I've been trying to find a photo of a Super Cub with a 3rd seat mod. I've looked over at Scub.org with no luck. Has anyone here actually ridden in a 3rd seat in a Cub? If not, has anybody at least seen one?

one of the cubs I fly has it, as far as I can see it consists of an extra headset plug and some paperwork.

Ccurrie, can the person who's sitting in that 3rd seat actually see out the rear window in a Cub with a stock window set up?

Honestly I've never actually used it I dont know anyone that would fit.

Honestly I've never actually used it I dont know anyone that would fit.

Because it's such a small seat/space back there?

Ya there is no seat in mine it looks exactly like every other cub back there

The 3rd seat mod that I have had experience with has an X brace welded under the baggage floor, seat belt attach tabs welded at the rear of the baggage compartment and the old rear seat back narrowed to allow the 3rd passenger to stick his/her legs next to the now middle passenger. There are no cushions or backrest unless you make something up as such. The 3rd seat is limited to 180 pound passenger but this also makes the baggage compartment now a 180 pound capacity. Probably the main reason you see many of them done is for the baggage capacity increase and not so much for the 3rd seat. I think I might have some pictures of the airframe I built that has the 3rd seat mod at the shop. I will look on Monday and see if I can dig any good ones up.

BTW this mod is only available on a standard cub and not on Ag models.... My Ag cub had a small jump seat in the baggage that my brother and I rode in when we were kids. Dad bought the Pacer when neither of us could fit back there anymore....

Brian.

I installed Ron Sullivans 3rd seat mod in my cub. Brian has it right on all accounts. It is an Xbrace, seat belt tabs , and a placard. The seat back mod is not part of the STC, but the only way you are going to carry a passenger with legs.

I have ridden in and flown cubs with three adults. It is doable, but not exactly a pleasure cruise... In a pinch it will get someone out of a bad place, but in that predicament a friend with a C180 would work better.

With the narrowed seat back, the third seater's legs become the middle seater's arm rests. To make the third seater a back rest you mimic the second seat rest, which is a square tube frame, with two dowels that pin into holes drilled in the floor board. the top lays against the lower aft piece of the headliner.

The best route for the mid seat, is to get the removable seat back cross brace STC also. This allows you to change seat backs by pulling two pins. Then have a narrow seat back made up for carrying a third pax. Some people actually leave the narrow one in all the time and prefer it, but I prefer the way the stock one blocks the road for things in the baggage area if there isn't a third pax. I also have an extra brace I keep with no seat back on it. Then I can fly with the back seat completely gone. Having an inverted dog leg ( IMHO another 'must have STC), and extended baggage, this will give you a full 6' of flat floor baggage...

Having said all that, the only reason I did the 3rd seat mod was to be legal, when my baggage was loaded... It's cheap paper that makes what you are going to do anyways, legal...

Take care, Rob

Found a couple of pics on my thumb drive....

The frame I was working on was from Airframes Inc. before they sold out. It already had the mod installed.
The photo's really do not show the mod itself but it is in the photo.

At the top left below the baggage door opening you can see the rearmost seat belt attach tab and part of the X brace.


This photo has the X brace covered with a piece of metal but you can see the 3rd seat and middle seat seat belt attach tabs. Side panels are Kydex


Brian.

FYI, the third seat mod came from the days when guides were hunting polar bears out on the pack ice. Because they were hunting a looooonnnngggg way out, operating on skis, and didn't have GPS (so couldn't find the same spot reliably--and the ice was moving to boot), they almost always flew two airplanes out on the hunts--one with the guide and hunter, the other with an assistant guide and a bunch of gas cans full of gas. When they found a bear, they'd try to find a place to land nearby, and guide would land. If that worked okay, they'd stalk the bear, kill it, skin it, pour the gas cans into both planes, load up and go home to Kotzebue, Wainwright, or....

If, on the other hand, the first airplane to land broke an axle or?? on landing, the assistant guide would find another nearby place to land HIS plane, land, pour gas in, and all three would board THAT plane and abandon the first plane to land, and fly home.

Those guys left a number of Super Cubs out there over the years. At one point, the FAA happened to be there when one of these "triples" landed and either a violation or a warning of one occurred and Ron Sullivan (I believe) created the third seat modification to keep the FAA happy. It was never designed to be used routinely.

Lots of Super Cubs out there in the Bering Straights, folks.

