Subject: Re: Radial engines in Automobiles

From: [email-masked]
Date: 4 Dec 1996 16:54:47 GMT

> Can someone enlighten me here? I know rotary engines (as defined
>above) were used on some early aircraft, by why? Surely everything
>gets hideously complex, with the engine rotating about a fixed shaft.
>Why did they ever do it that way?

Cooling. The rotating cylinders provide a great method to cool the hot
cylinders. Water cooling is a lot heavier, and very ureliable at the time.
Also elininates the need of a flywheel (the rotating engine is the
flywheel).

---

From: [email-masked] (James Wilkins)
Date: Wed, 04 Dec 1996 14:05:06 -0400

> Why did they ever do it that way?

I think the reason was that they didn't overheat while sitting on the
ground running and waiting for everyone else in the squadron to get going.
WWII radials needed an elaborate cowl flap system to control cooling air
flow. 

Rotary engines weren't necessarily as complicated as radials. The cam for
the valves is in the rear, part of the stationary engine mount. The ones I
have seen or have drawings of only have 1 large valve in the head, opening
right out into the breeze, and either a check-type valve in the piston or
transfer ports like a 2-stroke. Some of the intake air comes into the
crankcase through the hollow engine mount where a spray nozzle simply
saturates it with gasoline vapor. This non-explosive mixture is sucked
into the cylinder during part of the intake stroke, then the cam opens the
valve in the head to let in more air and get the mixture lean enough to
burn. The valve in the head opens again for the exhaust stroke. 

So only the cylinders, spark plugs, piston and valve assemblies spin.
There are no cylinder head intake or exhaust manifolds or even a
carburetor. The piston valve was a serious maintenance problem. 

The gas flow through the spray nozzle can be throttled a little, but to
cut back for landing the pilot has to flip the ignition on and off. 

The engine was lubricated with castor oil mixed with the gas. Unburned oil
sprayed out the exposed exhaust valves and coated everything behind
including the pilot.

-- 
James Wilkins
The Mitre Corp.
Bedford, MA

---

From: Rick Cook <[email-masked]>
Date: 5 Dec 1996 05:02:25 GMT

>Why did they ever do it that way?
Cooling. The lubricants of the time were lousy. Spinning the cylinders was
an 'elegant' solution.

--RC

---

From: [email-masked] (James Wilkins)
Date: Thu, 05 Dec 1996 10:00:05 -0400

In article <[email-masked]>, [email-masked]

> burn. The valve in the head opens again for the exhaust stroke. 

I went digging through a 1922 aircraft engine book last night and found
some changes to the above, which is for a 100 HP Gnome Monosoupape (single
valve).
 
Apparently a great advantage was nearly perfect balance. Both pistons and
cylinders spin in circles which are fixed relative to the airplane. Only
the valve assemblies vibrate.  

The cams were in front, the distributor ring and magneto were in back. 
The valve opened half way through the power stroke, stayed open through
the exaust stroke, and closed after 3/4 of the following intake stroke. 
The transfer ports were open 20 degrees before and after bottom dead center. 

The pressing need for more power later in the war made these engines more
complicated and they acquired overhead intake valves and manifolds running
up from the crankcase. Some even had the cylinders spinning one way and
the crank spinning the other.

Lindsay's reprint of the 1977 Model Engineer has an article (no prints) on
building a 1/5 scale working model of the Monosoupape engine. 

>From  Eddie Rickenbacker's bio:
American aviation cadets going to France to fight the Germans arrived at a
training field run by Rickenbacker, Wiedenbach, Spaatz, Tittel, und
Spiegel.

-- 
James Wilkins
The Mitre Corp.
Bedford, MA

---

From: [email-masked] (Bob DeMers)
Date: 5 Dec 1996 09:23:05 CST

> sprayed out the exposed exhaust valves and coated everything behind

In some storie's, the pilot's bowels were also well lubricated, resulting
in a raging case of diarrhea.
-- 
Bob DeMers
Honeywell Technology Center
[email-masked]

---

From: [email-masked] (Roger Grady)
Date: Thu, 05 Dec 1996 23:00:05 GMT

>Cooling. The lubricants of the time were lousy. Spinning the cylinders was

As were the carburetors. Wasn't it the Gnome rotary that had no
throttle control? The pilot reduced power for landing by switching the
ignition on and off.

Roger Grady

---

From: [email-masked] ("Paul C. Dickie")
Date: Fri, 06 Dec 96 05:07:00 GMT

>the valve assemblies vibrate.  

