hindsight2020
Final Approach
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- Apr 3, 2010
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hindsight2020
Final NTSB narrative finally available on an ex-coworker friend's fatal accident involving a power loss and impossible turn out of KABI more than 2 years ago. Not surprised with the usual belated and equally useless boilerplate from the NTSB, unable to figure out what caused the power loss, and blaming the pilot for attempting a turnback when it rolls snake-eyes. Not the scope of my question.
Specifically I was very troubled by the fact the adults were all ejected or partially ejected, while the infant remained in place. The front seaters died and the back seater (female) survived, along with the infant in the car seat.
From the report:
"The two front seat lap belt anchorages were adhesively bonded to the interior structure. The front seats and the inboard lap belt attachments and shoulder harness reel attachments were impact separated. Most of the fuselage shell around the front seat occupants had disintegrated into small pieces. The forward lap belt anchor locations consisted of large hex head bolts placed adjacent to the airplane structure with the fastener head covered with a generous mound of structural filler. On top of this filler the assembly was then covered with what appeared to be two four inch diameter circular wet-layup plies of glass cloth. The lap belt attachments were not otherwise mechanically attached. The shoulder harness inertia reels for the front seat occupants were anchored to the floor of the airplane and were not attached to the ceiling or the upper side of the door jamb. Both inboard lap belt attachments and both shoulder harness inertial reel attachments for the front seat occupants were impact separated.
The right passenger seat in the rear cabin was separated from its attach points. The left passenger seat in the rear cabin remained attached. The individual inertia reels for the two rear seat occupants were mechanically bolted to the top of a platform common to the aft cabin bulkhead, and both remained attached. The rear seat lap belt attachments were mechanically bolted through the adjacent fuselage for the outboard belts, and were bolted through the control cable tunnel sidewall for the inboard lap belts. The inboard lap belt attachment for the right rear occupant was impact separated and had pulled completely through the composite sidewall. The other lap belt attachments for both rear seat occupants remained attached."
So the rear seaters had half the lap belt attachment points bolted and thus were only partially ejected or not ejected; they were also the lightest occupants. The front seaters had none of the points bolted and the rest is history.
My question is: Is this right???? Baking in the attach bolts and slapping over more fiberglass? Jesus, please don't tell me this is standard build practices. The NTSB went further in criticizing other aspects of the bonding quality of the few remaining structural components large enough to inspect. The read left me with the impression they didn't seem too impressed with the QC of the lay and bonding job.
I'm a big fan of the exAB rules, but when I read some of this stuff, it really gives me the impression that defaulting to a skeptical approach of the airworthiness of an exAB resale is warranted in ways that are simply not in the same planetary orbit for certified. According to the report, the build was made by the deceased and his first one. He was otherwise a carbon copy of my demographic, pro pilot military IP with no prior experience in aircraft manufacturing. The report adds that he completed the build with the assistance of the factory. Of course under the presumption that they adhered to the "51% or more" rule, which I have no reason to doubt.
So for those in the exAB circle, what say you? Proper build practices, type-specific deficiencies of an obscure brand , hasty hack job by the builder that proved fatal, or somewhere in between?
Stay safe out there folks.
Specifically I was very troubled by the fact the adults were all ejected or partially ejected, while the infant remained in place. The front seaters died and the back seater (female) survived, along with the infant in the car seat.
From the report:
"The two front seat lap belt anchorages were adhesively bonded to the interior structure. The front seats and the inboard lap belt attachments and shoulder harness reel attachments were impact separated. Most of the fuselage shell around the front seat occupants had disintegrated into small pieces. The forward lap belt anchor locations consisted of large hex head bolts placed adjacent to the airplane structure with the fastener head covered with a generous mound of structural filler. On top of this filler the assembly was then covered with what appeared to be two four inch diameter circular wet-layup plies of glass cloth. The lap belt attachments were not otherwise mechanically attached. The shoulder harness inertia reels for the front seat occupants were anchored to the floor of the airplane and were not attached to the ceiling or the upper side of the door jamb. Both inboard lap belt attachments and both shoulder harness inertial reel attachments for the front seat occupants were impact separated.
The right passenger seat in the rear cabin was separated from its attach points. The left passenger seat in the rear cabin remained attached. The individual inertia reels for the two rear seat occupants were mechanically bolted to the top of a platform common to the aft cabin bulkhead, and both remained attached. The rear seat lap belt attachments were mechanically bolted through the adjacent fuselage for the outboard belts, and were bolted through the control cable tunnel sidewall for the inboard lap belts. The inboard lap belt attachment for the right rear occupant was impact separated and had pulled completely through the composite sidewall. The other lap belt attachments for both rear seat occupants remained attached."
So the rear seaters had half the lap belt attachment points bolted and thus were only partially ejected or not ejected; they were also the lightest occupants. The front seaters had none of the points bolted and the rest is history.
My question is: Is this right???? Baking in the attach bolts and slapping over more fiberglass? Jesus, please don't tell me this is standard build practices. The NTSB went further in criticizing other aspects of the bonding quality of the few remaining structural components large enough to inspect. The read left me with the impression they didn't seem too impressed with the QC of the lay and bonding job.
I'm a big fan of the exAB rules, but when I read some of this stuff, it really gives me the impression that defaulting to a skeptical approach of the airworthiness of an exAB resale is warranted in ways that are simply not in the same planetary orbit for certified. According to the report, the build was made by the deceased and his first one. He was otherwise a carbon copy of my demographic, pro pilot military IP with no prior experience in aircraft manufacturing. The report adds that he completed the build with the assistance of the factory. Of course under the presumption that they adhered to the "51% or more" rule, which I have no reason to doubt.
So for those in the exAB circle, what say you? Proper build practices, type-specific deficiencies of an obscure brand , hasty hack job by the builder that proved fatal, or somewhere in between?
Stay safe out there folks.
