Training Aircraft Review:
The Piper Warrior III
By Mark R. Twombly
For the last three decades, the training fleet has been dominated by two aircraft: the Cessna 150/152 and the Piper PA-28 Cherokee, later called the Warrior. Tens of thousands of pilots spent their formative flight hours in the diminutive two-seat Cessna and the larger four-seat Cherokee. Although Cessna stopped making the 152 in 1985, thousands are still answering the school bell daily as flying classrooms and rental airplanes. The same is true of the PA-28, with one important difference: Piper is building a new trainer - the PA-28-161 Warrior III - again.
Introduced early in 1961, the low-wing PA-28 marked a fundamental change for Piper. It was the first model built at Piper's new Vero Beach, Fla., facility instead of its ancestral home of Lock Haven, Pa. The Cherokee was also the first Piper built by riveting aluminum skins over a lightweight aluminum fuselage structure. Piper used to weld steel tubes into truss-like fuselages and then cover them with fabric or aluminum.
For a good look at the PA-28's semi-monocoque construction, remove the panel on the rear bulkhead that separates the baggage compartment from the aft fuselage. The minimalist structure you see is lightweight yet strong because the aluminum skin is integral to the fuselage's strength and integrity. It's also less costly to build than the steel-tube structures of old.
The basic PA-28 design has been the template for numerous Piper two-, four, and six-place singles, and even a couple of twins. But the original 160-hp, fixed-gear PA-28 lives on in the new Warrior III.
From its inception, the PA-28 was meant to be an inexpensive airplane that offered benign (safe) flight characteristics and reasonable performance. The stabilator, sometimes described as a flying tail, is one of the Warrior's distinguishing features. The entire horizontal tail pivots as one to act as the elevator. While it gives pilots a lot of pitch control, the stabilator was primarily used because it was considered more economical to build than a conventional stabilizer/elevator.
This philosophy - lower manufacturing costs - influenced the wing design as well. PA-28 Cherokees have stubby, constant-chord wing planforms similar in shape to another product with roots in Pennsylvania - the Hershey chocolate bar. The inboard portion of the Warrior's wing retains that Hershey bar shape, but the leading and trailing edges of the outer panels taper. This gives the Warrior a longer wingspan than the Hershey bar wing and, thus, a higher aspect ratio (the proportion of the wingspan and the wing chord). In general, a higher aspect ratio contributes to better climb and cruise performance because of lower induced drag.
The tapered portion of the Warrior's wing also incorporates some washout. Stand at the wingtip and sight down the leading edge, and you'll notice that the leading edge twists slightly downward near the tip. This decrease in the angle of incidence means that even when the wing root area has stalled, the outer portion of the wing continues to generate lift and the ailerons remain effective. All of that means the airplane is more controllable in an aerodynamic stall.
If you've logged any time in an older Cherokee or Warrior, you'll transition quickly to the Warrior III. Externally, it is similar to all PA-28 variants - Cherokees, Warriors I and II, and the two-seat Cadet - that preceded it. The cantilever wing (no supporting wing struts) is fitted with hinged ailerons and four-position (0, 10, 25 and 40 degrees) hinged flaps. The spring-loaded, balanced flaps are extended by pulling on a metal bar between the front seats. Small nose-down pitch changes occur when extending the flaps to 10 and 25 degrees. The pitch change is more noticeable with full-flap deployment.
Pitch trim is controlled by an anti-servo tab affixed to the trailing edge of the stabilator. Pivot the stabilator by hand and watch the trim tab: It moves in the same direction as the trailing edge of the stabilator, only more so. In other words, as the trailing edge of the stabilator rises, the trim tab deflects upward, but with increased travel. This increases the elevator's "feel" by adding to the force the pilot must exert to deflect it up or down. It also enhances the airplane's longitudinal stability.
While the PA-28 airframe is essentially the same, the cockpit clearly says that the Warrior III is not yesterday's Cherokee. The new cabin treatment begins with a gray, professional-looking metal instrument panel devoid of distracting plastic ornamentation. Flight instruments are arranged in a standard "T" pattern in front of the pilot, and there is plenty of unused space to add equipment and avionics. The panel incorporates larger engine instruments than previous models and has several new features, such as an annunciator panel, a digital ammeter display of the load on the alternator, a combination oil temperature/oil pressure/fuel pressure gauge, electric engine primer, and internally lighted rocker switches.