However, a not inconsiderable disadvantage was that the rotating cylinders, 
etc, tended to act as a gyroscope; I understand that the precession when 
turning the aeroplane made flying the thing rather *interesting*...o-)

-- 
< Paul >

---

From: [email-masked] (Steve Rayner)
Date: Fri, 6 Dec 1996 09:03:01 GMT

>Cooling. The lubricants of the time were lousy. Spinning the cylinders was

The engines used degummed castor oil, which is pretty good oil!  The real 
problem was poor heat transfer in the nickel alloy cylinders, fins that 
were too shallow, and low air speeds.  The cylinder heads were machined 
into the cylinder.  Oil coolers, and aluminum alloy heads helped cure 
these problems.
-- 
Steve. 

******************Knowledge is wasted if it is not shared.*******************

---

From: Rick Cook <[email-masked]>
Date: 7 Dec 1996 00:25:44 GMT

>in a raging case of diarrhea.
I have it on competent medical authority (my doctor was an old plane buff)
that this is indeed the case. Further, he told me that the castor fumes are
much more effective than castor oil.

Lotrimil not having been invented, the best remedy the pilots had was
blackberry brandy, which he said countered the effects of the castor fumes
to some extent. As a result, most pilots swigged the stuff constantly when
flying.

This would explain a great deal about WWI in the air.

BTW: An effect of rotary engines which has not been mentioned is what
happened when you tried to make a turn. The combination of a large rotating
mass and light airframes made the gryoscopic effects considerable. Most
planes with rotary engines could turn on a dime in one direction and were
slow to turn in the other. They also had a nasty tendency to spin.

--RC

---

From: [email-masked] (Andrew Morrison)
Date: Mon, 09 Dec 1996 09:15:18 -0800

I saw an aircraft air cooled radial engine lying in the back of a Chevvy
van at the drags in Pennsylvania in 1957. It didn't do very well.

Andy

In article <01bbdf99$aa566680$e738f2cd@cmx00100>, "Joseph Sossi"
<[email-masked]> wrote:

> In response to installing Radial engines in cars it has been tried years
> ago, in 1894 & 1925. The one in 1894 was called the Balzer and it was a 3
> cyl radial, and in 1925 there was a car called the Julian, and it was
> powered by a six cyl air cooled radial with a bore of 3 3/8" x 5"stroke
> that produced 60 hp. the engine was mounted in the rear horizontally. Seems
> like every thing has been tried before some time in history, will attach a
> pic of the engine of the Julian.
> 
> Bye Joe
> begin 600 Radial Engine.JPG

---

From: [email-masked]
Date: Mon, 09 Dec 1996 22:50:20 GMT

>Also elininates the need of a flywheel (the rotating engine is the

 Many thanks every one. One further question: I understand these were
4-cycle engines, not 2-cycle. Given this, how was the valvegear
worked? I have seen references to it's being operated by a cam-ring
fixed to the engine mounting. But such a cam must "rotate" (with
respect to the cylinders) at the same speed as the crank, whereas a
4-cycle engine normally rotates its cams at half the crank speed. What
have I missed here?

--  Dave Brooks    <http://www.iinet.net.au/~daveb>
PGP public key via <http://www.iinet.net.au/~daveb/crypto.html>, or servers
    "From" line rigged to foil spambots: daveb <at> iinet.net.au

---

From: [email-masked]
Date: 10 Dec 1996 22:40:23 GMT

>    "From" line rigged to foil spambots: daveb <at> iinet.net.au

Rotary engines like the Gnome and the Le Rhone were, I belive, 2 strokes.
That accounts, in part, for their high power/weight ratio.  If you see one
up close, it has *huge* exhaust valves, which are basically the entire top
of the cylinder head.  These are operated via pushrod from the crankcase,
which I suspect has a large diameter multi-lobe cam mounted stationary.

The intake is thru the crankcase, and probably a transfer port of some
kind.  The fuel was mixed with castor oil for lube.  I have seen these
engines run at the Rhinebeck aerodrome in Poughkeepsie, NY, and they
are started by priming them up real rich, and when they fire, a *huge*
cloud of castor oil smoke engulfs the spectators who are sitting 
nearby.  Occasionally the inside of the cowling catches on fire, so 
there is always a fire extinguisher standing by.  They cannot be 
throttled, so either the engine is blipped, or there is a switch 
for shorting out a certain number of plugs.

The castor oil is said to have had a "pronounced laxative effect,"
and the pilots supposedly counteracted this with an on-board
supply of blackberry brandy.  

