http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.

On 18/03/2014 09:02, harryagain wrote:
http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

Is this the Wankel one with that weird triangular piston rotaor?

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


"Nightjar" wrote in message
...
On 18/03/2014 09:02, harryagain wrote:
http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it needs
no additional flywheel, would have been just as important in an early
motor car as it was in early aircraft.

Colin Bignell

On 18/03/2014 23:39, Brian Gaff wrote:
Is this the Wankel one with that weird triangular piston rotaor?

No, it is a 19th century design, with five air cooled cylinders that
rotate around a fixed vertical crankshaft. Having the cylinders rotating
does away with the need for a flywheel, giving a good power to weight
ratio, and creates a forced draught over them that improves cooling
efficiency.

Similar designs were used in world war I fighter aircraft. However, the
gyroscopic effect made turning them rather interesting.

Colin Bignell

On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:
http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).

On Sat, 22 Mar 2014 12:08:38 +0000, Part Timer wrote:

http://www.youtube.com/embed/Y0XbqHUAI-0
Heh. I knew these were used on aircraft but not in cars.

A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

I'd have called it a radial engine, not a rotary (Wankel).

Nope, that's definitely a rotary. It's not a Wankel, but it's not a
radial, either.

On radials, the cylinders were static and the crankshaft rotated. Just
like a normal V engine but with banks all the way round.

On a rotary, the crank is static, and the cylinders rotate, just like
that one. Think WW1 fighter plane.
http://en.wikipedia.org/wiki/Rotary_engine

A Wankel is the NSU/Mazda-style one that everybody thinks of as "rotary",
with static cylinders, triangular rotor geared to and spinning around the
crank.

On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic



--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

On 22/03/2014 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.


I'd have called it a radial engine, not a rotary (Wankel).

Although described as a rotary engine, the Wankel is an entirely
different beast.

Radial and rotary engines both have a number of cylinders arrange around
the crankshaft. Visually, they are similar when stationary. However, the
defining difference is whether the crankshaft rotates, which makes it a
radial engine, or the cylinders rotate, which makes it a rotary engine.

Colin Bignell

On 22/03/2014 12:28, The Natural Philosopher wrote:
On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic



Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

On 22/03/14 14:44, wrote:


Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

Nevertheless most of them were.

VERY few really fast piston engined aircraft had radials.

And the big ones with multiple banks all had cooling issues

--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

wrote in message
...
On 22/03/2014 12:28, The Natural Philosopher wrote:
On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic



Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

Air cooled aero engines have major cooling problems when flying.
Eg
When descending they over cool and the cylinders can seize onto the pistons.
At best it causes high wear and tear.

If you look at radial engines, there is a circle of flaps round the engine
nacelle which are closed on descent.

One some aircraft it is recommended to side slip in when landing for rapid
descent to the reduce the cooling effect.

So "someone" didn't have a clue.

"The Natural Philosopher" wrote in message
...
On 22/03/14 14:44, wrote:


Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

Nevertheless most of them were.

VERY few really fast piston engined aircraft had radials.

And the big ones with multiple banks all had cooling issues


https://en.wikipedia.org/wiki/Fw190_F-8

On 22/03/2014 17:40, harryagain wrote:
wrote in message
...
On 22/03/2014 12:28, The Natural Philosopher wrote:
On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic



Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

Air cooled aero engines have major cooling problems when flying.
Eg
When descending they over cool and the cylinders can seize onto the pistons.
At best it causes high wear and tear.

If you look at radial engines, there is a circle of flaps round the engine
nacelle which are closed on descent.

One some aircraft it is recommended to side slip in when landing for rapid
descent to the reduce the cooling effect.

So "someone" didn't have a clue.


Err, it was a joke!

FWIW I've flown a wide range of aircraft, mostly with air-cooled
horizontally-opposed (Lycoming and Continental) engines but a few with
radials, in-line, turbine and part-water-cooled engines.

