best pressurized twin piston

pmiracing

pmiracing

Filing Flight Plan
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Nov 29, 2014
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15
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Mora, MN
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Display name:
luke
We are unfortunately in the market for a cabin class pressurized twin piston due to a gear collapse on our p Navajo. I have been eyeing 421's mostly but am interested in any input on other options. I loved our pa-31p but am shying away from them due to lack of parts and a&p's familiar with them(hench the gear collapse). I need similar useful load, pressurization, room and speeds to the pa-31p.
 
Maybe time to think about a PA-31T Cheyenne, or possibly the 2 models of the Cessna Conquest.??

Is the PA-31p the one with geared engines.??
 
If you need the space and useful load of the P-Navajo, you either want a 421B or C or a RAM VI/VII 414A. Support for them is still pretty decent.

If your budget allows it and it would fit the mission it might be worth looking at the various similarly sized turbopros - Cheyenne I/II, various King Air 90s, MU-2.

Zeldman said:
Is the PA-31p the one with geared engines.??
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Yes. TIGO-541 Lycomings.
 
Depending on actual load, the Aerostar may do the job. But it is a much faster plane.
The plane is still well supported by Aerostar Aircraft and the owners groups.

I miss mine.

Tim

Sent from my SM-J737T using Tapatalk
 
Ted DuPuis said:
If you need the space and useful load of the P-Navajo, you either want a 421B or C or a RAM VI/VII 414A. Support for them is still pretty decent.

If your budget allows it and it would fit the mission it might be worth looking at the various similarly sized turbopros - Cheyenne I/II, various King Air 90s, MU-2.



Yes. TIGO-541 Lycomings.
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Right now the budget doesn't allow for a turboprop.
 
tspear said:
Depending on actual load, the Aerostar may do the job. But it is a much faster plane.
The plane is still well supported by Aerostar Aircraft and the owners groups.

I miss mine.

Tim

Sent from my SM-J737T using Tapatalk
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I have looked at some Aerostar's online, but they look pretty small in the cabin. Also I believe usefull load is pretty low?
 
pmiracing said:
What do you hate about the 421? The 414 is a much smaller cabin isn't it?
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The 414 and the 421 are the same cabin. The primary difference is the 414 has direct drive TSIO-520s while the 421 has geared GTSIO-520s. The 421 got the straight wing (going from tip tanks) sooner in 1975 or 1976 (I forget which) when the 421C was introduced. The 414A went to the straight wing in 1978. Note the 421B and C both have the longer nose (which is good for more baggage space), but the 414 only got the longer nose with the A model. You need a RAM VI or RAM VII 414 (tip tank or A model) to get the same useful load as an equivalent 421.

We had a 1977 414 for 2 years. I specifically wanted a tip tank model with the short nose for a few reasons. First that's what would fit in my hangar (the 421B is much longer, and the 421C/414A have a much wider wingspan). Second I did not want the geared engines - they are higher maintenance and more prone to case cracking. There is debate about this on the Twin Cessna forum, but pretty much 421 owners (who've typically experienced case cracking themselves but ignore it) are the only ones who defend the engines. The engines are very smooth and very quiet, and you do get better performance. Third, I didn't want the straight wing as they do tend to have some extra maintenance issues, specifically regarding corrosion under the boots. The tip tank fuel system is a bit more complex but it's not inherently difficult to operate.

A 421B is the best purchase price value on the market if you can find a good one, but you may pay for it later with engine maintenance.

If you'd like to discuss I'd be glad to chat with you on the phone about it. I spent 8 years being very active in the Twin Cessna world, mostly when we had the 310 but also the 414.

pmiracing said:
Right now the budget doesn't allow for a turboprop.
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Certainly understand that. That's why we operated a 414 for 2 years. The only reason we have the MU-2 now was because of some fortuitous circumstances.
 
