I have my instruments being overhauled and the shop needs the airspeed indicator markings. I don't have them. Its a 1950 170A with the 145.
Anybody have them?
Art
Airspeed Arc markings
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briancbaker
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cessna170bdriver
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I notice that page 8 doesn't specifically state the lower ends of the white and green arcs. If I interpret page 13 correctly, the flaps-down, power-off stall speed is 53 mph (bottom of white arc), and the flaps-up power-off stall speed is 58 mph (bottom of green arc).
Put a white arc from 53 to 100 mph (flap operating range); a green arc from 58 mph to 140 mph (normal operating range), a yellow arc from 140mph to 160 mph (caution range), and a red line at 160 mph (never exceed speed).
This seems to agree with the manual and the most current certification standards: FAR Part 23.1545. In addition, FAR 23.1563 requires a placard stating maneuvering speed (115 mph) although I have seen airspeed indicators with a blue line at this speed. Maneuvering speed isn't mentioned in 23.1545, but I think that as long as your're marking the airspeed indicator anyway, it's a good idea to have a reminder. Anyone who is conscious and breathing on their own should be able to count the number of engines on the 170 and not confuse the blue line for a multi-engine best rate of climb speed with one engine inop. Anyone else feel free to chime in here.
Miles
Put a white arc from 53 to 100 mph (flap operating range); a green arc from 58 mph to 140 mph (normal operating range), a yellow arc from 140mph to 160 mph (caution range), and a red line at 160 mph (never exceed speed).
This seems to agree with the manual and the most current certification standards: FAR Part 23.1545. In addition, FAR 23.1563 requires a placard stating maneuvering speed (115 mph) although I have seen airspeed indicators with a blue line at this speed. Maneuvering speed isn't mentioned in 23.1545, but I think that as long as your're marking the airspeed indicator anyway, it's a good idea to have a reminder. Anyone who is conscious and breathing on their own should be able to count the number of engines on the 170 and not confuse the blue line for a multi-engine best rate of climb speed with one engine inop. Anyone else feel free to chime in here.
Miles
Miles
“I envy no man that knows more than myself, but pity them that know less.”
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“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
Airspeed Arcs
This organization never ceases to amaze me. I want to thank everyone for their helpfulness. I always get a fast response to any question I have.
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Art
What a great bunch!!
Art
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cessna170bdriver
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Re: Airspeed Arcs
Keep the questons coming! I've learned a lot just by researching questions like this. '98C still has her original airspeed indicator, but if I ever want or have to replace it, I can come back here for the markings. The B-model stall speeds may be different by an MPH or two, but the idea is still the same.schefler wrote:This organization never ceases to amaze me. I want to thank everyone for their helpfulness. I always get a fast response to any question I have.
What a great bunch!!
Art
Miles
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne