Franklin 220 in a Supercub

I could not believe my eyes, there it sat on the tarmac, cowls off, and yes a 220hp Franklin bolted to a supercub (experimental I'd guess). There was no one around and no one seemed to know anything about it. If that tail shakes with a 180 Lycomming..... hmm,,, "lets do the twist again". Big gear and tires, its about all I could tell. Was gone when I came back, likely striaght up. Anyone heard of this sort of thing?

220hp

Thinking about this, I should have posted it under wieght and balance, seems that Franklin is heavy and long.

Here is the franlin website, the 220 does not appear to be STC'd for the cub yet.

http://franklinengines.com

No I can't imagine the STC for this one. It was certainly experimental, but it would be interesting. Checked the weight, not dramatic, but the arm to the prop longer and those two extra jugs also further out.

I know of a experimental super cub with a IO-360 6 cyl Continental. The airframe appears to be a little larger than a stock cub and the workmanship is fantastic. I understand it really performs. The Continental is heavier than the Franklin. There even some out there with 540 Lycs.

Landing performance suffers the heavier they are.

Check out

www.pepsiteam.com

or

http://www2.tsixroads.com/Corinth_MLSANDY/jk013.html

to see Pepsi's Supercub Skywriter and Nighttime Pyrotechnic Performer. It has an Lycoming IO-540 and a bunch of other mods and additions to customize it for optimum skywriting and airshow performance. Its definitely a fun airplane to fly. I don't have any solid numbers, but when I'm in it lightly loaded (no smoke and 20 gallons 100LL) it will roll as little as 4 seconds before liftoff. (this is all from memory, haven't flown it in about two months.)

Here is a beautiful Experiment licenced "scratch build cub" powered by a Continental I0-360. This is owned by a super craftsman from St. Mary's Idaho.

shown at the Evergreen 43 annual EAA flyin in July
Tim

Here is another Cub on Steroids! Owned by a retired dentist in Oregon! This one is powered by a lycoming I0-540, 260hp that was engineered by Byron Root (Sherpa). this thing is amazing as for packing a load! Check out these barndoor flaps. It has a Pawnee tail, a Cessna 185 tail spring and wheel and ailerons that look like they came off a gruman goose! (It's for sale??) Murph I think this is what you need down there on the Farm??

Tim

Don't forget the law of diminishing returns.

The WWII a/c designers figured out that they could build bigger radial engines for bombers and make more horsepower, but the things weighed enough to cancel out the power increase when it came time to see what the a/c performance was like.

It's nice to think about a highly overpowered Cub, but the landing performance should suffer from the weight increase, unless you don't carry any load.

I haven't experienced any of these 6 cylinder Cubs, so... Any one have performance numbers?

That red and white Cub by Root looks cool, though.

Dave Calkins. Light and Heavy Cub owner/pilot.

David, YOu got it right about weight verses horsepower! The Steroid cub that I posted has some great design ideas but weighs 15001bs! Yikes that is heavy like a 185! there are some significant tradeoffs!

The tailwheel stinger is a great Idea! I would love to see a light version for a cub!

Heck a guy needs one for each day, someone to keep them in tip top shape so we can just fly, have fun, if they break we just grab another and do it all over again!

How was hunting season this year?

Tim

Franklin 220 in a Super Cub

PA-12 driver, If you like the stinger tailspring Aviation Products,Ojai,CA makes one that would work on a cub. They will make about any size stinger you want. They have a double fork tail wheel that looks good but I dont know what kind of real abuse it would take. I recently bought one and so far Im just using it for a wall ornament.

I am all ears and eyes? can you take a picture and post it or send it to my e-mail address?
Send a PM if you prefer.

Thanks,

Tim

No kidding on the need for more than one arrow in your quiver.

Crash has that now, with his 14 and 18.

I'll have it when my present 11 project is finished, I've got a 14 flying now on floats. The 11 is for my wife. Well, she's working on her private, and I'm proud to be able to put her in a sweetheart of an a/c when she's finished.

I've been thinking of a fresh project after this consisting of a new Airframes, Inc. fuse and new Dakota Cub wings. At this point, just started dreaming of it. Yes, light weight will be very near the top of the list.

Another point on the large/heavy engined Cubs. I'm sure these things are using some method of getting the CG back in place that might include lead on the tail, or battery placement way back where? The problem I see here is that with all that weight up front, and all that weight back on the tail, the weight distribution has now been spread out further from the CG.
A see-saw that has heavies on each end will change "pitch" more slowly and tend to have more inertia in the direction of movement once in motion, than a see-saw with empty seats on each end.

