Which Twin?

[Foxy2004]

Looking to buy/group share a Twin to fly airways, so need de-iced, but not turbo. What aircraft do you recommend, trying to keep the cost down to sensible levels?

[Chuck Ellsworth]

I would suggest a good Beech 18.

Chuck E.

[Chilli Monster]

Aztec E or a non-turbo'd F

Why non-turbo?

[Foxy2004]

Non-turbo just to keep costs down.....

[vanhigher]

if you want to keep costs down ..... buy a single ;)

[eyeinthesky]

It depends how much you want to carry. If you are mainly 2/3 up then you could do worse than a BE76 with TKS deicing. Only 4 seats, but cruises at 140 IAS and will be OK up to FL90 or FL100.

Beyond that, a non-turbo Seneca will give you six seats but you have to choose between filling them or the tanks.

If you regularly want to fly with 5 or more, then the Aztruck is a good load carrier but attracts Euronav charges because of its weight.

[bookworm]

As eyeinthesky says, it depends on why you're looking at twins. If you want to regularly haul 4+ people, you may want to think bigger. If you just want the security of a second engine for you and one or sometimes two passengers, a smaller twin will work out much cheaper.

I think it's hard to beat the Twin Comanche. With two 160 hp engines and a MTOW under 2 tons, it's a 150 KTAS cruiser in airways on 13 USG/hr avoiding nav charges. But the aircraft is necessarily old (production ceased more than 30 years ago). Its successors, the Seminole and to an extent the Seneca, don't have all of the advantages.

[IO540]

Can anyone explain why there haven't been any new twins coming on the market for about 30 years?

Apart from the DA42, and that one is a very untested proposition at present.

[Chilli Monster]

Two words - product liability

Both Piper and Cessna were hit by punitive lawsuits back in the 80's / early 90's due to people killing themselves in their aircraft and, notwithstanding it was pilot error, the 'sue for anything' culture that was (is) prevalent signed their deathknell. Piper went under (that's why they're called the 'New' Piper Aircraft Company) and Cessna came close.

When the risk was removed by a change in U.S legislation the damage had been done and there was no money left in the pot for all new designs - just modernising the old ones as the industry is still recovering.

[Foxy2004]

Which twins up under 2 tonnes? The twin commanche, Duchess and Seneca I, but what others?

[englishal]

I would opt for a Seneca II over all of the above (except maybe the Aztec), even though it does have turbos (which is not a bad thing at all).

4 blokes, full fuel no problem. SE ceiling of 13,000' and ceiling of 25,000'. De-icing available as is oxygen to get you above that icing.

Good condition ones are available at around $100,000 - $140,000 and they don't attract airways charges....

Not keen on the Seneca I, the Seminole is just a twin archer suitable for training but not sure I'd buy one (In my view of course), as is the BE76.....

[formationfoto]

Having experienced Seneca II, Cessna 310, and more recently Aztec 'C' I would suggest for most uses Seneca II. It flies nicely, avoids Euronav, and is legally a reasonable load carrier. The 310 is a bigger looking machine and feels more like a grown up aircrfat than the Seneca which feels like a PA28 with two engines. As for the Aztec. Will carry antyhing. Is a big, thirsty, lumbering machine, robust and cheap to buy (but expensive to run).

In order Seneca II, Aztec, 310. Can't really comment on other twins at the low end other thant the tein comme which was my first owned twin. Loved it, great little machine but getting expensive to operate now because of age.

[slim_slag]

Agree with vanhigher, what reasons do you have for eliminating a single?

[nasib]

Seneca II's are over 2,000Kg and would therefore incur Eurocontrol charges if flown IFR. To avoid such charges the aircraft would have to be re-certified 1,999Kg with the resultant loss of useful load.

Nasib

[andrewc]

You might like to think about a Cirrus SR-22,

-- Andrew

[Foxy2004]

Slim_Slag

A twin because I want to use my new IR and prefer 2 donkeys in poor weather and over water.

Looks like a Seneca II is getting the popular vote, but had thought it under 2 tonnes, so that's a blow.

[bookworm]

As nasib says, you can make a Seneca II under 2 tons by registering at 1999 kg, and you'll find many if not most on the UK register are 1999 kg. You lose about 170 lb from the useful load by doing so.

[Chilli Monster]

Most UK registered Seneca II's are certificated at 1999kg, so don't despair just yet. Provided you haven't got the one with the long range tanks then 4 up plus full fuel is almost possible. Even with the long range tanks there's normally not a problem.

However - with lots of fuel and only two in the front you're W&B is seriously out, so needs careful consideration.

Drop me a PM if you want to discuss further (all my Seneca flying has been in the II)

[slim_slag]

Foxy2004,

.....and prefer 2 donkeys in poor weather and over water.

