Why would it be more on the starboard right side?
I know the door is there but why would the wing get more stress? With a common 1-person occupancy there is more stress on the LH wing root than on the RH wing root, in turbulence.
Peter wrote:
I know the door is there but why would the wing get more stress?
Because you walk on the wing outside the door!
Peter wrote:
common 1-person occupancy
Perhaps not in high cycle training aircraft. And perhaps the constant climbing in and out is significant, especially in the negative direction? After all, the only significant flight loads these aircraft experience in their entire lives, where +`1g is considered a lot, is in the numerous repetitive heavy firm landings…
I can’t believe that walking up onto the wing is a significant stress, compared with the 1000-1200kg plane flying in turbulence which generates say 2g shocks (that’s 2x the aircraft weight, which is a lot more than a person’s weight).
A person walking up onto the wing is walking fairly close to the wing attachment point, which is also where flight stresses get transmitted.
But, regardless, if RH side failures are more common there must be a reason for it.
What is scary in this one is that this was a relatively recent exemplar of the Arrow. N106ER, a 2007 Piper PA-28R-201 Arrow III. They were doing circuits apparently.
A wing separation in a fairly normal flight mode is quite a different story than if it had failed in a high G or negative G maneuver. I reckon this will be a very thorough and fast investigation indeed.
Aveling wrote:
As a PA-28 owner this is of interest. I don’t know if it’s referred to in the other threads, but I’ve always felt that the AAIB’s commentary on the Thruxton crash Thruxton (Passenger behaviour, maybe camera strap caught on controls causing excessive control reversals) was a little ‘last resort’. It’s quite hard to apply excessive control forces in a PA-28 at normal speeds.
Sounds like a totally different failure, albeit with the same tragic result. The Thriuxton accident had a failure in download of the outer wing panel. That can happen at very high speed due to wash out but not sure if an Arrow wing would exhibit the same phenomenon.
NTSB preliminary says metal fatigue, no corrosion present.
Maoraigh wrote:
NTSB preliminary says metal fatigue, no corrosion present.
On a 10 year old airplane. Lovely….
An un-reported overstress incident? Not necessarily a manufacturer’s fault.
Similar fatigue cracks found in the other, attached wing. Same place. Must have been one hell of an upset to damage both wings in this fashion. Training aeroplane. Lots of hard landings?? The other really scary bit is that none of the external surfaces had any indication of corrosion/damage.