Can O-2 doors be removed?
 

I thought I saw this mentioned, but I haven't found confirmation.

Two questions:
Can O-2 doors be removed without tools?
If so, is there an STC to put O-2 doors (or O-2 door hinges) on a pre-73 skymaster?

Yes O-2 doors will fit the early birds. Several have done it

An example of a form 337 to put an O2 door on an early 337.

https://i.imgur.com/l8XFWKi.jpg

Thanks! Do the two hinges specified in the 337[form] have a pin so the door can be removed without tools?

I don’t recall offhand. I think they are similar to the regular hinges, just a heavier duty pin than the civilian birds. I’ll get to the airport Monday or Tuesday and double check. The mod was made years before I got it. I’ll bet Don Nieser at Commodore could sell you everything in one go if needed. He probably knows a bunch of different ways to do it too.

RT Aerospace has the STC SA00409AT

The hinges will match but the door locking mechanism is totally different. They use Carter key pins that pull right out

02 on T337C
 

Got the O2 door from Don Neiser In OK, and then the STC from Ray Torres at RT Aerospace.

Don (when selling the door) said it would just slap right on...when the IA doing the install had issues, Don said it takes a lot of finessing :)

so, it does work, and I get TONS of compliments on having the O2 door with glass all the way down....but be prepared for some work to 'fit' it into place.

you will like it in the end.

couple of other notes -
-- if you don't want to install the wind shield part of the STC, you can do it and Ray will sign off, but that voids opening the window in flight (O2 door has a cool window that cranks out)
-- there is no 'key' lock on the door...it has a clasp that you put on a physical padlock...I use a lock that has alpha characters on it, bot you could put a basic key padlock as well.

Mine don't come off with a pin like the ones on my 185. I you are looking for one with O2 doors I do have one for sale.

https://www.wefly4u.com/n1275m

Ed

The O2A door is jettisonable
 

The O2-A door is jettisonable so the pilot can bail out (flight manual says jump out and down so you stay clear of the strut).

A jettison handle just forward of the door is attached to the two door pins via cables. It is on the preflight checklist.

STC needed
 

You may not need an STC, just a field approval. If you can install all the associated door parts for the O2-A as shown in the parts manual, the logic flows that the Cessna engineering data is inherent in the installation. All the other required information for the field approval is in the military info. eg instructions for continued airworthiness, etc.

0-2A door
 

Jim, call me. I have brand new 0-2A doors in stock with all the information and R.T. Aero's STC to install an 0-2A door on your early 337. The new 0-2A doors i have, have a new window and crank assembly the opens the window up to the horizontal position and you can fly with the window open to 122 kts.
Don Nieser
Commodore Aerospace Corp
405-503-4686