COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Airtractor AT-300, 400 and 500 Series Aeroplanes AD/AT/14 Never Exceed Airspeed Limit 8/92 Applicability: AT-302 all serial numbers, AT-400 all serial numbers, AT-400A all serial numbers, AT-402 all serial numbers up to and including 402-0784, AT-402A all serial numbers up to and including 402A-0782, AT-502 all serial numbers up to and including 502- 0118 and AT-503A all serial numbers up to and including 503A-0067. Requirement: Re-mark the Vne (Never Exceed Speed) `red line' radial marking on Airspeed Indicators as follows: 1. 119 kts IAS for AT-302, AT-400, AT-400A and AT-402 and AT-402A aircraft. b. 133 kts IAS for AT-502 and AT-503A aircraft. Markings above these speeds should be removed from the indicator. Note 1: Snow Engineering Company Service Letter 91 refers. Note 2: Appropriate Flight Manual amendments reflecting the revised Vne will be issued in due course. Compliance: Before the issue of the next Maintenance Release or 31 October 1992, whichever occurs first. Background: This Directive is issued following a re-evaluation of the propeller certification data by Hartzell. Compliance with this Directive provides the pilot of the aircraft with an indication of the aircraft's upper airspeed limit, which if exceeded, will cause the propeller blades to be subjected to unacceptable stress levels.