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Pumpie
01-12-2012, 02:01 PM
Hey,

Could soomebody give scheme of parking brake lever's mechanism or photo of the gear?


Thanks in advance

weyes
01-13-2012, 06:10 AM
I am asking myself the same...

I found a pdf on landing gears (http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&sqi=2&ved=0CCQQFjAB&url=http%3A%2F%2Fwww.smartcockpit.com%2Fdata%2Fpdfs%2Fplane%2Fboeing%2Fb767%2Fsystems%2FBoeing_767-300-Landing_Gear.pdf&ei=5Q8QT4zdN8uQswamwphK&usg=AFQjCNEPLzXbnTm_jB7wfIICtgyyT7bjTA) on the net. It explains also how to set/unset the parking brakes. From there it seems that the handles has to be set only (unsetting happens automatically acting on the pedals).

tomenglish2000
01-13-2012, 10:05 AM
Hello all!

The PDF says it all really. In the case of Boeing aircraft it is as follows.

The parking brake is applied by locking the rudder pedals in the braking position. So to apply the park brake you use your rudder pedals to apply full brake and then pull the parking brake lever. The brake lever pulls a cam into place behind a lever on the rudder pedals when they are fully down. Releasing the rudder pedals makes them spring up slightly against the cam which holds the cam in its position and the cam prevents the rudder pedals from returning to the no braking position. Pressing on the rudder pedals to move them off the cam allows the spring loaded cam to return to its stowed position, pulling the parking break lever down as it does. The rudder pedals can now return to the no braking position.

Pulling the park brake lever when the rudder pedals are not all the way down will make the cam hit the lever on the pedals so you cant pull it up until the rudder pedals are down far enough.

So to apply park brake: Push fully down on the rudder pedals, pull the park brake lever and hold it, release the rudder pedals, the rudder pedals will move slightly up and engage the cam, you can now release the park brake lever which will not return down as the cam is locked by the lever on the mechanism.

To release the park brake: Push fully down on the rudder pedals (will only be a small amount further from the parking brake position) and the cam will be freed from the lever, the cam is spring loaded to return the the stowed position and this movement will pull the park brake lever back down.

Its pretty difficult to describe without a picture so here is a crudely drawn paint version of what I have seen in the AMM.

http://i133.photobucket.com/albums/q66/tomenglish2000/parkbrake.jpg

Tom.

tomenglish2000
01-13-2012, 10:09 AM
Just to add to that above, the locking mechanism applies to both pedals on the captains side at the same time so both pedals need to be down far enough to engage the park brake. As the brake action of the first officers pedals are linked to the captains side, the locking mechanism is only needed on the captains set and both sets will show the status of the brakes.

Tom.

737NUT
01-13-2012, 11:55 AM
I this is for a 737?? If so, very easy. Get a Door Lock actuator off of ebay, paid 1.79 for mine. when you push on the brakes either via a relay or output from an interface have the actuator activate

Pumpie
01-13-2012, 01:41 PM
Thank you, could you take me a photo of your mechanism

Philb737
01-13-2012, 02:05 PM
you can also use a power trunk release solenoid kit, usually around $15 on ebay:
http://www.ebay.com/itm/Power-Trunk-Release-Solenoid-Kit-/190625509904?pt=LH_DefaultDomain_0&hash=item2c622a7210#ht_909wt_1037