our house brick clearly must have an L/D ratio of zero.. entirely reasonable. Likewise, our perfect glider must have an infinite L/D ratio
I like that explanation.
I was always talking glide endurance since glide range is a trade-off between forward speed and endurance just like powered flying for range.
Gliding endurance is all about the ratio between weight and the vector addition of CL and CD
That comment makes the driagrams provided earlier a little clearer. However, isn't endurance at a maximum when total drag is at a minimum? If this is the case then where does CL come into the equation? Or are you using CL to determine the angle of attack for min drag speed which of course varies with weight?
Regards,
DFC