Twin engine input

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ShawnR
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Twin engine input

Post by ShawnR »

What is the general opinion of late 60's Twin Commanche aircraft? From my research, it seems there were some concerns about the non counter rotating engines. Is that fact or fallacy? I have no twin engine experience but the price of them is appealing. I have always owned the aircraft I am training in so wondered if buying one for my multi IFR rating would be a big mistake... And then what to do with it later.... If the characteristics of the design make it a poor sell, then I need to either work it or use it...and I don't think my wife would be anymore interested in getting into a small twin than she is getting into a small single. So that leaves work for it. Has anyone flown one for a job? Is it that dangerous to use in an Air Taxi operation versus a design with counter rotating engines? I owned a Tomahawk. I researched it before I bought it. I found those that had negative opinions had never flown one. Those that had actually owned and flown it, loved it. I bought it, and loved it..as much as one can love a tiny airplane...:-)

So, I am hoping for input from those with PA30B experience.

Thanks
Regards,
Shawn
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photofly
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Re: Twin engine input

Post by photofly »

In general the purchase price is cheap - sometimes you can find old piston twins given away nearly free. But the maintenance and running costs can be extreme.

Counter-rotating engines: most twins have engines that rotate the same way: two of the same engine is usually preferred for maintenance/parts reasons.
Is it that dangerous to use in an Air Taxi operation
It's not entirely clear from your post, but if you are thinking about setting up an Air Taxi operation and you don't have a multi-engine rating yet, it's going to be a *long* time before you you will be acceptable to (or as) the chief pilot of an approved operator. Setting up a commercial operator has costs and difficulties way way way beyond the value of simply finding something to do with an airplane you happen to own. For a start: maintaining a light twin on a commercial maintenance schedule will cost 3-5 times as much as you would need to pay to maintain the same airplane under private registration.
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JAHinYYC
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Re: Twin engine input

Post by JAHinYYC »

I did my Multi and Multi IFR in a PA30B thirty years ago and owned one for three years up to 2018.

I loved, love, loved the airplane and would have kept it if I had not decided to sell my GA aircraft. (I got a job flying full time in 705).

I would be happy to share my experiences.
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PilotDAR
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Re: Twin engine input

Post by PilotDAR »

I quite liked the PA-30, very nice to fly, and in my opinion not the devil it is reputed to be on one engine. I did lots of single engine work, including stalls (I was flight testing for a prop change approval). It behaved politely for me all the time. I did find that it demanded being landed with the nose held light, it tended to wheelbarrow if allowed to, but that was my inexperience on type, it flew fine, once I disciplined myself.

Note that it has both a "Operator's Handbook" and an "FAA approved Flight Manual" and only the flight manual is an official document. I think that the operator's handbook was written by the marketing department, as it contained very optimistic performance information - which the FAA had not approved!

All that said, the older the plane, coupled with more complexity, will drive costs way up, and with increasing attention to aging aircraft issues, new concerns could be found. Set aside a reserve for unexpected costs.
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valleyboy
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Re: Twin engine input

Post by valleyboy »

One of the nicest and least expensive to operate was the beech travel air. Beech craft strong and using about 10 igph total. Reasonable single engine performance but still like every other light piston twin, heavy will negate that. The aircraft has reasonable speed and range, my recollection is about 6 hours and 160 kts. I always thought that is what I would buy if I was looking for a light twin.

If you google the aircraft for sale you will notice a large variation in price. Like any other used aircraft you must investigate and likely money well spent to have an AME inspect the aircraft and books.

These aircraft were used as multi IFR trainers for years. That in its self is a statement for the durability and reliability of the aircraft. I have flown both the Baron and the Travel Air and while the Baron was nice it was far more expensive to run and only about 15 kts faster.

As for counter rotating engines they are a money pit and not really worth the investment and the difference in performance isn't worth the added expense.
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ShawnR
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Re: Twin engine input

Post by ShawnR »

photofly wrote: Tue Sep 22, 2020 3:55 am In general the purchase price is cheap - sometimes you can find old piston twins given away nearly free. But the maintenance and running costs can be extreme.