Seeing one of these machines up close makes one realize just how
crazy the pilots were (are) who flew (fly) them.  The engines look
like they are good for about 10 hours before failure, and the failure
is likely to be catastrophic, indeed.  Materials really have come 
a long way.

Jim

---

From: [email-masked] (Peter Brooks)
Date: 6 Dec 1996 18:59:24 GMT

(Dave Brooks) [email-masked] wrote:
: >
:  Can someone enlighten me here? I know rotary engines (as defined
: above) were used on some early aircraft, by why? Surely everything
: gets hideously complex, with the engine rotating about a fixed shaft.
: Why did they ever do it that way?

I'm not 100% sure, myself, but here's a shot at a guess.  Actually,
looking at cross sections, the rotary engine isn't more complex than
the radial, and with some (I think the gnome fits) the intake valve
is vacuum driven, so you don't have a push rod, thus the engine
gets even simpler.

One possible advantage for the rotary is in the induction system.  
I picked up _The lore of flught_ from the discount section at Barnes and
Noble, and that book has the cross sections.  The gnome has a pretty
involved induction system, with the carb located somewhat *behind* the
firewall.  The same engine uses a hollow crank shaft to duct gasses.

More advanced engines, like the Wright J-5 radial, put the carb where
God and Pratt and Whitney wanted it to be, right behind the engine.  However,
this means that there's a rather large blower in the rear crankcase to
distribute the fuel-air mixture.  Note that this is *not* a supercharger,
just a system to keep the fuel from settling out.

BTW, does anybody have any tolerable drawings of the Manley radial engine
that was designed for the (Langston?) flight attempts just before the
Wright brothers succeeded?  It's supposed to be 20 years advanced, but all
I have is a snippet.

: --  Dave Brooks    <http://www.iinet.net.au/~daveb>
: PGP public key via <http://www.iinet.net.au/~daveb/crypto.html>, or servers
:     "From" line rigged to foil spambots: daveb <at> iinet.net.au

Nice 'from line'.  Does it work?  I'm getting tired of EarthStar.com...

Pete Brooks

---

From: [email-masked]
Date: Fri, 06 Dec 1996 23:37:28 GMT

>: Why did they ever do it that way?
 Many thanks, everyone, for the enlightening replies. Consensus seems
to be that the main reason was better cooling, with the poor-quality
lubrication available then.

>Nice 'from line'.  Does it work?  I'm getting tired of EarthStar.com...
 It seems to. The DSI (daily spam index -tm :) has reduced
significantly since I did this, although it's not yet to zero.

---

From: "John R. Johnson" <[email-masked]>
Date: Fri, 6 Dec 1996 15:02:23 -0600

> throttle control? The pilot reduced power for landing by switching the
Actually, the carburetors were not all that bad.  It was just that the
Gnome didn't have one!  Fuel was sprayed into the crankcase in a way
overrich mixture.  For the first two thirds of the intake stroke the
single valve in the head, which was used for both exhaust and intake,
was still open drawing in plain air.  Then the valve closed for the last
third of the intake travel creating a partial vacuum in the cylinder.
In the early Gnomes there was an inertial valve in the center of the
piston that opened at bottom dead center and let rich mixture into the
cylinder where it was diluted in the air already drawn in.  The later
Gnomes merely had a transfer passage that was uncovered near the bottom
of the stroke.  Then at the top of the compression stroke ( about 5 to
1 compression ) the spark plug passed by the magneto and fired!
Just before the bottom of the power stroke the valve in the cylinder
head opened and let the gasses start outward so they wouldn't contaminate
the mixture in the crankcase.

They used castor oil for lubricant so the fuel in the crankcase wouldn't
wash the oil away.  

The engine didn't have a power peak in the normal sense.  The torque 
peak was high enough that the power just kept increasing with RPM up
to about 1000 RPM.  After that the cooling drag increased at the same
rate as the power up to about 1500 rpm so the net power output just
stopped increasing.  

You couldn't throttle them because the crankcase was always full of an
explosive mixture!  As a result the used the "coupe" button which 
grounded the magneto for speed control.  This caused the engine to
blip in and out.  The large rotating mass ensured the engine would
restart immediately when the shorting button was released.

In all of the early WWI movies they had recorded a Thomas Morse Scout
landing, which used the rotary engine.  The director liked the bruup
bruup bruup sound so well that they dubbed the intermittent sound of
the Gnome Rotary at partial power onto the later OX-5's and Hisso's.
It is strange to see a Witchita Fokker ( Elephant ear Travelaire ) 
pretending to be a Mercedes powered Fokker, but actually powered with
a Hispano-Suiza V-8 sounding like a little Gnome Rotary being killed!

