Why didn't the Cessna 337 make it?

On 2006-02-28, Matt Whiting wrote:
Hard to imagine a pilot so sensory impaired that he or she can't detect
the loss of 50% of their power, which results in lost of far more than
50% of most performance attributes. I'd really not want to fly with a
pilot who was that out of touch with their airplane.

I don't think that was necessarily the problem - imagine being just
airborne on an obstructed and reasonably short airfield, then one of the
engines quit. Although you feel the loss of thrust, it's not obvious
which engine has actually failed from the yaw because there isn't any.
Add to that the typical market segment for a 337 (people who percieve
they won't be safe enough in a normal twin) and you're asking for
trouble.

The only way of figuring out which engine has quit short of pulling a
throttle back and see if you lose even *more* power (which is
ineffective if one engine is only losing partial power) is to look at
the gauges. You might not even notice the loss of an engine if it
happens on approach until you throttle up for a go-around and find up to
50% of your power is missing (if an engine fails on approach, the only
indication may be a decreasing EGT - the windmilling prop may still
make the same RPM and the manifold pressure does not change if an
engine isn't actually combusting fuel). Even if one fails on takeoff,
where the failed engine will almost certainly lose RPM you still have to
look at and interpret the gauges which is a slower process (particularly
if it's a high workload instrument departure) than 'dead foot dead
engine'.

The people who are liable to VMC roll a conventional twin are probably
the same people who will stall a 337 while taking their time over trying
to figure out which engine has quit.

--
Dylan Smith, Port St Mary, Isle of Man
Flying: http://www.dylansmith.net
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In article ,
says...

Add to that the typical market segment for a 337 (people who percieve
they won't be safe enough in a normal twin) and you're asking for
trouble.


The people who are liable to VMC roll a conventional twin are probably
the same people who will stall a 337 while taking their time over trying
to figure out which engine has quit.

--

Your point is well taken - the "Cirrus Syndrome" of creating a market
sector specifically for those who are doubtful of their own abilities...

However, in light twins this could be more a question of lucidity than
anything else. If the "conventional twin" you refer to is a KingAir, or
something with ample power and ample VYSE, then fine. But remember, in light
twins, which have "just enough" power to demonstrate SE climb, most pilots
faced with real-world situation do not succeed in performing the type of
recovery they demonstrated on their ME checkride.

It's not just a control issue - many of the small singles that "grew up"
into twins have so little excess horsepower available that the recovery must
be perfectly executed in order to be effective. Most of us would have to
admit that we can not always be counted on to do everything perfectly,
particularly under duress, and this is not to mention the fact that the
incident does not necessarily occur at sea level, at standard atmospheric
conditions. Many of the incidents are probably unrecoverable, or very close
to it from the get go.

Adding extra power to deal with this quickly moves one into the 421 or Duke
category, where the plane may not spiral out of control so much as the
operating costs - for a feature that is essentially there only for emergency
use. Suddenly, the ugly little 337 starts to look a whole lot prettier, and
that 'uncertainty' begins to look a lot like just plain good judgement.

All of the above does not really contradict your argument, as you were
talking about perception - and pilots as well as regulators tend to perceive
themselves as capable, and therefore safer in a standard twin than in a
single - even though the accident record has repeatedly disproven this.

GF

"Dylan Smith" wrote in message
...
[...]
The people who are liable to VMC roll a conventional twin are probably
the same people who will stall a 337 while taking their time over trying
to figure out which engine has quit.

I don't see how this is an issue. With centerline thrust, the pilot
shouldn't NEED to know which engine has quit. The primary reason for
knowing which engine has quit in a convential twin is so you can use the
correct control inputs. With centerline thrust, you just keep flying the
airplane. Why would any pilot spend any time trying to figure out which
engine has quit on a 337? What are they going to do with that information,
at least in the immediate sense?

Pete

"Peter Duniho" wrote in message
...
I don't see how this is an issue. With centerline thrust, the pilot
shouldn't NEED to know which engine has quit.

Perhaps there is a need to feather the prop on the dead engine to cut drag?

"Grumman-581" wrote in message
...
Perhaps there is a need to feather the prop on the dead engine to cut
drag?

