Can we put the myth that singles are as safe as twins to bed now?
From what I witnessed following a few hours P2 in a Twin Commanche alongside a superb P1, I'd say the other salient variable is workload, or at least the potential for workload to square rapidly if things stop working as advertised. It is very easy to point to cases of mishandled engine failures and declare a training deficit (plausibly so in some cases, and I think Pace and others make some excellent points) but it also depends on how high the workload was at the time. As WSMempson said, twins tend to be operated differently and from my own very limited twin experience, they do appear more demanding in terms of monitoring, and operating more complex nav equipment - at faster speeds than are typical for most SEP flights. One might say twins are operated quite similarly to Cirrus SR20/22 so perhaps we have been comparing the wrong fruits...
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Workload ? Yes a twin is faster but then the jet I fly is a lot faster than the twin! Is the jet harder ? I would say no but not having flown a single for a while I might find a single harder!
Everything is relative including speed and in some respects a Jet is easy to fly I also find a twin is easy to fly but maybe workload is more to do with lack of familiarity!
If it fits like a glove you do not need to think when operating the aircraft and that goes for single, twin , jet !
Pace
Workload ? Yes a twin is faster but then the jet I fly is a lot faster than the twin! Is the jet harder ? I would say no but not having flown a single for a while I might find a single harder!
Everything is relative including speed and in some respects a Jet is easy to fly I also find a twin is easy to fly but maybe workload is more to do with lack of familiarity!
If it fits like a glove you do not need to think when operating the aircraft and that goes for single, twin , jet !
Pace
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I'd say the old twins (you know, the ones with 6 levers 
) are hardest to fly. The new FADEC twins are much easier to fly. I then flew the Citation Mustang and that is easier to fly than both of the others , and if you are used to the G1000 setup of the Twin Star, a doddle. The only thing is that it is a bit quicker and things happen a bit faster but all in all it is a piece of p*ss to fly and even easier than the Twin Star when it comes to engine out.
(Emergency decent was the most fun bit of my training - 17000 to 9000 in 45 sec - which is a vertical speed faster than a free fall parachutist
).
Begs the question....why hasn't FADEC made it to the petrol engines?
) are hardest to fly. The new FADEC twins are much easier to fly. I then flew the Citation Mustang and that is easier to fly than both of the others , and if you are used to the G1000 setup of the Twin Star, a doddle. The only thing is that it is a bit quicker and things happen a bit faster but all in all it is a piece of p*ss to fly and even easier than the Twin Star when it comes to engine out.(Emergency decent was the most fun bit of my training - 17000 to 9000 in 45 sec - which is a vertical speed faster than a free fall parachutist
).Begs the question....why hasn't FADEC made it to the petrol engines?
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its is strange that in a jet up high you have no feeling of speed, a waypoint 400 nm away seems to take forever and you then wish your jet would fly at 1000 kts.
the same goes for a single and a twin.
Where speed does come into it is when you get behind the aircraft and that can easily happen in a single flying low level at 70 KTS a twin flying at 120 KTS or a jet flying at 250 KTS.
In a jet you usually have an FO so He/She takes a lot of the load (A good one They do most of the mundane work allowing you the Captain to sit back and look the part
A bad one and they increase the load as you are forever checking or rectifying what they do 
you need to be so familiar with the aircraft that your hands instinctively fly around the cockpit to the correct switches with little brain power involved.
Only then is your brain power freed up to deal with the unexpected.
If your brain power is struggling to simply fly the aircraft any additional loading from the unexpected soon overloads and the workload becomes too much.
Pace
the same goes for a single and a twin.
Where speed does come into it is when you get behind the aircraft and that can easily happen in a single flying low level at 70 KTS a twin flying at 120 KTS or a jet flying at 250 KTS.
In a jet you usually have an FO so He/She takes a lot of the load (A good one They do most of the mundane work allowing you the Captain to sit back and look the part
A bad one and they increase the load as you are forever checking or rectifying what they do you need to be so familiar with the aircraft that your hands instinctively fly around the cockpit to the correct switches with little brain power involved.
Only then is your brain power freed up to deal with the unexpected.
If your brain power is struggling to simply fly the aircraft any additional loading from the unexpected soon overloads and the workload becomes too much.
Pace
Last edited by Pace; 8th Jan 2014 at 08:59.