Counter-rotating engines: most twins have engines that rotate the same way: two of the same engine is usually preferred for maintenance/parts reasons.
Is it that dangerous to use in an Air Taxi operation
It's not entirely clear from your post, but if you are thinking about setting up an Air Taxi operation and you don't have a multi-engine rating yet, it's going to be a *long* time before you you will be acceptable to (or as) the chief pilot of an approved operator. Setting up a commercial operator has costs and difficulties way way way beyond the value of simply finding something to do with an airplane you happen to own. For a start: maintaining a light twin on a commercial maintenance schedule will cost 3-5 times as much as you would need to pay to maintain the same airplane under private registration.
Thanks Photofly. Having just finished a CPL, wondering what to do next. A 703 operation kinda sounded ok...but then more research is showing me it might be a bit out of my league, given my experience. You are correct. I was also wondering what the differences was from private to commercial for costs. If a reasonable business plan could be drawn up, I thought maybe a pilot with experience could be hired till the owner could be brought up to speed. But as you point out, maybe I will (meaning not maybe, I will...) focus on the ratings first. I am an old guy looking at options with a new CPL. Every new plane has been fun ( I have had a few) and a great learning experience.

Thanks
Cheers,
Shawn
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digits_
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Re: Twin engine input

Post by digits_ »

Where are you located?
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ShawnR
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Re: Twin engine input

Post by ShawnR »

digits_ wrote: Tue Sep 22, 2020 6:22 am Where are you located?
Thunder Bay
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ShawnR
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Re: Twin engine input

Post by ShawnR »

Sorry. Did not mean to ignore the other posts. Thanks for all of the input. It is much appreciated. My plan for the CPL was to try to get into a PC12 or Caravan. At my age, not about to start a new career, trying to climb to a major airline. I just want to fly for fun, hope to be an asset to some small company who does not need to worry about me moving on, and have someone else pay for fuel. :-) COVID of course put a dent into those plans, as far fetched as they might have been anyways. If I was to tell my wife I was to go to Timbuktu for a year of fun flying, I think the divorce would cost more than I would ever make....

The Multi rating looks like a fun rating. I will know more about the IFR as I continue to plug along with the online stuff, and then figure out where to get the air work done.

Thanks,
Cheers, Shawn
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co-joe
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Re: Twin engine input

Post by co-joe »

The weird thing that makes the counter rotating engines on a Twin Comanche desirable is that it's 20 kts faster than the normal one. (No idea why) There was a school in YQL that had one years ago. The whole no critical engine thing wasn't really that big of a deal. I think the Vmca is 3 kts lower in the one with counter rotating engines. If you go below Vmca on one engine it still becomes uncontrollable just like all twin engine aircraft.
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youhavecontrol
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Re: Twin engine input

Post by youhavecontrol »

co-joe wrote: Tue Sep 22, 2020 9:09 am The weird thing that makes the counter rotating engines on a Twin Comanche desirable is that it's 20 kts faster than the normal one. (No idea why)
I'd guess it's faster because the engine and thrust forces are balanced with counter-rotating engines, so there's no drag penalty caused by aerodynamic/trim inputs. I'd be interested to know if other aircraft have a significant difference in performance between critical engine and counter-rotating engine designs. 20 knots seems like a lot!
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photofly
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Re: Twin engine input

Post by photofly »

ShawnR wrote: Tue Sep 22, 2020 6:14 amI was also wondering what the differences was from private to commercial for costs.
Private maintenance: CAR625 Appendix B & C: inspection once a year with a local AME. Fix things as they break, but you get a lot of latitude since nobody is checking. Run the engines on condition for as long as you like (and you think they're safe). Change your own oil, tires, battery, filters.

Commercial maintenance: develop and produce an individual maintenance schedule for the aircraft, submit it to your principal maintenance inspector for approval, then follow the schedule which will include inspection intervals (likely 50, 100, 200 hours for the aircraft) plus other manufacturer recommendations for parts replacement (fuel hoses 10 years, seat belts 12 years, mags 500 hours) or overhaul (engines at TBO or 12 years). Defects have to be fixed within 72 hours or (if not an airworthiness matter) deferred for up to 30 days but after that the aircraft is grounded. You can't change your own oil, battery, tires or filters. All work has to be done by an approved AMO that works on your type. Google for "Small Operator Maintenance Control Manual" for more info.
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ShawnR
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Re: Twin engine input

Post by ShawnR »

Thanks photofly. I figured more strict of course, but that sounds intense. It was a fleeting thought to justify buying something bigger and "cooler" than a C172. I guess I will need to find another excuse.... :roll:
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photofly
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Re: Twin engine input

Post by photofly »

Would you want to put your children in a piston twin air taxi flown by a pilot who got their multi-engine rating last week, and whose engines are 500 hours past TBO, with seatbelts from the early 70s, and which was last inspected ten months ago?