Your assertions are not correct.
Air-cooled engines do not have "major problems". Power vs speed needs
managing but the clearances are such that cooling is not, in practice, a
big problem up to a few hundred HP. Operations such as towing need
special care not to crack the heads, but this just means leaving a
little power and managing the acceleration in the 10 seconds
post-release (water-cooled is easier here).
Multi-row radials have their own cooling issues, as do high power
water-cooled engines such as the Merlin and Griffon.
Not all radials have cowl flaps but quite a few H-opposed engine
installations do; water-cooled aircraft have rad shutters.

I have never flown an aircraft in which side-slipping was recommended
for cooling - what type are you thinking of?

On Sat, 22 Mar 2014 20:16:47 +0000, Biggles wrote:

One some aircraft it is recommended to side slip in when landing for
rapid descent to the reduce the cooling effect.

I have never flown an aircraft in which side-slipping was recommended
for cooling - what type are you thinking of?

warning: utter amateur conjection beyond this point
Tailsliders often side-slip on landing - and there'd be a high crossover
with such older/smaller engine techs and tailsliders, right?

But - aiui - that's more to do with seeing wtf you're going than any kind
of cooling?

On 22/03/2014 20:51, Adrian wrote:
On Sat, 22 Mar 2014 20:16:47 +0000, Biggles wrote:

One some aircraft it is recommended to side slip in when landing for
rapid descent to the reduce the cooling effect.

I have never flown an aircraft in which side-slipping was recommended
for cooling - what type are you thinking of?

warning: utter amateur conjection beyond this point
Tailsliders often side-slip on landing - and there'd be a high crossover
with such older/smaller engine techs and tailsliders, right?

But - aiui - that's more to do with seeing wtf you're going than any kind
of cooling?


It's easier to fly a curved or slipping approach in aircraft with a long
nose or high thrust line because otherwise the runway disappears as you
come down the approach, shortly followed by the entire airfield in some
cases! By slipping, or only lining-up in the last few seconds, the
runway can be kept in sight. These aircraft are usually tailwheel
aircraft, often called "taildraggers" (rather than "tailsliders" ;-) )

On 22/03/2014 20:16, wrote:
On 22/03/2014 17:40, harryagain wrote:
wrote in message
...
On 22/03/2014 12:28, The Natural Philosopher wrote:
On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce
down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic



Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

Air cooled aero engines have major cooling problems when flying.
Eg
When descending they over cool and the cylinders can seize onto the
pistons.
At best it causes high wear and tear.

If you look at radial engines, there is a circle of flaps round the
engine
nacelle which are closed on descent.

One some aircraft it is recommended to side slip in when landing for
rapid
descent to the reduce the cooling effect.

So "someone" didn't have a clue.


Err, it was a joke!

FWIW I've flown a wide range of aircraft, mostly with air-cooled
horizontally-opposed (Lycoming and Continental) engines but a few with
radials, in-line, turbine and part-water-cooled engines.

Your assertions are not correct.
Air-cooled engines do not have "major problems". Power vs speed needs
managing but the clearances are such that cooling is not, in practice, a
big problem up to a few hundred HP. Operations such as towing need
special care not to crack the heads, but this just means leaving a
little power and managing the acceleration in the 10 seconds
post-release (water-cooled is easier here).
Multi-row radials have their own cooling issues, as do high power
water-cooled engines such as the Merlin and Griffon.
Not all radials have cowl flaps but quite a few H-opposed engine
installations do; water-cooled aircraft have rad shutters.

I have never flown an aircraft in which side-slipping was recommended
for cooling - what type are you thinking of?


