[Peetwo]

A two coffee read.

It has taken nearly 34 months to provide the ATSB report into:-


Collision with terrain following an engine power loss involving Cessna 172M, VH WTQ, 12 NM (22 km) north-west of Agnes Water, Queensland on 10 January 2017

It is a ‘long’ read and some of the details (below) are worthy of note. ATSB have made some serious efforts to establish why the engine failed when it did. That primary mystery remains unresolved, not from lack of effort on the ATSB part; I can’t think of much else they could have done. Even a simulation would not be able to duplicate the exact circumstances to determine if some weird ‘air-lock’ due to un-porting of a fuel feed had occurred would not provide definitive answers to the puzzle (IMO). So why the engine failed, when it did will remain unexplained. However, there are some salutary lessons to be learned from the detailed investigation.

There are some things which (again IMO) could have been done better by the operator. For example, the beach inspection protocols. Anyone who has flown ‘in-the-bush’ the real thing, knows how difficult it is to even spot (stationary) livestock on an ALA from much above 3/400 ft; below that objects become much clearer, so there is an identified ‘requirement’ to get ‘low and slow’. How low and how slow is difficult to define – in terms which could be realistically transposed into SOP.

ATSB. - The pilot of the accident flight reported that he normally conducted airborne inspections of Middle Island ALA at 150–200 ft. A review of the GPS data identified 19 previous inspections of Middle Island ALA, all of which were conducted by the pilot of the accident flight. The lowest altitudes recorded during these inspections were generally below 100 ft with a median value of about 60 ft (see Review of airborne inspections at Middle Island ALA ). Given the relatively constant descents and straight flight paths involved in these inspections, the GPS data was probably within the GPS manufacturer’s expected level of accuracy.

ATSB. - Overall, the ATSB concluded that the altitude at the time of the engine power loss was probably between 40 and 80 ft and therefore probably close to the GPS-based altitude of 60 ft.

ATSB. - The inspections were generally flown at 50–100 ft AMSL while flying at normal cruise speed towards an area of water at the end of the beach, with no planned consideration of what to do in the event of an emergency.

Valid points – there was a requirement for almost a 180˚ reversal around the headland to land into wind. Ref Fig 2. With 150 or 160 feet on the clock, would there have been a better outcome? With a little less speed and a handful of flap, could the outcome have been less damaging? I wonder, had there been a little less ‘thrill’ for passengers and a little more conservative thinking been applied, could the whole accident have been avoided. I don’t know; would I be flat chat, flapless, at 60 feet over a beach, with a reversal to follow – I don’t think so. This is the sort of ‘stuff’ that needs to written into an Ops Manual – company SOP. Murphey is everyman’s co-pilot and anything that can be done to keep his mucky paws out of the equation should be done.


Engine mystery.

The engine sustained a sudden and total power loss. The engine/propeller speed immediately reduced and then gradually decreased for the remainder of the flight (see Audio analysis of the engine/propeller speed).

ATSB - Despite a detailed inspection of the engine and related systems, the ATSB was unable to identify the reason for the loss of engine power.

ATSB - During the period immediately prior to the engine power loss, the indicated fuel quantity was about one quarter full on the left tank gauge and slightly above half full on the right tank gauge.

ATSB - Based on an hour meter reading documented in maintenance worksheets on 12 November 2015, the flight time documented on the maintenance releases underestimated the actual flight time by 62.2 hours (or about 40 per cent) during the period from the periodic inspection on 1 May 2015 to the next periodic inspection on 12 November 2015.

ATSB - There were multiple days on which flights were recorded on the aircraft’s GPS unit and/or the pilot of the accident flight had included flights in VH-WTQ in his logbook, but there was no certification on the maintenance release stating that a daily inspection or flights had been conducted (see Appendix A).

ATSB - Prior to the sudden engine power loss at 1037:34, the only anomaly in the engine/propeller sound during the flight occurred at 1036:13, when there was a momentary reduction of engine/propeller speed before it recovered to its normal setting. This occurred during a rapid though brief pitch-down manoeuvre. The brief reduction in power appeared to be consistent with what would expected with the normal operation of the carburettor in such a manoeuvre and would have had no long-term effect.

The Go-Pro puzzle.

ATSB - Given the high degree of potential importance as evidence, an extensive search of the accident site for the GoPro cameras was conducted by the ATSB, police and state emergency service volunteers. That search did not locate either of the missing cameras.

