Rear Seat Removal

[c170b53]

In my last reply, I thought it best to say as little as possible but oh heck here I go. I think most people see the real issue here. The rear seat is removed to carry cargo but how do you safely secure that cargo? That's the issue. If you want to turn you plane into a Combi / Freighter, what hold down points will you use? Obviously by using the forward seat attachment points as anchors for a net, it's easy to creat a forward restrain wall but how do you crate an aft wall when there's only one hold down point? To be a real cargo tie down point the structure would have to be reinforced and tied into structure more significant than the floor skin.
And yes if after reading this, you may be thinking it must be raining in YVR again.....everything is Ireland deep green.

[Bruce Fenstermacher]

No Jim that is definitely NOT the issue. You do not have to remove the seat to overload the aircraft. Whether the seat is in or not makes no difference. In other words not allowing the seat to be removed because having it installed is a safety feature which restricts one from overloading the aircraft is wrong.

Fact of the matter is I might want to fly my airplane without the weight of the back seat and have no cargo more than I could otherwise carry with the seat.

[c170b53]

O.K Bruce ( sorry I've read you post more than once and not sure what obviously I've missed) each to their own but the only reason I'd remove my back seat is to put something bigger in that space. I guess if you didn't have a back seat, thought that 30 odd pounds less would make a critical difference in performance, wanted to save bit in fuel or all along only wanted a two seater then it's not a problem. But those amongst us that want to carry large objects in the back there is a obstacle. Overloading the plane? Never done it...er maybe very very close. Removing the seat so you can carry more load? Sure but I'm thinking 30 lbs one way or another including fudge factors wouldn't prompt someone to go through the ordeal. Having an aft C of G is a killer or overloading is a bad idea period and I'm sure we all agree there. What I'm saying in my last post is (at least in Canada) if you have objects in the back they must be properly restrained. If I carry my bike in the back, I must strap it down. If I'm caught without restraining my cargo by team TC, it's like getting a parking ticket; it's issued in the same demeanour and good luck trying to get out of paying the fine.
Lastly I like my seat in most of the time. With it in any light items like sleeping bags, tent and such are trapped in the cargo bay with the seat back against the hat shelf. I load our bags, map bag and the must have munchies on the rear seat such that either of us can easily get at them during the flight.
I'm no small weight nor is my plane and with big tanks my useful load isn't as much as I would like. Last week I took a fellow worker on a ride in search of pie. I love this guy, everyone likes him especially if they need some power, he is a fantastic worker and he has been affectionally nicknamed "Rhino". I didn't ask him what he weighed but i'm guessing that flight was one of those very very close GW ones, I'm just glad we didn't break a seat back.

[48RagwingPilot]

FWIW, I took the rear seat out of my '48 C170 at the last annual (12/12), with my A&P/IA's blessing and a logbook entry. Am also carrying a revised weight & balance. I ran around for years with the same configuration in a C182 and then a C180 and never had an issue with the FAA, even through one ramp check and several field approval inspections. Not saying that makes it legal. As for securing cargo, I was able to modify the Mountain Wave Aviation cargo net from my C180 to fit my C170 and it should work well for camping this summer.

[Bruce Fenstermacher]

Jim, you may have understood my point before so bear with me because I think it is important that we not confuse the issue. A pilot is responsible for the safe operation of his aircraft which includes operating it within all limitations regardless if the rear seat is installed or not. So including a discussion on how one would secure cargo clouds the issue and has no bearing on what kind of alteration rear seat removal is with respect to the 170.

Again forgive me for being repetitive in my posts.

Sure I agree it is probably easier to exceed a limitation by overloading your aircraft without the rear seat with a large heavy object, but I've seen more aircraft overloaded beyond limits with all seats installed.

My partner likes having the rear seat removed because he can't carry a third person. No he doesn't have to take a third person if the seat is installed but he doesn't like having to tell a person he doesn't want them in the back.

[c170b53]

No sorry I guess I'm not fully explaining. I'll try another tack here. I'm not talking W&B. If someone overloads their airplane, I'm guessing they probably know the risks. There are many reasons people are flying with the rear seat removed. Myself, it allowed me to carry bikes.
If the rear seat is removed, it really means you can't have anything in the plane aft of the front seats. If that works for you great but I think most remove the seat to put something else back there. Not everybody but certainly a few. And now the problem; it doesn't matter whether there's a dozen Kleenex boxes or a dozen bricks being transported; it's cargo and it must be secured. How?
My XP has floor hold down points from the factory to attach a cargo net so no STC required there. My 170 doesn't. So as in my earlier post, I see no problem removing the seat and I still don't. I see a problem of putting something back there if its out.