.... forgot to say: the problem with cooling (leaving aside the exotic
multi-row radials) of air-cooled engines is because of the dissimilar
metals used for the heads and the valve seats. If, after a period at
high power, the power is rapidly reduced and the airspeed rapidly
increased, the head cools quickly and shrinks onto the valve seat; this
can result in a cracked head.

wrote in message
...
On 22/03/2014 17:40, harryagain wrote:
wrote in message
...
On 22/03/2014 12:28, The Natural Philosopher wrote:
On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce
down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic



Someone once told me that a water-cooled aircraft engine was about as
sensible as an air-cooled submarine engine ;-)

Air cooled aero engines have major cooling problems when flying.
Eg
When descending they over cool and the cylinders can seize onto the
pistons.
At best it causes high wear and tear.

If you look at radial engines, there is a circle of flaps round the
engine
nacelle which are closed on descent.

One some aircraft it is recommended to side slip in when landing for
rapid
descent to the reduce the cooling effect.

So "someone" didn't have a clue.


Err, it was a joke!

FWIW I've flown a wide range of aircraft, mostly with air-cooled
horizontally-opposed (Lycoming and Continental) engines but a few with
radials, in-line, turbine and part-water-cooled engines.

Your assertions are not correct.
Air-cooled engines do not have "major problems". Power vs speed needs
managing but the clearances are such that cooling is not, in practice, a
big problem up to a few hundred HP. Operations such as towing need special
care not to crack the heads, but this just means leaving a little power
and managing the acceleration in the 10 seconds post-release (water-cooled
is easier here).
Multi-row radials have their own cooling issues, as do high power
water-cooled engines such as the Merlin and Griffon.
Not all radials have cowl flaps but quite a few H-opposed engine
installations do; water-cooled aircraft have rad shutters.

I have never flown an aircraft in which side-slipping was recommended for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.

On Sat, 22 Mar 2014 21:48:34 +0000, Biggles wrote:

often called "taildraggers" (rather than "tailsliders" ;-) )

I was close, then... grin

On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
....
I have never flown an aircraft in which side-slipping was recommended for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

"Nightjar" wrote in message
...
On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
...
I have never flown an aircraft in which side-slipping was recommended
for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

It was never intended/designed to use it towing gliders.
Lots of take offs and landings/descents from around 3000'.
Our grouse was that the front cylinders wore out before the rear.
Even though the air is ducted.

On 23/03/2014 15:55, harryagain wrote:
"Nightjar" wrote in message
...
On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
...
I have never flown an aircraft in which side-slipping was recommended
for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

It was never intended/designed to use it towing gliders.
Lots of take offs and landings/descents from around 3000'.
Our grouse was that the front cylinders wore out before the rear.
Even though the air is ducted.


Interesting - I've towed with a Pawnee 235 and, once the post-release 10
seconds had been dealt with (and the CHT was below 200, I think) then
there was no need or recommendation to do anything other than fly it. I
can't recall the descent power settings or speed but the aim, as with
all towing, was to get back ASAP while controlling the rate of cooling
with power/speed, going no faster than Va (a bit of loading helps) and
keeping eyes out. The ROD was "adequate" without sideslip.

The view in the landing attitude was unusual, but very good compared to
some tailwheel types, so no unnatural actions are needed.

wrote in message
...
On 23/03/2014 15:55, harryagain wrote:
"Nightjar" wrote in message
...
On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
...
I have never flown an aircraft in which side-slipping was recommended
for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

It was never intended/designed to use it towing gliders.
Lots of take offs and landings/descents from around 3000'.
Our grouse was that the front cylinders wore out before the rear.
Even though the air is ducted.


Interesting - I've towed with a Pawnee 235 and, once the post-release 10
seconds had been dealt with (and the CHT was below 200, I think) then
there was no need or recommendation to do anything other than fly it. I
can't recall the descent power settings or speed but the aim, as with all
towing, was to get back ASAP while controlling the rate of cooling with
power/speed, going no faster than Va (a bit of loading helps) and keeping
eyes out. The ROD was "adequate" without sideslip.

The view in the landing attitude was unusual, but very good compared to
some tailwheel types, so no unnatural actions are needed.