I agree with you Pace, never a truer word spoken - clearly knowledge, training, currency and therefore familiarity can be reasonably considered components of competence. What I didn't explain at all well in my post was that workload, as a term, relates better to how busy you are, rather than how easy or difficult something is to operate. Although obviously there is a simplistic correlation between the two!
Even Bob Hoover (insert skygod of choice here....) would be busier approaching in a 90 degree crosswind than he would be into wind, even though the task itself would present no problem to him. So returning to the SEP v light twins debate, I would reasonably expect an aircraft with more systems to have greater potential to take even the most competent operator from being not very busy to incredibly busy in a shorter space of time!
Even Bob Hoover (insert skygod of choice here....) would be busier approaching in a 90 degree crosswind than he would be into wind, even though the task itself would present no problem to him. So returning to the SEP v light twins debate, I would reasonably expect an aircraft with more systems to have greater potential to take even the most competent operator from being not very busy to incredibly busy in a shorter space of time!
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More systems generally result in more capability, and therefore easier to handle in similar circumstances. A 150 horse Apache with one caged landing in a gusty XW at a 4,000' elevation airport vs a 737 with one out doing the same thing, as an example.
Complication or capability?
Complication or capability?
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Only as complex as you make it
The question is a single engine as safe as a Twin is
only complex if you throw in all the variables. Like
the fact that the Aircraft manufacturers built a lot
of piston twins in the 50s and 60s that will not fly
on one engine at gross weight. And a lot of these
aircraft are in the hands of Pilots that barely fly
enough to maintain currency. But if you boil the
argument down to its essence, the only thing a
multi engine aircraft offers over a single engine
machine is a redundant power supply, so out of
all engine failures, single or multi, commercial
or private how many of each group make safe
landings. The problem is going to be coming up
with this number. If you have an engine failure
on a multi engine aircraft and make a safe
landing, with no damage or injuries their are
rarely any reports submitted to the FAA or NTSB
for the public to access. Case in point, in Alaska
they use DC6s a 4 engine machine to haul freight,
in 13 years hardly a month went by without seeing
one of these machines coming home with an engine
feathered, Ive even seen one DC6 come back with
two engines feathered on the same side, as I was
doing maintenance on these aircraft i was never
asked one time by the FAA for a report on an
engine failure. If you are having a debate on
which is safer a single or multi engine aircraft
shouldn't these numbers be plugged into the
equation. Out of all the multi engine aircraft
I witnessed with engine failures only one did
not come back, out of the single engine aircraft
with power failure only one Cessna Caravan
made a successful dead stick landing. 20 years
in aviation has taught me one thing for sure
aircraft power plants are designed, built and
maintained by men, and no matter what type
of power plant you have turbine or piston
if you run it long enough it will fail. Even
Pratt & Whitney says the failure rate of the
PT6 turbine engine goes up dramatically after
the third overhaul.
only complex if you throw in all the variables. Like
the fact that the Aircraft manufacturers built a lot
of piston twins in the 50s and 60s that will not fly
on one engine at gross weight. And a lot of these
aircraft are in the hands of Pilots that barely fly
enough to maintain currency. But if you boil the
argument down to its essence, the only thing a
multi engine aircraft offers over a single engine
machine is a redundant power supply, so out of
all engine failures, single or multi, commercial
or private how many of each group make safe
landings. The problem is going to be coming up
with this number. If you have an engine failure
on a multi engine aircraft and make a safe
landing, with no damage or injuries their are
rarely any reports submitted to the FAA or NTSB
for the public to access. Case in point, in Alaska
they use DC6s a 4 engine machine to haul freight,
in 13 years hardly a month went by without seeing
one of these machines coming home with an engine
feathered, Ive even seen one DC6 come back with
two engines feathered on the same side, as I was
doing maintenance on these aircraft i was never
asked one time by the FAA for a report on an
engine failure. If you are having a debate on
which is safer a single or multi engine aircraft
shouldn't these numbers be plugged into the
equation. Out of all the multi engine aircraft
I witnessed with engine failures only one did
not come back, out of the single engine aircraft
with power failure only one Cessna Caravan
made a successful dead stick landing. 20 years
in aviation has taught me one thing for sure
aircraft power plants are designed, built and
maintained by men, and no matter what type
of power plant you have turbine or piston
if you run it long enough it will fail. Even
Pratt & Whitney says the failure rate of the
PT6 turbine engine goes up dramatically after
the third overhaul.