The avionics package included in the standard price of the airplane is for visual flight rules (VFR) operations. It includes a single nav/comm with VOR indicator, altitude reporting (Mode-C) transponder, avionics master switch, four-place intercom, and a headset. The optional "Advanced Training Group" for instrument flight rules (IFR) training includes all of the VFR equipment, plus a second nav/comm and VOR indicator, glideslope receiver and indicator, audio panel, and standby electric vacuum pump - a significant safety feature for flight in instrument meteorological conditions. The IFR-certified avionics package is a $13,430 option.
To keep all of the electronics humming at full song, Piper has upgraded the Warrior III from a 12-volt to a 28-volt electrical system. An external power receptacle is also standard equipment. The control yokes are heftier and fill the hand, and the front seats, both of which adjust vertically as well as fore and aft, are upholstered with durable, attractive gray vinyl and gray nylon cloth inserts.
Piper's approach with the Warrior III is to sell a completely equipped airplane. Few options are available other than the IFR avionics package and a heated pitot tube and annunciator. Features usually sold as options that are included as standard equipment on the Warrior III include dual hydraulic brakes, wingtip strobe lights, exterior paint with two color stripes, and a two-year spinner-to-tail factory warranty.
The Warrior is certificated in both the Normal and Utility categories. Steep turns, lazy eights, and chandelles can be performed (intentional spins are not approved) when the airplane is operated at or below its Utility category maximum takeoff weight of 2,020 pounds. No baggage or rear-seat passengers are allowed for Utility category flight.
Subtracting the airplane's equipped empty weight of around 1,500 pounds (slightly more with the Advanced Training Group) from the Utility weight limit leaves just 520 pounds for fuel and crew. That's not a lot, so crew and fuel weight must be carefully calculated when planning a flight to include these maneuvers.
The Warrior III has good weight carrying ability in the Normal category, however. With a maximum Normal category takeoff weight of 2,440 pounds, you have 940 pounds of useful load. If you top off the two 24-gallon fuel tanks with 288 pounds of usable fuel, you can still add 652 pounds worth of people and bags. A partial fuel load of 17 gallons per tank can be determined accurately by filling to a tab on the bottom of each fuel filler neck.
The 4.7-inch center of gravity (CG) range at maximum gross weight (increasing to 10 inches at 1,950 pounds gross weight and lower) offers good loading flexibility. Work several weight and balance problems, and you'll find it is possible to exceed the aft CG limit with an extreme loading arrangement - two heavy rear-seat passengers and 200 pounds in the baggage bay, for example.
According to the charts, no combination of heavy front seaters and fuel would exceed the forward CG limit. It should be noted that the pilot's operating handbook (POH) does not specify front or rear seat weight limits, but the weight and balance loading graph only charts moments up to 420 pounds for front seat occupants and about 340 for the rear seats.
For pilots reared in high-wing trainers, starting the Warrior's four-cylinder Lycoming will be routine save for switching on the electric fuel pump. The switch should be turned off momentarily during the pre-takeoff ground check to ensure the mechanical engine-driven pump is working, then turned back on for takeoff and initial climb.
Takeoffs normally are done with flaps retracted. To reduce takeoff distances for short- and soft-field departures, Piper recommends that the flaps be set at 25 degrees and the nose lifted at a lower airspeed. Rudder trim - a standard feature controlled by a knob on the pedestal below the throttle quadrant - can be used to center the slip/skid ball during climbs and in long descents. Turning the rudder trim knob changes the tension on a spring connected to the rudder pedal torque tubes. In other words, the trim knob changes the relative positions of the rudder pedals instead of adjusting a tab on the rudder itself.
In flight, stability is the Warrior's strong suit. Wing dihedral contributes to good roll stability, and the stabilator can be trimmed for hands-off level flight, even in turns. Deploying the flaps causes a mild pitch change that is easily trimmed away. Ailerons and rudder are not interconnected, and when banking into a turn, the nose will yaw opposite the direction of the turn (adverse yaw) unless positive rudder control is exercised. Control cables are stainless steel for corrosion protection.
