Cruise Speed Cessna170B

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MoonlightVFR
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Cruise Speed Cessna170B

Post by MoonlightVFR »

Decided to do a simple inquiry to Google

"cruise speed of Cessna 170" - As you know Google Knows some stuff.

Google gave a cruise speed of 121 mph. None of us wants the label of being gullible. I figure my C170B
has a cruise speed avg of 107 mph for trip planning purposes. That is 14 mph slower!

I played around w cruise speed inquiry of several different aircraft.

Still do not quite understand Cirrus 22T speed of 211 mph vs Beechcraft Bonanza 36 speed of 176 mph. A36 has retractable gear and Cirrus is FIXED gear. Cirrus beats the pants off the A36. How could this be?
gradyb, '54 B N2890C
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lowNslow
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Re: Cruise Speed Cessna170B

Post by lowNslow »

Actually that's pretty accurate in my experience. I consistently get 105 knots in cruise (121mph) at 2450 rpm burning about 7.5gph.
Karl
'53 170B N3158B SN:25400
ASW-20BL
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daedaluscan
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Re: Cruise Speed Cessna170B

Post by daedaluscan »

Well I certainly don’t. I have 8.50 x 6.00 tires. I got 97 knots with a cruise prop, 92 with the climb prop.

That’s a 5% reduction so 9 minutes on a three hour trip. I can live with that. 9 minutes more fun!
Charlie

1956 170B C-GDRG #27019
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GAHorn
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Re: Cruise Speed Cessna170B

Post by GAHorn »

It should be evident that the published cruise speeds of any model airplane is based upon a standard day, standard NEW airplane, etc etc. If YOUR result is different....it's because YOUR situation is different.... and also likely different is your non-calibrated 65 year-old instrumentation.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Re: Cruise Speed Cessna170B

Post by Bruce Fenstermacher »

I have found a wide range of speeds a 170 will do. On some of the faster examples its obvious cause the owner has gone above and beyond with every speed trick. Most of the slower examples the exact opposite, the owner has installed speed robbing equipment such as larger tires or climb prop.

But there are examples of 170 that fit neither of the above that go fast or go slow. In some cases it is the tach and or the airspeed indicator. Either of these instruments not spot on fouls up everything. But mostly it is how straight the airframe is or how well it is rigged. These are hard to see or know without very close study of the individual airframe.

I think a 121mph 170, one that easily sees 121mph without higher RPM, is a fast 170. I think most 170s will do between 110 and 115 mph. I consider that speed range normal. Under 108 mph is a slower example of a 170.

My A model will do about 108 mph on average. We do run 7:00 series tires so there is a little penalty. Also the remnants of about 6 antennas can be found about the fuselage besides the actual antennas in use. Otherwise it's drag from here and there due to repairs, use and age.
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GAHorn
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Re: Cruise Speed Cessna170B

Post by GAHorn »

Bruce Fenstermacher wrote:I have found a wide range of speeds a 170 will do. On some of the faster examples its obvious cause the owner has gone above and beyond with every speed trick. Most of the slower examples the exact opposite, the owner has installed speed robbing equipment such as larger tires or climb prop.

But there are examples of 170 that fit neither of the above that go fast or go slow. In some cases it is the tach and or the airspeed indicator. Either of these instruments not spot on fouls up everything. But mostly it is how straight the airframe is or how well it is rigged. These are hard to see or know without very close study of the individual airframe.

I think a 121mph 170, one that easily sees 121mph without higher RPM, is a fast 170. I think most 170s will do between 110 and 115 mph. I consider that speed range normal. Under 108 mph is a slower example of a 170.

My A model will do about 108 mph on average. We do run 7:00 series tires so there is a little penalty. Also the remnants of about 6 antennas can be found about the fuselage besides the actual antennas in use. Otherwise it's drag from here and there due to repairs, use and age.
...and don't forget about that green paint. :twisted:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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ghostflyer
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Re: Cruise Speed Cessna170B

Post by ghostflyer »

And having blue paint ,so much faster than those red ones .
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cessna170bdriver
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Re: Cruise Speed Cessna170B

Post by cessna170bdriver »

Every time I’ve ever figured it, I get 120 mph, maybe couple more if I’m where WOT gives 2600 rpm. That’s with a 76/53 prop, 600-6 tires, and no wheel pants.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
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