MTV

Good info. Brian, thanks for digging out those pictures. Rob, do you have a photo of the third seat installed?

Here's what I'm thinking. 75% of my flying is done solo, 15% with one other person and the rest with myself 5'9" 175, my wife 5'8" 140 and my son 3'4" and 40 lbs. I'm dying to own a Cub as I've become so addicted to my friends Cub. It's not in the cards to own my 182 and a Cub. I'm never going to haul my wife and son on a flight that's more than an hour in duration. Am I completely loco to think this is a doable thing? I've seen Cubs with rear windows that go pretty far to the rear of the plane, so it seems I could at least get him the visibility if that's the only issue.

PA12? Before you know it, your boy won't fit back there.

Pundy,

Yes, you're completely loco to even consider it, IF you will EVER carry your wife and your son in it.

I thought you were talking about wanting a seaplane? Cub with that load on floats couldn't carry any gas, except MAYBE a very light one with the 2000 pound GW. On floats, you screw up in ANY way, your little boy is waaaaaayyyyy back there in the back, and getting out of there is going to be really tough.

And, if not, your child WILL grow, and he'll grow out of that airplane in no time. Sitting in the baggage compartment of a Cub would be torture even for someone his size.

MTV

MTV The current owner says he gets off the water no problem with 400lbs of humans and 20 gal of fuel. The plane has the upgross to 2000. Should I be sceptical?

Pundy, don't put a kid way back there for safety's sake, especially on floats. Getting someone out of the baggage compartment of a plane upside down in the water - not worth it. Sitting back there cramped, with poor visibility, you're setting him up to dislike flying. A -18 is not a 3 person airplane except in an emergency.

Rhyppa wrote:Pundy, don't put a kid way back there for safety's sake, especially on floats. Getting someone out of the baggage compartment of a plane upside down in the water - not worth it. Sitting back there cramped, with poor visibility, you're setting him up to dislike flying. A -18 is not a 3 person airplane except in an emergency.

Exactly. And, if you're lucky, the child will GROW. In fact, most of them grow like weeds.

It's not a matter of whether the airplane will actually get off the water, it's a matter of safety and comfort. As Ryppa says, it you want to turn someone off from aviation, that would be a great place to start. Granted, a kid might think it's cool to begin with, but again, what are you going to do as he ages and grows? Start looking for another airplane, and use up 198 gigabytes of bandwidth trying to find the "ideal" replacement?

A 182/180/185 is a three place seaplane, and a great three place land plane. A Super Cub is not.

In my opinion, anyone who intentionally puts someone in that third seat in a SC ON FLOATS (except in a situation that's basically an emergency or about to become one) should have his pilot privileges restricted to "no passengers". Getting out of an upside down seaplane is difficult at best. Trying to do so from the baggage compartment of a Cub would be a nightmare.

MTV

To get a cross section of responses I posted this over at SCub too. The replies there are not nearly as negative. I promise you I'm not looking for trouble here, just curious to see why here at BCP it's considered such a poor idea (other than the seaplane aspect) and at Scub there are those that say "Completely doable and I have seen it done on a regular basis in the exact same scenario as your's." Thoughts? Are they just crazy Cub pilots with an overeager opinion of their beloved planes?

Just my 2 cents, but i have a Cessna 140. I tried to entertain my daughter in the jump seat, and she was miserable. The vis was poor, and the air circulation left something to be desired. Mind you, this is a kid that loves flying, aged 10 now. She was 7 or so then. We are in Texas, so the heat is more of an issue than for some. I would think being back there would be no fun, and based purely on reading, difficult to get out of in an incident. I'd think twice before doing it.

KB

Pundy,

On SC.org, you have not been looking for an airplane to put on FLOATS, which you have here. I've been flying and around Super Cubs a LOT for over 30 years now, and I can't recall seeing more than one person in the third seat of one ever. It happens, no doubt, but go LOOK at that "seat".

As I pointed out earlier, this was a mod designed to keep the FAA happy during the polar bear hunts years ago, and to keep these guys from getting cited in the process. They carried a fair number of guides back in those days, because the alternative was staying out on the ice, with no hope of rescue.

Almost everyone installs the third seat conversion in a cub they're rebuilding these days, but not so they can carry a passenger in it--it's so they can get a 180 pound baggage compartment.

MTV