Cruise performance is what one should expect from a 160-hp four-seat trainer: about 2 miles a minute. On our flight out of Vero Beach in Piper's Warrior III demonstrator, N9249J, we leveled off at 3,500 feet and set the power at 75 percent. The airspeed settled on 105 knots indicated airspeed (KIAS), which worked out to be about 111 knots true airspeed (KTAS). Piper's specifications call for a 116-knot cruise TAS at 7,000 feet mean sea level (MSL) and 75 percent power.
Maneuvering and flap speeds are comfortably high - 111 knots at maximum gross weight and 103 knots, respectively. Because these speeds are in the neighborhood of indicated cruise airspeeds, drastic power reductions shouldn't be necessary in rough air or to deploy flaps.
Maneuvering speed (VA) decreases linearly to 88 knots at 1,531 pounds gross weight, so at a typical operating weight of about 2,125 pounds, VA would approximate flap speed: 103 knots. That makes it easy for Warrior pilots to remember the specific maneuvering speed. Another comfort factor is the 20-knot margin separating the 126-knot maximum structural cruising speed (VNO, top of the green arc) from typical indicated cruise speeds. It would be difficult to exceed VNO, even in a high-power descent.
The Warrior's inherent stability, low stall speeds, and good weight distribution stack the deck in favor of well-executed approaches and nose-up touch downs.
A mature design with a fresh approach on the inside, the Warrior III offers stable and predictable handling, good load carrying capability, and reasonable cruise performance. Those are the qualities responsible for the 35-years-and-counting production run of this most basic of the PA-28 family.
Piper PA-28-161 Warrior III
Single-engine, fixed landing gear, four-place, low cantilever wing.
Powered by 160-hp (@ 2,700 rpm) four-cylinder carbureted Textron Lycoming O-320-D3G engine and fixed-pitch two-blade 74-inch-diameter Sensenich prop. Base price for standard avionics-equipped version: $128,500. The Advanced Training Group avionics is a $13,430 option.
Length 23 ft 9.6 in
Height 7 ft 3.6 in
Wingspan 35 ft
Wing loading 14.4 lbs per sq ft
Power loading 15.3 lbs per hp
Maximum baggage weight 200 lb
Maximum ramp weight 2,447 lb
Maximum takeoff weight 2,440 lb (2,020 lb Utility)
Empty weight as tested 1523.2 lb
Useful load 923.8 lb
Payload w/full fuel 635.8 lb
Fuel capacity 48 gal useful
VNE 160 KIAS
VNO 126 KIAS
VFE 103 KIAS
VA 111 KIAS
VSO 44 KIAS
Takeoff distance, ground roll 1,120 ft
Takeoff distance over 50 ft obstacle 1,650 ft
VX 63 KIAS
VY 79 KIAS
Cruise speed 116 KTAS (7,000 ft, 75 percent power)
Range 520 nm (7,000 ft, 55 percent power, 45 min reserve)
Landing distance over 50 ft obstacle: 1,160 ft
Landing distance, ground roll 625 ft
Manufacturer's specifications based on sea level standard conditions unless otherwise indicated. For more information contact Piper Aircraft Corporation, 2926 Piper Drive, Vero Beach, FL 32960; telephone (407) 567-4361.
How Safe Is It?
Does the PA-28's safety record support its reputation as a docile airplane? For the most part, the answer is yes, according to a safety review published by the AOPA Air Safety Foundation (ASF).
The ASF studied National Transportation Safety Board (NTSB) reports on 1,164 accidents involving fixed-gear PA-28s that occurred from 1982 through 1988. (The study also looked at the safety record of retractable-gear PA-28 Arrows, but that is not discussed here.) Of those, 415 were described as serious, resulting in serious or fatal injuries, and 747 as minor. The ASF found that nearly 83 percent of PA-28 accidents were caused by pilot error. This is consistent with the ASF's analysis that pilot error accounts for about 80 percent of all general aviation accidents.
