The International Cessna 170 Association

My 170A has the brake calipers located to the rear of the gear leg, but I recently
saw a picture of a 170B that has them on the front of the gear leg. Surely that
wasn't changed between models. Which is correct?

Buckeyejim wrote:My 170A has the brake calipers located to the rear of the gear leg, but I recently
saw a picture of a 170B that has them on the front of the gear leg. Surely that
wasn't changed between models. Which is correct?

Rear of the gear leg was the standard location on all 170's. They would work the other way also, but very hard to fit the wheel pant attach bracket if you wanted them. You must realize that there have been so many changes and modifications to these 60+ year old planes, they would fill a large book..... Some of them approved, some of them, who knows..???

I wonder why someone would mount the calipers on the front? If these old planes could only talk!

Buckeyejim wrote:I wonder why someone would mount the calipers on the front? If these old planes could only talk!

Your brakes and likely all you've seen are modifications from the original Goodyear brakes they came with. So depending on how they were modified, determines front or back. As far as brake operation, there is not difference. Goodyear calipers where behind, and that is where the brake line runs so if you took a poll you probably going to find more aft than forward.

Buckeyejim wrote:I wonder why someone would mount the calipers on the front? If these old planes could only talk!

Mine are on the front because I switched from crosswind landing gear and kept the hoses. The routing just worked better with the calipers on the front. Also, they’re in a convenient location to reach down and give them a rattle on preflight.

If you install the dual piston Cleveland wheel cylinders with the FA Dodge STC the kit installation instructions call for installing them forward of the axle.

Tim

Golly I wonder why they put them on the front in the later years?

There is a belief by some that by placing the calipers forward they present the back of the caliper to deflect grass and debris instead of allowing those to possibly enter between the brake linings and the disc.
I operate off grass (with aft-mounted calipers) and it appears to me that the gear-leg and axle do similarly. (But, I also operate with original fairings which protect the brakes pretty well.) I doubt it makes any difference from a performance standpoint.
The forward position (in the 3-point stance) provides slightly more ground-clearance and may offer a bit of protection for the linings in the form of "slinging" off of water, etc. from the disc.

gahorn wrote:There is a belief by some that by placing the calipers forward they present the back of the caliper to deflect grass and debris instead of allowing those to possibly enter between the brake linings and the disc.
I operate off grass (with aft-mounted calipers) and it appears to me that the gear-leg and axle do similarly. (But, I also operate with original fairings which protect the brakes pretty well.) I doubt it makes any difference from a performance standpoint.
The forward position (in the 3-point stance) provides slightly more ground-clearance and may offer a bit of protection for the linings in the form of "slinging" off of water, etc. from the disc.

Like this???

That's a great illustration, Paul! ... but I believe if you look closely (in person as the pic doesn't allow as much detail) you'll see that the axle mowed the grass and the wheel rotation brought the grass "around" to jam between the brake caliper and the surrounding disc/axle assy. more than actually jam any into the disc-lining area. A C-180 landed out here at my place and I noticed the grass was bunched up on his forward-mounted brake-caliper also, but the owner commented that it usually blows back off in-flight. I don't know how well that might clear-out on the rear mounted calipers as personally I operate with fairings and they keep the calipers clear. You or someone else will have to tell us about that.

Paul, did Del forget to tell you that 83C isn't to be used to rake hay on the ranch?

No Paul, you can't claim your plane as agricultural equipment for a tax write off.

Mine came with pants and front mounted calipers when I acquired it.

Now you tell me I can't write off agricultural use? Shoot........

I don't know..looks like a very efficient mower to me!

Just a thought while we're on the subject with pics already posted... The brake lines can be subject to damage on unimproved surfaces unless the brake lines are routed behind the landing gear spring/strut for protection. On rear mounted calipers this is easy as long as the hose-lengths are carefully measured when mfr'd. On forward mounted calipers the best way IMO is to route them over the landing gear spring/strut rather than under if at all possible.
Hiding them behind the spring also reduces aerodynamic drag.