Please, please, please do not buy the seneca I. If you want a twin to train in and build cheap hours, get an apache. If you want a one for 1-3 people to go places efficiently, twin comanche or travel air. Going places with more people, baron or seneca 2/3.

The seneca 1 is not only underpowered and inefficient, it's a candidate for the worst flying plane ever made. I wasted 2 years of my life building one from parts thinking i was making an inexpensive family hauler. When I got it going i achieved the low-cost build goal, but it wasn't a hauler and flew so poorly i couldn't stand it. I unloaded it and got a fixed gear PA32 instead, hauled more weight at nearly the same speed.

really, if this is just about twin hours, then 150hp apache burning mogas is your ticket.

Love my Seneca III about 6 hours into getting my multi rating on it. Definitely wouldn't recommend the engines in a training environment where it's constantly busy OR you don't have 1000% trust in the instructors to take good care of it.

From a numbers standpoint, take a look at how many people and how much stuff you want to take XC, where, and then what it looks like if you lose an engine. The below are all "book" numbers at gross, so de-rate appropriate based on age and condition:
- The Seneca I will climb 190 fpm at Sea Level, and has an OEI ceiling of 3600 ft.
- The Seneca III will climb OEI at 200-300 fpm and has a 13,000ft single engine ceiling.
- For fun, I put together a flight from Montrose, CO (KMTJ) at 5,795ft. The Seneca III will still climb 182 fpm at TO power or 141 fpm at MCP.

So for a dedicated trainer, Seneca I. If you want to go places with you friends and family, II-IV (excluding the 5 because it's like a 2 person airplane with all the luxury features).

A little more color, since you guys seem to be getting into it (and I'm learning a lot).

Twin Comanche - Fast, cheap - you can get CR props if you search hard enough - but too many Vmc accidents from that fast wing to trust MYSELF. I want the benefits of a twin with as few of the risks (please don't argue with me, I know you want to! - remember, it's my choice, my biases)

Travel Air - Went down this road putting a deposit on one, before I learned that the prop AD would cause a $40k expense at first inspection - PLUS, many insurers are looking at these as antique planes and won't write commercial on it. I love the TA's. But they didn't work out - or haven't. Finding a good one is also, uh...tough.

You guys are biased towards Barons. I get it - I own a beechcraft too. But not really a trainer, and very expensive to run, especially if your primary mission ISN'T getting far down the road with your family. If it was, that'd be the first choice, for sure.

So - Senecas. Parts and mx is easy to find, if not always cheap. the Seneca I is about as efficient as a twin gets (that's not a 1M diamond) and the III is about 22-24 g/hr. at 25 knots faster.

Look, I'll admit to having a jones for a twin for no real good reason. I got a trip coming up to Asheville. I *could* file in my super III and spend 5 hours each way and $700 in gas before whatever the FBO charges to park (if the wx is good) -- OR -- I could book a flight out of LGA for $400 round trip and sleep. Would another 40 knots change that decision? mebbe. Prolly not.

But who says I can't experiment with 50k risk to have a new challenge, maybe a new business and some fun? Not in aviation? Especially in aviation! Right?

BTW, this kind of fat chewing on the forums is part of that fun too..............

other than a twinkie, or travelair, or baron, or 310, or seneca 2/3...just about anything other than an apache ?

The seneca1 is the standard of how poor an airplane design can be if you set out to have a no-compromise loser

in the real world you will be cruising 10-15KTAS slower than a travel air on 2gph more fuel

The big problem that I have with the Seneca I is that you have a huge cabin you can't really use.

Engine out performance aside, the plane has a lot less horsepower than a 310 with as much cabin space.

The Continental TSIO-360 engine is just barely enough engine for a cabin that size, and it is really pushing the Cubic Inch to HP ratio. It is not a cheap engine to overhaul either.

The Seneca really would have been a better/cheaper plane with the Aztec engine on it. The Aztec engine is hard to kill even with a turbo. They pretty routinely go 3000 hours if a good engine is treated right, and 4500 hours without the turbo.

The Travel Air and Twin Comanche cabin is the right size for that engine, and VMC issues really don't apply with proper training.

I really wouldn't worry about the CR kit on the Comanche. You just have to be patient to find a good one with either the PA30 or the BE95. Or with pretty much any of these old planes.

As a former Seneca II owner and operator, who also has Seneca I time:

DO NOT BUY A SENECA I.

Unless maybe, you’re going to rent it to others to train in.

I bought a Seneca II and got my multi engine rating in it. The I flew it for about a decade. You will not harm it getting your multi ticket in it. You will not harm it doing recurrent training and BFR and IPC in it either.

The TSIO360EB is actually pretty robust. If properly looked after and kept to about 65% power cruise, they last a long time with little trouble at all. The key is fly frequently and change the oil, be gentle with the throttles and you’ll be golden.

I found the Seneca II to be a very good traveling aircraft. Turbocharged engines and FIKI make it the least expensive “scheduled to arrive” aircraft.

In my opinion the TSIO360 is a good choice for this size of airplane. Mine had a very generous useful load and very good runway performance, climb and would maintain altitude above 12000 feet on one engine.

It isn’t a terribly fast airplane. But the typical for me was 170kts at 20gph total in the mid-teens altitudes.

My Columbia 400 will do 200kts or better on 15gph. I got it when I no longer needed the cabin and load carrying of the Seneca II.

I owned a Seneca III for many years and it was great Surburban. easy to load performed well, and had known Ice which is absolutely necessary in the Midwest for a working aircraft.

I would recommend it as a good honest simple aircraft that served me and my family well.

I trained in a Seneca I and it would hardly fly on one engine so a day VFR aircraft.


when I wanted to go faster I bought the Aerostar 602P 700 wonderful single engine performance, very fast, handled like an expensive European sedan, and pressurization but the Seneca had more room.

I had a Seneca I years ago (and later a couple of Seneca II's) the only thing I remember negative about the Seneca I was that mine used engine muffs for cabin heat and it made for some cold trips on occasion. Meaning the heat did not work very well--so if you are in a northern climate keep that in mind. Only multi airplane I have ever known without a gas heater. Todd

The Grumman GA-7 Cougar also used engine heat for the cabin. IIRC there's a STC to add exhaust heat to some other twins (I forgot which ones) as a supplemental/backup cabin heat source. When my Janitrol quit on a cold winter day coming back from Utah I could have used that.

Probably the best application of a Seneca 1 is a compressed 5 hour multi engine certificate training program. As mentioned, Action Air in Groton has been offering this program for many years and they are always sold out for 6 months.

I can not suggest a good argument for owning this plane for personal use. As you have seen, there are many better choices for higher performance twins that will not be subjected to the rental flight line.

Best of luck with your decision.

I can't believe no one has has just bluntly said it.

Senecas suck. Jesus, man. Get a Baron

Seneca II and up, better than a Baron for many reasons.

Seneca II and up, better than a Baron for many reasons.

I wouldn't say a Seneca II+ was better than a Baron although they do have a slightly wider cabin, but I wouldn't say they suck either.

If the training is just for you, the II and above will be fine. For a flight school with different instructors and students every hour the I is a better choice. For the family hauler the II+ is the only Seneca options.

The Seneca is very economical for a twin in cost to fly and maintenance.

Michael