Piper announced the end of PA-30 production in 1970 and introduced a new PA-39 line. Basically a PA30, the PA-39 featured contra-rotating engines and a slight modification to the wings.
Three models were available:
Standard Model
Custom As Standard Model, with Piper Truespeed Indicator, vacuum system with dual engine driven vacuum pumps (dry), dual vacuum gauge, dual 70A engine driven alternators, heated pitot tube and full flow oil filters. Advanced instrument panel with 3in pictorial gyro horizon, 3in directional gyro, rate of climb indicator, OAT gauge, gyro air filter, inertial shoulder harness for two front seats, Piper pictorial turn rate indicator + 47 lb.
Sportsman As Custom Model, with Piper External Power, glare ban instrument lights, fifth & sixth family seats, Palm Beach interior with leather upholstery, four headrests and window curtains + 83 lb.
The 160 hp Lycoming IO-320 B version of the Twin Comanche was produced in limited numbers, all models were certified under FAA A1EA.
Some 155 were built before the 1972 flood at Lock Haven when it was decided not to build any more.
PA-39 Engines: 2 x Lycoming IO-320 B1A, 160 hp Props: Hartzell, Constant speed, full feathering, counter rotating Wingspan: 35 ft 11 in / 35 ft 9.5 in o/tip tanks Length: 25 ft 2 in Height: 8 ft 3 in Wing area: 178 sq.ft Tailplane span: 12 ft 6 in Fuel capacity: 90 USG / 120 USG w/tip tanks Stall: 69-70 mph Baggage: 200 lb Loaded weight: 3725 lb
PA-39 C/R Engines: 2 x Lycoming IO-320 B1A, 160 hp / 119kW Props: Hartzell, Constant speed, full feathering, counter rotating Wingspan: 35 ft 11 in (19.97m) / 36 ft 9.5 (11.22m) in o/tip tanks Wing area: 178 sq.ft Length: 25 ft 2 in (7.67m) Height: 8 ft 3 in / 2.51 m Tailplane span: 12 ft 6 in Empty weight: 2270 lb (1029kg) MTOW norm: 3600 lb (1633kg) MTOW w/tip tanks: 3725 lb (1690kg) Fuel capacity: 90 USG / 120 USG w/tip tanks Baggage: 250 lb / 113 kg Max speed SL: 205 mph Cruise speed SL eco: 181-188 mph Cruise speed SL norm: 198 mph / 172 kt / 319 kph Cruise speed 8000ft: 194 mph Cruise speed 10,000ft eco: 166 mph Stall: 69-70 mph Climb rate: 1460 ft/min / 445 m/min SE Climb rate: 260 ft/min Service ceiling: 20,000 ft / 6095 m SE service ceiling: 7100 ft Takeoff run: 940 ft Takeoff run to 50ft: 1530 ft Landing run from 50ft: 1870 ft Landing run: 700 ft Range norm fuel: 830 mi / 720 nm / 1335 km Range eco: 1110 mi Range max: 1200 mi / 1042 nm / 1930 km Baggage compartment: 20 cu.ft (0.57cu.m) Seats: 4-6
39 Turbo Cruise 12,000ft: 228 mph Cruise 12,000ft eco: 186-193 mph Stall: 69-70 mph Climb rate: 1290 ft/min SE Climb rate: 225 ft/min Service ceiling: 25,000 ft SE service ceiling: 12,600 ft Takeoff run: 990 ft Takeoff run to 50ft: 1590 ft Landing run from 50ft: 1900 ft Landing run: 725 ft Range 12,000ft: 1090 mi Range 12,000ft eco: 1485 mi Range 12,000ft max: 1535 mi Range 24,000ft: 1270 mi Range 24,000ft eco: 1670 mi Range 24,000ft max: 1710 mi Empty weight: 2416 lb Baggage: 250 lb Loaded weight: 3725 lb
PA-39 B Turbo Engines: 2 x Lycoming IO-320 B1A, 160 hp Props: Hartzell, Constant speed, full feathering, counter rotating Wingspan: 35 ft 11 in Length: 25 ft 2 in Height: 8 ft 3 in Wing area: 178 sq.ft Tailplane span: 12 ft 6 in Max speed SL: 240 mph Service ceiling: 30,000 ft SE service ceiling: 19,000 ft Range norm: 1090 mi Range w/tip tanks: 1360 mi Empty weight: 2408 lb Baggage: 250 lb Loaded weight: 3725 lb
Piper canvassed 10000 flying instructors before it built the “ultimate” training machine for the seventies. A cantilever low-wing monoplane with fixed tricycle landing gear, a T-tail, and side-by-side enclosed accommodation, it was powered by an Avco Lycoming O-235-L2C engine, designated Piper PA-38-112 Tomahawk. The Tomahawk was designed around minimalism and low initial cost (around US$18,000 in 1978) and low ongoing costs.