The ASF review showed that low-time pilots and those with little PA-28 experience are the most vulnerable to accidents. A little more than 37 percent of serious accidents involved pilots with 200 hours or less total time, and most of those were pilots with between 100 hours and 200 hours. The ASF speculates that new pilots become overconfident of their abilities and explore flight environments for which their training has not prepared them. More than half of serious accidents involved pilots with 200 hours or less time in PA-28s.
Pilot-error accidents in the PA-28 follow a lamentable and preventable pattern: visual flight rules (VFR) and instrument flight rules-rated (IFR) pilots flying VFR into instrument meteorological conditions (IMC); poor aircraft control during the critical phases of flight - takeoff and landing; and running out of gas. The study also showed that flying in IMC at night carries a significantly higher risk than in daylight.
The safety review did not uncover any design features that could be said to contribute to accidents. Aircraft-related accidents accounted for only 8.1 percent of all PA-28 accidents in the study period. Of those, powerplant or propeller problems rank highest, but that is consistent with other type aircraft.The ASF found that the PA-28 accident history compares to similar fixed-gear aircraft, such as the Cessna 172.
The lesson that PA-28 pilots - or any pilot, for that matter - can learn from the ASF's safety review is to analyze your skills and fly within them. The ASF's PA-28 Safety Review includes selected accident briefs, and a ground and flight training outline that instructors and students can use to transition into the airplane. The curriculum focuses on those areas that have been shown to be high-risk factors.
The ASF's Piper Cherokee and Arrow Safety Review is available through Sporty's Pilot Shop catalog for $22.95 plus shipping and handling. Call (800) LIFTOFF.
Given the nearly 35-year legacy of the basic PA-28's design and history as a training aircraft, one would expect the Warrior III to exude features conducive to flight instruction. And that is pretty much the case. Among its attributes:
From the metal panel and new yokes to the inertial reel seat belt-shoulder harness latches to the upholstery, the Warrior III cockpit is functional and attractive. Of special note for training are the four-place intercom, left and right yoke push-to-talk buttons, and vertically adjustable front seats, all of which are standard equipment.
Instructors who delight in pulling circuit breakers and flipping electrical switches on students to test their coolness under fire will love the Warrior III. The rocker-type electrical switches and pull-out circuit breakers are positioned on the right side of the panel - in front of the instructor. The good news for students is that the annunciator panel will light up orange to alert the pilot to the disabled circuit or switch. Another feature in the student's favor - and to an instructor's disadvantage - is that the fuel selector is on the left kick panel, well out of the instructor's reach.
Foolproof and intuitive, the manual flaps provide the kind of feedback that isn't possible with electrically actuated flaps.
There's no way the door will pop open in flight unless you really work at forgetting to secure the top latch of the Warrior III's double door latches. Unfortunately, there is only one door to latch. A left-side door would be nice.
The generously sized baggage compartment can swallow up to 200 pounds of flight gear, extra oil, overnight bags, and whatever else students, instructors, and schools can think of to toss in there.
A 10-foot-wide main-gear tread makes for stable ground-handling and good crosswind directional control.
Birds beware: Each side of the upper cowling lifts up to expose the entire engine compartment for a thorough preflight inspection.
The electrical system is 28 volts strong, more than enough to power everything electrical.Even with the tanks topped off with 48 gallons usable fuel, some 635 pounds of payload is available for people and bags.
The Warrior lacks the handling challenges and lessons of a Tomahawk, but it's no-surprises manners makes it a simple, stable, and predictable airplane.
Piper Aircraft Corporation, one of general aviation's Big Three airframe manufacturers (Beech and Cessna are the others), is poised to emerge from nearly four years of operating under Chapter 11 bankruptcy protection. Forced into bankruptcy by years of declining sales and production as well as management missteps, Piper was thought to be finished.
A new management team has confounded critics by rebuilding the company, paying off much of the company's debt, and reintroducing the entire piston product line. Piper plans to build at least 151 aircraft in 1995, which may make it the world's leading producer of piston-powered airplanes.
Piper is preparing to emerge from bankruptcy under new ownership, and creditors may soon be given a chance to vote on one of two ownership proposals. Either way, it appears Piper may once again assume a leadership role among general aviation manufacturers.