N85...
I'm referring to the speed that will give the best distance to reach that safe landing spot.
After many tests and with 20 gallons and only me in my avid MK4 I have found that, with no head or tail wind 50-55 MPH indicated works to give me the best distance.
I am seeing a solid 10:1 ratio.
Of course, wind will have an effect. If in a 50 mph head wind I would make little forward progress. That gives a couple options: Decrease AoA to increase speed if you absolutely have to continue on the same course or do a 180 and pick up a tail wind and increase your AoA (reduce speed) and maximize your available distance.
My tests were done from 5000 AGL with engine idling. Next I will fly to a local dry lake and actually shut the engine off for glide tests down to the surface.
I have the glide ratio app on my phone at present and will use it more when IFLY has it in their app. Sem like a no brainer and another sales incentive.
Just another tool that might help save your bacon when it goes silent.
John M