Its interesting to see how many people propose ‘high tech’ solutions to the problems identified by this incident, but the use of LNAV / VNAV, Vert profile, GPS, etc, has many ‘gotch yers’ which start with a simple mistake or poor system knowledge. These systems represent increasing complexity in the modern world, which is often linked with higher workload, the need for wider knowledge, and much more crosschecking to avoid error and complacency.
The NDB 16 approach is a simple procedure; a 3 deg slope starting at 11.5 nm; in most respects just like a visual straight in. In IMC the visual cues have to be replaced with an electronic track – clearly depicted on an EFIS, and altitude checkpoints combined with vertical speed to confirm the required glidepath. Altitude checks can be made approximately every 30 sec (every nm @ 120kt GS). Thus the crew task is to use a scan pattern to include these aspects, together with airspeed etc to maintain safe flight. Crosschecks can be provided with timing, beacon crossing, comparison with the briefing (the plan), and the approach chart.
What could be easier; the modern jet transport has the latest display aids, further safety crosschecks provided by RNAV / GPS distance / position, and EGPWS terrain display, yet many of these aircraft get dangerously close to the ground short of the runway – see the link at #69.
Procedures remain simple (charts may need improvement) and aircraft are better equipped (safer), so why are these incidents still occurring? (The prevalence of events might be due to the identification and reporting from EGPWS data, another positive safety function of the system).
Some people cite that modern aircraft are more complex to operate (still simple to fly), but this complexity might be by choice where operators (management, even regulators) elect to use the high tech equipment without thinking about likely situations and consequences of error. In some circumstances it might be safer not to use the 'high tech' solution as the first choice (easier to fly, less opportunity for error), but still use it as a crosscheck.
Another variable involving people is the crew, the standards of training, professionalism, experience all appear to be changing and not necessarily for the better. These are the people who decide on the tactical use of the ‘high tech’ systems. They rely on a technical solution whereas some simple thought and preparation would provide a less complex and safer solution.
Perhaps its time to put people back into the flying loop (thinking and doing), which might improve airmanship and experience.