According to MIT Technology Review's The Download newsletter, the US military is engaged in a race to develop fake blood. The effort aims to create a substitute that could be used in place of real blood for transfusions on the battlefield.
The newsletter points to a February 2007 incident in which a US military helicopter carrying blood to a field hospital was shot down. That event illustrates the risks involved in shipping donated blood to frontline medical units, and it helps explain why the military is seeking a more reliable alternative.
As the source notes, the development of synthetic blood could transform how combat casualties are treated, though the newsletter does not provide further details on the current status of the research. The single source offers only this glimpse into the program, so the broader timeline and technical challenges remain unclear.