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Pilot Flight Check
Piper DakotaThe Little Hauler
by EDWARD G. TRIPP / AOPA 308674
Photos by ROGER ROZELLE / AOPA 537321
The next-to-Iast Cherokee bit thedust last summer when the Cherokee235 was transfigured to the Dakota(PA-28-236). Piper may not have beenthinking of the load-hauling Englishversion of aviation's iron horse, theDouglas DC-3/C-47, when they conjured-up the name-but the new Dakota can do its share.
Piper's marketing program is to sellthe airplane as a businessman/pilothauler. Recent advertisements pOi'itionit as competition for Cessna's 230-hpSkylane.
As with all PA-28 derivatives, theDakota bears the familiar outline of its
predecessor; however, aside from thefuselage and tail feathers, there aremany changes and detail improvementsinside and out. The most apparentchange has been made to the wing:it's the longer span, semi-tapered,laminar-flow wing introduced earlieron the Warrior, Archer, Arrow andtwin-engine Seminole. Wing section isNACA 652-415.
The main spar carries through thecabin via a box structure. There areauxiliary spars front and rear; thelatter carries the loads of the aileronsand flaps. The ailerons are longer spanand provide better roll response. Each
wing contains a single, integral fueltank in the leading edge with a capacity of 38.5 gallons of 100/130 octanefuel. Usable fuel is 36 gallons per side,or 72 total.
Pilots familiar with the Cherokee 235will spot additional changes, many ofwhich are the result of closer attentionto detail, appearance and aerodynamicefficiency by the manufacturer. TheDakota's cowl is taut-looking. A prominent feature is a much larger spinner;another is the ram air intake, whichimproves engine breathing. The threepipe exhaust juts through the bottomof the cowl and has a fa ired lip ahead
JANUARY 1979 I THE AOPA PILOT 35
of it to improve flow. Cowl flaps arenot used.
Nestled within the close-fitting cowlis a 6-cylinder Lycoming 0-540-J3A5Dcarbureted engine with a power ratingof 235 hp at 2,400 rpm. It's mated toa wide-blade Hartzell controllablepitch propeller. The engine occupiesthe same space as the four-cylinderLycomings used in the 160-hp WarriorII and 180-hp Archer II. It is locatedback closer to the firewall to accommodate the two extra cylinders and other
PIPERDAKOTA
accessories of the larger engine.Another item aimed at reducing
drag is a set of large wheel pants combined with faired struts, which, thecompany claims, improves cruise speedby eight knots and range by six percent. The aerodynamic improvementrequires additional effort to check strutand tire inflation and tire wear, sinceonly the lower third of the tire isvisible. The air valve is accessiblethrough a small door on each fairing.
Overall, the appearance of the Dakota is pleasing: deep-throated yetsleek. The paint design works very wellwith the basic lines of the aircraft.
Access to the cabin is standard foraircraft of this type, through a singledoor on the right side of the fuselageover the wing, with a step below the
trailing edge of the flap. The right flaphas a lock in the up position to handlepeople weight, and doubles as a step.A baggage door on the right aft fuselage gives good access to the 24-cubicfoot, 200-pound-capacity luggage baybehind the rear seats.
The latches on the cabin door arepositive in operation and provide agood seal; wind noise around the sealis minimal.
Our evaluation aircraft, N22336, isa Piper factory demonstrator fittedwith all the deluxe options, includingbright royal blue velour upholstery.Cockpit layout is well planned andconsistent with what is approachingindustry-wide commonality. The basicflight instruments are grouped in a'T" directly in fron t of the pilot with
Cockpit access isthrough a single butgenerous, well-sealed
door. There is a large.flip-up door to thebaggage compartment.Head on, the moreefficient spinner andcowl. and the ram airintake show attentionto aerodynamicefficiency. The cowl;s easily removable.Underneath. the 6
cylinder, 235-hpLycoming fits thesame space as the4-cylinder cousinsthat power the Archerand Warrior models.
There's lots of spaceon the well-organizedpanel. N22336 has anoptional fireextinguisher mountedunder the panel abovethe right seat.
36 THE AOPA PILOT I JANUARY 1979
engine instruments below and avionicsmounted in the center of the panelabove the primary electric switches.
There is an annunciator panel abovethe flight instruments containingwarning lights for vacuum, alternatorand oil pressure. Environmental controls and circuit breakers are mountedon the right panel. An engine powerquadrant is centrally mounted belowthe panel with parking brake, ruddertrim and microphone below. The latterwas the only bothersome feature wefound in the cockpit. It was too easyto bump the mike out of its mountwhen using the brake or setting ruddertrim, spilling it somewhere on thedeck. This required a lot of gropingand head ducking at awkward times.
