The IDOHAP proposal was for the detailed design of two CROR models to be installed on an existing wind tunnel test rig. Each model was comprised of a pair of hubs and associated propeller blades. This work was achieved using design engineers experienced in the design of complex wind tunnel models and associated test rigs, using the Catia V5 (V16) software package. These model designs were required for CROR tests planned in the coming years using an existing CROR powered wind tunnel test rig. The IDOHAP proposal was fully compliant with the topic Call Text.