Piper Dakota: Muscle Bird PDF Print E-mail
Written by Bill Cox   

The premise seemed a sure winner. Why not, Piper reasoned, create a low-wing competitor for the high-wing airplane many people considered the best general aviation single in the world – Cessna's ubiquitous 182 Skylane?

The high-wing/low-wing controversy had been around for years. High-wing fans argued that the top-wing configuration allowed a relatively unrestricted view to the critical lower quadrant, had the peripheral benefit of providing shelter during bad weather, and that there were, after all, no low-wing birds. Low-wing backers felt the low-wing position was safer in the pattern, as it didn’t block the view of the runway during turns to base and final; fueling was easier; and, after all, there were no high-wing jet fighters. (Okay, there was one, the Navy’s F8 Crusader.)

Back in 1964, when the Cherokee 235 was introduced, Piper was convinced the concept couldn't lose.

They were wrong. Despite its considerable talents, the Cherokee 235 was only a marginal success. Performance certainly wasn't the problem. Most of the numbers were the same as or better than those for the Skylane – a sea-level standard 1,000-fpm-or-better climb and an easy 140-knot cruise – and useful load was actually 200 pounds more than that of the Skylane.

For reasons that escaped both salespeople and marketing experts, however, the Cherokee 235 never captured the imagination (or the sales) of the flying public as did the Skylane. Perhaps it was the low wing that seemed so counter to the Skylane’s semi-STOL image, or perhaps the 182 – with an eight-year head start and 5,000 examples already sold – was simply too well–entrenched in the marketplace.

Whatever the cause, the Cherokee 235 never posed a serious threat to Cessna’s mid-performance single. By the third year of production, Cherokee 235 sales had dwindled to a mere 120 airplanes annually – a figure that would have today’s Piper executives dancing in the streets. (In contrast, Cessna sold nearly 1,000 Skylanes during the same year.)

In 1973, Piper tried to increase sales by changing the model name to Charger; then, it changed it again to Pathfinder in 1974. But nothing, it seemed, could push Cherokee 235 sales much above 150 units per year.

Piper subsequently upgraded the Cherokee 235 with the Warrior wing and renamed the airplane the PA-28-236 Dakota. The Warrior wing was a relatively new, multiple-section, semi-tapered airfoil that was to become standard on all Cherokees. The primary effect of the revised airfoil was to enhance roll rate and improve low-speed handling. The semi-tapered airfoil started about halfway out on the leading edge and tapered toward the tip from both leading and trailing edges. Perhaps most of all, it looked sexy.

Power remained pretty much the same as it had always been. The Dakota sported a severely underworked Lycoming O–540 powerplant, de-rated from its normal 300 hp to 235 hp at only 2,400 rpm, all facilitated by a relatively low 8.5 to 1 compression ratio. The result was a recommended 2,000-hour TBO.

A more-than-peripheral benefit of the low redline was reduced propeller tip speed. Prop noise is one of the primary contributors to aircraft flyover noise (better known as effective perceived noise level – EPNL). Fast tip speeds, especially those above Mach .80, are aerodynamically inefficient and produce noise levels that don't make friends around airports. With an 80-inch prop out front, the Dakota’s tips were turning only about Mach .75. (The 2,400-rpm redline was also the max cruise setting, incidentally, so you could virtually ignore the prop control except during run-up.)

img_8936Overall flyover noise level was measured at only 73 dB, a low score among medium-powered general aviation singles and in compliance with FAR Part 36 noise standards.

The cabin remained basically the same throughout the airplane’s production run – 44 inches across at the elbows and 47 inches tall. This ensured the Dakota a minor comfort advantage over the Skylane, in case anyone was interested.

Apparently, not many pilots were. The Skylane continued to outsell the Dakota, and perhaps the best of the Piper four-seaters lasted only until 1994 before being quietly phased out of production.

For many of us, it was a sad end to a good airplane. The Dakota had much to recommend it. Though it was the heaviest of the Cherokees, it had the strongest climb performance of any PA-28. It also, more than incidentally, would out-climb the Skylane handily.

Provided you were willing to fly in the bottom 8,000 feet of sky, you very well might see the 144-knot cruise speed listed in the specs, though 140 knots was a more representative max. Climb to 11,000 feet or more, and cruise was more like 130 knots.