Ted DuPuis said:
The 414 and the 421 are the same cabin. The primary difference is the 414 has direct drive TSIO-520s while the 421 has geared GTSIO-520s. The 421 got the straight wing (going from tip tanks) sooner in 1975 or 1976 (I forget which) when the 421C was introduced. The 414A went to the straight wing in 1978. Note the 421B and C both have the longer nose (which is good for more baggage space), but the 414 only got the longer nose with the A model. You need a RAM VI or RAM VII 414 (tip tank or A model) to get the same useful load as an equivalent 421.

We had a 1977 414 for 2 years. I specifically wanted a tip tank model with the short nose for a few reasons. First that's what would fit in my hangar (the 421B is much longer, and the 421C/414A have a much wider wingspan). Second I did not want the geared engines - they are higher maintenance and more prone to case cracking. There is debate about this on the Twin Cessna forum, but pretty much 421 owners (who've typically experienced case cracking themselves but ignore it) are the only ones who defend the engines. The engines are very smooth and very quiet, and you do get better performance. Third, I didn't want the straight wing as they do tend to have some extra maintenance issues, specifically regarding corrosion under the boots. The tip tank fuel system is a bit more complex but it's not inherently difficult to operate.

A 421B is the best purchase price value on the market if you can find a good one, but you may pay for it later with engine maintenance.

If you'd like to discuss I'd be glad to chat with you on the phone about it. I spent 8 years being very active in the Twin Cessna world, mostly when we had the 310 but also the 414.



Certainly understand that. That's why we operated a 414 for 2 years. The only reason we have the MU-2 now was because of some fortuitous circumstances.
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The 414 usually has a different cabin layout, so i thought it was different/smaller. We definitely need the useful load of the 421 or 414 ram. There are a few low to mid time 421's out there right now with nice panels for a good price(around $150,000), 414 ram's are a little tougher to find. We do travel the Bahamas once a year so takeoff/landing distance is also a factor. We could get our Navajo in and out of 3000ft. comfortably. The cessna's look to be a little faster with less fuel burn than our pa-31p so that is also a plus. I would love to talk to you and get some more info.
 
Lots of twin-talk lately. These planes are just so badass, shame they're such a rarity now in terms of use. Are there any cabin-class *piston* twins still under production? Tecnam P2006 maybe?
 
Tantalum said:
Doesn't really count as "cabin class" but the DA62 is pretty sweet.. the gph is downright epic and you get turbo Cirrus speeds
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I mean, it has a cabin.
 
I've started flying a 421C a bit lately, and the one thing that always surprises me is the quiet engines. Cruise is at 1800 rpm (prop rpm, not engine), so it really makes a huge difference. The power reduction after takeoff is startling, to say the least, because it gets really quiet.
 
AA5Bman said:
Lots of twin-talk lately. These planes are just so badass, shame they're such a rarity now in terms of use. Are there any cabin-class *piston* twins still under production? Tecnam P2006 maybe?
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You could call the Tecnams cabin class, but they really don't fit nor are they aimed at the use cases of the piston cabin class twins or yore.

The issue is that if you can afford to spend the money on a new one, you want turboprops. A new 421 would be a $2M airplane (look at the cost of a new Baron for comparison). Nobody would spend $2M for a new 421. They primarily have a place in the market for people who either do shorter hops where a turboprop doesn't make sense, or for whom the purchase price of a turboprop is high enough (and the potential engine costs are scary enough) that it makes sense. The thing is they don't make brand new 40 year old planes, so it's a finite supply.
 
pmiracing said:
I have looked at some Aerostar's online, but they look pretty small in the cabin. Also I believe usefull load is pretty low?
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I had just under 1200lbs of useful with full fuel including the aux tank for 225 gallons.
At full full, I could go 1000nm at 260 KTAS in go fast mode.

Cabin is smaller than the big Cessna twins; however the tube is straight which actually gives more room in the back than most think.
The plane technically seats six, most actually have one or two of the middle captains chairs removed to seat four/five very comfortably.
Mine was setup for five, and I carried bunch of big guys on multiple occasions without issue.
Where some passengers will say it feels smaller is because the windows are lower and not eye level.

