Did an aviation physics course a few years ago.
As I recall the L/D of most jet transports was around 18 or 20 to 1 at best L/D angle of attack in a clean configuration
The IAS for this constant. Have to check this as I haven't thought about it for a year or two.
IAS will correspond to min drag speed - whatever that is for the a/c. This would equate to best range speed (not LRC, although that is close)
[This message has been edited by Tinstaafl (edited 23 September 2000).]