The International Cessna^® 170 Association

The spirited discussion about removing the standard parking brake going on in "The Pilot Lounge" brought to mind a question I have had for years. While I agree the standard mechanism is a hazard and should be removed I would like to have a parking brake just to hold the beast in place while I climb out to put the chocks in place! Has anyone installed (legally or not) a hydraulic locking valve such as made by Cleveland, Scott or Matco? How difficult would it be to obtain an STC for such a device? Would 337's from the days of field approvals be useful in developing an STC? I have a short list of STCs I wish the association owned and this is one of them.

Link for the Cleveland valve http://www.aircraftspruce.com/catalog/l ... valves.php

I spent some time thinking about this very thing, and came to the conclusion that TWO valves would be required because the airplane has two master cyls and two seperate brake systems.

Paul, I doubt your airplane is ever going to get back out of yoru hangar, but in case it does, if you need something to hold your airplane while dismounting you might try this:

I installed a Cleveland parking valve in our Cessna 150 Aerobat which had a system similar to our 170 installation. I did it as a field approval. It was a lease back rental airplane used for training and Aerobatic instruction flights. It was continuously being landed with the parking brakes set due to the negative g's causing the small levers on the brake master cylinders moving up the shaft and setting the brake during flight and the rudder being depressed and the brake applied at the same time by over stimulated pilots. It was amazing how hard the brake could get set. Some times it would distort the brake rod and the brake master cylinder would have to be disassembled to get it off. It P.O'd the local controllers to have their main runway blocked with a Cessna 150 when they had jets inbound.
The valve I used had the ability to operate both brake lines simultaneously. One arm being operated by the cable pull on the lower instrument panel to actuate the valve. (Operation) step on the brakes pull the handle the brakes are set. Sound Familiar

Metal Master
Glad to know it has been done ! Did you use the Cleveland valve I provided the link for? It looks like a two spool valve Two lines in, two lines out. George is right though... as long as it stays in the hangar chocks are all I need.

Several years ago after reading of the horror stories some folks had experienced with the parking brake, I disconnected mine I miss it, but don't want to get first hand experience with the problems other have had although I never had any problems and mine worked well and would hold for quiet a time when activated. I do miss it though when I happen to park on a steep incline. It can be a chore to get out, grab the chock & get it chocked before it rolls down the inclined or tries to mate with another plane nearby. I have read where some folks have retrofitted a pull type parking brake like the later model Cessna's have. That would be nice, but I imagine it would be expensive and the approval might be a challenge these days.

Now Paul, if you will get your hangar queen fixed up and airworthy, we'll shame George into furnishing the St Paulie Girl to go along with Ole Gar saying a few appropriate words at the christening party we'll have after its first withnessed flight

I just now looked at the link Paul provided, and see that it is a dual valve. That would be the ticket if anyone wanted to make the effort.

4583C wrote:Metal Master
Glad to know it has been done ! Did you use the Cleveland valve I provided the link for? It looks like a two spool valve Two lines in, two lines out. George is right though... as long as it stays in the hangar chocks are all I need.

I do not recall the part number specifcally that I used and I have not worked for that company for four years now. However the valve you gave the link for looks the same as the one I used.

I do not have the levers or the cables in my 170. I also do not have any sort of parking brake. I have never trusted the parking brakes to hold during a run up check. However I have often thought that It would nice to have a parking brake to hold the aircraft on a hill in the back country while I set my chocks and tie downs. I have a terrible vision of my 170 rolling over the bank into the trees or rocks below.

Metal Master wrote:

4583C wrote: I have a terrible vision of my 170 rolling over the bank into the trees or rocks below.

George, Post him the link you sent me with the cop chasing his patrol car!

I'll need an email address to send it to. (Courtesy Paul Wood)