The Whirdlebirb, also known as the Whirdlebird in Shirerithian demotic, is a uniquely Benacian interpretation of the concept of a helicopter. It's origins can be derived from Ashkenatzim notes about a Babkhan design, the originals to which were long since lost to the atomic holocaust which ravaged Eura. The Whirdlebirb owed its rebirth to the successful Minarborian prodding of a certain revivicated martinet into interpreting notations recovered along with his person from the bowels of the Yabotinsky Fortress in Nackholm.
In the aftermath of Minarboria's fall the type began to proliferate throughout Benacia, the Shirerithian type cleaving to the original design whilst the Kalgachi re-imagined the type in line with their own experiences and geologically elevated circumstances.
Over time the Whirdlebirb has become a principal tool in the containment of Tyrannocricetus aliger, being one of the few craft capable of both outrunning and outmanoeuvring the creatures in close combat - although the latter's limited flight capability has claimed a number of Whirdlebirbs in air-to-air engagements. Such losses are considered acceptable by the Whirdlebirb's respective operators when measured against the much higher casualty rate of ground forces attempting to take on the gigantised cricetids.