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New License, buy a retractable?

Sorry, what is DOC?

DOC = Direct Operating Cost. Usually refers to fuel, oil and other consumables (plus route charges, if applicable) on a per-hour basis.

Last Edited by 172driver at 03 Aug 18:57

There was some discussion here about the speed merits of retractable gear. This video is really interesting:



He goes into depth on the numbers of a range of different SEPs. Perhaps unsurprisingly the Panthera appears to be hugely efficient.

United Kingdom

Any thoughts from you guys? :)

As @boscomantico said, Jan Brill of Pilot und Flugzeug is the guy who knows all there is to know about the PA30 series. Not least due to him and his predecessor who also operated one for a while, the Twin Comanche is my persona dream plane, to be exact the Turbo version and if possible one with boots.

Jan also published a lovely write up on the PA30. Maybe @boscomantico can provide the link as I only have my phone.

But also normal Twinkies are lovely and yes the DOC is not that far from a large SEP. If I had the possibility, that is what I would do, provided however that

- you want to get involved in maintenance. This is an old airplane and if you don’t want to know its details, stay away.
- you have time to become proficient and are willing to do recurrence training regularly. Twins tend to bite the untrained.

Other than that by all.means go for it.

LSZH, Switzerland

Mooney_Driver wrote:

- you want to get involved in maintenance. This is an old airplane and if you don’t want to know its details, stay away.
- you have time to become proficient and are willing to do recurrence training regularly. Twins tend to bite the untrained.

Yesterday I was about to write the same, but on the second thought both is not true for the TwinCo. The 160hp engines are dead simple, widely used among singles, and as far as I’ve heard don’t come expensive if maintenance is done by mechanics. The one I was about to buy is maintained 100% not by the owner. And the other thing is, that as far as what I’ve seen the TwinCo is not that difficult to handle. It has a bad reputation from back in the 60ies when it had been widely used as a trainer and training syllabus was different. But as soon as safe speed is obtained it seems to be quite easy.

I know several guys who operate a Twin and all tell me that it’s a dream. All, however, have quite some experience with aircraft ownership, I have to say.

I wouldn’t buy a Twin as a first aircraft, if not having unlimited funds and a lot of time for training.

Germany

The counter rotating prop Twinkie is much less likely to bite the untrained.
You can do much of the recurrency training sitting on your kitchen chair and running through the procedures over and over, if you can’t get flying
The other thing to do is plan virtual flights where you keep asking the question,“what happens if”.
With the Twinkie you have options that you sometimes don’t have with a single.
Insurance companies penalise twins until the pilot has more than 100 hrs PIC. After that it can reduce dramatically.
Your hull insurance will be nowhere near that of a modern high performance single and about that of a complex SEP of similar era, maybe slightly lower.
DOC are around the same as most high powered singles of the same era and probably a little less than more modern types like the SR22 or Beech36. Possibly a little more than an Arrow, more than a Mooney M20J.
Maintenance wise, even if you get one with turbo engines, they don’t seem to suffer (according to the Twinkie Owners forum) any more engine problems than the non turbo versions
So as has already been pointed out you are doubling up on everything.
Maintenance of the boots doesn’t tend to be a very high maintenance problem.
If you are prepared to put in the hours yourself to do the things you are allowed to do and if you have a friendly maintenance outfit or a freelance Part 66 engineer, it is surprising how you can reduce the costs to very near those of the single Commanche with its much large engine
Performance wise there’s not a great deal of difference, except that the turbo twinkie will get higher faster. Are deicing boots available for the single Commanche?
With Vortex Generators the Twinkie is a good short field performer.
The problem is that in the last year or so people seem to have seen the value of these aircraft and prices have been steadily rising.
Part of this could be that existing owners love their Twinkies so much they make sure that the maintenance is always spot on, they have lavished options on them and many come superbly equipped with the most up to date avionics set up.
But in comparison with SEPs which often tend to be a little more expensive for the same equipment, IMO they are still good value for anyone who wants to own an aircraft for touring and to hang onto it for some years.
I don’t understand the not running LOP remark.

France

I helped a PPL convert onto a nice PA-30, a good, comfortable MEP. The overhaul cost on the CR engines are high, and while the CR concept has worked well on the Seneca and Navajo (bigger rudder and longer moment), not sure how discernible the effect is on the PA-39. Recall the PA-30 Vmc history resulted in the FAA introducing Vsse which is particularly high for the PA-30.

Long story short the owner eventually sold the PA-30, and switched to a Saratoga. I believe he found the maintenance and the need for an annual revalidation sent him back to an SEP.

Oxford (EGTK)

gallois wrote:

Performance wise there’s not a great deal of difference, except that the turbo twinkie will get higher faster. Are deicing boots available for the single Commanche?

Just to have that clear: The Turbo Twin climbs faster than the non-Turbo Twin, but the Single is able to climb faster than the Twin.

I’ve seen singles with deicing boots, but they’re not so common as e.g. in the Twins.

gallois wrote:

I don’t understand the not running LOP remark.

This is from hangar talk. I know of several Twin owners who tried to run it LOP but it’s unwilling, even with equalized injectors. It’s running rough. The IO-540 in the Comanche single in turn runs fine LOP.

Germany

The turbo climbs faster above 7000ft.The single Commanche with the 260 IO540 C and the Rajay turbocharger climbs better than the twin from around 10,000ft, from 7000 to 10000 there doesn’t seem to be much difference and up to 7000 ft (approx) the single Commanche seems to have a slight edge. It’s a long while ago when I got into Twinkies so I don’t remember all the exact figures, but I remember doing the comparisons in around 1997.
The problem is that no 2 Twinkies or PA24 Commanches seem to be the same these days, all have been owner modified as options became available. There is a guy with a Twinkie here and he reckons his Twin Com outperforms any of the singles in all departments. I don’t argue he’s got one I haven’t.

France

gallois wrote:

There is a guy with a Twinkie here and he reckons his Twin Com outperforms any of the singles in all departments

I have only flown a Twinkie, but around ten years ago a beautiful Comanche 180 went up for sale in the UK. It was in immaculate condition with an original, but new paint scheme. In those days it sold for around £20K. Alas I can’t find it on the G-register.

Having operated an MEP if you are not planning regular over water or night cross country flying (100 hours plus p.a.), you will not maintain good currency and it is not worth the expense.

Oxford (EGTK)

gallois wrote:

he reckons his Twin Com outperforms any of the singles in all departments

Book value states differently. But the discussion here doesn’t lead nowhere. Let’s agree on that they’re close enough to each other that they’re just comparable. Anyways, there are hundreds of Turbo Twins but practically no Turbo Single available. So from this point of view, it’s pointless to promote the Single.

The Comanches went up in pricing. The 180 Comanche is a nice tool, and outperforms the typical SEPs like Arrow or 172RG. It’s in the same class, so if not payload, performance and seats of a 260 or Twin are required then it’s ok and much cheaper in lots of ways. However, the 180 may even be from the 1950ies…? There are a lot of things to look after on such an old plane. On the other hand, they are very well designed and crafted. No problem to use it another 50 years.

Germany
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