props: tractor v pusher, q tip, ducted?

I flew the 0-2 in VN. Single engine performance, either front or rear,
was not very good. That being said, the rear engine gave better SE
performance. We were told in ground school that the rear prop sucked
air over the wing center section at a higher velocity and gave more
lift than the front engine could push it up and over the center of
wing.

No matter the reason, the bird flew better SE on rear engine. SE on
either engine, the machine turned into a donut making device or worse
if you were not careful.

Big John
****************************************888

On Sun, 5 Aug 2007 22:15:55 -0400, "Kyle Boatright"
wrote:


"Kingfish" wrote in message
roups.com...
On Aug 5, 8:27 pm, Tony wrote:
If one uses the Cessna 377 Skymaster as an example, it's pretty clear
a pusher prop is more efficient than one pulling.

It is? How do you figure, seeing as the 337 has a tractor AND a pusher
prop?

The single engine climb performance is pitiful regardless of which engine is
caged, but the aircraft has more performance on the back engine than the
front. That may or may not be due to prop efficiency. It could also be due
to reduced fuselage drag. The tractor prop blows a high speed stream of air
across the fuselage, creating its own source of drag. This isn't as much of
a factor with the pusher.

KB

I would have thought the gain for the rear engine was because the air
stream was not hitting the windscreen and losing energy that way. The
air coming into the prop comes from all directions (just flowing into
a low pressure area) but the stream leaving is directed.

But if in the newer Skymasters both engines give the same single
engine performance my idea has to be wrong






On Aug 9, 2:28 pm, Big John wrote:
I flew the 0-2 in VN. Single engine performance, either front or rear,
was not very good. That being said, the rear engine gave better SE
performance. We were told in ground school that the rear prop sucked
air over the wing center section at a higher velocity and gave more
lift than the front engine could push it up and over the center of
wing.

No matter the reason, the bird flew better SE on rear engine. SE on
either engine, the machine turned into a donut making device or worse
if you were not careful.

Big John
****************************************888

On Sun, 5 Aug 2007 22:15:55 -0400, "Kyle Boatright"



wrote:

"Kingfish" wrote in message
roups.com...
On Aug 5, 8:27 pm, Tony wrote:
If one uses the Cessna 377 Skymaster as an example, it's pretty clear
a pusher prop is more efficient than one pulling.

It is? How do you figure, seeing as the 337 has a tractor AND a pusher
prop?

The single engine climb performance is pitiful regardless of which engine is
caged, but the aircraft has more performance on the back engine than the
front. That may or may not be due to prop efficiency. It could also be due
to reduced fuselage drag. The tractor prop blows a high speed stream of air
across the fuselage, creating its own source of drag. This isn't as much of
a factor with the pusher.

KB- Hide quoted text -

- Show quoted text -

Tina

I can only tell you what Air Force ground school said when checking us
out in 0-2. Know from experience that SE rear was better than SE front
engine. Not much, but better.

Big John
*********************************************

On Thu, 09 Aug 2007 16:36:56 -0700, Tina
wrote:

I would have thought the gain for the rear engine was because the air
stream was not hitting the windscreen and losing energy that way. The
air coming into the prop comes from all directions (just flowing into
a low pressure area) but the stream leaving is directed.

But if in the newer Skymasters both engines give the same single
engine performance my idea has to be wrong






On Aug 9, 2:28 pm, Big John wrote:
I flew the 0-2 in VN. Single engine performance, either front or rear,
was not very good. That being said, the rear engine gave better SE
performance. We were told in ground school that the rear prop sucked
air over the wing center section at a higher velocity and gave more
lift than the front engine could push it up and over the center of
wing.

No matter the reason, the bird flew better SE on rear engine. SE on
either engine, the machine turned into a donut making device or worse
if you were not careful.

Big John
****************************************888

On Sun, 5 Aug 2007 22:15:55 -0400, "Kyle Boatright"



wrote:

"Kingfish" wrote in message
roups.com...
On Aug 5, 8:27 pm, Tony wrote:
If one uses the Cessna 377 Skymaster as an example, it's pretty clear
a pusher prop is more efficient than one pulling.

It is? How do you figure, seeing as the 337 has a tractor AND a pusher
prop?

The single engine climb performance is pitiful regardless of which engine is
caged, but the aircraft has more performance on the back engine than the
front. That may or may not be due to prop efficiency. It could also be due
to reduced fuselage drag. The tractor prop blows a high speed stream of air
across the fuselage, creating its own source of drag. This isn't as much of
a factor with the pusher.

KB- Hide quoted text -

- Show quoted text -