[aerohead]

Not to slam their research,but here's some considerations.
*at 1/15-scale,the test section flow velocity would need to be a minimum of 300-mph in order to achieve critical Reynolds number.
*The model's frontal area should not exceed 5% of the test section cross-sectional area.Clearly not the case.
*at 300-mph,transonic flow would be present with shockwaves forming on parts of the body,blocking airflow in those areas.
*at 300-mph,the boundary layer would be thick enough on the walls,ceiling ,and floor of the test section as to choke off the flow,creating a velocity acceleration discontinuity over the length of the model,compounding the blockage effects and supersonic jets.
*at 300-mph,the wheels and lower body of the model could be immersed in the boundary layer,which would never happen at 1:1 - scale.
--------------------------------------------------------------------------
If the authors had actually read Hucho's book,they'd know these things before they ever began,and never proceeded.
Another thing,these sorts of body details cannot be examined at this sort of scale level.Maybe 1:2 scale,then 1:1 scale verification later.
I think it's one of those Donald Rumsfeld moments in science,where the investigators didn't know the known knowns.