The RNAV is a breeze with the right gear, ala moving map, autopilot combined with glide slope information, etc, but for those without that type of gear,those that are stuck with the first generation type RNAV approved GPS’s it is not so easy, And there is a lot of aircraft out there that still have that type of equipment.
For those who reckon this approach is just fine and beaut without any significantly higher workload than other approaches, here is a little cut and past paste (of that that refers to the RNAV approach) from the findings.
(Scource: ATSB 200501977)
The Lockhart River Runway 12 RNAV (GNSS) approach probably
created higher pilot workload and reduced position situational awareness
for the crew compared with most other instrument approaches. This was
due to the lack of distance referencing to the missed approach point
throughout the approach, and the longer than optimum final approach
segment with three altitude limiting steps.
Based on the available evidence, the Lockhart River Runway 12 RNAV
(GNSS) approach design resulted in mode 2A ground proximity warning
system alerts and warnings when flown on the recommended profile or at
the segment minimum safe altitudes. (Safety Issue)
The Australian convention for waypoint names in RNAV (GNSS)
approaches did not maximise the ability to discriminate between waypoint
names on the aircraft global positioning system display and/or on the
approach chart. (Safety Issue)
There were several design aspects of the Jeppesen RNAV (GNSS)
approach charts that could lead to pilot confusion or reduction in
situational awareness. These included limited reference regarding the
‘distance to run’ to the missed approach point, mismatches in the vertical
alignment of the plan-view and profile-view on charts such as that for the
Lockhart River runway 12 approach, use of the same font size and type for
waypoint names and ‘NM’ [nautical miles], and not depicting the offset in
degrees between the final approach track and the runway centreline.
Jeppesen instrument approach charts depicted coloured contours on the
plan-view of approach charts based on the maximum height of terrain
relative to the airfield only, rather than also considering terrain that
increases the final approach or missed approach procedure gradient to be
steeper than the optimum. Jeppesen instrument approach charts did not
depict the terrain profile on the profile-view although the segment
minimum safe altitudes were depicted. (Safety Issue)
Airservices Australia’s instrument approach charts did not depict the
terrain contours on the plan-view. They also did not depict the terrain
profile on the profile-view, although the segment minimum safe altitudes
were depicted. (Safety Issue)