First flown in mid-1973, Piper’s Tomahawk received FAA type certification (FAA A18SO) on 20 December 1977. The T-¬tail trainer was certified in both the normal and utility categories, and the production lines started rolling in January 1978. The FAA temporarily suspended the airworthiness certificate of Piper’s Toma¬hawk trainer, grounding over 700 Toma¬hawks because of magneto failures. For simplicity, the ailerons and flaps were attached by piano wire hinges and the doors were held closed and locked by wire.
Fitted with a NASA created GA(W)-1 aerofoil, the Tomahawk’s heavy flight controls were intended to impersonate a bigger aircraft. The three position flaps, 34 deg, 21 deg, and up, is normally not used for takeoff. The wing has a fatigue limit of 11,000 hrs and modifications can increase that by 5000 hrs. One mod is to rivet a reinforcement plate to the wing’s spar plug.
Leading edge stall/airflow strips were installed on the aircraft’s wing to temper the stall/spin characteristics and the high crash/fatality rate dropped off noticeably. A 1983 AD required the installation of both inboard and outboard leading edge airflow strips.
Improvements introduced as standard in 1982 resulted in redesignation as the PA-38-112 Tomahawk II. The Tomahawk II introduced bigger wheels, and cured a nose wheel shimmy problem of the original.
Because of economic conditions production was suspended at the end of 1982, at which time 2,519 had been built, and output was nearing 200 units per year.
Piper hoped that it would be possible to resume production during 1984. This was not the case as the Tomahawk was one of the types most affected by the product liability laws and was already struggling to find a market.
Piper announced in 1972 a completely new version of the PA-25 Pawnee agricultural aircraft which introduced a more powerful Continental Tiara 6-285 flat-six engine of 213kW, a new cantilever wing, new safety features, filtration of the air entering the pilot’s ventilated and heated cockpit, and a larger standard chemical hopper of 0.85cu.m or, optionally, 1.08cu.m capacity. First introduced in Piper’s 1973 model year, over 350 were built up till 1977, all powered by a 285 hp Conti¬nental Tiara engine.
The Brave has a number of innovations to distinguish it from the earlier models of the type. One of the first differences evident is the lack of wing struts, fibreglass leading edges, and the fuel tanks are filled with a plastic foam like “infinite baffle” which is intended to reduce fuel movement and reduce the potential of fire. For the same reason the fuel lines are located behind the main spar. The rear fuselage is “pressurised” from a vent on the tail fin which acts to “push” the super out of the rear fuselage. The system is designed to keep 90% of the dust and dirt out of the fuselage and the easily removable panels make the remaining 10 per cent easy to get at.
A much larger ag aircraft than the original Pawnee, the Pawnee Brave was underpowered in its original 285 hp version. A 300 hp model was introduced in 1977. Designated Piper PA-36 Pawnee Brave, the new model began to enter service in 1973, and in 1977 an additional version with a 300 hp / 224kW Avco Lycoming IO-540-K1G5 engine became available, the designations of these two aircraft then becoming PA-36 Pawnee Brave 285 and PA-36 Pawnee Brave 300.
In 1978 the 300 hp aircraft became the standard model, and a new PA-36 Pawnee Brave 375 being introduced with a 280kW Avco Lycoming IO-720-D1CD flat-eight engine, equipped with the larger of the two chemical hoppers as standard. The engine was a detuned 400 hp Lycoming
These were to remain in production with Piper until rights for both versions of the PA-36 were acquired by WTA Inc. in 1981. This latter company was marketing this agricultural aircraft in two versions, the version with the 280kW engine now being the basic model and redesignated PA-36 New Brave 375. It was available optionally with a 298kW IO-720-D1C engine under the designation PA-36 New Brave 400.
WTA Inc received from Piper rights to PA-18-150 Super Cub lightplane and PA-36 Brave agricultural aircraft; 250 Super Cubs built before becoming once again Piper type, while PA-36 produced as New Brave.
