The PA-44 Seminole was developed during the heyday of the GA industry in the mid to late 1970s but fell victim to the depressed market from the early 1980s plus the growing reliability and popularity of high performance big singles. As a result it has been built in only fairly modest numbers.
Interestingly the PA-44 is the only T-tail Piper currently in production, even though in the late 1970s most Piper aircraft had been modified to feature a T-tail.
The company was originally founded as the Taylor Brothers Aircraft Manufacturing Company in September 1927 by Clarence Gilbert Taylor and Gordon A. Taylor in Rochester, New York. The company was renamed Taylor Brothers Aircraft Corporation in April 1928, shortly before Gordon Taylor died in an aircraft accident on April 24, 1928. The company was enticed to move to Bradford, Pennsylvania, with the promise of larger facility and investment capital from local businessmen, including an initial investment of $400 from local oil industry engineer William T. Piper. The move was completed in September 1929.
Powerplants
PA-44-180 - Two 135kW (180hp) Lycoming O-360-E1AD flat four piston engines driving two or optionally three blade constant speed Hartzell propellers.
PA-44-180T - Two 135kW (180hp) Lycoming TO-360-E1A6D turbocharged flat fours driving two blade constant speed props.
Performance
PA-44-180 - Max speed 311km/h (168kt), max cruising speed 309km/h (167kt), long range cruising speed 280km/h (151kt). Initial rate of climb 1200ft/min. Service ceiling 17,100ft. Range with reserves 1630km (880nm).
PA-44-180T - Max speed 363km/h (196kt), max cruising speed 343km/h (185kt), long range cruising speed 293km/h (158kt). Initial rate of climb 1290ft/min. Range with reserves 1520km (820nm).
Weights
PA-44-180 - Empty 1070kg (2360lb), max takeoff 1723kg (3800lb).
PA-44-180T - Empty 1116kg (2461lb), max takeoff 1780kg (3925lb).
Total Seminole production through to end 2004 amounted to 672, including 86 Turbo Seminoles.
The Piper PA-44-180 Seminole is really the only twin currently being built in the USA that is being marketed almost directly for the training role. Piper is still one of the most trusted brand names in general aviation with a range of aircraft from the single Warrior–designed mainly as an ab-initio trainer–to the turbo-prop Meridian personal or business aircraft.
The PA-44 Seminole started life back in 1978 as a four seat twin-engined aircraft built around the well proven PA-28 Cherokee and later Warrior fuselage. The single engine was replaced with a streamlined nose section while the wings were redesigned to mount twin Lycoming O-360 four cylinder engines. The wing plan-form retained the tapered outer panels that were introduced on the Warrior model of the PA-28.
Using essentially the aft fuselage of the Arrow IV, the Seminole also inherited the all-moving horizontal T-tail tailplane as well.
In the latest variants of the Seminole, Piper has installed twin Lycoming engines so that the propeller rotation is what is called counter-rotating; that is, each engine rotates in the opposite direction to the other.
This opposing rotation avoids one of the problems in handling single engine failures in a light twin: failure of the critical engine. The critical engine is the engine that, should it fail, will cause the biggest yawing effect on the aircraft.
If both engines rotate clockwise as in a normal Lycoming installation (as viewed from the rear), then the combined thrust line would be slightly offset to the right side of the aircraft’s centreline. Therefore, should the left engine fail, the yawing effect would be greater than if the right engine had failed and more rudder would be required to offset this yawing tendency.
By installing engines with opposite directions of rotation, the thrust lines can be kept closer to the aircraft’s centreline.
Lycoming manufactures the 180-horsepower O-360 engine that is fitted to the PA-44-180 Seminole in two variants that rotate in opposite directions. The right engine being a LO-360-E1A6D that rotates counter-clockwise as viewed from the rear. There is no gearbox required, just two different model engines and two different propellers to cater for the counter rotation.
The Seminole has the same window and cabin arrangement as the Warrior, but it gets its T-tail from the Arrow IV. The all-moving horizontal stabilator has a near full span trim tab across the trailing edge. This tab is an anti-servo tab; that is, when the tailplane is deflected, say, upwards, the tab deflects further thereby tending to drive the tailplane back towards the neutral position.
This action reduces the tendency for the pilot to over-control in pitch because of the large effectiveness that an all-flying stabilator has over pitch authority.