Me too, especially ETOPS certified as they have lots of lovely redundancies and other risk-reducing procedures and safeguards. Also means I can sit in the back and drink cocktails and let somebody else worry about the weather! In poor weather I take the airlines nowadays, especially if the alternate is a piston twin with one of the selection criteria being cheap! I Hope you find what you are looking for, I long ago gave up on relying on light piston planes for reliable transport when there is any weather around...

[englishal]

However - with lots of fuel and only two in the front you're W&B is seriously out, so needs careful consideration.
What do they do to register it for 1999KG? Do they actually do anything, or is it a paperwork exercise? If a paperwork exercise then surely the W&B will remain the W&B designed for the aircraft by Piper (i.e. it'll behave the same as a Seneca II in the USA).....just you might be overweight on paper?.....if you see what I mean ;)

[eyeinthesky]

Two things:

1) Another twin under 2000kg is the GA7 Cougar, but in my experience its performance is worse than the BE76.

2)
QUOTE
What do they do to register it for 1999kg? Do they actually do anything, or is it a paperwork exercise? If a paperwork exercise then surely the W&B will remain the W&B designed for the aircraft by Piper (i.e. it'll behave the same as a Seneca II in the USA).....just you might be overweight on paper?.....if you see what I mean
UNQUOTE
Yes and no. If the aircraft is built for a weight over 2000kg then of course it can physically carry it. But you cannot prove this capability on paper as the C of G envelope will only go up to 1999kg MTOW. If you load it over that and anything happens, you invalidate the insurance. You decide on whether the risk is worth it.

You also need to decide how often you will fly airways with it compared with how often you will need the MTOW to be over 1999kg. If one is greater than the other then you need to balance the relative costs.

The 'two up, full fuel' scenario is a feature of the aircraft and is not simply a paperwork exercise. It is to do with balance, not weight. Too much weight on one end of the seesaw makes it an unworkable game!

[Chilli Monster]

EA - just to expand.

I once turned up for a test in a Seneca II fitted with long range tanks. I walked away and re-booked.

Why?

The refuellers had helpfully fuelled the aircraft to the brim. We were 100kg below MTOW at 1999kg. However, on the weight and balance calculation the weight was so far forward of limits that had we had an engine failure we were going rapidly down nose first.

Yes - the certification is purely a paperwork exercise, with the aircraft placarded as such and any W&B graphs stopping at the weight, rather than extending onwards like those in U.S POH's. However - balance is another matter and needs seriously thinking about if you start putting more than 140 litres of fuel (3.5 hours) a side on board.

[formationfoto]

Good warning about the W+B. It is extremely easy to get a Seneca II to a forward C of G out of envelope position without pax in the back. I believe it requires an awful lot of pulling on the yoke at just the right time to flare nicely (not that I have ever flown one in such a condition).

I also understand that they fly well with full fuel, full seats, and baggage but that would, of course place them over weight and would invaildate insurance etc.

Mine was a 1999kg certified machine and of course refused to fly the moment an additional weight was placed in it. Clever machines these aircraft that can read certification schedules.

[Timothy]

Having operated an Aztec E for about eight years, I cannot praise it highly enough. It is enormously stable, solid and reliable, can be operated out of minimal runways (I accept 470m hard, 700m grass) is a fabulous load lifter - I have done a practice EFATO with 5 rugby players and full fuel and (admittedly on a cool day) it went up like a rocket.

The difference between an Aztec and a Seneca is that between wood and tin, or between a Merc and a Skoda. Nothing you can really measure, just the feeling of solidity and avuncular reliability.

It is true that Aztecs are very cheap. However, maintenance need not be too bad...Singh at Biggin knows them well and always seems to be able to source spares...and fuel burn is in the normal range, 100l/hr gives me 165kt TAS, or I can go slower for less.

The Aztec is a compromise between a Maule and a C421, but, to my mind, has the balance of the best of both worlds. Irv Lee wrote a good review about six or eight months ago in Flyer.

I would say that, in order of preference, the models are E, F, D, C. If you do get an F, look for long range tanks and the second hydraulic pump. If you do get the LRT option, remember that it limits your payload.

[Chilli Monster]

As 'F's have two hyd pumps and 'E's only one I'm intrigued as to why you put the E first? That and engine output (aren't 'E's 235 verses the 'F's 250?)

[Chimbu chuckles]

Chilli monster...rather than walking away and rebooking why didn't you put 100kg of ballast as far aft as possible/necesary?

[Chilli Monster]

Chimbu

1) It wasn't available

2) The CofG was so far forward that the 100Kg would have had to have gone in the tailcone! (Believe me - I went through all the possible options - and slimfast aint that fast ;) ).

[Timothy]

As 'F's have two hyd pumps and 'E's only one I'm intrigued as to why you put the E first? That and engine output (aren't 'E's 235 verses the 'F's 250?)
Not all Fs have the extra pump, just as they are not all turbos and don't all have the extra tanks.

Es have the 250 engines, as do the Ds.

Es are faster than non-turbo Fs, by a fair margin (as much as 10kts). I don't know why, but probably the tailplane design.

