172_driver
23rd Jan 2015, 11:19
Best PPRuNers,
The picture below is from my current type, 737. I am trying to fully understand the downlock mechanism. Am I right in thinking the springs "pull" the downlock over-center? (I actually can't tell for sure if the downlocks are over-center geometrically, are they?) In between the springs I gather there's an hyd actuator? With the gear extended is there full system pressure holding the downlock over-center as well? Hence, spring+hyd pressure keeps the downlock from folding?
The opposite then, am I right in thinking when the gear is retracted the hyd actuator extends, working against the springs (extending them) and the downlock folds to the left in the picture?
http://i307.photobucket.com/albums/nn287/patrikcertain/Downlock.jpg (http://s307.photobucket.com/user/patrikcertain/media/Downlock.jpg.html)
The picture below is from my current type, 737. I am trying to fully understand the downlock mechanism. Am I right in thinking the springs "pull" the downlock over-center? (I actually can't tell for sure if the downlocks are over-center geometrically, are they?) In between the springs I gather there's an hyd actuator? With the gear extended is there full system pressure holding the downlock over-center as well? Hence, spring+hyd pressure keeps the downlock from folding?
The opposite then, am I right in thinking when the gear is retracted the hyd actuator extends, working against the springs (extending them) and the downlock folds to the left in the picture?
http://i307.photobucket.com/albums/nn287/patrikcertain/Downlock.jpg (http://s307.photobucket.com/user/patrikcertain/media/Downlock.jpg.html)