The rudder, which is fitted with a large manually activated trim tab that is also an anti-servo tab, is also a little larger in area than its Warrior ancestor with the larger area required for directional adequate control should an engine failure occur. One advantage of such a large rudder and tab is that it decreases the Minimum Control Speed Airborne (VMCA) to be actually lower than the stall speed.
The trailing edge flaps are of the simple hinged design the same as the Warrior and are operated similarly by a mechanical system from the floor mounted handle; simple and reliable as proven for years in the Warrior design. Each wing flap section extends under the aft part of each engine nacelle so that no part of the flap is wasted by an intruding engine nacelle’s streamlined shape.
The Seminole sits atop a conventional retractable tricycle landing gear. The gear is hydraulically retracted with the hydraulic system being electrically powered. Raising the gear switch to UP powers the pump to supply pressure to raise the gear until it is retracted. Once the gear is up, the pressure is locked in the line to hold the gear retracted, there are no mechanical up-locks.
To lower the gear in an emergency situation, you only need to pull the Emergency Gear Extension knob on the instrument panel and the hydraulic pressure is released from the system and the gear will free fall and with the help of springs and gravity will lock in position.
To ensure that the nosewheel is fully lowered, there is small convex mirror on the inboard side of the left engine cowl so that the pilot can see the nosewheel when fully extended. The usual three green lights on the panel indicate when each landing gear leg is locked down.
To back up the indications and also to remind the pilot if he has forgotten to lower the gear, a warning horn will sound when the throttles are retarded to a low MAP.
The nosewheel is steered through the rudder pedals via a direct link with some spring balancing to balance any shock loadings, but to all intents and purposes, it is a direct link. The steering forces are quite light and with the toe-operated disc brakes, there is no problem in ground handling.
Interior Designs
Stepping into the Seminole was like getting back in touch with an old friend, and I was immediately familiar with Piper’s layout of controls; although most were somewhat more modern than the late 1960s Cherokee 140 that I had learnt to fly in.
The centre-mounted mechanical flap handle was still there but the coffee grinder style ceiling mounted elevator trim handle was gone.
Adjusting the seat forward was done by sliding the seat forward on the floor rails and locking it into position with a handle across the lower front of the seat.
Flying out of whack:-
At 5000 feet and with the right engine set in this condition, we were able to achieve a rate of climb of 300 fpm at 88 KIAS whilst holding 5o of bank toward to the left. Rudder forces weren’t that heavy to maintain the skid ball centered.
After restoring symmetrical power, I checked the roll rate in some turn reversals from 45o to 45o with fairly normal rates of 3-4 seconds.
The descent back to Moorabbin was somewhat drawn out as we kept the power set at 18 inches and 2200 RPM to keep the landing gear warning horn from sounding. This resulted in a descent at 140 KIAS and 500 fpm.
Entering the circuit area, the first landing was demonstrated to me from a long straight-in approach.
After the touch-and-go, my attempt from the next circuit resulted in a go-round from the flare. After having approached at 80 KIAS and while approaching the flare, I began to reduce the power and raise the nose to reduce the rate of descent.
Like on take-off, I found the stick forces a little higher than I had expected and when the ground was still approaching at a high rate, I over-flared and decided that the better decision was to go around.
The engine response was immediate and we were quickly climbing away for another attempt. The full-stop landing was much better. On landing I found the braking to be very efficient with relatively light forces; this made it easy to make the desired exit taxiway.
In all I found the Seminole to be a very capable twin trainer; it doesn’t have the world beating performance to leave your stomach back on the runway as you launch airborne or to exhibit single engine rates of climb to compete with a modern single engine aircraft; this is not its role.
The role of the twin trainer is to provide the student with a platform where the pilot can learn about how to handle problems associated with twin operations whilst flying the aircraft in the various phases of flight, and with really only one other competitor in the market place, the 30-year-old design competes well now it has modern avionics fitted.
The Seminole offers the reliability of all-metal construction that any LAME around the bush can fix as compared to composite structures, which–although becoming increasingly more prevalent–require a bit more specialised skills to repair. After 30 years of construction, there must be something right in the original design.
A similarly equipped 2012 Seminole with Garmin G500 will set you back between AUD$740-750,000 (incl. GST) based on current exchange rates. If you want to add some weight to the aircraft, even air-conditioning is available as an option. More information can be obtained by contacting Brian Jones at Piper Australia Aircraft
Sukesha Mishra
Marketing Trannie at AeroSoft
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