COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters AD/BELL 206/94 Auxiliary Fuel System - Modification 3/83 Applicability: All models with Chadwick C-22 auxiliary fuel system installed per supplemental type certificate SH139WE. Requirement: PART 1: Install placard readily visible to the pilot in the cabin with the following annotation:- WARNING "USABLE AUX. FUEL LIMITED TO HALF AVAILABLE QTY. AT T/O" PART 2: Install Chadwick C-22-FM flow monitor kit. Note: FAA AD 82-16-12 and Chadwick SB20-81-01 refer. Compliance: PART 1: Within 10 hours time in service after 22 February, 1983. PART 2: Within 300 hours time in service, or 6 months after 31 March 1983. The placard installed as per Part 1 above, may be removed, provided the revised flight manual supplement, Chadwick Auxiliary Fuel System C-22 dated 21 October 1981, is incorporated into the rotorcraft flight manual. Background: Tests conducted by the auxiliary fuel system manufacturer have shown that the loss of one auxiliary tank fuel pump will result in only half the usable auxiliary fuel being available in flight. When such a failure occurs, no warning is provided.