Based on 150 hours per year the 421C has lower DOC's than a KAC90. A 421C in "GOOD" condition is 600 per hour based on 100 hours per year. A C90 will be 1500 plus? Based on 100 to 150 hours per year.

I flew my wife and family in a Black Hawk C90 on several long trips and they did not like it. There was not enough baggage space and the cabin was louder than a 421C. They also did not like the narrow cabin.

I haven't owned either but operated a C340 for about a year and nearly pulled the trigger on a C421. I spent a great deal running all the #'s, talking to mechanics and talking to many owners of both. My personal conclusion was that the overall cost of owning a C421 was perhaps 10% more than a C340, making the decision between the two a no-brainer for me. The 414's weren't appealing due to higher acquisition price and engines which I felt were under powered (same engines on C340 on a much bigger / heavier airframe) and the biggest appeal to the C421 (besides the enormous cabin) was the very quiet geared engines.

I focused my efforts on the C421 but after talking to many, many owners I simply couldn't get past the exceptionally hard to predict mx costs. Engines aside, you can spend an enormous amount of $$ on mx on these birds and still have another enormous bill right around the corner.

At the end of the day, my mission (90% single occupant, 10% mult-pax trips and roughly 350 hrs / yr) doesn't match up well with a C421 and I went an entirely different route. Yours seems to match it very well. I would consult with as many owners as you can regarding their very honest experiences & costs operating these birds. Also talk to several shops who specialize in Twin Cessnas - TAS in Defiance, OH is one but there are many others.

I still have a longing for a C421 and would recommend them to anyone who is looking for a very roomy, comfortable cabin with almost endless baggage space. I think you just need to go in eyes wide open and be prepared for some very hefty on-going mx bills.

I would not call a 414A with 335hp underpowered. The wing is glider like and climbs just fine on 335hp and really hauls on 670hp. IIRC it will hang around FL200 on a single engine. IMHO best light twin ever created.

OK perhaps calling the 414 underpowered isn't fair or accurate. I should also say I never flew a 414, so I can't comment with direct experience. However I found the C340 to be rather loud from the pilots seat (louder than my Seneca), although quieter in the back of the cabin. My assumption is that the experience in a 414 would be similar.

My ride in the C421 (both up front and in back) was an entirely different experience than the C340. It's fantastically smooth and very quiet in comparison. Those differences were enough for me to eliminate the 414 from consideration.

Can you elaborate on the "enormous amount of $$ on mx"? I hear this a lot from people about pressurized twins but I never quite understand what the expensive items are other than the engines/props. I'm currently in the market for a 340 or a 421B/C so this thread is of great interest to me. Thanks

Another point of feedback that I forgot to mention...

When I showed my wife the C340 (in the hangar), she absolutely loved it. She really liked the cabin and space and roominess compared to our Seneca. Strangely enough after flying in it, she hated it. I couldn't get her in it again afterwards.

I couldn't get her to verbalize exactly what it was that bothered her but the several times that we talked about it, I think the 'jerkiness' of the Cessna 400 autopilot and the relatively high cabin vibrations (up front) made her feel uneasy. She actually prefers the ride in the Seneca vs. the C340, despite the significant difference in room and capacity.

Although she never flew in a C421, I think she would've felt much different about it.

OK perhaps calling the 414 underpowered isn't fair or accurate. I should also say I never flew a 414, so I can't comment with direct experience. However I found the C340 to be rather loud from the pilots seat (louder than my Seneca), although quieter in the back of the cabin. My assumption is that the experience in a 414 would be similar.

My ride in the C421 (both up front and in back) was an entirely different experience than the C340. It's fantastically smooth and very quiet in comparison. Those differences were enough for me to eliminate the 414 from consideration.

To some extent, this is just a matter of size/complexity mostly unrelated to pressurization per se

Compared to a typical A36 you pick up
- heater
- air conditioner
- structural windows
- heated prop
- boots
- turbocharger
- radar



A 421B has 12 cylinders, 24 spark plugs, 9 fuel pumps, two landing light motors, etc. Even if every item has a 500hr MTBF, when you have 4X as many things on your plane, more stuff breaks

Pressurization and the accompanying ice protection add cost. The windshield is a $10K item (part only, no labor). Boots have to be replaced every so often and cost something like $20K for the whole plane. Heated props don't last very long without some maintenance. Heated stall warning switches are expensive. It's death by 1000 cuts.