If you close the throttle and dive at the ground after glider release (as
some of our nutters did), the barrels are overcooled. The pistons of course
are at their hottest as the tow has been at full throttle.
So the piston/barrels clearances are reduced. I heard of one siezed up,
apparently it had a recent overhaul and clearances were already small.
Worst effect is in cold weather ofcourse.

There is no means of controlling the air.
So either sideslipping or a more gradual descent reduces engine wear.
It was apparently even worse years ago when oils were less good.
So we are talking about sideslipping all the way down, nothing to do with
the landing.

Cylinder head temperature is no guide, it lags far behind what is actually
going on.

Gliding clubs are full of nutters as I expect you know.
It was nomal at our place for the tug to find a thermal and circle in it
with the glider on tow.
When the glider released, some tug pilots rolled into a vertical bank wich
became a near vertical dive. At least intiially.

On 24/03/2014 16:14, harryagain wrote:
wrote in message
...
On 23/03/2014 15:55, harryagain wrote:
"Nightjar" wrote in message
...
On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
...
I have never flown an aircraft in which side-slipping was recommended
for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

It was never intended/designed to use it towing gliders.
Lots of take offs and landings/descents from around 3000'.
Our grouse was that the front cylinders wore out before the rear.
Even though the air is ducted.


Interesting - I've towed with a Pawnee 235 and, once the post-release 10
seconds had been dealt with (and the CHT was below 200, I think) then
there was no need or recommendation to do anything other than fly it. I
can't recall the descent power settings or speed but the aim, as with all
towing, was to get back ASAP while controlling the rate of cooling with
power/speed, going no faster than Va (a bit of loading helps) and keeping
eyes out. The ROD was "adequate" without sideslip.

The view in the landing attitude was unusual, but very good compared to
some tailwheel types, so no unnatural actions are needed.

If you close the throttle and dive at the ground after glider release (as
some of our nutters did), the barrels are overcooled. The pistons of course
are at their hottest as the tow has been at full throttle.
So the piston/barrels clearances are reduced. I heard of one siezed up,
apparently it had a recent overhaul and clearances were already small.
Worst effect is in cold weather ofcourse.

There is no means of controlling the air.
So either sideslipping or a more gradual descent reduces engine wear.
It was apparently even worse years ago when oils were less good.
So we are talking about sideslipping all the way down, nothing to do with
the landing.

Cylinder head temperature is no guide, it lags far behind what is actually
going on.

Gliding clubs are full of nutters as I expect you know.
It was nomal at our place for the tug to find a thermal and circle in it
with the glider on tow.
When the glider released, some tug pilots rolled into a vertical bank wich
became a near vertical dive. At least intiially.


Sorry, there are several incorrect assertions in your reply but I'm not
going to continue the discussion. My statements have been based on
considerable personal experience and engineering knowledge, rather than
hearsay and bar talk.

On 22/03/2014 12:28, The Natural Philosopher wrote:
On 22/03/14 12:08, Part Timer wrote:
On 18/03/2014 09:46, Nightjar wrote:
On 18/03/2014 09:02, harryagain wrote:

http://www.youtube.com/embed/Y0XbqHU...yer_detailpage

Heh. I knew these were used on aircraft but not in cars.


A good power to weight ratio, which the rotary engine has because it
needs no additional flywheel, would have been just as important in an
early motor car as it was in early aircraft.

Colin Bignell

I'd have called it a radial engine, not a rotary (Wankel).
No
Radial is engines arranged with cylinders in a circle.
Rotary is when the 'crankshaft' is fixed and the cylinders go round it.

Not needing a flywheel is the least of issues for aircraft - the
propellor itself is a massive flywheel.

It was all about cooling really.

Rotary engines are pigs to get the fuel into. too.

