The International Cessna 170 Association

Ok, so I’m wondering why this is an issue for the OP. How hard can this be and it shouldn’t be hard at all. Cessna secondary seat stop uses a seatbelt strap to restrain the load of the seat and the pilot. In that case the seatbelt is secured to the floor and to do that there’s a doubler Cessna provides which is installed in the floor to spread the load. Again not Rocket science (if it was we could ask Miles for an out) so what’s the issue, the seat STC should spell out how the belts are installed. So I google the seat install and arrive at the website and oh- oh something isn’t right in my mind. I’m looking at two seat frames, humm I wonder how they are attached to the floor? I investigate a bit further, surely there must be more information until bingo ! It all makes sense.
Possibly the most famous sell statement in GA and the statement which is also the biggest curse. “ STC pending”.
To the OP, the only way you can install a seat other than the original install is with an STC and that STC would tell you exactly how to install each aspect of a new seat. There are rear seat options that have an existing STC.

Excellent detective-work Jim.
Also, as regards the secondary seat stop using an inertia-reel and material similar to a seat-belt: A major difference exists between the job of a seat belt and that of a secondary seat-stop in that the seat stop does not need to be concerned with a 9G decceleration loading. (At least not on my O300-powered airplane. Perhaps Green airplanes need 9G protection in the reverse-direction however.)

Thanks George, I’m not at Gary’s FBI like level, I’d like to think I’m more at Inspector Clouseau’s level.

There were directions to install. We found them. I have 4 hard points for tie downs: these were not used for the seatbelt installation. Just the seat center bolt and a sidewall attachment plate installed.

Great if you have 170 STC paperwork to follow, that’s good news, possibly they should update their website to increase their sales.

This might be a little late but this is how the rear seat belts attach in later model C180/185 and when the Kenmore C206 Middle Seat STC is used.

dogone wrote:I am putting an Innovation Airframe single rear seat in my c170. ...

In looking at their photos it appears that these seats are mounted quite a bit further forward than the original 170 rear seat. Will they accommodate more than young kids?

c170b53 wrote:Gary fair enough statement, but I think most would take a step back and look at the big picture. I think it takes a “ system “ to determine whether a plane is safe for flight.

Jim, I agree entirely. My comment about some obscure Service Bulletin that no pilot and maybe 1% of A&P's/AME's have ever read was meant tounge in cheek -- don't have an emoji for that. The more I study the 170 the more I realize how little I know. There is no way one person alone can be expected to guarantee the airworthiness of one's aircraft; in the words of Hillary, "It takes a village."

Hilltop and 258 That is exactly how my belts ended up installed. The seat is almost exactly as far forward as the original. I know it looks different but the tape measure does not lie.
Prop back on skis already on and should be in the air by end of next week.

dogone wrote:... The seat is almost exactly as far forward as the original. I know it looks different but the tape measure does not lie. ...

According to the TCDS these middle seats on the 180 are at 65". As a four seater the rear seat on the earlier 180's was at the same station as the C-170 -- 70". Good to hear you're going to be flying soon. That was quick getting the seats approved.