Can you elaborate on the "enormous amount of $$ on mx"? I hear this a lot from people about pressurized twins but I never quite understand what the expensive items are other than the engines/props. I'm currently in the market for a 340 or a 421B/C so this thread is of great interest to me. Thanks

From my experience owning a C425, which is a 421 with PT6A engines, you can spend a lot of $s troubleshooting gremlins. Pressurized twins have more systems and more stuff to fix.

Things like:

- Air conditioning system
- Boots
- Pressurization leaks and whistles
- Retractable landing lights whose gears strip
- Glass electrically heated pilot windshield
- Heated props

It helps to have a shop with experience in the type. Educating a shop will cost you even more.

[Edit] I see others have similar lists. You just need to go into these aircraft with your eyes open and sufficient $ reserves.

There are many here on this forum that can do much better justice answering this (and already have) than I can. However, as a couple examples...

I nearly bought a C421B that recently had a great deal of mx completed by a highly regarding twin cessna shop. The total bill was $90K (the engines / props weren't touched) and my thought was that with that much mx being recently done, certainly it wouldn't need a thing for a LONG time. When I looked at the deferred items list, many of which I felt shouldn't have been deferred, the airplane still needed another $30K of mx. Even at that, I saw another $100K in various upgrades (mostly avionics & autopilot) that I wanted to do and all that still didn't cover the pilot's windshield which was also in need of replacement.

Another owner I spoke to decided to maintain his C421 to the highest degree possible in order to maintain an exceptionally high dispatch rate. He spend $50K at a highly reputable twin cessna shop and the went back for another $50K less than a year later (this was on a bird that already had the 'catch up' items addressed when he bought it). The very high mx bills kept on coming over a period of several years. When I asked him if all this high degree of mx improved his dispatch rate he said 'unfortunately No'.

As mentioned above, these airplanes simply have MANY, MANY systems and parts and each one only lasts so long. With more systems comes higher maintenance. There's just no way around it.

414A isn't getting any love up in here!!!!

Keep in mind maintenance costs have a lot to do with where you go to get it done. A lot of guys think paying 40k for an annual somehow means you have the best mechanic out there. In reality you got screwed. Find a good mechanic who does good work and be involved in your maintenance. If your not involved and you give them a blank check your going to get screwed.

I've had the 414A for 18 months and love it. 2000lb useful and pressurization cant be beat. I have the Ram VII conversation so power isn't a problem at all. Single engine performance is great. Cabin is really spacious and A/C works great.

2016 annual $6,700
2017 annual $7,500

Thank you all for your replies. This is why I love BT. You can post literally anything and get knowledgeable replies back. I think riding in one or multiple of these planes would be beneficial to some extent. We need to figure out which we like best. Have climbed around in a 421c and loved it. There's just something about looking out and seeing two huge engines strapped on your sides

I need to be visiting that mechanic. I've had only 1 annual on the 340, it was around 20k- but about 5k was stuff I wanted chased down that turned into many hours (ie, chasing down a wire for the courtesy light, which should operate with master off, took 10 hours, and was mis-wired). but I wanted it to work- so I paid for it.

I never flew, owned, or operated a 421. My assessment when i was looking (2 years ago), every shop I discussed it with told me the maintenance was more, insurance was more, and the airframes were 2x the price of the 340 airframes. I thought I could do a lot of flying for the 200k difference in capital outlay. plus, our whole family of 5 (and the dog) with baggage is around 725lbs, so we fit nicely in any of them.

either 340 or 421 are great platforms. but complex systems as mentioned can bite you. finding a good bird and knowing what to look for in a prebuy is critical.

Go for a ride in an Aerostar too - 90% single person - you get speed and comfort - plus a step-in pilot door. Try the 700

Bob