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OT: Radial Aircraft Engine Cutaway Pics

Joined
Nov 19, 2007
Location
marysville ohio
Dirt drivers must be better trained, they know to turn off the fuel and let the engine run it out before turning off the sparks. You guys and yer fancy starters and fancy gearboxes and fancy clutches ... :D

It would happen on a hot day when the tank was full before the race. With a bit of heat you could get a fair bit of pressure in the fuel cell, the mechanic turns on the fuel valve and fuel could get past the barrel valve and drip into the engine through the injectors. Best practice is don't take a chance on blowing it up before the race starts.
 
Continental also made radials, I had a W670 from a school auction that was going to go on the front of the van one day ... but luckily, never did It finally got the fan taken off (was used in some sort of tracked vehicle ?) and went back into a home-built aircraft.

670 "tank motors" used to be pretty common. My mechanic had one in the back of his shop. Seems like it was a rather heavy object, for the HP? But probably relentless torque. Sometime in the late 30's they were in most US light tanks. Then the war came along and, IIRC, the government got Continental to also build Wright Whirlwinds (975Cu in?) under license, for a raft of larger tanks, including the famous Sherman. Most Continental radials of all types were used in tanks, not airplanes. But a few flew in civilian models before the war.

That would have made a neat van. Not so much on the gas mileage, i imagine. :)
There's a VW beetle with a big radial in the back, among many other vehicles including a motorcycle or 2. (not the originals like megola, these are more recent "fun/hold my beer and watch this" type projects) around the world.

smt
 
Joined
Nov 19, 2007
Location
marysville ohio
Mechanic ! Whoa, you guys be deluxe ! we make the driver turn on the ign first, then the fuel, after the wheels are turning. That way all we have to worry about is the drunk redneck driving the push truck :)

Well we had to screw around with warm up, don't forget to change out the warm up plugs! Pre race "festivities", TV, Air Force flyover, gentlemen start your engines and any other BS the promoter could think up. Plenty of time for a little hydraulic event to occur.
 

DDoug

Diamond
Joined
Oct 18, 2005
Location
NW Pa
670 "tank motors" used to be pretty common. My mechanic had one in the back of his shop. Seems like it was a rather heavy object, for the HP? But probably relentless torque. Sometime in the late 30's they were in most US light tanks. Then the war came along and, IIRC, the government got Continental to also build Wright Whirlwinds (975Cu in?) under license, for a raft of larger tanks, including the famous Sherman. Most Continental radials of all types were used in tanks, not airplanes. But a few flew in civilian models before the war.


smt

Also used here......:
Helicopter Sikorsky S-55 / H-19 general technical description - Heli Archive
 

Cyclotronguy

Stainless
Joined
Sep 21, 2005
Location
Northern California
Newman109

Not too far from you is UC Davis and just west of town Medlock Field (Air Nav 69CL ie the university airport)

In my very distant past I was the off hours / weekend manager of that facility. No idea what the office looks like now but at the time we had a sectioned, electrically powered and lit Wright Cyclone on a disply stand in the seating area.

Push the button, watch it turn, As it turned the exposed spark plugs would illuminate, poppets would open and close. and etc.

At the North East edge of the field contigious with the Constant Acceleration Lab was one of the Project Gemini capsule mock-ups, of which I was told there were 4 or 5 in total. OF those the one on the UC Campus was on loan from Moffett Field
 

GregSY

Diamond
Joined
Jan 1, 2005
Location
Houston
Re: Hydraulicking.....when those IROC* Camaros first came out...whatever year that was....they had some sort of cowl induction hood that would feed fresh air into the engine, allowing it to reach in excess of 180HP. In any case, the hood had provisions to allow rain water to drain off before reaching the intake tract of the engine. That is....as long as you parked on flat ground or with the nose down. But it came to bear that if you parked on an incline with the nose of the car up a little, the water would indeed run into the engine. It would find an open intake valve, and fill the cylinder with enough water that when Guido* came out in the morning and hit the starter, it would bend the connecting rod something fierce. Time for a hood redesign.


*I was living in Chicago back then, and the joke was IROC stood for Italian Retard Out Cruising.....hence my use of Guido.
 

