C-180 Gear

[simon]

Does anybody know what the deal is with putting 180/185 gear in a 170B? I know that there is at least one STC to do it, but are there more? What part and/or serial numbers are called out in the STC('s). I know that the early 180 gear was 11/16" and the later ones are 3/4". I would also imagine that the forward sweep was changed througout the years and I was just wondering which gear was applicable to our airplanes. I am also aware of the concerns associated with putting a stiffer gear leg in as it relates to the stresses on the gearbox structure, but I am just curious about the details.

Thanks

[MeeksDigital]

i don't know a whole lot about the installation, parts etc, but i do know that a very common/recommended modification is to put the P. Ponk bracket kit in the gear box when installing the 180 gear.

My 170A has the 180/P. Ponk conversion and it's verryy nice! Much stiffer then standard 170 gear, and I haven't worried about it once, having done many x-wind and off-field landings.

[Indopilot]

After a quick cruise thru the parts manuals for both the 170 and a 1970 180 most of the gear box parts are the same. At least they have the same part numbers.

[N419A]

The XP Mods site has a good description of the differences in gear legs. The only thing you gain with early 180 legs over the late 170 legs (lady legs) is 1.5 inches of length (they're the same steel and thickness). The next model you would gain length and wheels forward. And, the last 180/185 legs you would get stiffer and wheels forward. I have a set of -7,-8 legs .75 thick and wheels forward haven't put them on because I don't want wheels forward. I'd rather keep the tail light.

Paul

[GAHorn]

....I was just wondering which gear was applicable to our airplanes. ...Thanks

Simon...(at the risk of being sarcasticly didactic)... the gear which is applicable to your '53 B-model is the one which came on it.

This is especially true if your 53 B-model is subsequent to serial 25612, which has the later "lady legs" (so-called because of the small "ankle" just above the axle. This later gear is stiffer, with a slower spring-rate and has a slightly "bow-legged" look when viewed from the front. It is also "handed", meaning it is no longer interchangeable left-right, as the early gear was.)

The earlier models of 170's were equipped with a Wittman-style spring gear that had a higher spring-rate, and some pilots feel it is not sufficiently stiff for easy handling. (I don't feel that way...but I'm fortunate that I have serial 25713 and don't live with the early gear on every flight. I never found the early gear a problem at all, but I can see the advantage/improvement of the later "lady legs". I would NOT spend any of my money changing early gear to a later gear system. I would spend any available money on more meaningful maintenance and improvements, if it were my choice to make.)

The 180/185 gear legs that some folks like, do indeed alter the aircraft in a couple of significant ways.
First: It raises the forward portion of the cabin/fuselage and provides greater prop-to-ground clearance. This might be helpful to avoid prop damage if operating on extremely rough, unimproved surfaces, but probably only if 3-point take-offs and landings were used on on those surfaces exclusively.
Second: It alters the distribution of weight upon the wheels, although only slightly if the earlier "wheels aft" gear is used.

I personally think it makes the airplane look ungainly. But looks are only a secondary consideration for a working girl.

[simon]

Thanks for all the replies guys. Is there a basis for approval to put the -7 and -8 (wheels forward) gear on?

[GAHorn]

Thanks for all the replies guys. Is there a basis for approval to put the -7 and -8 (wheels forward) gear on?

From the MX Library:
(Eric Leclercq, TIC170A member #7382 Quebec is the holder of the STC in Canada & USA to install C180 gear legs,p/n 0741001 through -8 or p/n 054118-2 thru -3 (lady legs) on all 170,170A,& 170B models. Contact him at 450-452-2567, new email: eric170@videotron.ca
(old email reported no longer effective: ericc170@sympatico.ca )

[simon]

Thank you George

[bsdunek]

Good thoughts George. The longer legs seem to make the 170 look like a 'bigger' airplane when I park mine next to them.
I've decided that I like the originals and will keep them. I would think it's easier to get the tailwheel on the ground first with slightly shorter legs, which may help on crosswind landings.
Maybe I have a 'low rider' look?

[Jr.CubBuilder]

The origonal gear legs are lighter to, food for thought.