What is it?
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From: West Palm Beach,
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Hi John; That is an AERONCA SC, built back in the late '30s. I grew up hanging around the Conway Pa. airport and they had one there. It unfortunately stalled on takeoff one day, trying to clear a nearby hill, and crashed, destroying the plane & killing the two occupants. Lee Robinson W. Palm Beach, FL
#9
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Thought someone else might like to see this web site.
http://www.pilotfriend.com/photo_alb...template42.htm
I'll quit now. I'm just excited. I think this is going to be a cool plane.
John
http://www.pilotfriend.com/photo_alb...template42.htm
I'll quit now. I'm just excited. I think this is going to be a cool plane.
John
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From: Gothenburg, SWEDEN
Try this vintage aircraft photo album. Dozens of Ryan SCW pictures
http://www.russellw.com/photoalbum/default.asp
More great scale projects:
http://yolo.net/~jeaton/gems/gems.htm
/Leo
http://www.russellw.com/photoalbum/default.asp
More great scale projects:
http://yolo.net/~jeaton/gems/gems.htm
/Leo
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Hi guys; GAD! I really screwed that up! It is indeed the Ryan SC. The low wing
AERONCA was similar with the faired gear and the rocker arm bumps on the cowling. Now I can't recall the model designation. It was the one that crashed. I think it had either a LeBlond or Pobjoy of 90 hp. It's been so long ago that my meager memory is fuzzy!! Hey! I've earned some forgetfullness---I hit 80 next March! But I just passed my Class 2 commercial med, and survived my BFR! Lee Robinson W. Palm Beach, FL
AERONCA was similar with the faired gear and the rocker arm bumps on the cowling. Now I can't recall the model designation. It was the one that crashed. I think it had either a LeBlond or Pobjoy of 90 hp. It's been so long ago that my meager memory is fuzzy!! Hey! I've earned some forgetfullness---I hit 80 next March! But I just passed my Class 2 commercial med, and survived my BFR! Lee Robinson W. Palm Beach, FL
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From: West Palm Beach,
FL
That pic of the AERONCA LC is the one, encept this one does not have the bumped cowling the one at Conway had. I wonder what the engine difference was. I was only about 12 at the time & was in the early stages of that malady called "airplane crazy"!! Lee
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From: , NJ
Robinaire - Good for you! I'm just a kid of 74, and I let my Medical lapse (like my memory!).
I hold Comercial SMEL, Inst., and ATP on the B-707, 720, 727, 747, 757, 767, and L-1011.
I hold Comercial SMEL, Inst., and ATP on the B-707, 720, 727, 747, 757, 767, and L-1011.
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From: Mary Esther, Florida, FL
[b]Lee:
Might have been a leBlond, but I'm sure if it had been a Pobjoy you would remember the prop shaft being about half way up the top cylinder - They were all spur geared with the prop shaft a long way off the center of the engine.
Bill.
Might have been a leBlond, but I'm sure if it had been a Pobjoy you would remember the prop shaft being about half way up the top cylinder - They were all spur geared with the prop shaft a long way off the center of the engine.
Bill.
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From: Mary Esther, Florida, FL
[b]This is a side jaunt on this thread, but I've always thought the Pobjoy engines were interesting. Here's front and side views of the Pobjoy "R" engine, 90 hp, approximately 155 cid. Third shot is the internals, that's not a flywheel, it's a harmonic damper on the front of the crank. Finally, an "R" installed in, of all things, a Piper Cub.
Bill.
Bill.
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From: Mary Esther, Florida, FL
[b]John:
Probably the best known installation of the Pobjoy engine was in the Comper "Swift," a shoulder wing single seat open cockpit sport and racing plane. A Brit flew one from England to Australia around 1931 or so, set several records doing it.
Bill.
Probably the best known installation of the Pobjoy engine was in the Comper "Swift," a shoulder wing single seat open cockpit sport and racing plane. A Brit flew one from England to Australia around 1931 or so, set several records doing it.
Bill.
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From: Mary Esther, Florida, FL
[b]If you want a headache, dig into the operation of a sleeve valve engine. Most if not all Bristol radials were sleeve valve, also the Napier "Lion" and "Sabre" engines.
The only American sleeve valve engine that I know of was the Knight "Aero" engine. It was used in the Willys-Knight passenger car.
Bill.
The only American sleeve valve engine that I know of was the Knight "Aero" engine. It was used in the Willys-Knight passenger car.
Bill.
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Bill,
Well since I like researching the improbable and because I have been described as having a convoluted mind, it would only be fitting if I looked at sleeve valve
rotary engines. It would probably fit right in along side the Wankel rotatory engines I thought were going to surpass the V8s in the seventies.
I really liked that Mazda RX4 I had.
John
Well since I like researching the improbable and because I have been described as having a convoluted mind, it would only be fitting if I looked at sleeve valve
rotary engines. It would probably fit right in along side the Wankel rotatory engines I thought were going to surpass the V8s in the seventies.
