Safety Recommendation
The Australian Transport Safety Bureau recommends that the
Aviation safety Authority of Sweden (Luftfartsverket) assess the
safety benefit of mandating Saab Aircraft AB Service Bulletin
340-24-026 incorporating generator control unit modification number
2533.
The Aviation Safety Authority of Sweden (Luftfartsverket)
advised that they issued Swedish Airworthiness Directive (SAD)
number 1-196 R1 on 7 July 2004.
That airworthiness directive requires a repetitive inspection of
brushes fitted to Saab 340 DC generators overhauled in accordance
with MRB Task 243104. This action is to be conducted until
terminating action, scheduled for October 2004, had been
defined.
ATSB Note: The airworthiness directive is an interim measure until
an improvement is mandated. The ATSB will monitor the response
until the termination action is completed.
The Aviation Safety Authority of Sweden (Luftfartsverket)
advised that they issued Swedish Airworthiness Directive (SAD)
number 1-197 effective from 5 November 2004. That airworthiness
directive requires:
(a) Installation of a Generator Control Unit (GCU) model 51539-007B
in accordance with Saab Aircraft AB Service Bulletin SB 340-24-026
Rev 2 dated 29 October 2004 or later revision.
(b) Continuation of brush inspection and wear measurement in
accordance with Service Bulletin SAAB 340-24-035 Revision 1 dated
10 September 2004 or later revision until the new GCU is
installed.
The new GCU must be installed within three years after the
effective date of this SAD.
