SENECA
The Seneca, a twin-engine 200 HP, Lycoming powered non-turbocharged aircraft was first certified in May 1971 and was considered a 7 place aircraft. The engines were counter-rotating. Maximum takeoff weight was 4000lbs for the earlier models and 4200 lbs for the later models with landing weight still at 4000 lbs. 93 gallons max usable.
The Seneca II was certified in July of 1974 and had two Continental powered turbocharged 200 HP engines. Critical altitude was about 11,000’. In other words it could produce maximum manifold pressure to that altitude. Its maximum takeoff weight was 4570 lbs and 4342 max landing. Maximum allowed fuel with optional tanks was 123 gallons.
The Seneca III, which was certified in December 1980, was an improvement over the II in that it could produce 220HP for 5 minutes. This allowed the maximum takeoff weight to increase to 4750 lbs and the landing weight increased to 4513, the same as on the Seneca IV and V.
The Seneca IV was certified in November 1993. This was considered a 6 place aircraft.
The Seneca V was certified in Dec 1996 and was able to produce 220 HP on a continuous basis. It continues to be considered a 6 place aircraft. Although it still had Continental engines, it came equipped with the Lycoming fuel injection system. The rudder trim tab was now a servo unit which meant that the trim tab automatically moved opposite the rudder movement which made engine-out work easier on the leg of the poor pilot. This aircraft came out with newer engine gauges. Engine induction air now comes from outside the cowling through a NACA scoop which causes the engines to run cooler.
QUIRKS
The Seneca continues to be nose heavy during landings. Some people land with only 25º of flaps for this reason.
If the pilot allows the nose to hit the runway hard on landing, it may cause a bolt in the nose section to break allowing the nose gear to collapse thereby ruining two propellers, causing the engines to be sent back to the factory and ruining parts of the under belly of the aircraft. If the bolt is only bent, it will be easier to break later with another hard landing.
This aircraft is a challenge to land in a gusty crosswind. The aircraft seems to respond slower to flight control inputs at slow speed than what most pilots are used to.
MY OPINION
The Seneca V is a pretty good airplane. The advantage it has over non-turbocharged twins is that will continue to climb on one engine even in the teens as it still produces 220 HP at those altitudes. What other piston twin engine built today will do that? The Seneca V with its 6 cylinders and 3 bladed props runs quite smoothly and fairly quietly. I’d still want a noise canceling headset if I flew one a lot. If you are new to the Seneca, be sure that you can land it consistently safely in gusty crosswinds and consistently main wheels first. The Seneca V is one of those rare airplanes that can takeoff and climb over a 50’ obstacle in a shorter distance than it can land from over a 50’ obstacle. Although it isn’t the fastest piston twin built (at least at the lower altitudes) it sure is a blast to climb it at Vyse with both engine at full power.
OBSERVATION - The Seneca V is still being built.