The International Cessna^® 170 Association

well I don't know anything about the legality but I took mine out today as it was causing the left brake to intermittently stay on. With lots of left rudder the spring that joined the two metal tabs on the master cylinder shaft was hitting the firewall carpeting and lifting the tab. Not a good situation today in a 10 knot gusting 17 90 degree crosswind. I don't think I am going to miss it.

daedaluscan wrote:well I don't know anything about the legality but I took mine out today as it was causing the left brake to intermittently stay on. With lots of left rudder the spring that joined the two metal tabs on the master cylinder shaft was hitting the firewall carpeting and lifting the tab. Not a good situation today in a 10 knot gusting 17 90 degree crosswind. I don't think I am going to miss it.

Correct, You just described the exact reason to remove the parking brake.

Is it impossible to adjust the rudder pedals to where they cannot reach the firewall carpeting?
I found that I often needed my parkng brake when flying alone in the Idaho back country and having to stop and park on an incline that was steep enough for the airplane to start rolling before I could get out to chock the wheels. The Sulphur Creek Ranch parking area on the south side of the runway was one such area. The Big Creek parking area also had some slopeing areas.

The caveat to the whole parking brake issue (in my experience) is "when not properly adjusted" it is a safety issue.

The rudder pedals have no stops on them to prevent firewall contact. The rudder horn does and cable length dictates if the pedal can reach the firewall. If your rudder cables are adjusted too long, your pedal may hit the firewall and trip the brake tab.

In my case, once I adjusted the cable length and the brake pull cable the system operates fine.

But, it's a finicky beast and has no indication that it's about to or just has done you wrong until your wheels touch the ground. I find myself tinkering with it frequently to make sure it's all OK and someday I will replace it with a valve system.

I know there are folks on this thread that think the parking brake is flat out dangerous and I'm playing Russian Roulette with every landing but that's my experience with the system. Take the time to keep it adjusted and working properly or just take the thing off all together. The danger is anywhere in between.

David I think you are right in that the parking break system isn't as dangerous if one fully understands the entire system including the pedals and there adjustment. And then one stays after the system to make sure than nothing has changed and interferes with its action. As you note even then you have no idea until your wheels hit and it is to late. This is why I'd rather see them removed removing the issue and deal with a rolling aircraft on those occasions I have to park on a hill.

17 degrees is of course the rudder travel but it has nothing to do with setting the peddles correctly. This measurement is taken from the firewall to the back of a spot on the peddle and should be 6". The measure is set by the turnbuckles at the rudder. See this thread for more discussion. http://www.cessna170.org/forums/viewtop ... ent#p68368

I should have added the early 170's have the serrated style master cylinder shaft...this is why my park brake is no longer serviceable, I replaced both of my master brake cylinders, so the "old" park brake system is not workable. As for the later models, rigging is the issue. cheers