The fuel selector system is mounted
on the left sidewall by the pilot's kneeand is simple in operation (off, left orright). However, we would prefer apositive detent for each position, particularly when flying at night.
Elevator trim and the manual flapselector are located between the frontseats. We like the manual flaps; theyare positive, as quick as one wantsand should require less maintenance.
We also like the sun visors, whichare transparent, tinted plastic. Thevisor on the pilot's side incorporatesthe recommended power setting chartfor ready reference. Abbreviated checklists are printed on the instrumentpanel to the left of the control column.
Cabin space is good for four adults,and comfortable to both eye and body.All four seats have movable backrests,
with three positions to accommodatevarying sizes and to provide somevariation during long flights. The frontseats in 22336 have vertical adjustment, an available option. Some pilots-or their passengers-may find thatthe oversized headrest, which arestandard with the deluxe interior, interfere with visibility from the back seatsand create a feeling of isolation. Piperoffers a low-profile headrest in exchange, which we haven't seen.
Leg room is adequate, although oversix-foot pilots might take up moreback seat leg room than we wouldlike. Armrests are molded into thecabin sides in the front cockpit andinertia-reel shoulder harnesses arestandard. Shoulder straps are an available option for the rear seats. We think
Piper PA-28-236 DakotaBasic Price $36,750
Price as tested: $61,819
SpecificationsLycoming 0-540-J3A5D
235 hp @ 2,400 rpmPropeller Hartzell Constant-SpeedWing Span 35 ftLength 24 ftHeight 7 ft 4 inWing area 170 sq ftWing loading 17.6Ib/sq ftPower loading 12.8Ib/hpPassengers and crew 4CaWnkn~h 8ft1inCabin width 3 ft 5.5 inCabin height 4 ft 1.inEmpty weight 1,633.5IbEquipped empty weight 1,795.9IbUseful load (basic aircraft) 1,366.5IbUseful load (as tested) 1,204.1IbPayload with full fuel (basic
aircraft) 934.51bPayload with full fuel (as
tested)Gross weigh tFuel capacity (standard)
PerformanceTakeoff distance (ground roll) 810 ftTakeoff over 50 ft 1,300 ftRate of climb (gross weight) 965 fpmMaximum level speed 148 ktNormal cruise speed
(75% power, 9,000 ft)(65% power, 12,000 ft)(55% power, 15,000 ft)
Economy cruise speed(55% power, 15,000 ft)
Range (45-min reserve)75% cruise65 % cruise55% cruise
Service ceilingAbsolute ceilingStall speed (clean)Stall speed (gear and flaps
down )Landing distance (ground roll)
1,040 ft1,740 ft
Engine
Oil capacityBaggage capacity
Landing over 50 ft
772.11b3,000 lb
77 gal(72 usable)
12 qt200lb (24 cu ft)
144 kt138 kt131 kt
125 kt
696 nm769 nm800 nm
17,900 ft19,000 ft
63 kt
56 kt
JANUARY 1979 I THE AOPA PILOT 37
The Dakota shares the longer span, semitapered wing with the Archer, Arrow, Seminole and Warrior. The longerailerons provide more effective roll control than the original wing used on the Cherokee line.
they should be standard. The rearseats can be removed to provide alarge area for bulky cargo,
Operations
Preflight, start and runup proceduresare simple and straightforward. Thereare no tricks to make transition difficult. The fuel system has a singledrain under each wing and there is agascolator drain on the left side of thecowl. During cold starts in temperatures ranging from 75° down to 20° F,it wasn't necessary to use the primer.Both cold and hot starts were accomplished without fuss, following thetechnique outlined in the operatingmanual.
The only fault we encountered inground handling was caused by thetow bar. It's too short. It fits neatlyacross the rear bulkhead in the baggage bay and has a positive lockmechanism to keep it in place. But itslength puts the pilot's nose rightagainst the spinner. If he slips, hegets a solid wack or a spear job. Thelarge angle also makes it easy for thenose gear attach points to slip, whichprobably will eventually take its tollon the nose gear fairing and the pilot's
38 THE AOPA PI LOT I JANUARY 1979
equilibrium. It may not sound likemuch, but trying to move the aircrafton a slippery surface or an incline ismore difficult and potentially hazardous than it should be, particularly foran airplane which is otherwise so easyto maneuver during hand towing.
Ground handling under power isgood. The Dakota is light on its feetand rudder pressure required for steering is minimal. Turning radius is ahandy 30 feet (with braking). Visibility on the ground is good, too. Someold Cherokee pilots may have difficulty until they get used to the longerwing span.
