Hello,
Currently on ebay is a photo of an object which may be a decoy or a target or, who knows, abstract art at:
https://www.ebay.de/itm/Altes-Foto-F...AAAOSwvypgN9lu
Not sure what is shown, presumably something constructed by hobby constrctors of some kind. Certainly it doesn't seem to have space for an actual engine.
Regards,
Clint