Wing Centreline Splice Joint 6/2003
Applicability: Models AT-300, AT-301, AT-302, and
AT-400A aircraft, all serial numbers, that
have aluminium spar caps; Models AT-400 aircraft, serial numbers
400-0244 through 400-0415, that have aluminium spar caps; Models
AT-300 and AT-301 aircraft, all serial numbers, that have aluminium
spar caps and are, or have been converted to turbine power. Accomplish either the Requirement 1 spar lower cap
replacement or the Requirement...
2 spar lower cap repetitive inspections.
Repetitively inspect the wing lower spar caps instead of
Replace the wing spar lower caps before further flight after
whichever occurs first:
(i) The date of the scheduled replacement;
(ii) Cracks are found during any inspection allowed by Requirement
2 of this Directive; or,
(iii) Upon accumulating 600 hours time in service after the initial
accomplished in accordance with Requirement 2.b. of this
This Amendment becomes effective on 7 May
Background: The FAA received a report of an in- flight separation
of a wing from a Model AT-400A aircraft. Investigation revealed
that fatigue caused the lower aluminium spar cap to fail across the
3/8- inch hole, 6.5 inches outboard of the fuselage centreline in
the centre splice connection. The actions specified in this
Directive are intended to detect and correct cracks in the
centreline splice joint. Undetected cracks could eventually result
in in- flight separation of the wing. Amendment 1 is issued in
response to a new FAA AD which further reduces the mandatory wing
spar lower cap replacement times; in response to inspection results
from FAA AD 2002-13-02.
The original issue of this Airworthiness Directive became effective
on 24 July 2002.