ATSB - The reason why there was no memory card in the black-handled GoPro camera could not be determined, and the yellow-handled camera was never located

All food for serious thought; not the slightest bit of comfort for those grieving or hurt, but that is not the ATSB’s role. Despite the delay in the report being released, it is not too shabby an effort to define what went wrong. The only criticism I would gently make is that there is no advice provided, to prevent a reoccurrence; or, guidelines for Chief pilot’s to work with to set some minimum guidelines for pilots who need to make low level strip inspections.

Anyway, FWIW that’s all I can glean from the ATSB report, which is almost, but not quite up to world standard.

Toot - toot.

Just a note...the prec search & landing technique I was taught was thus:

Fly the upwind leg parallel to the runway, off to the side, with 1 stage flap and gear down, flying at 500 feet and 75 knots (depending on the aircraft - in a Cessna 172, that sounds about right).
Continue in that configuration and fly a 500 foot circuit.
After turning final, once again, offset from the runway (but closer), descend to 250 feet and fly a second pass then climb back to 500 feet for another circuit.
After turning final again, descend to 50 feet just off the centreline, fly a third pass, then climb back to 500 feet for another circuit, whereupon you perform a short field landing.

The first pass is to inspect the general condition of the field, the second is to time the length of the proposed runway, and the third is for closer inspection.

Missed the (above) CW post (busy scribbling) : nevertheless, it raises some interesting points. Clearly, the prescription offered has been SOP for an operator. Perhaps not an operator who ‘routinely’ needs to make a ‘strip inspection’ when (importantly for this event) a ‘strip report’ is not provided. Scheduled services, such as ‘mail runs’ require that should a strip report not be available, then the pilot is required to conduct an assessment – prior to landing. SOP, (how to) writ in stone. Fair and reasonable stuff.

While I doubt the ‘practical’ value in the procedure described; it is at least a ‘SOP’ based on previous, though limited experience of ALA operations.

The operation being examined differs in one respect – it was a beach landing. This, believe it or not, is not a task for the ‘inexperienced’. In fact, I’d go as far as to say it is a unique ‘skill set’ which demands careful and extensive training. There is a need to ‘get down’ close and personal with ‘the beach’ for things may have changed; such as the slope of the beach, or even the reliability of the surface. To see the changes, one must get a little lower than 500’ and, importantly, one must be able to ‘read’ those changes as they can affect to landing.

Specialised operations require, no demand, clearly defined SOP and training. No doubt the accident pilot was experienced in such operations; but, was the operation conducted within the restraints of ‘sensible’ stated operating policy? It leaves two questions begging answers.

Did CASA approve/ accept the ‘operating policy? Was the accident pilot in compliance with that policy? You may even ask, “was there a policy?” If not, why not? Where was our watch-dog?

Cheers CW. Thought provoking appreciated.

P9 – “ATSB - During the period immediately prior to the engine power loss, the indicated fuel quantity was about one quarter full on the left tank gauge and slightly above half full on the right tank gauge.”

Not being ‘familiar’ with the type, that statement of fact puzzles me. Assumptions are in order here. (i) the operators stated policy on re-fuel seems to indicate that there would be an almost equal quantity of fuel in each tank. (ii) The stated operational policy was to operate with a ‘fuel feed’ from both tanks. (iii) It would, from dim, distant memory seem sensible to manage the fuel supply in such a way as to ‘balance’, within the limitations of the fuel gauges, the quantity in each tank: just common sense.

Why was the quarter tank discrepancy mentioned in the ATSB report?

Sure, it was based on the best information available to ATSB; and, in all probability, has bugger all to do with the engine quitting – but it is a part of the ‘mystery’.

Too many decades have gone by since my days in single engine Cessna aircraft for memory reliability; however, I can’t recall any warning about an ‘unbalanced’ fuel load leading to engine failure.  But, it seems to be out of ‘consistency’ with either operating practice or normal system function. No idea, except it sticks out; awkward like. No doubt ATSB covered it off, just seemed “passing strange” to my addled old head.

Yes boy, shut up and sup up is a good ideal; adopted instanter.  Cheers.

Update: Via Ironsider yesterday in the Oz.

---

CASA urged to mandate upper torso restraints

Operators of light aircraft could be ordered to fit upper torso restraints to passenger seats after an investigation into a fatal charter flight crash at Agnes Water in January 2017.

