The International Cessna^® 170 Association

According to my parts manual, 170A S/N's 19092 and on show to have an extra rib 0332105 Fig 14-51. Mine doesn't have it and by my S/N, it should. I don't see any breaks in the TCDS at this serial number or anywhere else to lead me to believe there is anything different about the post S/N airplanes that require this rib. I also see that this rib is used on the 195's. No parts available from Cessna that I can find(Duh). I have made ribs before from form blocks and I suspect it can be done here also. I hate to rip my stab apart to make it legal, can anybody shed some additional light on this?

I wouldn't say it is not legal now as it is. Has anyone else told you it is not legal?

Is a parts manual a source for "required equipment" or "required configuration"? Is a parts manual a source for determining "legality"? It contains Cessna drawings and part numbers but I wonder if it still exists in the form of a controlled document that could be relied on for these purposes. Obviously, there are some parts that are only intended for one make/model and the parts manual is a good source of that information; but in this case, it doesn't sound as if that additional rib is unique enough that it would break the bank. It is possible that the empennage on this airplane may have been replaced long ago with parts from a Cessna 170A manufactured before the change. I doubt that this would be illegal any more than installing the newer empennage on an airplane manufactured before the change date would be illegal. I could very well be wrong, however. If you are concerned, you could ask Cessna or the FAA Aircraft Certification Office (ACO)in Wichita, KS.

Firstly....Keep in mind that you do NOT have a "parts manual". You have an "Illustrated Parts Catalog"....which isn't/was-never a manual. It is an un-approved document ...a Catalog...for identification and ordering parts....not for assembly instructions or for determining airworthiness. (It is a good guide...but not a controlling document.)

If you still want to add the rib, call Bill Milton at The 195 Factory, 518-882-6392, they have PMA approval and may have one in stock.

To all, Thanks for your answers

Jim