Ahh...good point, thanks.

Sorry Duniho, the "dufus" guy was somebody else. My mistake.
Dudley Henriques

"Peter Duniho" wrote in message
...
"Grumman-581" wrote in message
...
Perhaps there is a need to feather the prop on the dead engine to cut
drag?

Ahh...good point, thanks.

Dudley

Go over the proedure for the troops about losing the wrong engine on
Take Off and having to leave the engine wind milling to have enough
hydraulic pressure to slowly retract the gear before you can feather
the prop and the donut rings you cut doing this.

Big John
`````````````````````````````````````````````````` ```````````````
On Tue, 28 Feb 2006 21:51:35 GMT, "Dudley Henriques"
wrote:

Sorry Duniho, the "dufus" guy was somebody else. My mistake.
Dudley Henriques

"Peter Duniho" wrote in message
...
"Grumman-581" wrote in message
...
Perhaps there is a need to feather the prop on the dead engine to cut
drag?

Ahh...good point, thanks.

You need to know hoe to identify the dead engine and feather
the correct prop, otherwise you're going down. In a
conventional twin identification is holding heading with
rudder, "dead foot dead engine" and the litany is

CONTROL
POWER (up)
DRAG (gear and flaps)
IDENTIFY
VERIFY
FEATHER
FLY

secure it

In the 336/337 it isn't as easy or obvious which engine is
sick or dead.

--
James H. Macklin
ATP,CFI,A&P

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"Peter Duniho" wrote in
message ...
| "Dylan Smith" wrote in message
| ...
| [...]
| The people who are liable to VMC roll a conventional
twin are probably
| the same people who will stall a 337 while taking their
time over trying
| to figure out which engine has quit.
|
| I don't see how this is an issue. With centerline thrust,
the pilot
| shouldn't NEED to know which engine has quit. The primary
reason for
| knowing which engine has quit in a convential twin is so
you can use the
| correct control inputs. With centerline thrust, you just
keep flying the
| airplane. Why would any pilot spend any time trying to
figure out which
| engine has quit on a 337? What are they going to do with
that information,
| at least in the immediate sense?
|
| Pete
|
|

"Peter Duniho" wrote in message
...
"Dylan Smith" wrote in message
...
[...]
The people who are liable to VMC roll a conventional twin are probably
the same people who will stall a 337 while taking their time over trying
to figure out which engine has quit.

I don't see how this is an issue. With centerline thrust, the pilot
shouldn't NEED to know which engine has quit. The primary reason for
knowing which engine has quit in a convential twin is so you can use the
correct control inputs. With centerline thrust, you just keep flying the
airplane. Why would any pilot spend any time trying to figure out which
engine has quit on a 337? What are they going to do with that
information, at least in the immediate sense?

Pete

With a conventional twin you "just keep flying the airplane" as well. It's
HOW you keep flying the airplane that matters.
Any "dufus" as you have said, who thinks that just because those engines are
in line on the 337 means you don't have a prop drag issue with engine
failure needs to go out on a hot Sunday afternoon on a short runway with
trees at the end and lose one at rotation!
Dudley Henriques

Dylan Smith wrote:
On 2006-02-28, Matt Whiting wrote:

Hard to imagine a pilot so sensory impaired that he or she can't detect
the loss of 50% of their power, which results in lost of far more than
50% of most performance attributes. I'd really not want to fly with a
pilot who was that out of touch with their airplane.


I don't think that was necessarily the problem - imagine being just
airborne on an obstructed and reasonably short airfield, then one of the
engines quit. Although you feel the loss of thrust, it's not obvious
which engine has actually failed from the yaw because there isn't any.
Add to that the typical market segment for a 337 (people who percieve
they won't be safe enough in a normal twin) and you're asking for
trouble.

In a center-line twin, why does it matter which engine failed? You have
to adjust to the reduced thrust no matter which engine gave up, right?
Sure, you need to feather the correct prop and secure the dead engine,
but that doesn't have to be done in the first millisecond after failure.
And it isn't that hard to look at the gauges and decide which one quit.

Matt