Jacobs R-755 Radial

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Colonel
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Poetry in motion!

Remember, all these were designed in the 1920's and 30's
which means no calculators. No computers. Just sliderules!

That counterweight is nuts.


45 / 47 => 95 3/4%
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Liquid_Charlie
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The shakey jake -- never flew one but just know their reputation - I guess I'm really old - I used a slide rule -- haha
"black air has no lift - extra fuel has no weight"
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Colonel
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It's a smaller engine than you would have used in transport aircraft ...

I think the C190/195 used them, as well as a few Stearman, which had
pretty well everything bolted to them over the years.

PS. I learned how to use a slide rule when I was a kid, too. My dad had
several of them. I remember when 4-banger LED calculators came out
for consumer sale in the 70's they were very expensive. Remember those
pricey LED watches?! Given the choice of a used RD 350 or a 4-banger LED
calculator, I would take the RD 350 and a slide rule! Hell of a lot more fun.

The RD 350 might not look like much today, but if you were a teenager in
the 1970's it was amazing and attainable, which is why it became
a legend:

https://en.wikipedia.org/wiki/Yamaha_RD350

My slightly unhinged uncle bought an RZ 350 at quite an advanced age. Him,
not the RZ 350. My slightly unhinged uncle would fly a NORDO cub at night
with a flashlight for landing. I remember one day, he had it on skis, and he
scared the living shit out of the Pride Of Scare Canada™ (who wrecked a Maule
later when he tried to land it). My slightly unhinged uncle took a speedy run
directly at the shore after landing on an icy lake. The Pride of Scare Canada™
nervously asked my slightly unhinged uncle how he was going to stop before
he hit the shore.

"Reverse thrust", my slightly unhinged uncle replied. The Pride of Scare Canada™
thought for a moment and said, "This doesn't have reverse thrust" which was
actually a valid point for a fixed pitch prop aircraft.

"Sure it does", my slightly unhinged uncle replied, shoving the throttle forward
and punching the rudder pedal, rotating the cub on skis 180 degrees and backing
it into a stop at the shore.

As you may surmise, my family of fighter pilots has generationally had a somewhat
tense relationship with pilots that have logged 1000 hours, ten times over as Jake
Mulhall used to put it.

Image

August, 1962. Awesome stick.
45 / 47 => 95 3/4%
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Colonel
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Historical note: I can't believe that they actually used the liquid-cooled V-12
(Spitfire, Hurricane, P-51) on fighters in WWII. A kid with a BB gun could quite
literally take one down, if he poked a hole in the radiator and the coolant leaked
out.

Contrast that with a radial, which could return home with jugs missing.

I know, I know, it has more frontal area. That didn't stop the P-47 from being the
most successful forgotten fighter of WWII. The war in Europe could not have been
won, without it.
Luftwaffe ace Heinz Bär said that the P-47 "could absorb an astounding amount of lead [from shooting at it] and had to be handled very carefully" ... the sturdy airframe and tough radial engine could absorb a lot of damage and still return home.

Despite being the sole remaining P-47 group in the 8th Air Force, the 56th FG remained its top-scoring group in aerial victories throughout the war ... the Thunderbolt ended the war with 3,752 air-to-air kills claimed

The P-47 could perform a dual-function on escort missions as a fighter-bomber ... from D-Day until VE day, Thunderbolt pilots claimed to have destroyed 86,000 railroad cars, 9,000 locomotives, 6,000 armored fighting vehicles, and 68,000 trucks
I'll take a big radial over a girly V-12 any day. Guys with umlaats know what they're talkin' 'bout.
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Chuck Ellsworth
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I love radial engines, probably because more than half of my over thirty thousand ( Accident free. ) hours was on radials.

Just loved flying the P.&W. 985 powered Stearman which was one of the first airplanes I flew commercially sixty years ago crop dusting in Southern Ontario.

Never got to fly the 600 H.P. Stearman but did see them in airshows.

Anyone here fly the 600 H.P. Stearman?
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Colonel
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I found the R-985 450hp Stearman to be pretty nose-heavy.

Image

I cannot imagine the R-1340 in it, and do not ask how that photo was taken.
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Chuck Ellsworth
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There were a few converted to the 600 H.P. engine and I am sure they had to add weight in the tail.

Yes it is a bit on the heavy side control input wise but it is a sexy bitch.

You have not felt heavy controls until you fly the PBY, especially the rudder.

For light controls the Mooney Mite was really light.

Do you get a woody looking at Nancy Pelosi Colonel?
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Liquid_Charlie
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I'll take a big radial over a girly V-12 any day. Guys with umlaats know what they're talkin' 'bout.


ask "Pappy" Boyington

Little bit of a drift but Colonel did you have any insight to what kind of aircraft the CF 5 really was. According to what you read on the internet they were a great and cheap aircraft but I had always got the impression they were not liked that well by the actual pilots.
"black air has no lift - extra fuel has no weight"
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Colonel
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After flying the -104, the Air Force wanted my father to fly it. He left.

It's a light, cheap aircraft. The early versions were underpowered dogs, I was told
by my father's friends that flew them.

The later versions were better - I think they had better engines. Snort used to fly
them in the Aggressor Squadron against F-14's and did not complain.

A friend of mine was an FAIP on the T-37 and T-38 and seemed to like it. The T-38,
not being a FAIP.
Do you get a woody looking at Nancy Pelosi Colonel?
Come on, you know she's got a great rack. And when she takes those dentures out ....
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Nark
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I could tune out AOC in bed.
Twin Beech restoration:
www.barelyaviated.com
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