Pawnee Brave Engines: Continental 6-285-C, 285 hp Wingspan: 39 ft 0 in / 11.89 m Length: 27 ft 4.25 in / 8.34 m Empty weight standard: 2050 lb / 930 kg Empty weight sprayer: 2170 lb / 984 kg MTOW weight normal: 3900 lb / 1769 kg MTOW weight restricted: 4400 lb / 1996 kg Wing loading: 17.3 lb/sq.ft Pwr loading: 13.68 lb/hp Equipped useful load: 1803 lb Fuel cap: 522 lb Payload max fuel: 1281 lb Working speed: 117 kt / 135 mph / 217 kph 75% cruise: 128 kt Range max fuel 75% pwr: 531 nm/ 4.2 hr Service ceiling: 13,000 ft Working endurance: 5 hr Stall: 54-62 kt ROC: 790 fpm Min field length: 1650 ft Hopper cap: 225 USG / 30 cu.ft / 0.85 cu.m / 852 lt Opt hopper cap: 275 USG / 38 cu.ft / 1.08 cu.m / 1041 lt / 1900 lb / 862 kg Cockpit width: 3 ft 2 in / 0.97 m Seats: 1
PA36-300 Brave 300 Engine: Lycoming I0-540-KIGS, 300 hp / 224kW Wingspan: 11.89 m / 39 ft 0 in Length: 8.34 m / 27 ft 4 in Height: 2.29 m / 8 ft 6 in Wing area: 20.96 sq.m / 225.61 sq ft Hopper Cap: 30 or 38 cu.ft Wing loading: 17.3 lb/sq.ft Pwr loading: 13 lb/hp Max TO wt: 3900 lb Empty wt: 2180 lb Equipped useful load: 1673 lb Payload max fuel: 1157 lb Range max fuel/ 75% pwr: 480 nm/ 3.9 hr Service ceiling: 12,000 ft 75% cruise: 123 kt / 229 km/h / 142 mph Working speed: 103 kt Stall: 54-63 kt ROC: 770 fpm Min field length: 1650 ft Fuel cap: 516 lb Seats: 1
For 1972 Piper introduced the six/seven-seat Piper PA-34 Seneca which, basically, was a twin-engine version of the Cherokee SIX with retractable tricycle landing gear, a new fuselage structure and power provided by two 200 hp / 149kW Avco Lycoming IO-360 flat-four engines.
Early models, the Seneca I, handled awkwardly and were slower than expected and the Seneca II incorporated improvements including: turbo-charging, larger and redesigned ailerons and improved stick forces. For 1975 149kW Continental TSIO-360-E turbocharged and counter-rotating engines were introduced and the landing gear was strengthened for operation at higher gross weight, the designation then changing to PA-34-200T Seneca II.
Many Seneca I have been upgraded to Seneca II standard featuring turbo-charged engines and improvements to ailer¬ons, rudder and the stabilator to improve handling.
In 1982 the Seneca II was superseded by an improved PA-34-220T Seneca III. A total of 28 improvements changed the II into the III, and while most of these are cosmetic, the two most significant are further increases in available power, and weight – most of which means useful load. A five minute take-off power rating increases 20 hp to 220, an rpm increase from 2575 to 2800, and an increase in MTOW of 180 lbs. This translates to a 190 lbs increase in useful load. The Seneca III has Continental TSIO-360-KB turbocharged and counter-rotating engines.
The PA-34-220T Seneca III remained in production in 1984.
Seneca III
During 1976-77 Piper signed an agreement with the Polish foreign trade association Pezetel under which P.Z.L. Mielec will assemble/manufacture the Seneca for sale in eastern Europe. Designated in Poland as the P.Z.L. Mielec M-20 Mewa (Gull), the first Polish-built prototype was flown on 25 July 1979. The production version M-20 03 was one of the very few light-twins on the market.
It was reported in February 1981 that the Forca Aerea Brasileira had placed an order for a follow-on batch of 20 EMB-810 (Seneca II) for liaison work, 11 having the Robertson STOL modifications. The EMB-810 is designated U-7 by the FAB, the initial order having called for 12 aircraft.
In 1994, the “new” Piper Aircraft company introduced the Seneca IV, having acquired its license on November 17, 1993. This model is similar to the Seneca III offering small improvements such as modifying the engine hood for better cruise performance. It still continued to use the counter-rotating technique with the Continental IO-360 and Continental TSIO-360-KB engines and the maximum weights remained the same.
