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PIPER SENECA I

The roomy, comfortable and relatively economical Piper Seneca is one of the biggest selling light twins of all times. tweaking and upgrading over the years have enhanced its basic charms so that over 30 years later it still leads the pack.

Piper introduced the seneca with considerable fanfare in 1971. Complete with "hershey bar" wingsit shared the stretched six to seven seat fuselage with the Cherokee six. all in all it was an impressive looking airplane for the time. The company did its best tp design the airplane for ease of operation and maintenance.

for example, the fuel system was as simple as could be: on, off or crossfeed selection for each engine. counter rotating engines and props were installed to minimize engine out control problems inherent in twin engine aircraft. sections of skin on the wings and fuselage were designed for quick removal during maintenance operations.

Unfortunately, the good looks, the full seating for six and well designed systems were forgotten in flight... The seneca's handling wasnt just truck-like, it was elephantine! prone to dutch roll, this tendency was only magnified by heavy and inssuficiently effective ailerons.

The lycoming engines (200 HP IO-360-C1E6 types) were prone to vibration, this lead to cracking spinnners and a high noise level inside the aircraft. Airworthiness directives also started to flow almost as soon as deliveries began. 3 ADs in 1972 amd 5 additional ADs in 1973.

933 piper senecas were delivered in the first three years of production.

PIPER SENECA II INTRODUCED

the piper seneca II was introduced in 1975 as a substantially re-designed model. with new engines, re-worked controls and some minor systems changes many of the shortcomings were addressed.

the 4 cylinder Lycoming of the seneca I was replaced with the 6 cylinder Continental TSIO-360-E. though rated at the same horsepower as the Seneca I engines - the turbo charged Seneca II could pump out 215 HP at 12,000 feet. single engine rate of climb was increased by about 100 feet per minute, and single engine ceiling increased to 13,400 feet thanks to the turbos. The engines were covered with larger more aerodynamic engine nacelles. gross weight was increased by 370 lbs over the Seneca I. The aileron span was also increased in the Seneca II, and the controls were more aerodynamically balanced which improved handling characteristics. Optional long range tanks, and even three bladed props were offered as options on the seneca II. Also the popular club seating option as introduced which improved cabin comfort.

The next series of improvments came in 1981 with the Seneca III.

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most of the above information is borrowed from "The aviation consumer's used aircraft guide vol. II"

In short the Seneca 1 - the original design - equipped with two 4 cylinder 200 HP IO-360-C1E6 engines was a good airplane, but suffered in performance and handling characteristics. Single engine performance was not all that great. basically the only differences between the Seneca I and the II are the turbocharged six cylinder TSIO-360-E engines and improved control surfaces with a few additional options like long range tanks and club seating. most of the refinements that came to the line between the seneca I and the seneca II dealt with improving handling and performance.

If you need some decent pictures to flesh out your talk with, you could try Airliners.net



TSC.

yep Rotty thats basically it.

the Seneca I was built - piper realized after a few years how to make it a better airplane, slapped on some better engines, changed the controls a bit and added a couple of options packages. -Thats it. same wings, same fuselage, same panel layout probably even the same colors and i doubt if one could sit a Seneca I and a Seneca II together on the ramp and tell the difference visually, i have flown I's II's and V's, and except for handling and a couple of minor procedural things they are all pretty much identical aircraft - except the V of course all shiny and new hehehe

Thanks guys, you have all been very helpful!

The really ironic thing is that I have a Seneca II standing in the hangar with all manuals and documents, but that teacher of mine sure must like the seneca I couse he wont change my asignment to seneca II...