We may have been impressed by thelightness of the Dakota as a result ofhaving anticipated nose heaviness withthe larger engine. Light handling continues through takeoff and climb, however. A touch of aft trim and neutralpressure on the yoke gets the nosewheel unloaded and produces an unruffled takeoff. The airplane can behorsed into the air at 50-55 knots orballooned off the runway with 25 degrees of flaps. But, with a ground run(sea level, standard day) of 810 feetand 1,300 feet to clear a 50-foot barrier, all but the most poorly prepared
takeoff sites can result in a positive.short and unspectacular departure.
Best climb rate speed, 85 knots,gives a book climb of 965 fpm at grossand our often-below-gross takeoffs produced solid initial climb rates in excessof 1,100 fpm. The deck angle at thisspeed is high, however, and was usedfor the first 500 feet and for instrument departures only. Recommendeden route cruise climb is 100 knots, although we found 105 to 110 (depending on load) to be a good combinationof rate and visibility over the nose. Ifyou really want to impress yourfriends, the best angle speed of 73knots indicated gives a dramatic demonstration of what "hanging on theprop" is like.
In-flight visibility is good. The threeside windows provide a lateral coverage of about 270 degrees. Dipping awing from time to time in climb ordescent, particularly in high trafficareas, makes checking below for potential conflicts simple.
Controls are well balanced and light.Takeoff with the 235 horses and fatprop requires a healthy right boot.Rudder pressure is reduced with a fairamount of rudder trim which, if left
..•
Optional overhead ventilation systemprovides gO':Jd flow at reduced noise level.
The new, aerodynamically efficient wheelfairings improve cruise speeds by 8 knotsand range by 6% over a bare-wheeled Dakota..'Jut they extract a price in terms of moreCilre to check tire inflation and condition.
panel in the side windows is slightand not bothersome.
Long spells in the cabin are madeeasy to take by the combination ofgood seat design-good lumbar supportand adjustable back rest-and visibility. The best testimony for overallcabin comfort is that a passenger whowent along for the long cross-countryspent 90% of the time sound asleep.
uncontrolled and high density, high-performance air carrier airports. We wereable to use the airplane at full grossand full cabin at a variety of CG loadings and fairly light (900 pounds under gross). The simplicity of systemsand operations and the basic good balance of the airplane made all flights,including day and night IFR and several missed approaches, a pleasure.
The evaluation airplane, N22336,has a basic empty weight of 1,796pounds compared to the stripped emptyweight of 1,633.5. Payload remainingafter loading 432 pounds of fuel formaximum-range operation is 772pounds, or four FAA-standard peopleand 92 pounds of baggage to reachthe maximum gross weight of 3,000pounds. Maximum landing weight isalso 3,000 pounds.
Since the engine was still in itsbreak-in period we limited selection ofpower settings to fairly high rpm andfrom 60% to 75% power dependingon altitude. Leaning technique wasconservative (100 degrees on the .richside of peak according to the exhaustgas temperature gauge). Flight planning at these settings could dependupon an easy 4.5-hour endurance withat least 45 minutes reserve fuel.
It is obvious from our experience inthe Dakota that it is a good, highdensity alti tude performer, despite thefact that the engine is normally aspirated. Optimum handbook altitude is9,000 feet; service ceiling is 17,900.Judging by the climb perfurmance upto 13,000 feet on warmer than standard days, cruise altitudes of 15,000 to16,000 feet should be reached with noproblem (just don't forget the oxygenbottle). The airplane is definitely happier at altitudes above 6,000 feet .
Performance out of high density altitude airports, such as Stapleton atDenver, is good; climb from such airports to continental-divide-hopping altitudes is positive and at a good 500fpm at high cruise-climb speed.
Above 7,000 feet at cruise, withpower settings down to 60% at 2,400rpm, TAS was consistently above 140knots, usually 145 knots or better foran average load that was 300 poundsunder gross.
Cabin temperatures are comfortablein sub-zero centigrade environment,even for those who like a sauna-likeatmosphere. Heat distribution throughout the cabin is good. But watch theheating ducts that run along the spineof the cabin floor; they get very hotand can melt plastic. Our airplanefeatures the optional overhead airducts and blower fan, which we feelis more than adequate for most conditions and makes the air conditioningsystem a necessity only in the hottestclimates (and the former lists for $675vs. $2,305 for air conditioning).
Ligh ting and cockpit arrangemen tis good for night flying. It is easy toremember where things are located,and the lights make searching unnecessary for anything save for the unlighted (in 22336, at least) electricalswitch panel. Light reflection from the
on in level flight, makes the airplanetransit somewhat sideways.' Ruddertrim is positive but sensitive. The stabilator tail is positive and the longspan ailerons provide good roll controlat low speeds and in turbulence.