In Brazil, versions with the economical Continental IO 360 aspirated Seneca II (two-bladed propeller) and Seneca III (three-bladed propeller) were a major selling success in the 1970s and 1980s, leading to a licensing agreement between Piper and Brazilian manufacturer Embraer, on a new EMB-810 D and Cuesta designation for the same basic design. Subsequently, the manufacture of the aircraft was transferred to the subsidiary of Embraer, Indústria Aeronáutica Neiva.
Neiva EMB-810D Seneca III
The Seneca IV was the last Piper produced under license by Embraer and that agreement terminated in 1996.
PT-VSH – Neiva EMB-810D Seneca III
A total of 4,464 Seneca were delivered by 1 January 1991.
New Piper continued production of the Seneca V.
Certification was under FAA A7SO for:
PA-34-200 34-7250001 to 34-7250189 when kit number 760607 is installed. 34-7250190 to 34-7250214 when kit number 760611 is installed. 34-7250215 to 34-7350353 34-7450001 to 34-7450220
PA-34-200T Seneca II All, except with kit number 764-048V or 765-110 installed.
PA-34-220T Seneca III All, except with kit number 764-099V or 766-203 installed
PA-34-220T Seneca V 3440991 and up, except with kit number 766-632 installed or Avidyne Entegra System installed
PA-34-200 Engines: Two 200hp Lycoming IO-360 Wingspan: 38’11” Length: 28’6″ Useful load: 1600 lb Max speed: 198 mph Cruise:183 mph Range: 940-1130 mi Ceiling: 20,000′ Seats: 6-7 No. built: 933
PA34-200T Seneca II Engines: 2 x Continental TSIO-360-E, 200 hp at sea level, 215 hp at 12,000 ft Seats: 6/7 Wing loading: 22 lb/sq.ft Pwr loading: 11.4 lb/hp Gross wt: 4570 lb Empty wt: 2788 lb Equipped useful load: 1654 lb Payload max fuel: 916 lb Range max fuel/ 75% pwr: 864 nm/4.5 hr Range max fuel / 55% pwr: 998 nm/ 6.1 hr Service ceiling: 25,000 ft Cruise 75%: 190 kts @ 20,000 ft 55% cruise: 165 kt Vmc: 70 kt Stall: 61-63 kt 1.3 Vso: 79 kt ROC: 1340 fpm SE ROC: 225 fpm @ 90 kt SE Service ceiling: 13,400 ft Min field length: 1568 ft Fuel cap: 588/738 lb Undercarriage: retractable T/O dist (50 ft): 1240 ft Ldg dist (50 ft): 1860 ft Number built: 2588
PA34-220T Seneca III Engine: 2 x Continental, TSIO-360KB & LTSIO-360KB, 220 hp @ 2800 rpm (5 min), 200 hp @ 2600 rpm continuous TBO: 1800 hr Prop: Hartzell 2 blade, constant speed 76 in Seats: 6/7 Length: 28.5 ft Height: 9.9 ft Wingspan: 11.86 m / 39 ft 11 in Wing area: 209 sq.ft Wing aspect ratio: 7.4 Max ramp wt: 4773 lb Max take off wt: 4750 lb / 2155 kg Standard empty wt: 2875 lb Max useful load: 1898 lb Max landing wt: 4513 lb Wing loading: 22 lbs/sq.ft Power loading: 11.4 lbs/hp Max useable fuel: 738 lb Climb rate: 1400 fpm @ 89 kt Climb gradient: 903 ft/nm Rate of climb @ 8000 ft: 1275 fpm Certificated ceiling; 25,000 ft / 7620 m SE rate of climb: 240 fpm @ 92 kt SE climb gradient: 157 ft/nm SE ceiling: 12,300 ft Max speed: 196 kt Cruise @ 65% power @ 8,000ft: 164 kt Cruise @ 65% pwr @ 18,000 ft: 180 kt Fuel flow @ 65% power @ 18,000ft: 121 pph Endurance @ 65% power @ 18,000ft: 5.8 hr Stalling speed clean: 65 kt Stall speed gear/flaps down: 62 kt Turbulent air penetration speed: 140 kt Retractable undercarriage Cabin length: 125 in Cabin height: 49 in Cabin volume: 195.3 cu.ft Fuel capacity: Std: 371 lt, Optional: 484 lt TO dist: 920 ft Landing dist: 1218 ft
