The NAV-AID RULE and the NAV-AID PLUS solve the most troublesome aspects of visual navigation, off-course heading corrections and unexpected diversions.
N AV-AID RULE and NAV-AID PLUS DESIGN PATENTS:- Australia 51271, Canada 245/30913, U.K. 936201, N.Z. 11461, U.S.A. 21627
The NAV-AID PLUS offers the extra benefit, at little extra cost, of two instruments in one. An in-built circular computer allows you to do your pre-flight and en-route calculations of ground speed, distance and time intervals without the need of another instrument.
The central circular slide rule enables the pilot to solve problems involving time, speed and distance. The triangular index, A positioned at the "60 minute" graduation on the rotating scale, is known as the SPEED INDEX The outer fixed scale is known as the MILE SCALE and the inner rotating scale the TIME SCALE.