The overall responsiveness of theairplane is good. It takes little time tofeel confident and comp2tent in theDakota. Speed control is easy, and reversing vertical direction as in a missedapproach or go-around can be accomplished at will, even with full flaps.Lateral stability is the only area wefound to presen t potential problemsfor the unwary. Minor upset to eitherleft or right, if left untended, resultedin a spiral dive: the airplane did notappear to be self-righting. This isn't avicious characteristic, since entry isslow and gentle. But, if a pilot weredistracted or was unable to fly instruments, he might wake up to the condition after it was well-established andeither become disoriented, worseningthe spiral dive, or panic and overstressthe airplane.
It should be noted that Piper's salesliterature states that all but the mostbasic, VFR-equipped aircraft are fittedwith a wing-leveler or autopilot.
Slow flying the Dakota is a goodconfidence-building exercise. As withmost aircraft of its category, sta]]s takeconscious effort to perform clean ordirty, power on or off. Departure stallscall for a very high angle of attackand make one believe it takes a complete clod, who shouldn't be flying inthe first place, or a state of full-blown,out-of-control panic, to get into troubleclose to the ground.
Approach and landing are as effortless and simple as other maneuvers. Itis possible to fit in with high- or lowspeed traffic with ease (although a 130knot approach does mean more timesailing down the runway in groundeffect). A comfortable approach speedfor most conditions is 85 knots, reducing to 75 over the fence. Maximumflap speed is 102 knots, although wefound that even selecting the firstnotch at this speed produces a definitepitch-up; 90-95 for the first notchseems better, especially since a combination of pitch and gentle throttlereduction gives good, quick airspeedreduction.
There is plenty of pitch power fromthe stabilator. Full-stall landings areeasy to make consistently. Brakes areeffective too, unless one plunks theairplane down at too high a speed.
Our time with the Dakota includedsmall degree of wallowing, but theDakota handles it well. It is fairlyshort-coupled, and we anticipated agreat deal more pitch instability thanwe experienced. The only time pitchneeds much attention is in turbulenceduring hands-off flight. Once upset, itrequires attention to trim to return tohands-off .
Flight in turbulent air produces aa long-2,000-mile-cross-country, opperation out of sea-level and high density-altimde airports and both small,
JANUARY 1979 I THE AOPA PILOT 39
.\
PIP'ERDAKOTA
The Bottom Line
Our factory demonstrator is equippedto the maximum, as one might expect.The only piece of available avionicsgear missing is DME. The all-Kingpanel featured two KX170B nav /corns, audio panel, transponder, encoding altimeter, and ADF. An Edo-AirePiper AutoControl HIB two-axis autopilot with couplers and automatic trimis also part of the package. The electronics package makes up $14,555 ofthe total list price of $61,819.
Piper is concentrating on installation of factory installed avionics packages and offers basic one nav/comwith transponder packages at $4,255to complete IFR, shoot-the-works installations ranging above $30,000.
It isn't easy to compare base or evenequipped prices from one manufacturer to another because equipmentand pricing policies vary greatly. TheDakota has a basic equipped price of$36,750; N22336 carries an additional$25,069 worth of options. The basicprice does not include an ELT ($370with remote switching), which is required by law in the United States.
Our idea of a basic Dakota withoutavionics but specified for maximumutilization and anticipation of IFR operation would cost $42,680. This includes such basics as lighting andgyro instruments, pitot heat (the PA-28
40 THE AOPA PILOT I JANUARY 1979
series, with the pitot/static systemmounted under the wing, is very proneto insect or water clogging); it alsoincludes some nice touches, whichothers might not consider necessaryfor continuous use, such as supersoundproofing, overhead vent and fansystem and rear-seat shoulder harness.
Were we to purchase the aircraftfor our own use, there are a few options we would add-zinc chromateprimer, stainless steel control cablesand tinted windows-bringing theprice to $44,260.
We are sure the pricing policy ismade considering such applications asforeign markets and a variety of potential uses here in the Northern Hemisphere. However, since we are concerned primarily with owner-flown,personal and business use our idea ofbasic equipped price is necessarilyquite different from that of the manufacturers.
The Dakota offers a well-balancedvehicle for the business and recreational pilot who wants a combinationof simplicity, performan~e and versatility. Load, range and altitude flexibility plus cabin comfort and ease ofoperation make it a good little haulerwith a touch of class-a solid airplaneany pilot in the market for a singleshould consider. 0
Lots of attention to detailrefinements results in a
smooth. efficientpackage. The cowl
flares in front of the
three-pipe exhaust toreduce turbulent flow and
improve extraction.