You really should get a flight in one before you decide :D

Tim
 
tspear said:
I had just under 1200lbs of useful with full fuel including the aux tank for 225 gallons.
At full full, I could go 1000nm at 260 KTAS in go fast mode.
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@pmiracing I'm good for $20 if you need someone to go in on this with you
 
kgruber said:
If you could afford the upkeep on a P-Navajo, you can EASILY afford a King Air!
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Everyone is scared of a p Navajo but no one knows what they are talking about. IF things break they are hard to find but it was a reliable plane for us up until a mechanic didn't complete his work. If you know how to treat an engine they are a good engine. I hear talk about how quiet a 421 is at 1800 rpm I'm sure a pa-31p is even quieter at 1600 rpm cruise. We purchased the p Navajo from a friend who has over 800 hours in it with little issues.
 
tspear said:
I had just under 1200lbs of useful with full fuel including the aux tank for 225 gallons.
At full full, I could go 1000nm at 260 KTAS in go fast mode.

Cabin is smaller than the big Cessna twins; however the tube is straight which actually gives more room in the back than most think.
The plane technically seats six, most actually have one or two of the middle captains chairs removed to seat four/five very comfortably.
Mine was setup for five, and I carried bunch of big guys on multiple occasions without issue.
Where some passengers will say it feels smaller is because the windows are lower and not eye level.

You really should get a flight in one before you decide :D

Tim
Click to expand...
I haven't seen one with a potty seat, so that may be a no go with the wife and kids. I am good for 5-6 hours but my crew is only good for about 2-3. I would love to take a look at one up close, anyone have one near MN?
 
pmiracing said:
I haven't seen one with a potty seat, so that may be a no go with the wife and kids. I am good for 5-6 hours but my crew is only good for about 2-3. I would love to take a look at one up close, anyone have one near MN?
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Ask over on www.aerostar-forum.com
You can also call the Aerostar factory and talk to them. When I was looking I flew out to the factory for my second demo flight in one.
It was good to get a tour on the plane, how it will be supported....

Tim

Sent from my SM-J737T using Tapatalk
 
Ted DuPuis said:
You could call the Tecnams cabin class, but they really don't fit nor are they aimed at the use cases of the piston cabin class twins or yore...
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The Tecnam 2006 is a trainer for all practical purposes. Maybe he was thinking about the P2012?

There's a real market that has developed with owners putting money into Cessna 340s, 414s and 421s. Major refurbishments. There's just nothing available today that fills that niche, and one can build a nicely appointed, modern avionics, pressurized airplane with a decent cabin for half the price of a good used Piper Meridian.
 
GRG55 said:
The Tecnam 2006 is a trainer for all practical purposes. Maybe he was thinking about the P2012?

There's a real market that has developed with owners putting money into Cessna 340s, 414s and 421s. Major refurbishments. There's just nothing available today that fills that niche, and one can build a nicely appointed, modern avionics, pressurized airplane with a decent cabin for half the price of a good used Piper Meridian.
Click to expand...

Back in 2014 I posted a thread about a 421C that was for sale. It had new factory remans with less than 100 hours, literally $75-$85K of avionics upgrades that were about a year old, new P&I, and the asking price was less than $375K IIRC.

It was a beautiful airplane, I guessed that perhaps it was a distress sale, because someone had spent a lot of money on it. User @N747JB, a former 421 owner, commented favorably about its attributes and price.

https://www.pilotsofamerica.com/community/threads/question-about-gtsio-520-hours-elapsed-time.72008/
 
All I can say is that IF they fit your mission, the cabin class pressurized twin Cessnas are great airplanes. Yes, they require maintenance. Yes, they burn more fuel than a Mooney. In spite of that, I really like mine.
 
pmiracing said:
I haven't seen one with a potty seat, so that may be a no go with the wife and kids. I am good for 5-6 hours but my crew is only good for about 2-3. I would love to take a look at one up close, anyone have one near MN?
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Every 414A/421 that I have seen has a potty seat, with a relief tube built into the cabinet. It may be bucket, not a flushing toilet, but it's a place to pee. :)
 
Coincidentally, I just flew with a client yesterday on a 2.5 hour each-way flight in a 340 (Ram VI conversion). Destination was 7500+ MSL, density altitude 9500 or so.

