We didn´t just match a few existing systems together, no we developed a complete new rescue system. Not only the shape is new, but also its mode of FUNCTIONING. Immediately after deploying and opening of the canopy, the X-TRIANGLE sinks vertically and does NOT generate any FORWARD MOTION. The canopy is FULLY
SYMMETRIC straight after the opening. There is no pre-brake like on a rogallo canopy.The pre-brake on a rogallo brings just a little slow down of the forward speed and definitely NO slow down to zero speed. A rogallo rescue is already from the construction side build asymmetrically and has always a GIVEN FORWARD motion, without this motion the rogallo would stall like a paraglider.
Rescue parachutes often have a symmetrical shape: they are not wings. The sink rate is therefore on a vertical basis, as indicated above. Consequently, the calculation of drag as I have done is possible.
It is a reason why for this “planar rescue” drag coefficients are higher. That said drag calculation would be more precise by using the projected area beside the surface but I don’t have both data for the specifications of the rescue parachutes I examined, although a video indicates a flat area of also 19 m² (at 0:07) for the Yeti UL, S(19).