@b3lt3r That's actaully close to the real Aircraft. All things being equal, the Airbrake is fully opened at 100' AGL. This is done by pulling the handle back, it will physically stop short of the SPLR setting. Once you've touch down, you then pull the handle back to the SPLR position.
In a serviceable aircraft, it is not possible to deploy the Spoilers in the air. You could hang off the handle and it shouln't occur.
On later 146s and all RJs, there is an auto spoiler function. The spoilers will automatically deploy on landing once certain weight on wheels logic is satisfied.