Collins 51RV-1 receiver in the radio junction box in accordance with Boeing telegraphic Alert Bulletin 2752 dated May 10, 1968, or an equivalent suppression system approved by the Western Region Aircraft Engineering Division. \n\tThis amendment becomes effective on May 31, 1968, for all persons except those to whom it was made effective immediately by telegram dated May 10, 1968.