I wouldn’t. And anyway, there’s not a lot of un-met demand for VFR air taxi flights. Check out standard 723 for the operational complexity you’re in for, especially for IFR approval.
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co-joe
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Re: Twin engine input

Post by co-joe »

youhavecontrol wrote: Wed Sep 23, 2020 12:12 pm
co-joe wrote: Tue Sep 22, 2020 9:09 am The weird thing that makes the counter rotating engines on a Twin Comanche desirable is that it's 20 kts faster than the normal one. (No idea why)
I'd guess it's faster because the engine and thrust forces are balanced with counter-rotating engines, so there's no drag penalty caused by aerodynamic/trim inputs. I'd be interested to know if other aircraft have a significant difference in performance between critical engine and counter-rotating engine designs. 20 knots seems like a lot!
The performace on that twin was unreal. I had done my training in a Grumman Cougar which had the exact same horses under the cowl, but this PA30 did 180 Kts! C-FBOZ is the ident, not sure if it's around any more. After the ride, the examiner (Scary Barry) complemented the owner on what a performer the aircraft was.

On one engine it was easy to handle, which is a double edged sword on an IFR ride, you're marked on your ability to hold airspeed so just because you’re climbing at 700'/min doesn't mean you passed if you're 20 kts fast. It had a Loran C, and a VOR RNAV which is a weird thing as well. Pre GPS RNAV.

In the end though having different part numbers from left to right engines would make maintenance more expensive.


Edit: I found a pic online of it parked at the muni in 2009 and looking at the right prop you can see it still spun the wrong way. https://www.jetphotos.com/photo/6615792
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ShawnR
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Re: Twin engine input

Post by ShawnR »

Dropping the Air Taxi idea...

If one was to consider buying one to get a multi rating IFR in, and then enjoy for a while, (personal use), what would a preferred model be? This will probably be answered by what one trained in...I suppose. I would think that, after only having flown several different ones, can one compare. But anyone have pros and cons on the ones you have been in? Sounds like the Commanche would be ok. Are they all about the same, give or take? ie Seminole vs Seneca? Cessna models vs Piper vs Beech? The info already mentioned in previous posts has been interesting. I am only just starting to look and not sure how serious I am. But it would be interesting to get input.

Thanks
Shawn
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praveen4143
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Re: Twin engine input

Post by praveen4143 »

Since you are closer to sea level for altitude, you wouldn't need anything turbocharged per se. Piper Seminoles seem to be the defacto choice for a lot of flight schools for ME training from what I have seen. Smaller engines that sip fuel more judiciously would seem to be the selling point I guess...
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((dB))
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Re: Twin engine input

Post by ((dB)) »

photofly wrote: Wed Sep 23, 2020 3:59 pm
Private maintenance: CAR625 Appendix B & C: inspection once a year with a local AME. Fix things as they break, but you get a lot of latitude since nobody is checking. Run the engines on condition for as long as you like (and you think they're safe). Change your own oil, tires, battery, filters.
I've been looking for a reference for this for a couple of months now, I've been asking questions wondering why it is allowed in the USA but not over here. Would you happen to know where I can find this please?
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praveen4143
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Re: Twin engine input

Post by praveen4143 »

((dB)) wrote: Thu Sep 24, 2020 7:01 pm
photofly wrote: Wed Sep 23, 2020 3:59 pm
Private maintenance: CAR625 Appendix B & C: inspection once a year with a local AME. Fix things as they break, but you get a lot of latitude since nobody is checking. Run the engines on condition for as long as you like (and you think they're safe). Change your own oil, tires, battery, filters.
I've been looking for a reference for this for a couple of months now, I've been asking questions wondering why it is allowed in the USA but not over here. Would you happen to know where I can find this please?
Are you looking for this?
https://tc.canada.ca/en/corporate-servi ... tions-cars
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((dB))
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Re: Twin engine input

Post by ((dB)) »

Exactly thanks Praveen4145
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