I have seen on other oleo-strut airplanes that they have put on the strut. When the ground loads on landing gear occur strut displacement changes and by a proximity sensor they get wow signal. I couldn't understand ; how do they get wow signal from a leaf spring type main landing gear. Thanks,
On fixed main landing gear how does an airplane get WOW signal. Where did they put the WOW sensor?
The Cessna 172RG for example has a WOW sensor located on the nose gear, since it is the oleo type which lends itself to WOW switches much more easily. This isn't as good of a solution as putting the switch on one or both of the main gears, however, as the nose gear can fully extend during taxi or takeoff roll before rotation, and if the gear handle happened to be up, so goes the gear. But, it is better than nothing at all.
On fixed main landing gear how does an airplane get WOW signal. Where did they put the WOW sensor?
The wow sensor is something only large airplanes have. Not that small planes couldn't have the sensor, but generally speaking their systems are not that complicated.
The wow sensor is just one of several sensors the computer will look at to determine what mode the airplane should be in. For example, on a Challenger (and crj) there are three modes, ground, taxi, and air.
If, for example the wow sensor shows weight on 3 wheels, the engines are off and the cabin door is open, the computer can determine that the airplane is parked and will operate in ground mode.
Its fair to say that you aren't going to find any fixed gear airplanes with that kind of sophisticated computer systems. I would say the cessna (columbia) 400 is one of, if not the most advanced fixed gear airplane out there and its leaps and bounds away from being sophisticated enough to need any kind of computer system that can determine if its on the ground or not.
I'm laughing at Grumpy Geezer's answer! He is correct, as is Warbird.
Although there are several systems that may need to know whether there is weight on wheels depending on the aircraft's complexity, the PRIMARY reason for a WOW switch, is to keep the landing gear from retracting on the ground.
And just so you know, every airplane with retractable gear has a WOW switch of some sort, regardless of it's size or complexity.
RTFQ..........I love that!
Looks like Warbird actially read the question. If you have a fixed gear airplane there is no need for the WOW switch, thus they are not installed.
Anything with spring leaf gear doesn't need a WOW switch.