The castor oil lubrication was an open loop system and the rotating
engine sprayed a dense cloud of castor oil into the air behind the
engine.  The WWI fighter pilots spent hours inside that cloud with
predictable regularity problems.  Someone spread the rumor that large
quantities of premium French Cognac would counteract the internal
lubricity of the castor oil, so the pilots imbibed large quantities
of cognac.  This was not so much to get well oiled, as to prevent 
being too well oiled! :)

John

---

From: [email-masked]
Date: Thu, 12 Dec 1996 14:31:10 -0600

The strain of not contribuitng to this thread has finally 
become too much:

In article <[email-masked]>,
  "David Langlois" <[email-masked]> wrote:

> In the airplane museum here in Ottawa are cut-away examples of the two
> types of radial engines (fixed cylinders, and rotating cylinders).

Speaking of museums:  No reader of this NG should pass through Pheonix 
without stopping in at the Flying Aces Museum (? or something just like that ?) 
at Falcon field (airport) in Mesa, AZ ( a 'burb of Pheonix). I visited several
years back, and If I don't accidently go to Pheonix soon, I will make a special
pilgramage to see it again. Here' why:

Amongst other treasures they had a P&W R-4360 (_two_ actually, but one is 
hidden under the cowl of a "very limited production" Corsair).
For the non-airheads, thats a 4360 CID, supercharged, 28 cyl. radial 
(4 banks of 7)I forget the HP, rating, but 3,500 HP seems familier.
A discussed-to-death-in-this-thread Gnome rotary is in good view on 
an uncowled WW1 vintage (? was it a Spad maybe ?) fighter, and there 
was an  Allison only a few feet from the "do not cross" ropes.  

There are two hangers _full_ of aircraft, one WWII, and the other WWI. 
Highlights for me were a Spitfire, FW-190, the above mentioned 
Corsair-on-steroids, the ornothopter-looking Taub (WW1 german design approach),
P-51, and a P-38.  All A/C are maintained in sound mechanical, and pristine 
cosmetic condition, and many, I understand, are even flown on (VERY) rare 
occasions.  They all have REAL engines dripping REAL oil! Must be a sign of 
my sickness, but no centrefold comes even close to the sex appeal of these 
machines.

Finally, as if the aircraft weren't enough, there is a BIG bank-type vault (open 
during viewing hours) stuffed to the gills with machine-guns.  
(don't tell Mr. Clinton!) Every type you've ever heard of, and many you haven't
(prototypes, etc.) is represented.  Each has accompanying information which has
NOT been edited for the layman.(is it just me that hates "dumbed down" 
explainations?).  None of the guns I saw hd been cut, welded, or otherwise 
ruined.

Oh, yes..they have biographys and memorabilia from all pilots (all countries 
represented) who ever earned the title of "Ace". Hence the name of the museum.
I bet this stuff would be interesting if it stood alone, but who could tell 
with all those neat machines in the next rooms?

Anyway, that's my vote for the planet's best museum.(non-US flamers note, I HAVE
seen some extent of the planet) Off-topic, I suppose, but I'm guessing this museum's 
collection will appeal to the interests (if not the erotic fantasies) of anyone
who reads this NG.  Arning, if you take your wife with you, one of you will 
probably be unhappy when you leave. ( which of you depends on if it is sooner, 
or later)

ciao, Kevin.

-------------------==== Posted via Deja News ====-----------------------
      http://www.dejanews.com/     Search, Read, Post to Usenet

---

From: [email-masked]
Date: 13 Dec 1996 16:39:56 GMT

In article <[email-masked]>, [email-masked] writes:

>Anyway, that's my vote for the planet's best museum.(non-US flamers note,
I
>HAVE
>seen some extent of the planet) Off-topic, I suppose, but I'm guessing
this
>museum's 

Thank you, thank you, thank you, but my wife is nuttier about these things
than I am. We may have to stay there a week and see who quits first. <g>

Peter

---

From: [email-masked] (Geoffrey Brown)
Date: 13 Dec 1996 13:04:35 GMT

The Curtiss Museum in Hammondsport NY has a large collection of aircraft
engines on display -- going back to ~1910.  I first was tipped off to
this when I noticed many of the photographs in a book on aircraft piston
engines were credited to the Curtiss Museum.  The
collection includes rotaries and radials
(The science musuem
in London has even more, but I found these hard to examine because of the 
display).

Geoffrey Brown

In article <[email-masked]>, [email-masked] says...