Which Twin?
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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!
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!
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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.
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.
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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.
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.
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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.
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.
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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
).
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
).
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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?)
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.
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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/
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/
Last edited by Dude~; 13th Nov 2004 at 22:52.
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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?
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?
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What about a nice DH86 or DH89?
(Ah...........De Havilland!)
I thought most light twins weren't cleared for flight into known icing anyway,
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).
Sub Judice Angel Lovegod
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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
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
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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
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
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.
I liked the Twin Comm and the Beech Duchess. Not sure if they have the performance you want though.
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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.
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.
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Rustle, AFAIR we flew to Jersey in CAVOK.
EGHH OVC @ 1200
EGJJ BKN @ 100,
FZ @ 8000ish
FPL @ FL60
Inbound:
EGJJ CAVOK
EGHH OVC 600
FZ @ 6000
FPL 3000
Nowhere near icing though, agreed.
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..........