"Another factor in the demise of the rotary was the fundamentally
inefficient use of fuel and lubricating oil, caused in part by the need
to aspirate the fuel/air mixture through the hollow crankshaft and
crankcase, as in a two-stroke engine."

http://en.wikipedia.org/wiki/Rotary_engine

The Wankel 'rotary' is a completely different animal.
It has a rotating piston, not a rotating cylinder.

Radial engines reached their peak at the end of WWII and were then
overtaken but the jet engine and turboprops.

Rotary engines didnt even make it to the end of WWI..

Post WWI Bristol engines went down the radial route and Rolls Royce down
the inline route.

There were legals reasons for this.

In the US Pratt and Whitney were the big radial engine people.

As far as cars went, the cooling problems meant that water cooled was
practically de rigeur as power levels went up. So inline was easily
possible.

The thing about radials being that they offer better air cooling if the
flat face of the cylinders in=s in a prop blast.

But that is draggy - its better to have an inline arrangement and put
the radiators elsewhere where they can be more aerodynamic

Thanks for that info - I appreciated reading it! I wonder what the power
and torque curves are like on a rotary like this? Can't be very
free-revving in a car can it?

wrote in message
...
On 24/03/2014 16:14, harryagain wrote:
wrote in message
...
On 23/03/2014 15:55, harryagain wrote:
"Nightjar" wrote in message
...
On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
...
I have never flown an aircraft in which side-slipping was
recommended
for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

It was never intended/designed to use it towing gliders.
Lots of take offs and landings/descents from around 3000'.
Our grouse was that the front cylinders wore out before the rear.
Even though the air is ducted.


Interesting - I've towed with a Pawnee 235 and, once the post-release 10
seconds had been dealt with (and the CHT was below 200, I think) then
there was no need or recommendation to do anything other than fly it. I
can't recall the descent power settings or speed but the aim, as with
all
towing, was to get back ASAP while controlling the rate of cooling with
power/speed, going no faster than Va (a bit of loading helps) and
keeping
eyes out. The ROD was "adequate" without sideslip.

The view in the landing attitude was unusual, but very good compared to
some tailwheel types, so no unnatural actions are needed.

If you close the throttle and dive at the ground after glider release (as
some of our nutters did), the barrels are overcooled. The pistons of
course
are at their hottest as the tow has been at full throttle.
So the piston/barrels clearances are reduced. I heard of one siezed up,
apparently it had a recent overhaul and clearances were already small.
Worst effect is in cold weather ofcourse.

There is no means of controlling the air.
So either sideslipping or a more gradual descent reduces engine wear.
It was apparently even worse years ago when oils were less good.
So we are talking about sideslipping all the way down, nothing to do with
the landing.

Cylinder head temperature is no guide, it lags far behind what is
actually
going on.

Gliding clubs are full of nutters as I expect you know.
It was nomal at our place for the tug to find a thermal and circle in it
with the glider on tow.
When the glider released, some tug pilots rolled into a vertical bank
wich
became a near vertical dive. At least intiially.


Sorry, there are several incorrect assertions in your reply but I'm not
going to continue the discussion. My statements have been based on
considerable personal experience and engineering knowledge, rather than
hearsay and bar talk.


Just stuff you haven't heard of.

On 25/03/2014 06:49, harryagain wrote:
wrote in message
...
On 24/03/2014 16:14, harryagain wrote:
wrote in message
...
On 23/03/2014 15:55, harryagain wrote:
"Nightjar" wrote in message
...
On 23/03/2014 06:34, harryagain wrote:
wrote in message
...
...
I have never flown an aircraft in which side-slipping was
recommended
for
cooling - what type are you thinking of?


Pawnee ex-crop duster, used for glider towing.
This was the manufacturers advice.


It isn't in the owner's manual.

Colin Bignell

It was never intended/designed to use it towing gliders.
Lots of take offs and landings/descents from around 3000'.
Our grouse was that the front cylinders wore out before the rear.
Even though the air is ducted.


