New Backcountry Super Cub Revision-2 Improvements
Flap Actuator modifications:
Backcountry Super Cubs is currently developing a modification kit to lessen flap deployment forces.
The complete retro-fit kit and instructions will be available Spring, 2017.
This modification is specific to the Keller Flap Option.
Backcountry Super Cub Improvements over the PA-18
Backcountry’s focus on improvements to the original Piper PA-18 has helped evolve our aircraft as well as our company.
Some of these changes are popularly referred to as “Alaska mods.” All of these improvements are now standard on our Backcountry Super Cub Rev-2 and BOSS kits.
It is worth noting that structure of our Backcountry Super Cub is the foundation for all of our other kits. Hence, our SQ-2, Supercub Revision-2 and now our new 4 seat BOSS line of aircraft all inherit the durability and outstanding performance that began with our original improved PA-18.
- We use 100% Chrome Molly tubing in our aircraft kits compared to about 35% in the original PA-18.
- The left side door is an extremely popular feature for the builder that is going to have floats on most of the time. Not recommended for wheel applications ( added weight, air leaks, throttle has to be moved etc).
- 3/4 Tubing: We use 3/4 tubing all the way through to the firewall. The original fuselages used to taper from ¾ to 5/8 for production purposes (they used to make the fronts separately and just slide them in), but for our purposes we like the large diameter tubing.
- All kit fuselages are beefed up for the new high Hp engines.
- Overhead X Bracing: Overhead X bracing is one of the more well known improvements on the Super Cub. It gives more strength to the upper cage when there is a wing strike.
- Extended baggage with the reverse dogleg is also a very common improvement to the original Super Cub and is also incorporated on our planes. The extended baggage gives three times the storage room.
- Baggage doors were not that necessary on the original Super Cubs because of the small baggage. With the big baggage now available it is now necessary to be able to get your baggage in the back. These kits have the option of 5 baggage doors; two lower right; 2 lower left baggage doors and one upper right.
- The wide body fuselage has been one of the biggest hits as far as improvements go.
- Nut Plate Brackets: These are be installed on the bottom of the rear of the fuselage to allow for a larger access plate.
- Shoulder Harness Mounts are a popular add-on. Original cubs have to use a heavy bolt-on bracket as per STC.
- Tail Spring Mount square tubing always ended up caved in on original Super Cubs. The fix for this is to weld a bushing in the tube to keep it from compressing. Our fix was to use heavier tubing for the extra strength in this area.
- Lower Tail Brace Wire Attach is a little weak on the original Super Cubs and this is not a good place to be weak. We have a heavy duty fitting here that actually bolts on to the tail wheel fitting as well.
- Front Seat Belt Brackets originally were installed on the seat itself. We decided to mount them directly to the fuselage.
- Weld on Float Fittings are installed on all planes unless otherwise specified. We also install the tabs for the pulley brackets on the aft part of the fuselage for the water rudders.
- Float Bushings are welded directly to the upper front of the cabin area. An “I” bolt is placed in the bushing when wanting to lift the plane to install floats.
- We use 0.49 tubing on motor mounts instead of the original 0.35. The original motor mounts were basically the same as the J-3’s strength-wise, but now instead of 65 Hp the planes are 180 hp or more.
- On a lot of pulley brackets and tabs we have gone one gauge heavier on the thickness. On many of the planes we used to fix we noticed a lot of the fittings had been bent after years of hard flying and even harder landings. We have also added a lot of extra interior tabs as well. The Z shaped door frames have been added to help seal the doors.
- We also put handles for the tail on both sides of the plane. It’s easier to pull than push.
- Landing Gear: The first improvement is the main tube has been increased from 1 3/8 diameter to 1 1/2. The original gusset consisted of one piece of flat bar welded from the axle to the main tube. What we use in this area is a scab plate welded on the two tubes that about 6 inches long. The new flat bar is welded the whole length of this plate to help distribute the stress area. We use 1 1/2 axles as apposed to the original 1 1/4 axles. We also use a 5/8 tube in between the front and rear pickups.
Now on to the wings…
- All of our wing structure is cut using CNC. Hence, the wings are consistently square upon initial assembly.
- Turbine cubs of Wyoming LLC, Smith Cubs Aviation, Home Built aircraft, SUPER CUBS Long Leading Edge: a customer in Alaska recommended the long leading edge to us. We were to learn that this had been used for a number of years in the Alaskan region with good results.
- Bow Tip: How many times have you seen a J-3 or Super Cub with a pushed up or worse broken bow tip, and still flying around? On our round-tip wings, we use aluminum round tube instead of the original wood.
- Our extended wing (actually same length, but full ribs and no bow on the end) along with the long leading edge have been the major contributors to our customers’ excellent performance figures. Instead of tapering the wing and using the wing tip bow, we use full ribs to the end of the spar with excellent quality fiberglass tips. We have extended the ailerons 14 inches and the flaps an extra 12 inches. The extra length of flaps and ailerons required an extra hanger, increasing the number of aileron hinges from three to four and the flaps to three instead of the original two. The original flap was driven from the inboard hinge, but with the extra length of flaps, we drive the flap from the middle to eliminate any extra stress.
- The ribs we use are very different in many ways, but not in the shape. We have kept the famous profile of the original Super Cub, for the perimeter of the ribs we use an extruded cap strip. It has an offset T-shape that will allow you to either use pop rivets or rib stitch your fabric on the wings. This extrusion is also a lot stronger than the original ribs.
- We use hard aluminum rivets in the wing components wherever possible.
- Instead of using the standard wire bracing in the wings, like the original Super Cubs, we use drag and anti-drag compression tubes. It’s basically the same concept as the first bay (where the gas tank is and uses a 4130 tube) in both Pipers and ours. We continue to use this theory the full length of the wing.
How about some extra fuel?
- Extra fuel is always nice. Original Super Cubs had two eighteen gallon fuel tanks. Our standard tanks are twenty four gallons each giving you an extra twelve gallons.
- Outboard Tank: If you need extra fuel we also offer an extra ten-gallon outboard tank giving you a possible total of sixty-eight gallons. We only recommend the extra fuel line if it is necessary. I.e. Alaska, Northern Canada, etc…