Sling Seat STC

[yukontools]

My 170B is in Fairbanks just finishing an annual. My mechanic had help from a guy to finish up my annual and the helper noticed the sling seat in the back. He went to look at the paperowrk on it as he thought it was a good and robust set-up. The paperwork showed that the stc was not proper. The "helper guy" holds that noted stc for a varied sling seat and it was not the one in my plane. Long story short........a mechanic in Fairbanks found an stc and put it in the paperwork before I owned it. I had the brackets for the seats removed so I was legal and could go bou hunting and will proceed to find an stc or look for a field approval this winter. Any thoughts out there?


Thanks.

Jon

[hilltop170]

Jon-
I have a complete (un-installed) sling seat installation designed by Wien Alaska Airlines and the 337 paperwork that came with it. I tried to post the documents here but this website didn't like its dimensions so wouldn't post them. I don't feel like modifying the documents so they will print here.

If you want to share info, PM me, maybe we can get something going.

[Roesbery]

I had a sling seat installed with a 337 dated July 13,1979. It was installed by Northland Aviation at Fairbanks. The specs ( Drawings etc. ) were by Bachner ( I think ) at Phillips Field ( Long since gone ) If I remember right the brackets for the ends of the upper and lower tubes and the brackets for the outer seatbelts were bought from Bachner's and the canvas sling was made by Alaska Tent and Tarp to the specs on the drawing. A block of hardwood was used as a spacer with the upper brackets. PM me with a address and I can send a copy of the 337 and new weight and balance which refers to the 337 but the 337 doesn't directly mention the sling seat????????? Just says: 1. This installation is exact duplicate of the one installed in Cessna 180-N9427C, Serial 31825. Approved on form ACA 337 dated 1956. 2. Weight and balance recomputed and entered in aircraft logs. It is signed by two A&P,s and a FFA Inspector Named Johnnie L. Wallace 7-13-79
There were a fair number of those seats around Fairbanks at that time. Yours may be that old also?????? Maybe someone can track down the 337 for that C-180????

[yukontools]

My mechanic called today and said that after exhaustive research it is noted in the logs that in 1958 the plane was recertified and at the time the plane was owned by the state of Alaska for trooper work it had the sling seat. It is noted with a w&b so the bogus 337 is to be removed. I am legal again with the seat in. Thanks though.

Jon

[hilltop170]

Jon-
Does that seat have an STC to make it legal?

[GAHorn]

I'm not certain what is meant by "recertified", but it might be informative to know that a "publicly owned" aircraft (a gov't owned one) does not need to meet the certification requirements of the type certificate.
In other words, depending upon whether or not the airplane was maintained/operated as a certificated design, or alternatively, if it were maintained/operated as a "public" aircraft, .... the logbook entry indicating that it was "recertified" may have merely meant that someone's actions were intended to return it to type certificated condition by a logbook entry. Such return does not prove that the aircraft meets it's type certificate....it only indicates that it might. Or it might not.

In a similar manner, and as an example, my airplane (N146YS) was never issued an original U.S. Airworthiness certificate . It left the factory with the tail number YS-146 and went directly to El Salvador. It did not need to meet U.S. certification requirements until the early 1970's when it returned through Florida for importation to the U.S. It was inspected for conformity and, despite that it had the wrong engine installed, it was issued a new U.S. Airworthiness certificate (in error, of course.) The inspector was a genuine FAA inspector (as opposed to a DAR) and his signature appears on the Airworthiness Certificate.
The error was not corrected until I bought the airplane and noticed that it had an O-300-C rather than any engine approved for the Type Design. I bought the STC directly from Ron Massicot (before he got unselfish and donated it to TIC170A), because in reality if any inspector took notice that the Airworthiness Certificate had been issued improperly (and despite the fact the FAA had actually issued it and signed it).... the airplane did not meet it's Type Certificate or any approved alternate. (The improperly issued Airworthiness Certificate was invalid. It would be similar to an improperly issued airman's certificate..... illegal to use the privileges thereof.... and REVOCABLE. The onus of operating that airplane illegally was that of the operator, - ME!)

It might be worthwhile to NOT take the easy path of accepting an unknown person's possible error, and re-examine the basis of approval for the seat. If it were a public aircraft (in the service of the Alaska Troopers) and if it were "assumed" to be a properly approved seat design simply because the Troopers had installed it (under their authority to disregard the Type Certificate), and if it were returned to private ownership in what was claimed to be a "recertified" condition, .... doesn't guarantee that the action was properly performed. I know. Been there. Done that.

Then again, it might also have been properly done. We don't know just yet what is mean by "recertified". I hope this helps explain these sort of matters a little.

[blueldr]

With all this publicity about less than completely legal sling seats in the back of Cessna 170 airplanes that this thread is giving out, it is bound to come to the attention of the new administrator of the FAA. Heads are going to roll!

[hilltop170]

With all this publicity about less than completely legal sling seats in the back of Cessna 170 airplanes that this thread is giving out, it is bound to come to the attention of the new administrator of the FAA. Heads are going to roll!

That's why my sling seat will remain safely rolled up inside of its storage bag in my hangar until I see an STC or recent field approved 337 that specifically applies to my seat. Then, I'll try to get mine approved for my plane.

I'm still hoping Jon/yukontools tells us if he or that mechanic helper has an STC or not.

[hilltop170]

I had a sling seat installed with a 337 dated July 13,1979. It was installed by Northland Aviation at Fairbanks. The specs ( Drawings etc. ) were by Bachner ( I think ) at Phillips Field ( Long since gone ) If I remember right the brackets for the ends of the upper and lower tubes and the brackets for the outer seatbelts were bought from Bachner's and the canvas sling was made by Alaska Tent and Tarp to the specs on the drawing. A block of hardwood was used as a spacer with the upper brackets. PM me with a address and I can send a copy of the 337 and new weight and balance which refers to the 337 but the 337 doesn't directly mention the sling seat????????? Just says: 1. This installation is exact duplicate of the one installed in Cessna 180-N9427C, Serial 31825. Approved on form ACA 337 dated 1956. 2. Weight and balance recomputed and entered in aircraft logs. It is signed by two A&P,s and a FFA Inspector Named Johnnie L. Wallace 7-13-79
There were a fair number of those seats around Fairbanks at that time. Yours may be that old also?????? Maybe someone can track down the 337 for that C-180????

Roesbery-
That is the exact same 337 and drawings I have.

Is there a drawing of the upper and lower support tubes or the sling seat web? I would appreciate a copy of those items if you have them.

[yukontools]

I will pick the planeup this week and will look at the paperwork. Iwill talk to the mechanic as well. Maybe I mispoke about re-certified. More later.

Jon