Yan Wo

Hot Rolled
Joined
Jan 22, 2014
Location
South Jordan, Utah, USA
I saw my first cut-away radial engine about 65 years ago. I loved it. It was turning slowly and I could see exactly how it worked. A complete mystery before that.

Fast forward about 60 years and I'm with my nephew Steve at a fly-in. Many of the hangars had displays, one of which was a radial engine cut-away. As we walked to the next hangar I explained why all radial engines have an odd number of cylinders.

Exactly 17 seconds later we entered the next hangar to see a cut-away of one of the few EVEN cylinder radial engines!

Reminds me of the time we were driving east on I-70. I was explaining why you never see gravel spread on new pavement any more. Seventeen seconds later we turned onto US 6 and my brother-in-law silently pointed to a sign at the side of the road: "Caution. Loose gravel next 15 miles."
 

sealark37

Stainless
Joined
Mar 24, 2010
Location
Davidson NC USA
I have sat between a pair of R-2800s for several thousand hours. I had one shut itself down on landing. When the cowl was dropped, two cylinders fell out on the ramp. Those engines ran dry-sump, so even with severe damage, the engine would run until it used up the 10 gallon oil tank.
 

Clive603

Titanium
Joined
Aug 2, 2008
Location
Sussex, England
I saw my first cut-away radial engine about 65 years ago. I loved it. It was turning slowly and I could see exactly how it worked. A complete mystery before that.

Fast forward about 60 years and I'm with my nephew Steve at a fly-in. Many of the hangars had displays, one of which was a radial engine cut-away. As we walked to the next hangar I explained why all radial engines have an odd number of cylinders.

Exactly 17 seconds later we entered the next hangar to see a cut-away of one of the few EVEN cylinder radial engines!

A four stroke radial needs odd numbers of cylinders to give an even firing intervals. It also makes the drum cam system engineering much simpler.

Generally four stroke engines having even numbers of cylinders arranged radially are commonly known as "fan configuration" as there are usually sufficient other differences to make the distinction worthwhile. There were some very odd configurations and arrangements built that seriously beg the question "Why?". Such as irregular angular spacing of the cylinders. Vibration control I presume.

The common radial configuration has certain inherent vibration issues which can be very destructive if appropriate design precautions aren't taken. For many year radial engines were restricted to speeds below the first critical vibration frequency for this reason.

Bristol and Curtiss both built even number cylinder radials. Both had overhead camshaft valve operation so individual drives had to be provided. They designed as multiple V4 engines around a common crankcase, true radials, not fan engines. Theoretically this has considerable advantages in vibration control allowing high speed running. Even firing intervals result from firing cylinders on each bank alternately.

Bristols Hydra was a 16 cylinder two row engine. Running at around 3,700 rpm the prototype produced nearly double the power of the similar size Mercury. As ever with aircraft engines full development was expected to considerably increase power. It worked well enough but suffered vibration problems which would need a crank re-design with a centre main bearing so was abandoned as the sleeve valve motors were clearly going to be a simpler proposition with much more development potential.

bristol-hydra-display.jpg

The Curtis Chieftain used a similar OHC two row design but only 12 cylinders. Similar capacity to the Hydra but less powerful and slower running.

NASM-A19710917000-NASM2014-02810-000001.jpg

Armstrong Siddeley went all in on the multi bank OHC idea with several prototypes and design studies.

Albeit mostly with conventional odd numbers of cylinders per row.

Hyena - 3 rows of 5 cylinders, Terrier - 2 rows of 7 cylinders, Deerhound - 3 rows of 7 cylinders, Wolfhound - 4 rows of 7 cylinders, Boarhound - 4 rows of 6 cylinders, Mastiff 4 rows of 9 cylinders.

Dog Triple-Row Aero-Engines | Armstrong Siddeley.

Despite the issues with practical implementation the concepts must have been considered promising enough for Rolls Royce to apply considerable pressure on the Air Ministry resulting in Armstrong Siddeley not only being told to stop work on such designs in 1941 but also being instructed to hand over all design data and records to Rolls Royce. Who promptly destroyed the lot.

Clive
 
Several of us mentioned Megola.

I've posted this photo a few times in the past.

It was a moderately successful design & lasted long enough to go through several model changes.
Probably until stop signs proliferated, road speeds increased, and people began demanding self-commencers instead of push-start on their motorized vehicles. :)

megolaradial.jpg


smt
 








 
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