Abrasion strips

How to keep the Cessna 170 flying and airworthy.

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KS170A
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Re: Abrasion strips

Post by KS170A »

FredMa wrote:Thanks for clearing that up. Does anyone know the cost of the cessna boot? I'm sure it isn't cheap. I am only looking for erosion protection so I will probably go with the tape.
Yingling's online site (http://www.cessnadirect.com) indicates a list price of $133.00, with their price as $105.70.
--Josh
1950 170A
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MoonlightVFR
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Re: Abrasion strips

Post by MoonlightVFR »

The strips are important for a number of reasons.

Very important to do good job of installation.

About 24years ago I watched as my toddler son ran around the airplane and did not discern the horizontal stab since its height was same as his forehead. I saw it happen with aloud CONK ! Momentarily stunned.

I was taught that the strips were necessary for landing in short brush fields and sandbars. Check at every preflight for secure attachment.

Regards
gradyb, '54 B N2890C
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GAHorn
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Re: Abrasion strips

Post by GAHorn »

MoonlightVFR wrote:The strips are important for a number of reasons.

Very important to do good job of installation.

About 24years ago I watched as my toddler son ran around the airplane and did not discern the horizontal stab since its height was same as his forehead. I saw it happen with aloud CONK ! Momentarily stunned.

I was taught that the strips were necessary for landing in short brush fields and sandbars. Check at every preflight for secure attachment.

Regards
LOL...(I presume your son hit a rubber strip...?? and is OK.)

TAKE NOTE GUYS! The leading edge of horiz stabs can be critical for controllability reasons.
I recall the description of Cessna test pilot Wm. Thompson describing how merely moving production of a single engine model from one facility to another resulted in the inability to recover from intentional spins! 8O
The aircraft being spun had been assembled at the new facility with original tooling, but an almost imperceptible change in horiz stab leading edge resulted from moving the jigs from one facility to the new one. The change was only noticed after a customer complained about handing qualities (which unimaginably passed by the production test pilot team.)
Thompson almost had to bail-out when the airplane went into an unrecoverable spin from 10,000' down to low altitude. No amount of power or flight-control manipulations would effect a recovery and he was unable to explain how/why it came out of the spin.

Anyway.... that's actually one reason I do not personally desire any abrasion strips on any airplane I fly. I do not believe sufficient tests have ever been properly conducted on them and Thompson's story haunts me.
'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. ;)
bigrenna
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lowNslow
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Re: Abrasion strips

Post by lowNslow »

gahorn wrote: No amount of power or flight-control manipulations would effect a recovery and he was unable to explain how/why it came out of the spin.

Anyway.... that's actually one reason I do not personally desire any abrasion strips on any airplane I fly. I do not believe sufficient tests have ever been properly conducted on them and Thompson's story haunts me.
Sooo... what makes you think it was the abrasion strip? :wink:
Karl
'53 170B N3158B SN:25400
ASW-20BL
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GAHorn
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Re: Abrasion strips

Post by GAHorn »

I never said or insinuated abrasion strips had anything to do with it, and neither did Mr Thompson,
... The implication is, that if a minor, inadvertent change in shape of the horiz stab leading edge
can pass unnoticed by factory test pilots, and result in changed flight characteristics which can kill
us......... Then I personally will not be installing abrasion strips on m my airplane, (and I am frankly surprised Cessna so cavalierly sells them for wide general purpose use.)
'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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MoonlightVFR
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Re: Abrasion strips

Post by MoonlightVFR »

Many years ago there was a. C180/185. That suddenly picked up a bad habit of misbehaving just prior to touch down

Owner put the -A/P in right seat to prove the point.

It repeatly would stall nasty 1.5 FT in the air very slow speed. It would just dump land.

Something was going on and it was not easily solved.

But FINALLY a solution.

The abrasion strip was detached both both sides horizontal stabilizer. when aircraft slowed ,really slowed down prior to touchdown the abrasion strip was moving forward and up disturbing airflow over airfoil. Not enough air pressure to hold the strip tight against front of airfoil. after landing every thing looked normal, abrasion strip was tight against stab leading edge.


I think Kas Thomas of LPM wrote a definitive article in early 80's.


I favor the abrasion strip even though I try to stay out of the bushes in every aspect of life.

regards
gradyb, '54 B N2890C
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