Duck-under and other deadly sins
By Johan Lottering
MOST tragic about the Lear 36 accident which claimed high-profile Christian leaders Dr. Myles Munroe, his wife Ruth, daughter and six occupants on Nov. 9, 2014 was the preventable nature. Failings in the safety system had evidently let them down. The aircraft hit a crane on the second consecutive approach in heavy rain to land at Freeport Airport on Grand Bahamas, the northernmost island in the Bahamas group.
Performance pressure on the pilots, albeit indirect or self-induced, may well have played a role in their decision-making, considering that another commercial airliner was believed to have diverted due to bad weather shortly before. Dr. Munroe, international motivational speaker and author of several best-selling books, was scheduled to be the main speaker at a Global Leadership summit. His ill-fated business jet had departed from Nassau, one of the main islands in the Bahamas group, barely an hour before. The legal two hours' fuel endurance requirement may well have weighed heavily on the reputably extremely 'safety conscious' crew. The Lear 36, later variant of the 35, has added fuel endurance. But, the two hours reserve requirement, would nevertheless add to pressure on pilots flying to islands and isolated destinations.
However, an incident report lodged in January after a narrow escape from death during an approach for the same Runway 06, lodged by the crew of a freight twin turboprop, has come to light. The report had highlighted a pre-existing problem with shipyard cranes. Yet, when looking at the Munroe accident holistically the old sin of 'duck-under' on the part of crews at or before approach minimums, cannot be ruled out entirely by investigators. The more detailed narrative of the earlier incident report [no. 114092 on p. 45] can be found via the Internet link
The freight aircraft had to take evasive action on final approach to avoid colliding with a ship-mounted crane, missing by a mere 200 feet vertically and 1, 000 feet horizontally. The report cited the following contributory human factors:
ō Situational awareness [lack thereof]
ō Communications breakdown - essentially on the part of Air Traffic Control [ATC].
ATC or Terminal Radar Area Control [Tracon] is only incumbent with vertical separation of an aircraft with obstacles and terrain if under Instrument Flight Rules, 'radar identified' and 'under radar control' - regardless of prevailing 'partial' or 'marginal' Visual Meteorological Conditions [VMC]. Further scrutiny would highlight pre-existing problems such as an area chart for Freeport International Airport indicating cranes 364 and 351 feet high on the extended centre line of Runway 06. According to an incident report in Jan. 2014 on the NASA Aviation Safety Reporting System [ASRS} six cranes are referred to in Notams. The map depicts three to the southwest. One crane's location concides with the 'step-down point' for the VIR 'Y" Approach, at 620 feet and 3.2 DME. [Statistically multiple step-down approaches present the highest risk].
The NASA incident report had highlighted other contributory factors like unserviceable surface weather reporting frequency and Precision Approach Path Indicator [PAPI] lights at the time. Months later the ill-fated Lear 36 would strike a crane at approximately four miles inbound. A typical [continuous] three degree approach slope would place an aircraft at 1, 200 feet above ground level [a.g.l.] at the collision point - adequate, though somewhat too close for comfort. The 'powers that be' may have to consider alternatives, such as a DME Arc approaches, notwithstanding relative complexity to pilots. As accident aetiologies invariably expose multiple causal factors culminating into one event, prudent crews would do well to extract analogies from report no. 8894, on the SACAA website.
"A PC-12/47 was approaching from the seaward side in overcast conditions for Plettenberg Bay Aerodrome on Feb. 8, 2011. Earlier that afternoon it had taken the crew of a Cessna Citation two attempts to land in [still prevailing] difficult weather conditions, compounded by only non-precision NDB approach facilities being available. All nine aboard the PC-12/47 were killed as a result of the crew losing both positional and situational awareness later that same day, the aircraft having descended below the minimum safe [non-precision] approach slope. The respective PC-12 and Lear 36 accidents would be classifiable under the 'Controlled Flight Into-Terrain' [CFIT] accident category, in the 'Approach to Land' or 'ALA' phase'. NASA also keeps track of 'Controlled Flight Towards Terrain' [CFTT] incidents. Safety information from incidents is supposed to prevent accidents."
" Self-induced and [perceived] client-imposed pressures often compel crews to take shortcuts, or 'pressing on' when they should rather delay or divert in the face of a combination of environmental and operational facts rendering continued operations either 'marginal' or unsafe. In Africa 'Part 135' denotes 'non-scheduled' or 'charter' operations, implying flexibility. The inherent nature may lend itself to undue demands and even unreasonable expectations by clients [though fingers are not being pointed to anyone in particular]. Significantly, the American FAA refers to 'On Demand' operations."
Proper planning and good judgement often end up on the altar of 'eagerness to please'. As in Corporate, albeit Part 91 'Private' Operations, the 'locus of control' may resort with the MD or VIP in the cabin and not entirely on the flight deck, with crew. Anything with two heads is a monster. Crews and clients alike ought to take heed. The Munroe crash may well be a reminder that the relevant importance of any schedule, meeting or event should always be made subject to safe environmental, crew capacity [fatigue], aircraft technical and operational conditions. So, be careful out there!
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