Piper Aztec

Overview

The Piper PA-23-250 Aztec D is the fourth production iteration of Piper’s PA-23 twin, built between 1969 and 1972 at Lock Haven, Pennsylvania. It carries the same airframe geometry and 250-horsepower powerplant pairing as the C model that preceded it; the D’s distinguishing changes are operational, not structural. A redesigned instrument panel placed flight, engine, and navigation groups in standardized positions, and the control column was revised. Approximately 500 D-model airframes were produced before the longer, six-window E variant superseded it.

The Aztec sits in the load-hauling middle of the light-twin market. Empty weight is roughly 3,042 pounds against a 5,200-pound maximum takeoff weight, leaving a useful load near 2,158 pounds. With 144 usable gallons of fuel and six seats, an operator can fill the tanks, the cabin, and the 300-pound baggage compartment without exceeding gross. That property distinguishes the Aztec from most of its peers and earned it a long second life as a freighter, jump-plane, and bush twin in operations where useful load matters more than block speed.

Power comes from two Lycoming IO-540-C4B5 engines: six-cylinder, horizontally opposed, fuel-injected, 250 horsepower at 2,575 rpm, driving constant-speed Hartzell propellers. Time between overhauls is 2,000 hours. The combination is unhurried but durable. Pilots report 172-knot cruise at 75 percent power on roughly 27 gallons per hour combined, and 155 to 160 knots on 21 to 24 GPH at lean-of-peak settings. Single-engine performance is limited: 240 fpm initial climb at sea level and a 6,400-foot single-engine service ceiling mean engine failure at altitude or in summer density-altitude conditions demands careful weight planning.

The aircraft is most often described in the type literature as docile, stable, and forgiving. Those qualities suit it to instrument approaches, business travel, and owner-flown family use. It is not a fast airplane. It is a capable one, and the D variant in particular represents the last Aztec configuration before Piper’s 1972 stretch added cabin length and cosmetic changes that some owners feel diluted the type’s character.

Key Features for GA Buyers

• Useful load near 2,158 pounds. Six adults with bags and full fuel is achievable, which is unusual in this class.
• Fuel injection from Lycoming IO-540-C4B5s. Eliminates carburetor ice as a routine concern and supports leaning discipline. Well-supported through the Lycoming overhaul network with a 2,000-hour TBO.
• Six-place cabin with separate baggage compartment. A 300-pound rear baggage hold supplements the cabin and supports realistic family or business loads.
• Stable IFR platform. Type clubs consistently describe the airframe as well-mannered for instrument flying, holding altitude and trim with minimal pilot input.
• Strong short-field performance. 1,250 feet over a 50-foot obstacle on takeoff and landing, competitive with much smaller singles, and a reason the type persists in working operators’ fleets.
• Retractable tricycle gear, hydraulically actuated. Standard configuration; gear-extension speed limit (Vlo) of 132 KIAS gives flexibility on descent.
• Twin redundancy at a single-engine acquisition price. Aztec D market values run well below contemporary Beechcraft or Cessna twins of similar capability.

Trade-offs

• Block speed of 172 KTAS at 75 percent power. Acceptable for the era and the mission, but slower than a Baron or a Cessna 310 of the same period.
• Combined fuel burn near 27 GPH at 75 percent. Range is generous in absolute terms but cost-per-mile is high relative to a single-engine high-performance airplane covering the same trip.
• Single-engine ceiling of 6,400 feet. Engine-out climb at high density altitude is marginal; mission planning must respect this.
• Fuel-cell aging. Bladder tanks in older Aztecs are prone to leaks, and replacement is a documented ownership cost.
• Parts availability for D-specific components. Most maintenance items are common across the type, but some D-only interior, panel, and electrical parts are now sourced through salvage operations.
• Insurance complexity for low-multi pilots. Premiums and minimum-time requirements step up sharply versus a single. Quotes for low-time multi pilots routinely exceed those for high-time pilots by a factor of two or more.
• Limited utility above 12,000 feet. Normally aspirated; performance, true airspeed, and useful load all degrade in the high teens. The turbocharged Aztec D and Aztec E variants address this but are a separate type-cost conversation.

See Also

• Piper PA-23 Apache – direct predecessor on the same airframe with smaller engines. Compare
• Piper PA-34 Seneca – Piper’s natural successor light twin in the same six-place class. Compare
• Beech Baron 55 – contemporary Beechcraft six-place piston twin and direct competitor. Compare
• Cessna 310 – contemporary Cessna six-place piston twin and direct competitor. Compare
• Piper Navajo – Piper’s larger cabin-class step-up from the Aztec. Compare