Piper PA34 – 220T Seneca IV Engines: 2 x Teledyne Continental TSIO / LTSIO 360 KB, 232 hp Length: 28.576 ft / 8.71 m Height: 9.908 ft / 3.02 m Wingspan: 38.911 ft / 11.86 m Wing area: 208.714 sq.ft / 19.39 sq.m Max take off weight: 4749.6 lb / 2154.0 kg Weight empty: 2853.3 lb / 1294.0 kg Max. payload weight: 1920.6 lb / 871.0 kg Max. speed: 196 kt / 363 km/h Landing speed: 64 kt / 119 km/h Cruising speed: 193 kt / 357 km/h Take off distance: 1211 ft / 369 m Landing distance: 1978 ft / 603 m Service ceiling: 25000 ft / 7620 m Wing loading: 22.76 lb/sq.ft / 111.0 kg/sq.m Range: 990 nm / 1833 km Crew: 2+4
2007 Piper PA34-220T Seneca V Engines: Continental TSIO-360-RB, 220 hp TBO: 1800 hr Fuel type: 100/100LL Propeller: Hartzell CS/2-blade Landing gear: Tri./Retr. Max ramp weight: 4773 lb Gross weight: 4750 lb Landing weight: 4513 lb Empty weight, std: 3393 lb Useful load, std: 1380 lb Usable fuel, std: 122 USgal Payload, full std. fuel: 648 lb Wingspan: 38 ft. 10 in Overall length: 28 ft. 7 in Height: 9 ft. 11 in Wing area: 208.7 sq. ft Wing loading: 22.8 lbs./sq. ft Power loading: 10.8 lbs./hp Wheel size: 6.00 x 6 Seating capacity: 6 Cabin doors: 2/3 Cabin width: 49 in Cabin height: 42 in Cruise speed 75% power: 197 kt Cruise speed 65% power: 190 kt Fuel consumption 75% power: 26.4 USgph Fuel consumption 65% power: 22.8 USgph Cruising range: 828+ nm Vso: 64 kt Best rate of climb (SL): 1462 fpm Service ceiling: 25,000 ft Service ceiling, SE: 16,500 ft Takeoff ground roll: 1143 ft Takeoff over 50 ft. obstacle: 1707 ft Landing ground roll: 1400 ft Landing over 50 ft. obstacle: 2180 ft
PZL Mielec M 20 Mewa Engines: 2 x Teledyne Continental TSIO 360 KB, 217 hp Length: 28.609 ft / 8.72 m Height: 9.908 ft / 3.02 m Wingspan: 38.911 ft / 11.86 m Wing area: 206.454 sq.ft / 19.18 sq.m Max take off weight: 4564.4 lb / 2070.0 kg Weight empty: 2910.6 lb / 1320.0 kg Max. speed: 194 kts / 360 km/h Landing speed: 60 kts / 112 km/h Cruising speed: 168 kts / 311 km/h Initial climb rate: 1496.06 ft/min / 7.60 m/s Service ceiling: 25000 ft / 7620 m Wing loading: 22.14 lb/sq.ft / 108.0 kg/sq.m Maximum range: 990 nm / 1833 km Range: 670 nm / 1240 km Crew: 1+6
In 1967 a single Comanche, N4600Y, was modified by Swearingen with a pressurised cabin.
The prototype, powered by a 260-hp Lycoming TIO-540 engine and equipped with Twin Comanche landing gear, tail and wings and a new fuselage, was first flown on 11 March 1967.
The Comanche crashed on takeoff from Lock Haven 23 March 1967 when the pilot had problems with the electric nosewheel. The project was then cancelled and removed from the Register in 1969.
The Piper PA-32-3M was basically a PA-32 Cherokee based prototype modified as a Trimotor aircraft with two 115-hp Lycoming O-235 engines fitted to the wings, for development of the PA-34 Seneca at Vero Beach FL. in the early ’70s. This prototype significantly helped many other development projects at Piper.
It was an early attempt to convert the PA-32-260 Cherokee 6 into a simple, low-cost trimotor, retaining the fixed gear and using fixed-pitch props. This was actually tested by adding two 115 hp engines to the wings and throttling the Cherokee 6’s 260 hp engine back to simulate a third O-235 for a total of 345 hp.
Performance on all three engines was fine, but engine out performance was not. Switching the 115 hp engines for 150 hp units solved that problem, but speed was now so high on 450 hp that controllable-pitch props were needed, defeating the original purpose. That model eventually became the Seneca, but with two larger engines, variable-pitch props and retractable gear.