I really liked that Mazda RX4 I had.John
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From: Mary Esther, Florida, FL
[b]John:
Did a little looking myself, discovered an oddity.
The [link=http://restored-classics.com/willy/page6.html]Knight Aero[/link] used two sleeves in a single cylinder. I have never been into one, I thought it used the single sleeve as did Bristol and Napier. Click the link, there's a good description of the two sleeve system.
[link=http://www-g.eng.cam.ac.uk/125/achievements/ricardo/page36.htm]Here's[/link] a single sleeve single cylinder development engine. No details, just a picture. The caption is interesting though.
[link=http://www.geocities.com/kiwiengineer2002/sleeve.html]Here[/link] is a good explanation of the single sleeve engine, with diagrams. A bit hard to get through uless you already are familiar with this design, but give it some study and you'll get it.
Bill.
Did a little looking myself, discovered an oddity.
The [link=http://restored-classics.com/willy/page6.html]Knight Aero[/link] used two sleeves in a single cylinder. I have never been into one, I thought it used the single sleeve as did Bristol and Napier. Click the link, there's a good description of the two sleeve system.
[link=http://www-g.eng.cam.ac.uk/125/achievements/ricardo/page36.htm]Here's[/link] a single sleeve single cylinder development engine. No details, just a picture. The caption is interesting though.
[link=http://www.geocities.com/kiwiengineer2002/sleeve.html]Here[/link] is a good explanation of the single sleeve engine, with diagrams. A bit hard to get through uless you already are familiar with this design, but give it some study and you'll get it.
Bill.
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Hmmm... So the 4 stroke RCV90 bears some resemblance to the E25 Sleeve. The difference being in the RCV the sleeve is on a rotary gear and the E25 it is a crank pin and socket. Aren't engines wonderful? You're right they are a strange animal. I can't conceive of the dual sleeve Aero Knight engine as being very practical - heat transfer must have been a bear - and the machining tolerances - ouch, yet it ran and was successful product.
Sometimes we think if something is CNC machined - the tolerances will be better than can be realized by a machinist. So obviously superior is modern technology we forget that the CNC is only following the pattern a programmer taught it. Witness the fact that a skilled machinist 60 years ago held tolerances as good as or better we can hold them today!
John
Sometimes we think if something is CNC machined - the tolerances will be better than can be realized by a machinist. So obviously superior is modern technology we forget that the CNC is only following the pattern a programmer taught it. Witness the fact that a skilled machinist 60 years ago held tolerances as good as or better we can hold them today!
John
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From: Mary Esther, Florida, FL
[b]John:
Tight tolerances? When Roy Cox hit the market with his 049s some 50 years ago he claimed a millionth tolerance. Might have been pushing the truth a little bit, but it was true that any new piston would work in any new cylinder. And this was a plain iron piston and sleeve, no ring to seal it.
Did the sleeve valve study give you a headache? And RCV tried to get a patent on 80 year old technology.
Bill.
Tight tolerances? When Roy Cox hit the market with his 049s some 50 years ago he claimed a millionth tolerance. Might have been pushing the truth a little bit, but it was true that any new piston would work in any new cylinder. And this was a plain iron piston and sleeve, no ring to seal it.
Did the sleeve valve study give you a headache? And RCV tried to get a patent on 80 year old technology.
Bill.
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Bill,
I worked in Automotive. In a lifter the tolerances are grouped into 20 millionths ranges and then selected for the piston to the body during assembly. We thought we were doing good if we kept most of the bodies within 2 ranges. On the body this is an ID grind of roughly 3/8-1/2" X 1/2-3/4" for cars, 5 ranges total 40 pieces a minute.
The key statement is 40 pieces per minute. Production is what has been gained by technology over the years. The other gain has been the ability to use exotic steels and other materials that didn't even exist then. Cast iron machines pretty easily.
Still you can't knock Roy Cox's .049. I know from personal experience that the pistons and cylinders were interchangable. As a boy of 12 we took them apart and swapped parts looking to make the killer motor! Most of them ran with used - well used parts!
John
I worked in Automotive. In a lifter the tolerances are grouped into 20 millionths ranges and then selected for the piston to the body during assembly. We thought we were doing good if we kept most of the bodies within 2 ranges. On the body this is an ID grind of roughly 3/8-1/2" X 1/2-3/4" for cars, 5 ranges total 40 pieces a minute.
The key statement is 40 pieces per minute. Production is what has been gained by technology over the years. The other gain has been the ability to use exotic steels and other materials that didn't even exist then. Cast iron machines pretty easily.
Still you can't knock Roy Cox's .049. I know from personal experience that the pistons and cylinders were interchangable. As a boy of 12 we took them apart and swapped parts looking to make the killer motor! Most of them ran with used - well used parts!

John