A British backpacker was killed in the crash, and three other people including the pilot suffered serious injuries when the Cessna 172 suddenly lost engine power while conducting a low-level beach inspection.

A 2½-year investigation by the Australian Transport Safety Bureau was unable to explain the sudden loss of engine power but identified a number of problems with the operator’s activities.

These included a lack of training or procedures to manage the risk of engine failure at low height. Other issues identified by the ATSB were poor documentation of flight hours, unsecured baggage, no life jackets on board and the conduct of near-aerobatic manoeuvres during passenger charter flights with limited controls in place.

Shortly after the crash, the Civil Aviaton Safety Authority cancelled the licence of pilot Les Woodall, and that of charter operator Bruce Rhoades, as well as the air operator’s certificate for Wyndham Aviation.

Mr Woodall launched legal action against CASA and was allowed to reapply for his licence, then last year, the terminally ill Mr Rhoades mounted a public campaign to clear his name, accusing the regulator of a substandard investigation.

He passed away last month without seeing the ATSB’s final report on the crash.

Although the loss of engine power was a mystery, the report found that had the Cessna’s seats been fitted with upper torso restraints in addition to compulsory lap belts, passengers’ injuries would have likely been less severe.

“As a consequence, the ATSB recommends that CASA consider mandating the fitment of upper torso restraints for all seats in small aeroplanes and helicopters,” said ATSB chief commissioner Greg Hood.

“The recommendation is particularly aimed at those aircraft being used for air transport operations.”

CASA was considering the recommendation.

---

For those interested here are the SRs issued by the ATCB and addressed to CASA:

Regulatory surveillance – scoping of surveillance : events https://www.atsb.gov.au/publications/inv...005-si-08/

Safety issue description

The Civil Aviation Safety Authority’s procedures and guidance for scoping a surveillance event included several important aspects, but it did not formally include the nature of the operator’s activities, the inherent threats or hazards associated with those activities, and the risk controls that were important for managing those threats or hazards.

Response by the Civil Aviation Safety Authority:

In August 2019, in response to the draft ATSB report, the Civil Aviation Safety Authority (CASA) stated:

CASA, as a regulator, has the ability to help ensure that an operator complies with aviation safety regulations and operations manual procedures through ongoing surveillance. Both CASA’s records and the draft [ATSB] report indicate that CASA had identified issues with the operator which were addressed (at least in terms of operations manual procedures).

However, the effectiveness of CASA’s system of regulatory surveillance and auditing in ensuring safety is based on the assumption that operators are genuinely interested in, and meaningfully committed to, compliance. What appears to have occurred in this case is that Wyndham Aviation had developed a culture of wilful, or at least habitual, non-compliance with both the safety regulations and the requirements of the Wyndham Aviation operations manual.

CASA has a robust entry control and oversight system which is continually under review and in this case additional or different oversight is unlikely to have significantly impacted the attitudes and behaviours of the operator.

ATSB comment:

The ATSB notes that CASA has advised that it continually reviews its entry control and oversight system. However, the ATSB is concerned that CASA has not outlined any specific safety action to address this safety issue, nor has it undertaken any apparent safety action to effectively address a similar safety issue released in November 2017 (AO-2014-190-SI-14). Accordingly, the ATSB issues the following recommendation.

Recommendation

The Australian Transport Safety Bureau recommends that the Civil Aviation Safety Authority undertake further work to improve its procedures and guidance for scoping surveillance activities to formally include the nature of the operator’s activities, the inherent threats or hazards associated with those activities, and the risk controls that were important for managing those threats or hazards.

Requirements for upper torso restraints in small aircraft : https://www.atsb.gov.au/publications/inv...005-si-06/

Recommendation

The Australian Transport Safety Bureau recommends that the Civil Aviation Safety Authority consider mandating the fitment of upper torso restraints (UTRs) for all seats in small aeroplanes and helicopters, particularly for those aircraft (a) being used for air transport operations and/or (b) for those aircraft where the aircraft manufacturer has issued a mandatory service bulletin to fit UTRs for all seats (or such restraints are readily available and relatively easy to install).

ATSB safety advisory notice to all operators of small aeroplanes and helicopters
Action number: AO-2017-005-SAN-028

The Australian Transport Safety Bureau strongly encourages operators and owners of small aeroplanes manufactured before December 1986 and helicopters manufactured before September 1992 to fit upper torso restraints to all seats in their aircraft (if they are not already fitted).

MTF...P2