I'm a partner in a '69 Twin. The interior was replaced by a different owner a number of years ago and rear passenger air vents are no longer in the airplane. Is it possible they were never there? Do any others out there have missing rear air air vents? Anyone have thoughts about what it might take to replace/add rear vents?
Thanks in advance for any responses.

Hi Herb,

I've recently replaced the headliner in my twin which is a '68 "B". The rear vents were in bad shape and, of course, replacement parts were not available. I found a suitable part from Aircraft Spruce but needed to have a machine shop make a mounting plate for the new vents. Your '69 should have the mounting structure as part of the cabin roof, but is likely covered by the headliner. Without the vent in place, ram air from the dorsal pick-up would probably be visible as a bubble in the headliner material if the tubing connecting it were still there. My new wool headliner developed a dark spot where the vents should have been mounted. There are a couple of things I'd suggest if you're uncertain as to the connection to the dorsal. Remove the access panel to the tail section in the baggage compartment and see if there is tubing running from the dorsal forward to the overhead vents. If that's in place and not blocked off, then try removing the window trim (passenger side is easiest) and peel back the headliner material to expose the vent connection. It's possible that you may have to remove the retainer frame for the side window if your headliner material is glued beneath it. If all is intact, make a templet with screw locations etc. You may find it useful to use double back tape to reattach the headliner material. You can find a vent at this link: http://www.airkitllc.com/vents.php . These can be ordered from Spruce as I mentioned, but you'll need and "owner produced" mounting plate or adapter to install them.

Good Luck
David Miller