PA-24-260B (1966 to 1968)
PA-24-260C (1969 to 1972)
PA-24-260TC (1970 to 1972)
With the 260 series, we start to diverge from the basic Comanche
idea in that these airplanes become more complex and the original Comanche
design is significantly altered. Even so, a total of 1,029 airplanes were
sold from the Comanche 260 line. These souped-up versions offered more
power (260 hp) and speed from the 250's O-540 - in the straight 260, thanks
to a 125-rpm increase in propeller redline (2,700 rpm, as opposed to the
250's 2,575 rpm); in the B and C models due to fuel injection and aerodynamic
improvements; and in the TC with the addition of dual manually controlled
Rajay turbochargers. Some 38 straight 260s came with carbureted engines.
The rest were fuel-injected. Recommended TBOs stayed at 2,000 hours for
all engine variants.
|The straight 260 was the lightest
of the pack, with an empty weight of approximately 1,700 pounds and a gross
weight of 2,900 pounds. Like its predecessors, it has four seats and a few
have carbureted engines. And like the rest of the Comanche singles, a 90-gallon-capacity
auxiliary fuel system was available as an option. Cruise speeds ranged
from 142 to 161 knots, fuel burns ran from 13 to 19 gph, and ranges with
IFR reserves go from 950 nm (90-gallon fuel system, 55 percent power, at
15,000 feet) to 550 nm (60-gallon fuel system, 75 percent power, at 8,000
feet). Full-fuel payloads ranged from 660 to 740 pounds. The 260 could
climb well, too: 1,500 fpm at gross weight under standard conditions. New,
they usually sold for approximately $30,740.
The 260B is the first "stretched" (by six inches over previous models, thanks to a longer prop spinner not a true fuselage stretch) Comanche single. They have a third side window and provision for six seats, although the fifth and sixth seats are suitable only for children and rob a lot of space from the baggage compartment. Fuel injection is standard in the B, which uses the Lycoming IO-540 of 260 hp. Empty weight is 1,728 pounds - most of which is explained by a soundproofing package that included thicker, double-paned windows. Gross weight was upped to 3,100 pounds, and useful loads rose 172 pounds - to 1,372 pounds - over that of the straight 260. Because of the extra weight, cruise speeds dropped three knots or so from the straight 260's values, but with the fuel injection came a reduction in fuel burns. These ran from 11 to 14 gph; ranges with IFR reserves go from 1,000 nm (90-gallon fuel system, 55-percent power, at 15,000 feet) to 550 nm (60-gallon fuel system, 75-percent power, at 8,000 feet). Maximum rate of climb is posted at 1,370 fpm under gross weight, standard conditions. New, 260Bs cost from $32,820 to $33,820.
|The 260C was the first really modern-looking Comanche single. It brought with it the advent of the 'Tiger Shark" cowling, another 100-pound hike in gross weight, cowl flaps, an aileron-rudder interconnect, multiengine-style power quadrant, and standard - T display of flight instruments. Its 1,427pound useful load is the highest of all the Comanches, including the twins, and is second only to the Comanche 400. Cruise speeds range from 150 to 161 knots, fuel flows from 12.5 to 14.1 gph, and ranges with IFR reserves from 870 nm (90-gallon fuel system, 55-percent power, at 15,000 feet) to 550 nm (60-gallon fuel system, 75-percent power, at 8,000 feet). Actually, the Tiger Shark cowling was not for looks alone. To prevent possible aft center of gravity problems due to the 260C's increased gross weight and its fifth and sixth seats, the propeller shaft was extended. This alteration moved the center of gravity slightly forward, which nipped the CG problem in the bud and made for a nice-looking cowl in the bargain. (Rumor has it that famed designer Ed Swearingen was responsible for the sleek-looking cowls, a variation of which were also adapted for use from the Twin Comanche's graceful cowlings.) When new, average-equipped 260Cs sold for between $36,550 and $45,990.|
The 260-TC, or Turbo C, is the hot rod of the 260 series. It has a turbo normalizing system with what Piper called a "second throttle" on the power quadrant. The procedure for using this manually controlled turbocharger was to first use throttle to bring manifold pressure up to a desired level. If conditions are such that insufficient manifold pressure is developed for the task at hand, then the drill is to begin closing the turbo's wastegate by moving the turbocharger lever forward. This raises manifold pressure to values as high as 29 inches MAP at altitudes up to 25,000 feet. In this way, the "second throttle" can make up for the adverse effects of high-density altitude. The turbo lever must be moved slowly to avoid sudden, inadvertent over-boosting. With full turbocharger and a power setting of 25 inches MAP, 2,400 rpm, and 15 gph, the TC could turn in a true airspeed of 198 knots at 25,000 feet. At 12,000 feet, the TC could still turn out 178 knots using 27 inches MAP, 2,400 rpm, and 15 to 17 gph. Range with the 90-gallon tanks could reach 1,000 nm with IFR reserves. Gross weight is 3,200 pounds, useful load is 1,306 pounds, and if you really had the need for speed, you could crack open the turbo at optimum altitude and achieve 210 knots. New, the TC sold for between $46,375 and $51,720.