C172 Oleo Strut

[berge7f9]

What rules of thumb do people have approximately how much of the polished oleo strut of a Cessna 172 should be showing during a preflight?

[dpilot83]

I always heard and said three finger widths...there have probably been more than a few instances of going with much less than that and just being careful though.

[Ian J]

I got my butt chewed about this very question one time. The DE who asked didn't like my "rule of thumb" answer, and told me the only way to know what the strut should be at is to check the Cessna Maintenance book. Sigh... I forget what the actual measurement range turned out to be, but wouldn't you guess, 2-3 fingers turned out just fine.

[PacMan4x4]

BERGE...

Your question is a good one....the proper dimension for nose strut is 5.15" (min) to 5.30" (max) with 45 psi. Keep in mind that this isn't the dimension ya'll are more than likely using when pulling on the prop to check the "sponginess" . The dimension above is when the aircraft is sitting there and not yankin' on the prop. I also use the 3 finger method to check the compressed strut, but it's not the rule--I won't stop a flight because of it. Now, a word of advice for all of my fellow aviators....if you go out to preflight with ruler in hand, and then commence to tell your friendly mechanic that the nose strut is at 5.00" and below minimal strut extension dimension--DUCK!, because the maintenace manual is in flight towards your head :-)
Hope this helps.