An attachment giving a number of accurate straight or curved climb or descent flight paths has been developed for use with the Australian-designed airborne distance measuring equipment (DME). The electrical output from a special altimeter is converted into a time delay which increases with altitude. In the DME distance is measured, fundamentally, in terms of a similar time delay. The h/d flight path is defined by keeping these two delays equal as the aircraft climbs or descends. The ILS glide slope meter is used as the pilot's path indicator. Nominal slopes from 1° to 6° may be selected. In terms of height, deviations from the path of ± 250 ft. produce full-scale deflections on the meter, while the maximum error is ± 1000 ft.