Flap Pawl spring

How to keep the Cessna 170 flying and airworthy.

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HMA170
Posts: 10
Joined: Thu Apr 13, 2006 11:32 pm

Flap Pawl spring

Post by HMA170 »

First annual on the 170A. Found that the flap pawl springs are missing on both the right and left side of plane. It appears that this is needed to prevent flaps from moving (gust lock) while in the upright position. My question is this, Have they been removed for a reason or should I replace them both. I use manual gust locks every time I fly between the flaps and ailerons. 170A IPC Page 19, Fig. 11-10 Part # 0523227. If needed, parts location ? Thanks
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bradbrady
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Joined: Wed Jun 01, 2005 11:41 pm

Post by bradbrady »

HMA 170,
Yes you need to install the springs! If their in the IPC they need to be on the A/C :roll: No mater what! To make the A/C legal.
brad
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rupertjl
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Joined: Thu Jun 17, 2004 5:29 pm

Post by rupertjl »

i bought these at Iwantcessnaparts.com...I think they were like $35 a piece from there...which is a little rediculous, but i've come to expect that now.
HMA170
Posts: 10
Joined: Thu Apr 13, 2006 11:32 pm

Post by HMA170 »

Found them on-line for 26.50 each (ouch). I will install them when they arrive. Thanks for the replies. I have learned a lot of great information through this Association. Another proud 170 owner.
prairiechicken
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Joined: Sun Sep 03, 2017 8:38 am

Re: Flap Pawl spring

Post by prairiechicken »

Air Repair cost each as of 2/4/20 is $73.72! Has anyone found a different source?
Ty Richter
1712D
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Bruce Fenstermacher
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Re: Flap Pawl spring

Post by Bruce Fenstermacher »

BTW the pawl only assists the flap to stay locked in the up position. Any tail wind while the plane is stationary on the ground will overcome the pawl and your flap will slam full on and back to neutral. In a pinch place the flaps full on to hold them or install a gust lock.
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Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
prairiechicken
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Joined: Sun Sep 03, 2017 8:38 am

Re: Flap Pawl spring

Post by prairiechicken »

Thanks Bruce,
Does that make the purpose of the pawl to more for backup if a flap retract spring breaks? I had envisioned the pawl and spring combo to be for keeping the flaps from "flapping" with a tailwind. I learned something today!
Ty Richter
1712D
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MoonlightVFR
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Re: Flap Pawl spring

Post by MoonlightVFR »

What does this part Look LIke?

How can I tell if mine are missing?
gradyb, '54 B N2890C
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ghostflyer
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Re: Flap Pawl spring

Post by ghostflyer »

If it’s the springs that go from the flap to the interior of wing and hold the flaps in the trail position and on the flap stops well mine came from “aero Home Depot “ at the staggering price of 73 cents . I bought 2 of them . That was over 6 years ago and still going strong after many inspections including “SIDS” and flying hours .
prairiechicken
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Re: Flap Pawl spring

Post by prairiechicken »

They are small springs that are attached to the linkage against the fuselage. Only found on the earlier models with hinged flaps.
Ty Richter
1712D
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Bruce Fenstermacher
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Re: Flap Pawl spring

Post by Bruce Fenstermacher »

MoonlightVFR wrote:What does this part Look LIke?

How can I tell if mine are missing?
Grady, yours ARE missing. I can tell from here.

They didn't use this part on the '54 you own. Only the A model. :twisted: :D
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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Bruce Fenstermacher
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Re: Flap Pawl spring

Post by Bruce Fenstermacher »

prairiechicken wrote:Thanks Bruce,
Does that make the purpose of the pawl to more for backup if a flap retract spring breaks? I had envisioned the pawl and spring combo to be for keeping the flaps from "flapping" with a tailwind. I learned something today!
No. With out the spring the flap will not retract to neutral while not in flight. . The spring alone can not hold the flap when a gust from the back hits it. The paw is suppose to hold the flap locked in but on even the best examples it can not overcome a good tail wind gust.

Should your spring break while in flight, your flaps will retract due to air pressure pushing them up as you release the flap handle and there is no longer a cable holding them down.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
prairiechicken
Posts: 32
Joined: Sun Sep 03, 2017 8:38 am

Re: Flap Pawl spring

Post by prairiechicken »

No. With out the spring the flap will not retract to neutral while not in flight. . The spring alone can not hold the flap when a gust from the back hits it. The paw is suppose to hold the flap locked in but on even the best examples it can not overcome a good tail wind.

Yes, I have experienced a tail wind slapping my flaps around while taxiing on a gusty day. I had imagined that the pawl system would help that a little, doesn't sound like it does.
Ty Richter
1712D
tfisher
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Re: Flap Pawl spring

Post by tfisher »

Can anyone post a link do them I need two
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ghostflyer
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Re: Flap Pawl spring

Post by ghostflyer »

Bruce,
I am having trouble following your last entry. I thought it was about the pawl springs in the flap mechanism and not in the tail wheel. I am just confused.
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