For Morgans ...Rotax (x 2)

Here you go Jim - From NC,

Pusher-Puller Twin-Rotax 582's ...Italian job. G G

http://www.flylab.it/tucano2ve.htm
TUCANO Delta3 VTW

http://www.flylab.it/tucano2e.htm
TUCANO Delta3 TW

"The Tucano Delta3 TW (twin-engine) represents the successful attempt to
cope with the quite often disagreeable consequences of an engine breakdown.
It has been extensively tested with excellent result."



Montblack

On Wed, 26 Apr 2006 22:42:17 -0500, "Montblack"
wrote:

"The Tucano Delta3 TW (twin-engine) represents the successful attempt to
cope with the quite often disagreeable consequences of an engine breakdown.
It has been extensively tested with excellent result."

All it means is that you've got twice the chance of having an engine failure....

Ron Wanttaja

"Ron Wanttaja" wrote in message
...
On Wed, 26 Apr 2006 22:42:17 -0500, "Montblack"
wrote:

"The Tucano Delta3 TW (twin-engine) represents the successful attempt to
cope with the quite often disagreeable consequences of an engine
breakdown.
It has been extensively tested with excellent result."

All it means is that you've got twice the chance of having an engine
failure....

Ron Wanttaja

And half the chance of it killing you

On Thu, 27 Apr 2006 03:53:17 GMT, "Ian Mitchell"
wrote:


"Ron Wanttaja" wrote in message
.. .
On Wed, 26 Apr 2006 22:42:17 -0500, "Montblack"
wrote:

"The Tucano Delta3 TW (twin-engine) represents the successful attempt to
cope with the quite often disagreeable consequences of an engine
breakdown.
It has been extensively tested with excellent result."

All it means is that you've got twice the chance of having an engine
failure....

And half the chance of it killing you

Mmmmmmm....no. An engine failure in a single-engined airplane requires a
deadstick landing. Bad, yes, depending on where it happens, but the pilot uses
the same skills he or she uses on every flight. An engine failure on a
twin-engine plane puts the pilot in an unusual mode of flight. Yes, a pilot
with current skills and the right training will have a better chance to bring
the aircraft home intact. But in the real world, it doesn't work out that way.
*Any* emergency is bad. Pilots die after engine failures in twins, too.

The Tucano should avoid some of the problems due to centerline thrust, but the
fact is, it has twice the fuel burn, twice the propellers, twice the ignition
sources, and twice the exhaust heat of a single-engined airplane. There are
more things to break, more chances to lose power unexpectedly, more chances to
mismanage fuel, and more things that can start fires.

Two stroke engines are about twice as apt to quit than "conventional" aircraft
engines. The solution is not to use *two* of them, but a single more-reliable
powerplant.

As for those wonder how eager the market is for twin-two-stroke
centerline-thrust airplanes, I just have three words: Powers. Bashforth.
Minimaster.

Ron Wanttaja

..5 reliable component x .5 reliable component = .25 reliable system.

also, .9 x.9 = .81, just for argument sake.



Richard

That's not a complete picture. It just so happens that I have an exam on
Safety, Risk & Reliability tomorrow.

There's a good reason why airliners have more than one engine. The idea is
that they can make it to an airport on just half of their engines. This is
known as redundancy.

So, if your plane has two engines, each with a reliability, r, of 0.9 (
that's a 1 in 10 failure rate, reliabilities are much higher than this in
reality), and only needs one engine to make it to a safe landing site, your
overall reliability will be

Following some maths (let me know if you want a full explanation) we get,

System reliability = 2r - r^2

Therefore reliability = (2*0.9) - (r*r)
= 1.8 - 0.81 = 0.99

So, providing that it can fly on just one engine you have a much lower
chance of walking out of a field you never walked into.

If you are relying on two out of four engines (r = 0.9 again) your
reliability is up to 0.9963.

This does, of course, leave the problem of piloting a plane with imperfect
flying characteristics, but it gives you more time to deal with the problem

Finally if the plane can't make it home on half engines, don't fly it. As
Richard points out your reliability decreases.

