Un "wing" es un grupo de varios escuadrones.

La traducción literal "para entendernos" (lo digo porque es fea, pero a lo mejor te sirve para ver las categorías) sería: Gene del 5º escuadrón de la brigada de cazas.

Si no quieres dejarlo en inglés, otras opciones serían términos militares de ránking un poco más elevado, como batallón, brigada, etc. Si el juego se desarrolla en un país imaginario te puedes permitir más libertad. Si es de Estados Unidos (o pasa en Inglaterra, algo menos probable) sí que se trata de términos con un significado concreto.

Te copio las definiciones:

Inglaterra y Commonwealth:

The term originated with the British Royal Air Force (RAF). In the RAF and other Commonwealth air forces, a wing is usually made up of three or four squadrons. In these air forces a Wing is subordinate to a group. Although originally commanded by a Wing Commander (equivalent to a Lieutenant Colonel in other air forces), wings are also commonly commanded by Group Captains. The name wing may also be used for non-flying units, such as the infantry forces of the RAF Regiment, (in which a wing equates to a battalion). In the Canadian Forces Air Command, the size of a wing (base) varies greatly and may be comprised of personnel numbering hundreds or thousands.

Para Estados unidos:

By comparison, in the United States Air Force, a wing is a larger unit that is normally subordinate to a Numbered Air Force. Most USAF wings are commanded by a Colonel, but some are commanded by Brigadier Generals. USAF wings structured to fulfill a mission from a specific base, and contain a headquarters and four groups: an operations group, a maintenance group, a medical group and a mission support group. Such a wing is referred to as a Combat Wing Organization, which is comparable to a brigade in the US Army. Other wings, such as Air Expeditionary Wings, exist for various other purposes, and their scope may extend to one base, one theater or worldwide.

Carrier air wing (or Carrier Air Group) consists of seven squadrons, four of which are of fighters or fighter-bombers.

In the United States Marine Corps, a wing is an overall command consisting of at least two Marine Aircraft Group and their subordinate squadrons and support units.