Maintenance mode for aircraft vacuum toilet

A method of controlling an operation of a toilet system on-board an aircraft, the toilet system including a toilet bowl, a fluid valve controlling input of fluid into the toilet bowl, a flush switch configured to be activated by a user, and a controller configured to operate the fluid valve, the method comprising:

• detecting an activation of the flush switch;
• monitoring a flush switch activation time period;
• determining whether the flush switch activation time period exceeds a preset threshold time period;
• in response to determining that flush switch activation time period does not exceed the preset threshold time period, initiating a standard flush cycle and controlling the fluid valve to allow fluid input into the toilet bowl for a first period of time to a first preset level in the toilet bowl;
• and
• in response to determining that the flush switch activation time period exceeds the preset threshold time period, initiating a maintenance mode, wherein
• in the maintenance mode, the controller is configured to control the fluid valve to allow fluid input into the toilet bowl for a second period of time to a second preset level in the toilet bowl, the second period of time being longer than the first period of time, the second preset level higher than the first preset level.