Ed

On 27/4/06 9:29 am, in article , "Richard
Lamb" wrote:

.5 reliable component x .5 reliable component = .25 reliable system.


also, .9 x.9 = .81, just for argument sake.



Richard

"Richard Lamb" wrote in message
...
.5 reliable component x .5 reliable component = .25 reliable system.

also, .9 x.9 = .81, just for argument sake.



Richard

Yep. That's why I fly a Schweizer 1-26. I don't believe there has ever
been an engine failure in a 1-26.

Tim Ward

"Montblack" wrote

Here you go Jim - From NC,

Pusher-Puller Twin-Rotax 582's ...Italian job. G G

"The Tucano Delta3 TW (twin-engine) represents the successful attempt to
cope with the quite often disagreeable consequences of an engine
breakdown.
It has been extensively tested with excellent result."

First of all, let me say, "you are really cruel."

That out of the way, g even if it had 69 Rotax 582's, I would not get into
it. The two strokes are not suitable for flight, IMHO. They belong in Sea
Doo jet skls, where WHEN they quit, you can sit and wait for a tow back to
the dock.

If they used two stroke Rotax engines, I might be talked into _riding_ in
one, depending on their single engine service ceiling, and other performance
parameters, with one engine out. The saying about "two engines means there
is always an engine running, to get you to the scene of the crash" holds too
much truth.

I still would not own one, because there still is an engine to keep running,
and now there are two engines to keep running. It sounds like a maintanence
headache, to me.

It sure is an ugly little beastie, isn't it? I though the Italians were
supposed to be known for their sexy, stylish sports cars, and stuff. It
sure didn't carry through to this airplane.

You just love throwing salt into open wounds, dont't you? Shame on you!
;-)

Snip "relevent fact"

Don't confuse the issue with facts, they don't want to change an earnestly
held pre-concieved notion.

Ian

" Mmmmmmm....no. An engine failure in a single-engined airplane requires a
deadstick landing. Bad, yes, depending on where it happens, but the pilot
uses
the same skills he or she uses on every flight."

Mmmmm...no the problem is most GA pilots use powered approaches,
particularly flying into controlled airfields during a normal flight. A
"deadstick" presents them with an opportunity for poor decision making.


An engine failure on a
twin-engine plane puts the pilot in an unusual mode of flight. Yes, a
pilot
with current skills and the right training will have a better chance to
bring
the aircraft home intact. But in the real world, it doesn't work out that
way.
*Any* emergency is bad. Pilots die after engine failures in twins, too.

Yes, usually associated with asymetric control issues. I'm guessing more get
home after a single engine failure than don't.


The Tucano should avoid some of the problems due to centerline thrust, but
the
fact is, it has twice the fuel burn, twice the propellers, twice the
ignition
sources, and twice the exhaust heat of a single-engined airplane. There
are
more things to break, more chances to lose power unexpectedly, more
chances to
mismanage fuel, and more things that can start fires.

Fair comment, except that the single engine performance in cruise suggests
that may be a "normal" mode of operation. I think the potential for this
aircraft is in operations over water, hostile terrain. Maritime or forestry
patrol etc.


Two stroke engines are about twice as apt to quit than "conventional"
aircraft
engines. The solution is not to use *two* of them, but a single
more-reliable
powerplant.

Before I converted to ultralights from GA, I was pretty concerned that one
day the fire would go out and bad things would happen. I never had an engine
failure in GA, and I haven't had one in an ultralight yet either, but I'm
not concerned about it, when you do most of your flying at 500' or less, you
are always noting the location of the best forced landing area, taking the
long way around "tiger" country etc. The problem with conventional 4 stroke
aircraft engines has been weight, and the need to put them into a bigger
heavier airframe. I'm very encouraged by the developement of engines like
the HKS and Warner, as they appear to offer a nice blend of light
weight/power/reliability.



As for those wonder how eager the market is for twin-two-stroke
centerline-thrust airplanes, I just have three words: Powers. Bashforth.
Minimaster.

Don't know anything about those, my only comment would be that the problem
may have been a business, marketing etc issue and not the concept in
general.

Ian