I recall reading of a freshly refurbed and overpowered Pitts, an S1, I think, that was lost within a short time of the rebuild. The owner had reengined with 6 cylinders, and added, or distributed equipment toward the tail to get the empty CG correct. No Problem, right? Well, oops, the thing didn't seem to fly like he remembered it, but it DID fly, so he did a bit of his normal aero. routine. He entered a spin, but was unable to recover, apparently due to the wieght distribution causing the thing to stay spun, and even flatten in the spin. He threw his reserve chute and was unharmed.

I'm not so sure about the tubular tailwheel spring. I've seen broken 185 tailwheel springs, and I'm sure a light version for the cub could go, too.

The multiple leaf we are using does provide some measure of redundancy, and it's already figured out.

I'm sure the superlight-STOL contest guys could justify nothing more than a tailskid, even.

I've been so busy with Cessna and helicopter inspections late this season, along with a 185 wing tip/leading edge repair, and another 185 tailcone repair, that I haven't done more than get almost enough fish in the freezer. I hope to get out to Montague Island for some blacktail, but the longer I wait, the worse the storms get, and the longer they stay over the gulf. It's almost exclusively a beach operation, with some locations allowing one to get the a/c above the high tide line. Fish and GAme also deposit all the "problem" bears on this island, and they've been trained to arrive shortly after a rifle report. But, it's close enough to do the suicide run over a nice weekend.

No, it ain't perfect in Alaska. But if you want to visit, AND THEN LEAVE, I welcome one and all. Well, maybe one or two.

Dave Calkins.

Thanks David, sounds like you are looking in the similar direction as I am on "next project"?

I still have roots planted in Alaska having moved there before most of those that make it "their" home even new what "Chichako" ment? I have flown, hunted, got lost, wet and had fun all on the same trip to montague Island, Just a thougtht there used to be a lot of deer on Green Island that were overlooked except by the "locals"?? The ferry boat still makes a good wake to follow back to seward if the weather goes to H@@#$l as it always does about this time of year. I can remember actually landing on the uper beach on skiis one winter and then hunting for deer below us that would not leave the beach, mussels etc. What a hoot that was!! I used to have a 53 180, and a cub, then a TCraft/180, then a 185/PA18 and now I just have the PA12, wishing I still had both! Like you said keeps us dreaming, working and believing for more!
As for the WB/CG you are right on as to the empty weight problem with these "heavy haulers" they only make sense when they are "earning their keep" IE: the Beaver, 206, 185/ Otter and possibly the "Sherpa".

for sport you can't beat the Supercub/PA12/PA14 and multiple trips if neccesay (part of the fun right?)

Tim

PS: get out of the shop as much as you can!
PSS; where is your shop? how long have you been in the State? we should have crossed paths?

Send a PM if you want to?

"I've seen broken 185 tailwheel springs"

I've replaced stingers on two 180s in the past... They were both caused by internal rust... I plugged the end on my 185 stinger and kept some oil in it... Probably overkill, but it hasn't broken...

David

Cub Junkie, what's that tubular tailspring weigh?

Everyone calls them stingers, but in the Cessna pubs., the stinger is the tailcone fairing with the nav light in the end of it.

...thought we all should be educated.

STC'd?

How many flying?

If it's light, it may be worth a try.

Dave Calkins.

Franklin 220 in a Super Cub

No Dave I dont believe it is STC'D I just threw the idea out there as PA-12 driver mentioned somewhere he would be going exp. catagory on his next cub. Im sure to get it approved it would have to pass all the Fed's drop tests and other requirements. Im building an exp. cub clone so I can avoid the usual type certified rules. I wont ever be using my cub for commercial flying so I choose to go this route. As far as weight the spring feels lighter than the standard J-3 type spring when I pick it up but I have not weighed one. I did use a slightly smaller version on a Pitts S-1 with good results but of course this is the kind of aircraft that will never see conditions that are routine in AK. The tailspring I have now is 1" dia. at the forward mounting point tapering to 3/4" at the tailwheel and is 20 " long. It is the one being used on the big Pitts that uses the Russian radial. I just feel like the standard old leaf spring is model T technology although they do work. CJ

PA12driver said:

Thanks David, sounds like you are looking in the similar direction as I am on "next project"?

I still have roots planted in Alaska having moved there before most of those that make it "their" home even new what "Chichako" ment?

Click to expand...

The correct spelling is cheechako. Did you also attend school in the bush?