An airport sando is less a single recipe than a context: the premium boxed sandwich bought before a flight, often as omiyage, the souvenir food brought home to family and colleagues. The base form is the familiar Japanese sando on soft crustless shokupan, fruit and cream, egg salad, cutlet, or ham, but the airport and station setting raises the stakes. These are made to travel well, to look composed through a clear box, and to carry the name of a region or a known shop, so the bread, the filling, and the presentation are all pitched a notch above the everyday convenience-store version. The bread and the filling still depend on each other in the usual way, but here durability and gift-worthiness are part of the brief.
The craft shows up in materials and assembly. The shokupan is typically a richer, finer loaf that stays soft after hours in a bag, and the filling is more generous and more precisely placed than a grab-and-go sandwich, so the cut face stays photogenic for a fruit or egg cross section. Because it may sit unrefrigerated for a stretch of travel, a well-made one is built with fillings that hold and a box that protects the shape. A good airport sando arrives looking as it did on the shelf, the bread still tender, the filling intact and clearly displayed. A weak one trades on the setting alone, charging a premium for a sandwich that has slumped, dried at the edges, or smeared its filling across the wrapper by the time it is opened.
The category overlaps heavily with the standard sando family, the fruit sando, the tamago sando, the katsu sando, each of which has its own conventions and failure modes far beyond this travel framing. Each of those deserves its own article rather than being crowded in here.