CESSNA 190/195 DOOR POST CRACKING
Upper door post cracking is one of the common problems with the 190/195. This problem seems to be slightly worse with the right posts than the left. (probably due to more flexing with the cutout for the entry door).
Most of the cracks we have seen have been in the upper curve areas with some around and between the upper hi-shear and bolt holes (see pictures below).
Actions to avoid cracks: 1) Dress and blend any rough surfaces in the bend areas of posts. This needs to be done prior to installation. 2) When installing, make sure posts fit together and against spar carry through flat and unobstructed prior to fastening and torquing bolts down. Follow correct torques for bolts and do not allow bolt to turn while tightening or installing. 3) John Collett, at Butterfly Aviation, has upper steel reinforcement plates available for door posts. 4) DO NOT drill any rivet holes or interior mounting screw holes in the bend area where these cracks mostly occur.
Many of these cracks are very difficult or impossible to see with posts and surrounding pieces installed in aircraft. The cracks around bolt holes below were only visible once bolts were removed. The crack in the right rear post was found only after front post was removed.
These areas should be inspected thoroughly prior to purchasing a 190/195 especially on aircraft with wing or gearbox damage history. To date, we are not aware of any catastrophic structural failures/Hull Loses, due to upper door post seperation, however, any cracking in a main structural member is strictly unacceptable. If anyone has any input or experiences to share, please send them to our e-mail address firstname.lastname@example.org.
Note; if reinforcement plates are used to repair a stop drilled crack (acceptable only in the parallel lip surface of the door post), the CFR's require follow up inspections to verify crack stability. Depending on whick post is cracked, this could be very difficult.