An active Aeroshuttle
A docked aeroshuttle
An aeroshuttle detaching
The Aeroshuttle in Crewman Daniels' Database
The Aeroshuttle (or AeroWing) is a large shuttle attached to Intrepid-class starships.
The Aeroshuttle is docked to the underside of the vessel's primary hull. When detached, it was capable of atmospheric flight as well as interstellar travel at speeds up to warp 3. The Aeroshuttle cockpit is designed for a crew of four.
A graphic of the Aeroshuttle also appeared in Daniels' 3-dimensional database, while it was being viewed by Captain Archer and T'Pol in 2153. (ENT: "Future Tense")
Background
The AeroWing name, as well as many of the above references were derived from the VOY writer's guidebook.
Rick Sternbach's Star Trek: The Magazine article, "Intrepid-Class Lineage" noted that "The Aeroshuttle was the only upgraded component to the Intrepid-class that remained in the development cycle long after the other major systems had been frozen and released for fabrication and assembly. Based on the existing Starfleet runabout planform, the Aeroshuttle was given a 450 percent increase in atmospheric flight and hover endurance over standard shuttlecraft. This was accomplished through the use of hybrid microfusion and EM driven airflow coil engines. Although the Aeroshuttle spaceframe and basic systems were completed by Stardate 46875.3, final outfitting of mission-specific hardware was delayed until simulations and flight testing with the USS Intrepid could be completed."
Viewers never got to see the Aeroshuttle in action due to the limitations of television and storylines as it were. Therefore for the sake of those that wondered, the Aeroshuttle was considered an unfinished piece of Voyager eventually stripped for parts as situations arose due to the unique predicament that the crew was in.
A conjectural design for the Aeroshuttle can be found at ACTD, in section 9.3