5 adults on board (us and 3 passengers).

Got up to FL230 for some weather, TAS was 207. Not as quiet as the 421 I previously mentioned (due to higher prop RPM since no geared engines) but not too bad either.

A very useful and capable airplane.
 
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N747JB said:
Every 414A/421 that I have seen has a potty seat, with a relief tube built into the cabinet. It may be bucket, not a flushing toilet, but it's a place to pee. :)
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I will say the relief tube is one of the things I really miss about the 414. The other one is the more spacious cockpit than the MU-2. But, Gatorade bottles work.
 
Ted DuPuis said:
I will say the relief tube is one of the things I really miss about the 414. The other one is the more spacious cockpit than the MU-2. But, Gatorade bottles work.
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I suppose it would be very bad to work a relief tube in a pressure vessel
 
MIFlyer said:
I suppose it would be very bad to work a relief tube in a pressure vessel
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Actually it's a lot easier. You put a fitting through the pressure vessel, and since the plane is pressurized it automatically has airflow to force the liquid out of the plane. In the Navajo they needed to have a venturi for it since that was unpressurized and you had to create a suction to ensure the liquids went out. If you look under a Navajo with a relief tube you can see the venturi. On the 414 it was just a little tube sticking out angled aft.

Relief tubes in pressurized planes just have a little lever you push to open the plug. On the 414 this was plugged up after years of disuse, so I soaked the mechanism in vinegar for a few days and it freed right up. This was identical to the Cheyenne.
 
Ted DuPuis said:
Actually it's a lot easier. You put a fitting through the pressure vessel, and since the plane is pressurized it automatically has airflow to force the liquid out of the plane. In the Navajo they needed to have a venturi for it since that was unpressurized and you had to create a suction to ensure the liquids went out. If you look under a Navajo with a relief tube you can see the venturi. On the 414 it was just a little tube sticking out angled aft.

Relief tubes in pressurized planes just have a little lever you push to open the plug. On the 414 this was plugged up after years of disuse, so I soaked the mechanism in vinegar for a few days and it freed right up. This was identical to the Cheyenne.
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wow! I had no idea you could actually have a relief tube in a pressurized aircraft. cool
 
MIFlyer said:
wow! I had no idea you could actually have a relief tube in a pressurized aircraft. cool
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All pressure vessels have holes in them. The unintentional ones we call "leaks." :)

When you fly a pressurized aircraft you can pretty easily find out which vents are the air coming from the pressurization source (whether it's bleed air off the turbos or off of the compressor). Most pressurized aircraft then have an outflow valve and a pressure relief valve on them (sometimes given different names). The outflow valve serves the purpose of regulating the cabin altitude and pressure by leaking the air out of the cabin at an appropriate rate to maintain a cabin altitude and a cabin vertical speed, as well as respecting the maximum cabin pressure differential. The relief valve is a backup to prevent the cabin from overpressurizing. And then you also have the ability to turn off the bleed air flow and then there's also a manual pressure dump as well (at least on the 414 and MU-2).

On the MU-2 when you turn off pressurization from a given engine it literally shuts the valve for bleed air at the engine. This means more air from the compressor goes through the hot section, meaning that you don't temp out as quickly. Therefore you can potentially make more power at takeoff and hold it to a higher altitude. That's why for takeoff turning off the bleed air is part of the checklist. I'll turn it on once gear is up and climb is established unless it's a high DA environment, in which case I'll hold a bit longer.
 
I had a 414A for about 15months. Only thing I miss is the wide cabin. I got tired of scrubbing flights for mx issues. Never trusted that damn thing. Ran a lot of numbers looking at alternatives. Now I fly a Super Cheyenne (Cheyenne I with -135a upgrade) and I could not be happier. Trouble-free. Best kept secret in aviation. Mx friendly for the owner-pilot, as mx is hourly-based rather than calendar-based in the King Air. Only good thing about the 414 is that it gave me ME hours, so insurance in the Cheyenne was a slam dunk (I have a commercial MEL which probably helped.)
 
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