Flight safety, we discuss it, accept it and in many ways hope we choose it in our day-to-day functioning in the airplane world. For the Super Cub fanatic, Dakota Cub’s Extended Slotted Wing gives you the opportunity to enhance your margin of safety as well as maximizing the climb performance of your airplane.

Would you dare consider flying your Cub at a high angle of attack whilst the airspeed indicator shows 20, then roll it into a 60-degree bank and attempt to climb out at less than full power? That is the signature exhibition that sells the Dakota Cub Extended Slotted Wing. The second most talked about quality of this wing is the ability to have full flight control authority at high angles of attack. No more soft controls, plopping it down, or wing drop on stall.

Mark Erickson, the founder of Dakota Cub, began his journey in the 1990′s. He wanted a Cub rib. None were available from Piper at a reasonable cost, not to mention the Piper ribs are fairly fragile, so he made his own. He applied present-day technology to an old Piper wing that was originally developed for the YL-14 liaison version of the J5C Cub. The YL-14 wing was slotted. According to Erickson, there were only 14 of these aircraft built before the end of the second world war. They were designed to take-off in 100 feet and climb at a high angle of attack. Today, there are two still flying – one in Spain; the other in Nebraska.

The Dakota Cub Extended Slotted Wing has many differences in contrast to the original Cub wing and the L-14 wing for that matter. Erickson revised the original Piper US35B airfoil used for the L-14. He created a custom “T” shaped extrusion with the same dimensions that when used in building a truss-style rib, is lighter, easier to work with, and stronger than the original wing. Erickson was granted a STC for his new wing in 1993.

The new standard rib only adds seven lbs to the weight of each original Piper wing. The new wing has been structurally tested to in access of 2,200 lbs, however, the STC limits the gross weight to 1,750 lbs for the original wing or 2,000 lbs for those wings equipped with the Wipaire One Ton Cub STC. This artificial reduction will hopefully be changed in the future. In the intervening years, Erickson has designed ribs and many other parts that are FAA PMA-ed for all rag-wing Pipers. Erickson was granted the STC for the full-length leading edge slot in 1998. This slot helps preserve the boundary layer of airflow at slow speeds. In addition, Erickson designed a squared off wing and eliminated the tip bow providing the wing 6% additional wing area, enlarged the flaps which results in 44% more flap area, and moved the ailerons 23-inches to the end of the wing. He appropriately refers to it as the “Extended Wing.” The squared wing adds approximately eight pounds to the original Piper wing.

Adding a slot to the Extended Wing adds another nine pounds per wing, but the increased safety envelope from which to fly is well worth the trade-off. The flight characteristics of the squared-off and slotted wing, also referred to as the “Extended Slotted Wing”, is the main advantage and emphasis with regard to choice of wings to include in your Cub project. The Extended Slotted Wing is the highest performance wing offered by Dakota Cub. It has a 135-inch slot, a squared-off wing with 102-inch ailerons, and a 90.25-inch flap. In addition to the extended slotted wing, Dakota Cub also offers the standard Cub wing and a squared-off wing without the slot.

The Extended Slotted Wing is simply a safer wing. It enables a higher critical angle of attack, reduced stall speed, and practically eliminates the abrupt loss of lift in opposition to a straight wing. It delays the separation of the air flow from the wing surface, thus aileron authority is maintained and in many cases the only indication of a stall will be a higher-than-normal rate of decent. This allows the pilot to control the sink rate on a landing approach with power alone, which in turn allows a far more accurate touchdown without worrying about the wing stalling. The wing also has an improved roll rate due to the ailerons being extended to the end of the wing.

If you want to take full advantage of the Extended Slotted Wing on your Super Cub, then it is recommended to install a 3-inch gear extension. The gear extension will allow the slow speed capabilities of the wing to take full effect upon landing. Installing bigger tires will allow for this effect even more. Short gear coupled with small tires will result in tail wheel first landings and a take-off run that is longer than optimal because it’s more difficult to achieve that higher angle of attack.

The culmination of all this is a Cub that lands slower, provides optimal power/sink control on landing, has better climb performance and a much larger margin of safety.

A wide-body fuselage from Airframes, Inc features an extended fuselage, and when combined with the larger control surfaces and the slot, a pilot can fly at a 45-degree nose-up attitude, land at 25 knots, and still have a wing that hangs in the air.

Whether building a Super Cub or an experimental aircraft such as the Super Breezy, the Dakota Cub slotted wing would be a great asset to your aircraft for both safety and performance reasons.

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