Flap Positions on 52 170B

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nippaero
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Flap Positions on 52 170B

Post by nippaero »

Working on placards... I've noted that some planes have a 10 degree flap position and some don't. My manual for my 1952 170B doesn't mention a 10 degree setting but my plane has a 10 degree notch. I am wondering if someone added the 10 degree notch at some point. The records do not say anything. Which 170's had the 10 degree flap setting?
1952 170B
N8180A s/n 25032
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gfeher
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Re: Flap Positions on 52 170B

Post by gfeher »

Yes, someone added the 10 degree setting to your plane. The '52 and later models up to SN 26504 were not delivered with the 10 degree setting. But all B models are certified for the 10 degree position and many added the 10 degree notch to the flap ratchet using a drawing available from Cessna. A copy of it is available in the MX Library. My '52 model still has the ratchet in the original condition without the 10 degree notch. I guess I don't know what I'm missing because I don't feel a need to change it.
Gene Feher
Argyle (1C3), NY
'52 170B N2315D s/n 20467 C-145-2
Experimental J3 Cub Copy N7GW O-200
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ghostflyer
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Re: Flap Positions on 52 170B

Post by ghostflyer »

I have the 10 deg flap notch and use it on a hot day for take off. It gives me a little better edge in take off distance and climb. When it’s very windy on a cross wind I have used also , slowing the landing down a couple of knots . It’s like having a $10 note extra in your wallet.
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Bruce Fenstermacher
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Re: Flap Positions on 52 170B

Post by Bruce Fenstermacher »

My first 170B had the 10 degree spot. I also used it on takeoff rather than the 20 degree position. It gave a little more positive rate of climb without the drag of the 20 degree position IMO. Would I run to the hanger with a file if I didn't have the 10 degree position? No. But I'd add it when it was convenient and it not cost was involved.
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KG
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Re: Flap Positions on 52 170B

Post by KG »

And your basis for approval for serial numbers 20267 and later is right there in the TCDS:

Wing Flaps
All Serials S/N 20267 and up eligible
Takeoff
Retracted

1st Notch
10°
2nd Notch
20°
Landing
3rd Notch
30°
4th Notch
40°
Note: S/N 20267 through 26504 were delivered without the 10° Notch.
53 170B
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nippaero
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Re: Flap Positions on 52 170B

Post by nippaero »

Thanks for the information guys!
1952 170B
N8180A s/n 25032
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gfeher
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Re: Flap Positions on 52 170B

Post by gfeher »

Bruce and ghostflyer, do you use 10 degrees on grass, or were you talking about asphalt? I fly mostly on grass now, where I always use 20 degrees for taxi and takeoff. But I've gotten so used to the 20 degree setting that when I takeoff on asphalt (without flaps), it seems sluggish. Also, the transition from 20 degrees to flaps up on climbout seems kinda long. There's always that period where the rate of climb decreases until the airspeed catches up.
Gene Feher
Argyle (1C3), NY
'52 170B N2315D s/n 20467 C-145-2
Experimental J3 Cub Copy N7GW O-200
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Bruce Fenstermacher
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Re: Flap Positions on 52 170B

Post by Bruce Fenstermacher »

Gene, for the most part my takeoffs with that plane where from asphalt. I didn't really change my technique on grass as flaps go and really never thought to compare 10 to 20 degrees on grass.
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ghostflyer
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Re: Flap Positions on 52 170B

Post by ghostflyer »

I go with what Bruce says , that’s my thoughts exactly .
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gfeher
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Re: Flap Positions on 52 170B

Post by gfeher »

OK. Thanks for the input.
Gene Feher
Argyle (1C3), NY
'52 170B N2315D s/n 20467 C-145-2
Experimental J3 Cub Copy N7GW O-200
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GAHorn
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Re: Flap Positions on 52 170B

Post by GAHorn »

KG wrote:And your basis for approval for serial numbers 20267 and later is right there in the TCDS:

Wing Flaps
All Serials S/N 20267 and up eligible
Takeoff
Retracted

1st Notch
10°
2nd Notch
20°
Landing
3rd Notch
30°
4th Notch
40°
Note: S/N 20267 through 26504 were delivered without the 10° Notch.
I don't read it quite that way at all. But approved modification ...it IS. Cessna's (Textron actually) position as mfr'r provides the approval in that their parts-approval process authorizes the early non-10-degree sector until "part supply exhausted, then substitute 10-degree sector" part number.

{Edit] TCDS does state “All” “eligible”. Thx KG
'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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