The Dakota didn't do anything in a superlative manner, but its unusual capacity to do everything well consistently outshined everything else in the class. It was an immensely flyable airplane, easy to operate, and comfortable to fly for long periods of time. If you were willing to aviate at 11,500 feet or above, you could see near 700-nm legs.

With 235 hp under the bonnet and spiffily spatted wheels permanently affixed beneath the wings, the Dakota scored an easy fuel flow of 13.5 gallons per hour and could endure for 4.5 hours, plus reserve. Lower power settings allowed the airplane to linger aloft for as long as six hours.

Those racy wheel pants were critical to max cruise, by the way. Toward the end of the airplane’s production life, Piper made major drag reductions on the wheel fairings that resulted in significantly better speed. Try flying with wheels naked to the wind, and you'd reduce your cruise performance by 7 knots.

A recent test flight in a fairly typical, late-model Dakota showed an empty weight of about 1,750 pounds, leaving 1,250 pounds for useful load to reach the max gross 3,000 pounds. Subtract 432 pounds (the 72 gallons) of fuel, and the Dakota was still left with 818 pounds of payload. Using the FAA’s standard 170-pound allowance per passenger, you could fill all the seats with people and still have 178 pounds of baggage allowance remaining. Because maximum baggage was 200 pounds, you needed to make virtually no concessions to weight considerations on the Dakota, unless you were carrying a quartet of sumo wrestlers. Similarly, the CG envelope was huge and would accommodate nearly any reasonable load distribution.

If you planned to spend four or five hours in any normally aspirated general aviation airplane, the Dakota would certainly have been an excellent choice, and current owners report that they’re especially happy with the airplane’s performance. (One owner, Steve Swensen, of Ogden, Utah, created perhaps the most amazing renovation of a Dakota you’ll ever see. Check PIPERS, August, 2011.)

The seats are friendly, and they cushion your body in all the right places. Panel layout is conventional, but functional, with everything in its logical location. Visibility from the left seat is good, though not excellent looking straight down past the wing leading edge fairing.

No matter what wonderful things some of us may have thought about the old-style manual flaps on the earlier Cherokees, Piper upgraded to electric activation on the heavier, higher-horsepower models for the last few years of production. Acknowledging that nearly everyone else in the industry had already transitioned to electric or hydraulic flaps for many years, Piper apparently figured it was time to get in step.

Electric flaps are certainly more modern, but they do subtract some of the fun many pilots used to have with the old Johnson-bar flap handle. No one will ever mistake a Dakota for a Maule M7 during takeoff, but I used to love to fly jump takeoffs in older Dakotas.

Perhaps interestingly (or perhaps not), the technique with manual flaps was essentially the same for the Maule or the Dakota. Push the throttle to the stop, see 45 knots on the airspeed indicator, pull in two notches of flaps, and simultaneously rotate hard. Predictably, the STOL Maule, with its big wing, would outperform the Piper easily, though the Dakota still did an excellent job of jumping off and climbing up. Only problem was, you had to pull the Dakota’s nose off the runway with gusto, or the quick flap application would pitch the nose down and drive the nose wheel hard into the ground. The book says a Dakota will break ground in about 800 feet, but I’d bet the airplane could do better with proper technique.img_9019

At the opposite end of the flight, landings are pure Cherokee, practically guaranteed to make any pilot look good. With a full 40 degrees of flaps extended, approaches work well at speeds as low as 70 knots for short-field efforts. Again, the magic number for touchdown and rollout is around 800 feet.

One of the Dakota’s greatest attractions is the same one that has helped endear Skylanes to two generations of pilots. Both airplanes are amazingly simple to operate, extremely safe, and fairly durable. That, after all, is what most general aviation airplanes are all about. Every design represents a series of compromises intended to yield a given result, and every designer must decide what he or she is willing to trade to achieve the desired ends. Certainly, speed is a primary concern of all designers and pilots. Climb, useful load, and range are other consistently important considerations.

In many respects, Piper’s multi-talented Dakota may be the best combination of ingredients among four-seat simple singles. It offers near-Piper Arrow speed without the cost and complexity of retractable gear, and it climbs as well as, or better than, any single-engine piston Piper currently in production, except the Malibu, Mirage, and Matrix. It provides a payload for four unmatched by any other airplane on the market.

Perhaps best of all, it's basically still a Cherokee – gentle, forgiving, and friendly. For many pilots, that says it all.