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To date three T-34s that do not have a
history of being flown in commercial air combat have been found to
have cracks in one of the "center section". Specifically, the cracks
have been found in the structure in the fuselage where the lower
fitting on the front spar attaches to the fuselage. See the pictures
on this page for an
idea of where this is at.
The three T-34s that have been found to
have cracks include:
BG-243
Jim Martin’s airplane, BG-243 with a total
time of 15,618 hours, showed anomalies at the # 8 and # 9 fasteners on
the forward left hand side of the center section. These fasteners will
also be removed and a bolt hole eddy current inspection performed in
the coming week.
BG-243 is the Lima Lima airplane that was involved in a fatal midair
collision on October 1, 1999. The collision occurred at about the
15,000 hour point. BG-243 was able to return to land, but the left
wing was so badly damaged that it had to be replaced. The damaged wing
was sent to Raytheon who inspected the forward and rear spars in
accordance with their Service Bulletin No. 57-3329. No evidence of
fatigue was reported.
GM141 (CCF 34-68)
From Tim Roehl, GAMI:
During the Main Spar Carry Through Surface
Eddy Current Inspection of the -31 inner channel on T-34A, S/N GM-141,
(CanCar S/N 34-68), it was found to have cracks at the #9
(inboard-most) hole location on the left and right forward locations.
Indications were of cracks between 1/4 and 3/8” long at the 12:00
position on the right side and the 12:00 and 6:00 locations on the
left side. This aircraft reports 8765 hours of total time and has no
documented history of ACM. These cracks were visually confirmed. These
fasteners, as well as certain adjacent fasteners will be removed for
bolt-hole eddy current inspection this week to determine the extent of
further damage (if it exists), i.e. whether the .125 thick outer
channel is also cracked at those locations. As unfortunate as these
findings are within our fleet, it affirms the validity and methods of
the inspection we are performing. It may even have saved lives.
G-166
Rod Daulton's T-34A, G-166, was inspected
on June 3rd with just under 5,800 hours Total Time by Jud Nogle at
Nogle & Black.
On the forward RH side at the No. 7
fastener we got a crack indication at approximately the 6 O'clock
position while performing the surface Eddy Current inspection. Using
the Eddy Current probe, we were able to observe the crack indication
from between 3/8 to 1/2 inch away from the fastener head.
We then removed the No. 7 fastener to
perform the rotating bolt hole inspection and were amazed at what we
found. The hole on the inner channel was elongated by almost 1/2 of
the diameter of the hole. The other side of the hole looks to be
fairly normal with no noticeable elongation.
With this information we called upon
Victor Juarez our DER for any thoughts or ideas. From the pictures I
took and sent to Vic (see below), his first opinion was that the
aircraft most likely suffered a "overload" at some point, so he
encouraged us to remove an adjacent fastener to see if it might be
similarly damaged.
We removed the No. 8 fastener and found a
perfectly normal hole, again I went back to Vic with pictures and he
and I are both scratching our heads trying to figure out how one could
duplicate these results. It has to be a manufacturing flaw, but we
just don't know how this could have happened.
The current plan is to removed the inner
"C" channel from the aircraft and fabricate a replacement channel,
assuming we don't find further damage in the outer "C” channel.
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