[blueldr]

I no longer have the '52 B Model that for years had no back seat installed. That airplane had, in addition to the seat hold down nut plates in the floor and side wall, a number of other floor mounted nut plates in which I had installed tie down rings for securing cargo. The nut plates for the all of the seat mounting bolts were also equipped with tie down rings for that purpose.
I don't remember what the extra floor mounted nut plates were originally meant for, but I seem to remember them as being factory installed for some purpose. They did provide very useful extra tie downs, and I never had any reason to be concerned about cargo security.

[bagarre]

I don't remember what the extra floor mounted nut plates were originally meant for, but I seem to remember them as being factory installed for some purpose. They did provide very useful extra tie downs, and I never had any reason to be concerned about cargo security.

There you go mixing common sense and the FAA again

The issue isn't if we CAN do it, it's if we MAY do it. And that has little to do with anything other than the opinion of the person you're talking to

[Bruce Fenstermacher]

To Jim's point, there is very little to assist in securing cargo with or without the seat besides putting 120 lbs behind the seat if installed and hoping the seat back holds the cargo. Of course maybe you could secure 120 lbs of cargo to the seat with the seat belts but that is often easily said but not well done.

With the seat removed Cessna sold cargo attachment rings for the seat tracks which can be used at the very back of the front seat rails. Rings could be screwed into the side seat mounts and one in the center of the floor at both the front and back seat attach points. Of course other attach points besides these could be added.

[lowNslow]

I no longer have the '52 B Model that for years had no back seat installed. That airplane had, in addition to the seat hold down nut plates in the floor and side wall, a number of other floor mounted nut plates in which I had installed tie down rings for securing cargo. The nut plates for the all of the seat mounting bolts were also equipped with tie down rings for that purpose.
I don't remember what the extra floor mounted nut plates were originally meant for, but I seem to remember them as being factory installed for some purpose. They did provide very useful extra tie downs, and I never had any reason to be concerned about cargo security.

I have these same nut plates on my '53 as well and assumed they were for the "cargo tie-down lugs" in the parts manual. I wonder what Cessna was thinking you were going to use these for if you can't remove the rear seat.

[voorheesh]

I need to provide an additional part of FAA Inspector David Jensen's comments to me last week. David and another inspector at his office believe the rear seat is tied into the type design by virtue of its description in theTCDS. He believes that Cessna would have labeled it optional if they intended for it to be removed. Of course others believe that Cessna would have labeled it required if they intended installation to be mandatory. That is why we are seeking an opinion from FAA engineers. It would be unfair to unilaterally dismiss David's opinion in this question because he based it on his office's guidance and he offered it in a sincere effort to answer an airman's question. He did not say it could not be removed, just that it would be a major alteration. Again, this is but one example of many issues that result in different opinions from various FSDOs and we should be aware that the FAA is seeking to address the problem while respecting the experience and background of its employees.

[blueldr]

In my recollection, there were four or six extra 1/4 x 28 threaded nut plates in the floor of my airplane in a rather rectangular pattern, the rearmost two of them being well to the rear of the baggage area but just ahead of the bulkhead.
Cessna must have had a reason for installing them and I can't imagine them having any use with the rear seat installed.

[GAHorn]

Just because you have found "four or six" nutplates mounted in the floor of your Cessna 170....doesn't mean Cessna put them there. Or that they are intended for securing cargo. They may have been intended for tying the dog's leash.

It's possible they were placed there by someone else and never entered into the mx logs or equip't lists. (In which case they should be documented or removed.)

[lowNslow]

Just because you have found "four or six" nutplates mounted in the floor of your Cessna 170....doesn't mean Cessna put them there. Or that they are intended for securing cargo. They may have been intended for tying the dog's leash.

It's possible they were placed there by someone else and never entered into the mx logs or equip't lists. (In which case they should be documented or removed.)

While that is possible, the ones I have were riveted to the underlying structure with no rivets showing through the flooring which means they had to be installed before the flooring. That and the fact that I have seen several 170s with the same nut plates in the same locations seems to point that these were factory installed.

[GAHorn]

There are two nutplates installed at the rear of the bag floor (Items 60), and two at the rear spar bulkhead. (Items 34)

Is that where you found them?

Nutplate.JPG

Nutplates 2.JPG