The present disclosure provides systems, apparatuses, and methods relating to a fan apparatus including a lift fan mounted in a duct and a cover for the lift fan. In some examples, a fan apparatus has a louvered cover including louvers having different chord lengths and/or different projection distances relative to one another when the louvers are in an intermediate (transitional) position. In some examples, a fan apparatus includes a louver actuation assembly configured to move louvers of the fan apparatus rotationally and translationally between open and closed positions. In some examples, a fan apparatus includes a fluid-actuated sealing assembly configured to form a seal between a sealing member and a cover, such as a louvered cover.