Most light airplanes have a glide ration which approximates about a 6:1 ratio or so, though some as little as 3:1
Not true SN3.
A Cessna 152 is around 9:1, a Warrior around 11:1. The worst you are likely to get in a "proper aeroplane" (not a microlight) is better than 7:1, and in a retractable you might get twice that if you manage to stop the prop (or have managed a double failure in a twin, and feather the props).
Lift:drag ration is equal to glide ratio. If your best lift:drag ratio was 3:1 you'd never get airborne in, for example, a 1100 kg aircraft with 160 hp.
If you put the following in Google (it sorts out all the units) "160 hp / 75 kt" it tells you that the maximum thrust from perfect transmission of 160 hp at 75 kts is 3,313 N. Maximum lift would be three times this, 9,919 N. The force just to hold up a 1100 kg aircraft is 10,791 N.