Katy II is Philge's private jet in Season 3. The vessel is first introduced in Me Know What Mansplaining Is (3.03) alongside many other perks she is given as a Junior Vice President at Horizon. Katy II is named after Philge's beloved (dead) rat companion Katy who was tragically lost between Seasons 2 and 3.
She enjoys "piloting" Katy II but does not realize that her controls aren't hooked up to anything. She still wears stylish pilot attire.