Interesting - I've towed with a Pawnee 235 and, once the post-release 10
seconds had been dealt with (and the CHT was below 200, I think) then
there was no need or recommendation to do anything other than fly it. I
can't recall the descent power settings or speed but the aim, as with
all
towing, was to get back ASAP while controlling the rate of cooling with
power/speed, going no faster than Va (a bit of loading helps) and
keeping
eyes out. The ROD was "adequate" without sideslip.

The view in the landing attitude was unusual, but very good compared to
some tailwheel types, so no unnatural actions are needed.

If you close the throttle and dive at the ground after glider release (as
some of our nutters did), the barrels are overcooled. The pistons of
course
are at their hottest as the tow has been at full throttle.
So the piston/barrels clearances are reduced. I heard of one siezed up,
apparently it had a recent overhaul and clearances were already small.
Worst effect is in cold weather ofcourse.

There is no means of controlling the air.
So either sideslipping or a more gradual descent reduces engine wear.
It was apparently even worse years ago when oils were less good.
So we are talking about sideslipping all the way down, nothing to do with
the landing.

Cylinder head temperature is no guide, it lags far behind what is
actually
going on.

Gliding clubs are full of nutters as I expect you know.
It was nomal at our place for the tug to find a thermal and circle in it
with the glider on tow.
When the glider released, some tug pilots rolled into a vertical bank
wich
became a near vertical dive. At least intiially.


Sorry, there are several incorrect assertions in your reply but I'm not
going to continue the discussion. My statements have been based on
considerable personal experience and engineering knowledge, rather than
hearsay and bar talk.


Just stuff you haven't heard of.


Aaargh, I really shouldn't bite but ...

Despite several thousand flying hours in hundreds of aircraft types and
a range of flying operations (including 1000+ tows) there is no doubt
that there are many things that I have not heard of. An unfortunate
aspect of life is that we don't know what we don't know! The aviation
experience is coupled with Engineering Degrees and Fellowship of
professional bodies so there are (probably) less unknown unknowns than
usual and I suspect that, in this particular case, mine really is bigger
than yours ;-)
But now, I'm going to stop waving mine so pease do the same.

Back to DIY, and no more responses from me on this topic!!

wrote:

An unfortunate aspect of life is that
we don't know what we don't know!

YAdonaldrumsfeldAICM£5

On Tue, 25 Mar 2014 11:58:01 +0000, Biggles wrote:

Interesting - I've towed with a Pawnee 235 and, once the
post-release 10 seconds had been dealt with (and the CHT was below
200, I think) then there was no need or recommendation to do
anything other than fly it. I can't recall the descent power
settings or speed but the aim, as with all towing, was to get back
ASAP while controlling the rate of cooling with power/speed, going
no faster than Va (a bit of loading helps) and keeping eyes out. The
ROD was "adequate" without sideslip.

If you close the throttle and dive at the ground after glider release
(as some of our nutters did)

It was nomal at our place for the tug to find a thermal and circle in
it with the glider on tow.
When the glider released, some tug pilots rolled into a vertical bank
wich became a near vertical dive. At least intiially.

Sorry, there are several incorrect assertions in your reply but I'm
not going to continue the discussion. My statements have been based on
considerable personal experience and engineering knowledge, rather
than hearsay and bar talk.

Just stuff you haven't heard of.

Aaargh, I really shouldn't bite but ...

It's Harry... No more really need be said.

Although, having said that, his long spiel and yours didn't really seem
to contradict each other. You basically said there wasn't a problem if it
was flown by the book. He basically said that it had been a problem if
you ignored the book and flew like a ****.

"****tishness breaks things". Woo. Hold the front page.

On 25/03/2014 11:58, wrote:
....
Aaargh, I really shouldn't bite but ...

Welcome to Harry's world, in which, no matter the weight of opinion
against him, he will never admit he is wrong, even though he usually is.
If you overwhelm him with incontrovertible facts, he will ignore them
and start insulting your intelligence.

Colin Bignell