Cessna 172 Tailcone Stringer

[soldanr]

I have noticed that Cessna designed the 172 D thru 172 I models without a tailcone stringer. I have found some of the K models without a tailcone stringer also. The stringers are 2 J-section that sits on the bottom / side and an L-Extrusion that is located int he middle. Also I have notice that some of those stringers vary on thickness, some of them are .032 and some of them are .051 thick. I know cessna started to add stringers in the L / M model, with a gross weight increase. I know that the stringers are linked to the gross weight increase in some models.

I am just trying to find the history (soap opera) behind the Cessna 172 stringer engineering in those aircraft. Wich airplanes were equiped with a .032 stringer, and wich were equiped with a .051? Did they have a different GW?

If anyone has knowledge on this matter please let me know your 2 cents?!

Have a great day!

 

[Sparweb]

I don't have a definitive answer for you, but I would start my search in the Illustrated Parts Catalog for the 172's. You might find the part numbers and effectivities for a series of parts, and then all you would have to do is find the planes you need - those that contain different part #'s - and measure what you need. Say (for example) you can find and measure up a 172F model, and the part effectivity is from "D" to "I", you can then assume that the "D"s thru the "I"s are the same as the one you measured.

A 0.032" stringer would likely have a different P/N than an 0.050" stringer. Gross weight increases can be tracked through Type Certificate Data Sheets, available from the FAA website.

I've not dug too deeply into 172 IPC's myself, beyond a job on a wing and another on a door frame, so I can't say how comprehensive the book will be. There is a possibility that finding an older IPC would reveal valuable information on the earlier models (in case newer books don't contain that information any more - but I doubt Cessna would do that).


Steven Fahey, CET