Macchi Castoldi MC.72 03

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Moving Things in Still Pictures!

"®i©ardo" wrote in message
...

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Moving Things in Still Pictures!





Well, that's an interesting engine arrangement. (to put it mildly)


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Cheers

Dave Kearton

On 19/03/2013 19:26, Dave Kearton wrote:
"®i©ardo" wrote in message
...

--
Moving Things in Still Pictures!





Well, that's an interesting engine arrangement. (to put it mildly)



Hi Dave,

Yes, as explained to Indrek:

"Macchi-Castoldi MC-72 Fiat AS6 engine; dual V-12, 3100 total HP,
each engine drives one very course, fixed-pitch prop 440.729 mph in
1934. Class record still stands. Why contra-prop? Supermarine S6B w/
2650 HP on single prop overloaded one float by 32% on takeoff due to
torque."

Regards,

Ri©ardo

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Moving Things in Still Pictures!

"®i©ardo" wrote in message
...
On 19/03/2013 19:26, Dave Kearton wrote:

Hi Dave,

Yes, as explained to Indrek:

"Macchi-Castoldi MC-72 Fiat AS6 engine; dual V-12, 3100 total HP,
each engine drives one very course, fixed-pitch prop 440.729 mph in 1934.
Class record still stands. Why contra-prop? Supermarine S6B w/ 2650 HP on
single prop overloaded one float by 32% on takeoff due to torque."

Regards,

Ri©ardo




What fascinated me is the engineering work required to get the job done.
Not only are there two unique engines inline, but the crankshafts can't be
simply bolted together.

I've been thinking about it for a while now and I can't think of a simple
way to do it reliably.


All that effort and expense for a one-off design. Absolutely outstanding
that they got it to work at all, much less in the '30s.




--



Cheers

Dave Kearton

On 19/03/2013 22:02, Dave Kearton wrote:
"®i©ardo" wrote in message
...
On 19/03/2013 19:26, Dave Kearton wrote:

Hi Dave,

Yes, as explained to Indrek:

"Macchi-Castoldi MC-72 Fiat AS6 engine; dual V-12, 3100 total HP,
each engine drives one very course, fixed-pitch prop 440.729 mph in
1934. Class record still stands. Why contra-prop? Supermarine S6B w/
2650 HP on single prop overloaded one float by 32% on takeoff due to
torque."

Regards,

Ri©ardo




What fascinated me is the engineering work required to get the job done.
Not only are there two unique engines inline, but the crankshafts can't
be simply bolted together.

I've been thinking about it for a while now and I can't think of a
simple way to do it reliably.


All that effort and expense for a one-off design. Absolutely
outstanding that they got it to work at all, much less in the '30s.





It shows the prestige attached to the Schneider Trophy and it also
spurred development of European WWII fighter aircraft. There's a superb
article on the subject he

http://www.airspacemag.com/history-o...schneider.html

....all seven pages of it.

Hmm, have also just spotted a typo in the original lifted article whe
"one very *course* , fixed-pitch prop..." should surely read "coarse"!

Regards,

Ri©ardo

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Moving Things in Still Pictures!

On Wed, 20 Mar 2013 08:32:20 +1030, "Dave Kearton"
wrote:

"®i©ardo" wrote in message
m...
On 19/03/2013 19:26, Dave Kearton wrote:

Hi Dave,

Yes, as explained to Indrek:

"Macchi-Castoldi MC-72 Fiat AS6 engine; dual V-12, 3100 total HP,
each engine drives one very course, fixed-pitch prop 440.729 mph in 1934.
Class record still stands. Why contra-prop? Supermarine S6B w/ 2650 HP on
single prop overloaded one float by 32% on takeoff due to torque."

Regards,

Ri©ardo




What fascinated me is the engineering work required to get the job done.
Not only are there two unique engines inline, but the crankshafts can't be
simply bolted together.

I've been thinking about it for a while now and I can't think of a simple
way to do it reliably.

Sounds like the designers had the same problem - didn't Ricardo
mention that two of the three examples crashed?

All that effort and expense for a one-off design. Absolutely outstanding
that they got it to work at all, much less in the '30s.

And how much faster would it have been without the floats?

On 20/03/2013 09:43, lid wrote:
On Wed, 20 Mar 2013 08:32:20 +1030, "Dave Kearton"
wrote:

"®i©ardo" wrote in message
...
On 19/03/2013 19:26, Dave Kearton wrote:

Hi Dave,

Yes, as explained to Indrek:

"Macchi-Castoldi MC-72 Fiat AS6 engine; dual V-12, 3100 total HP,
each engine drives one very course, fixed-pitch prop 440.729 mph in 1934.
Class record still stands. Why contra-prop? Supermarine S6B w/ 2650 HP on
single prop overloaded one float by 32% on takeoff due to torque."

Regards,

Ri©ardo




What fascinated me is the engineering work required to get the job done.
Not only are there two unique engines inline, but the crankshafts can't be
simply bolted together.

I've been thinking about it for a while now and I can't think of a simple
way to do it reliably.

Sounds like the designers had the same problem - didn't Ricardo
mention that two of the three examples crashed?


That was the Fiat C.29: "This aircraft was designed for the 1929
Schneider Trophy air race, although did not compete in the end with the
first and second prototypes crashing, this being the third -
non-competing - sole survivor."


All that effort and expense for a one-off design. Absolutely outstanding
that they got it to work at all, much less in the '30s.

And how much faster would it have been without the floats?


Given the lack of space for retractable undercarriage, would the
alternative be any more aerodynamically efficient?

--
Moving Things in Still Pictures!

On 3/19/2013 5:02 PM, Dave Kearton wrote:
"®i©ardo" wrote in message
...
On 19/03/2013 19:26, Dave Kearton wrote:

Hi Dave,

Yes, as explained to Indrek:

"Macchi-Castoldi MC-72 Fiat AS6 engine; dual V-12, 3100 total HP,
each engine drives one very course, fixed-pitch prop 440.729 mph in
1934. Class record still stands. Why contra-prop? Supermarine S6B w/
2650 HP on single prop overloaded one float by 32% on takeoff due to
torque."

Regards,

Ri©ardo




What fascinated me is the engineering work required to get the job done.
Not only are there two unique engines inline, but the crankshafts can't
be simply bolted together.

I've been thinking about it for a while now and I can't think of a
simple way to do it reliably.


All that effort and expense for a one-off design. Absolutely outstanding
that they got it to work at all, much less in the '30s.


It was the early 1930s? There weren't many engines on the shelf to
chose from, and NONE that size...

The seaplane races were intended to advance aviation technology.
AND national pride was at stake here.