I have seen this happen in a friends 360. There was a modified wiring:

 

1. From the gear selector up side there was a throttle position switch to start a buzzer (gear warning)

2. A float switch also energized the same buzzer for low fuel warning

 

Now if you are a little low on gas when you enter final the fuel will slosh forward from the deceleration and close the float switch. The power will go back thru the low throttle switch and energize the gear up relay even though the gear selector is in down position. The gear down relay is off since the pressure switch is open on the down side

 

In my friends case it only partly retracted one gear, which collapsed on rollout. Goes to show any wiring modificaion must be carefully analyzed, and dont be too smart :)

 

Sven Jerlhagen

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