[Dude~]

I'm surprised nobody has yet mentioned the Partenavia P68B, although they are not very common.

I flew one in Oz a while back, lovely plane with a nice cockpit which you have to enter from between the pilot seats having entered the plane through the door at the back which makes it feel big and 'airline' like!

Comes with 2x200hp lycoming IO-360s, basically arrow engines, 6 seats, 140kt cruise, fixed gear solid enough for rough strips, good payload, but watch W&B when solo.

Also comes with 330hp turboprops!!

I think there is one at Elstree for hire, and a syndicate running a nice model at Denham.

For picture see

http://www.airliners.net/open.file/570966/M/

[Timothy]

...and when you fly into icing the engines stop.

[surely not]

What about a nice DH86 or DH89? :D

[Dude~]

Timothy,

I thought most light twins weren't cleared for flight into known icing anyway, so wouldn't surprise me if the engines stopped in icing conditions. Does the P68B have a particular problem with icing?

[Chilli Monster]

What about a nice DH86 or DH89?
Rather have a DH98 :) (Ah...........De Havilland!)
I thought most light twins weren't cleared for flight into known icing anyway,
So why do you think most have have heated props, de-icing boots, full IFR kit (mostly).

Both the Seneca and Aztec POH's I have say cleared for flight in known icing (you just try not to stay in it too long).

[Timothy]

As Chilli says you can fly de-iced twins into known icing and the Aztec is pretty resilient (I have had some hairy moments in C404s and PA31s, though.)

Partenavias have a particular problem with ram ice in the engine air intakes. Both engines stop. So I suppose technically it is no longer a twin, but a glider and therefore belongs no longer in this thread :p

[rustle]

My understanding, and please correct me if I am mistaken, was that the main reason Partenavias struggled with ice was more to do with the non-retractable gear collecting vast quantities of ice - so much so that even with deiced wings/props the weight alone could cause you problems.

The ice-in-air-intakes being dealt with by the revised "alternate" air intakes of the later models - like the one we took to Jersey :8

[LowNSlow]

What about a Cessna 337? Does away with all those potentially nasty asymetric problems. Is a tad noisy (!) and not allowed in some airfields becasue of the din. I've always wanted one though.

I liked the Twin Comm and the Beech Duchess. Not sure if they have the performance you want though.

[Timothy]

Rustle, AFAIR we flew to Jersey in CAVOK, so weren't able to test proclivity to crash in icing. There have been a number of Partenavia + ice crashes, I am sure from a variety of causes, but the air intakes is one most cited. Do late models have automatic alternate air?

LowNSlow, the push-me-pull-you design brings it's own dangers, because it is very difficult to recognise a rear engine failure, which has led people to stall.

[rustle]

Rustle, AFAIR we flew to Jersey in CAVOK.

Outbound:
EGHH OVC @ 1200
EGJJ BKN @ 100,
FZ @ 8000ish
FPL @ FL60

Inbound:
EGJJ CAVOK
EGHH OVC 600
FZ @ 6000
FPL 3000

:8 :8


Nowhere near icing though, agreed. :)

[LowNSlow]

Timothy I appreciate that it has it's own problems to compensate for the lack of asymetry (sp?). As I understand it the major problem was unrecognised lack of power from the rear engine on takeoff. This was compensated for by powering up the rear engine first. I've been told that you rapidly realise if the rear engine goes down in flight due to the large reduction in noise (ANR headsets could disguise this though)! Still think they look lovely. Ah, if only I had the cash..........

[LowNSlow]

Foxy2004 there is a lovely Twin Commanche for sale on ebay. If I only had £30k burning a hole in my back pocket......

[surely not]

or perhaps a Miles Gemini, or a DH Dove, or a Beagle 206. So much nicer than the American solutions :)

[S-Works]

The BE76 Duchess is my preffered weapon of choice. I fly it around 150hrs a year and she is gracefull lady if a little slow compared to other twins.

I dislike intensly flying the Sennecca and avoid it unless there is no other option! The one I have access to is a Sennecca 201 Turbo, it goes OK but is very heavy in pitch.

The twin commanche is lovely to fly but a bit long in the tooth. The 310Q was also nice to fly.

The weirdest I have flown was the Aerostar, very twitchy and cramped, like a 6 seater 152!

[IO540]

I don't think anyone has answered my question on why no new twin designs have come to the market for such a long time. The liability issue can't be extra bad on twins over singles.

Is it because high perf singles come so close to the perf of a twin that most people buy a single, and only a small % of buyers are willing to pay the substantial premium (fuel and maintenance especially) for the engine and systems redundancy? And those buyers are happy to just keep maintaining an older aircraft?

Having said that, there are very few "new" 150kt+ single designs...

[slim_slag]

IO540,

Maybe this oft-cited article by Mike Busch (http://www.avweb.com/news/usedacft/182809-1.html) gives an idea as to why twins are not so popular, resale prices of light twins vs decent singles also give an idea of the demand.