The Brunswick-Balke-Collender OQ-4 was a prototype drone built in the United States by the Brunswick-Balke-Collender corporation.
The OQ-4 was one of a very few aviation-related ventures undertaken by Brunswick-Balke-Collender, which was basically a non-aviation company. It was similar in some respects to the Radioplane OQ-2, including a 12-foot wingspan. Although a few prototypes were built, the OQ-4 was not put into production, perhaps because Radioplane and Frankfort could produce enough target drone so that another production line was not necessary.[1]