The Aero Shuttle and its docking bay for the U.S.S. Voyager.
The Aero Shuttle was part of the design for the Intrepid-class starships. The shuttle was designed for atmospheric excursions, and was warp-capable. It could also be considered the captain's yacht, which larger-sized starships had.
The Aero Shuttle resembled a Danube-class runabout with short wings. Had the vehicle been used during the filming of Star Trek: Voyager, the production team planned to re-use the runabout sets from Star Trek: Deep Space Nine.
The Aero Shuttle, however, was never utilized in the TV series. The probable reason was the cost of a new model and filming the launch sequence (the bane of every Star Trek series that used physical models). This is why the Enterprise's captain's yacht, the Cousteau, was never used until the film Star Trek: Nemesis. And when Voyager's crew built the Delta Flyer, which proved to be very popular the need for the Aero Shuttle vanished.
There are some sites that state that the reason the Aero Shuttle was never used is because the producers thought it would upstage, or appear redundant, after the Cousteau was introduced in Nemesis. I don't see how that could be, as the Voyager television series ended before Nemesis was even released.
The Aero Shuttle has seen use in comic books, where the special effects budget is only limited by what the artists can draw on the page.