Aviator
Registered User
Canada (Legally)
This just in...
Date: Unknown
Location: Unknown
PA-18 departed on a routine flight; sky clear, winds light and variable, temp 71 F. T/O weight 1655 lbs. Take-off and climb to 800' AGL was normal and uneventful. 3 minutes after take-off, smell of burning electrical wire insulation noticed in cabin. Master switch was turned off, but smell continued and dense visible acrid smoke was detected. Door was opened to clear smoke, a farmfield was selected for landing. As the smoke began to clear, RPM dropped from 2300 to 2100, then within 5 seconds the engine failed. The forced landing was uneventful. The entire sequence of events took place in less than 2 minutes.
Post incident investigation revealed that the port side upper muffler surface split 5.125" along the (top) weld line, cracked, and folded up and forward exposing 5.125" x 1.75" of the muffler's interior. The shroud over the blowout area was missing. The exhaust gases (now directed up and toward the firewall) burned through both magneto grounding (magneto to firewall) conductors, effectively grounding both magnetos to the braided conductor shields. Generator conductor insulations were also charred.
After removal, the muffler was inspected. No evidence of previous damage and/or repair were found, the baffle was intact and secure, a bale had been welded into the tailpipe IAW AD and was secure. Other than the recent damage, the muffler was sound. The investigation continues.
S.F.
Nick
(I got this in an email I can't trace back, so I don't know any more about this incident. Maybe one of you mates knows more.)
See picture:
http://www.supercub.org/gallery/view_album.php?set_albumName=planes&page=2
Date: Unknown
Location: Unknown
PA-18 departed on a routine flight; sky clear, winds light and variable, temp 71 F. T/O weight 1655 lbs. Take-off and climb to 800' AGL was normal and uneventful. 3 minutes after take-off, smell of burning electrical wire insulation noticed in cabin. Master switch was turned off, but smell continued and dense visible acrid smoke was detected. Door was opened to clear smoke, a farmfield was selected for landing. As the smoke began to clear, RPM dropped from 2300 to 2100, then within 5 seconds the engine failed. The forced landing was uneventful. The entire sequence of events took place in less than 2 minutes.
Post incident investigation revealed that the port side upper muffler surface split 5.125" along the (top) weld line, cracked, and folded up and forward exposing 5.125" x 1.75" of the muffler's interior. The shroud over the blowout area was missing. The exhaust gases (now directed up and toward the firewall) burned through both magneto grounding (magneto to firewall) conductors, effectively grounding both magnetos to the braided conductor shields. Generator conductor insulations were also charred.
After removal, the muffler was inspected. No evidence of previous damage and/or repair were found, the baffle was intact and secure, a bale had been welded into the tailpipe IAW AD and was secure. Other than the recent damage, the muffler was sound. The investigation continues.
S.F.
Nick
(I got this in an email I can't trace back, so I don't know any more about this incident. Maybe one of you mates knows more.)
See picture:
http://www.supercub.org/gallery/view_album.php?set_albumName=planes&page=2
