Bearhawk Patrol & Piper PA18 Super Cub Comparison

 

The Piper PA18 Super Cub is probably the most appreciated and proven back country utility plane in the history of aviation. Since the 1950s, pilots’ lives have depended on the ruggedness and short field ability of the PA18. Perhaps no other airplane has a more devoted following because of the 60+ years of service in the back country. Today, there are many original Super Cubs still flying, and also many Cub “clones” with various design modifications attempting to improve on the 1949 original design, which itself could trace its development all the way back to the E-2 Cub of the 1930’s. The Super Cub wasn’t actually designed but evolved slowly out of the long line of Cub models that had existed before.

It has been suggested by some that if the PA18 were designed again today, it would look a lot like the Bearhawk Patrol.  Bearhawk Aircraft would like to outline some of the differences in the original Super Cub design and engineer Bob Barrows’ 2004 design work that ended up being the Bearhawk Patrol.  We know that the PA18 has a loyal following, but let us highlight some of the design and performance characteristics of the two planes.  It should be mentioned that a certified PA18 can be used for commercial purposes, and an experimental BH Patrol (or PA18 clone) will always be only a personal use airplane.  However, owning and operating an experimental category plane does have many advantages for the private pilot. Our hope is that pilots objectively looking for a two place tandem utility plane will find a new Bearhawk Patrol to be a desirable alternative.

 

DESIGN FEATURES

 

BH Patrol

Stock PA18

Cabin Space

32” across

26” across, some PA18 clones little more

Wing structure (1)

Completely flush riveted, all aluminum skins, single strut

Fabric covered wings

Wing airfoil (2)

An efficient, modern Riblett GA30-4135 airfoil developed by Bob Barrows with assistance from airfoil designer Harry Riblett

1940’s 35B airfoil

Baggage door

21” x 27” unobstructed baggage door

Many now have a small triangular-shaped door up high. The tube structure does not really allow a bigger baggage door.

Landing Gear (3) Suspension system

Oil dampened spring shocks

Rubber bungee cords

Tail surfaces (4)

Airfoil shaped ribs on the hor. stabs and vert. stab

Flat tail ribs

 

Very big, high visibility side windows going far aft, a huge skylight over the cockpit

Also excellent visibility

FLIGHT CHARACTERISTICS & SPECS

Cruise (180 HP, 75% power)

130-143 mph, fixed pitch props

150-162 mph C/S props

90-95 mph

110-120 (fastest new Cub-based designs)

Stall speed (5)

Mid 30’s MPH

Mid 30’s MPH (stock wing)

Empty weights

900 – 1200 lbs

960 – 1300 lbs

Gross weight (6)

2000 lbs (utility category strength)

1500-1750 lbs, (standard category strength) 2,000 lb gross mod available

 

(1) An all aluminum skin, flush riveted wing is the strongest for its weight, has the most efficient drag characteristics because of the consistent wing shape (with no scalloping between ribs) and lack of rivet heads in the breeze. Throttled back to Super Cub cruising speeds, a Bearhawk Patrol will have at least a 30% fuel savings when compared to a PA18.

(2) Developed by Bob Barrows with airfoil designer Harry Riblett, this airfoil is a turbulent flow airfoil designed for back country flying and great stall characteristics. Very little pitching moment requiring minimal trim changes. At low airspeeds, will not produce the “moose turn stall”. This airfoil and wing structure are the main reasons for higher cruise speeds. Another major factor in the higher cruise is the single wing strut as opposed to the double struts required on fabric covered wings.

(3) Oil dampened spring shocks are very strong and do not have the tendency to bounce you back in the air. They “stick” very well upon touchdown.

(4) Airfoil shaped ribs on hor stabs and vert stab give more stability and control authority than flat ribs.

(5) The only way to really compare stall speeds is to do a wingtip to wingtip slow speed test. In 2012, Bob Barrows did this test flying next to a Northstar Cub with 190 sq ft of wing area. The stall break for both happened at the same speed/time. It was a tie with neither plane having a slower stall speed.

(6) Utility category strength translates into a 16% stronger structure when compared to standard category strength requirements. Added strength = additional safety.