A B-17 is a ________ and the 17th __________________.

The B-17 is indeed classified as a bomber, which is a type of military aircraft specifically designed for the purpose of delivering explosive ordnance against ground and sea targets. The B-17, in particular, was known for its bomb-carrying capacity and played a pivotal role in World War II as part of the strategic bombing campaign.

The "17" in B-17 refers to its model number, indicating that it was the 17th design produced by Boeing in this series of aircraft. This nomenclature is a common practice in military aviation, where the letter often signifies the aircraft's type and the subsequent number indicates its version or model. Understanding this naming convention provides context to both its purpose and design lineage.

This combination effectively highlights the dual significance of the B-17 as both a type of bomber aircraft and its designation within a series of designs.