Air Safety-Mercy Flights

In the post war era an unwritten policy was adopted under which pilots of Flying Doctor and aerial ambulance aircraft were allowed to “bend the rules” at their discretion, on night and bad weather flying, to save the life of a gravely ill patient. For their part, the Department of Civil Aviation’s ground facilities and communication networks would provide all possible assistance to pilots during such flights.

This was the situation that applied at Derby, Western Australia, on February 4 1956, where MacRobertson Miller Airlines conducted the area’s aerial medical service flying in an ex RAAF Avro Anson, VH-MMG, under contract to the local Flying Doctor base.

Three days before, the infant daughter of the manager of Tableland Station, on the Kimberley Plateau, 212nm (393km) almost due east of Derby, had become seriously ill. Despite treatment prescribed for her via the Flying Doctor radio network, she became worse and on February 3 it was arranged to fly her to Derby for admission to hospital. But before the MMA Anson could leave Derby to pick her up, another radio call from Tableland Station reported she had suddenly improved, and the flight was cancelled.

However, about mid afternoon the following day, Saturday, February 4 1956, a further radio consultation indicated she had relapsed and the doctor on duty at Derby felt she should now be transferred to hospital as soon as possible. MMA pilot Pieter van Emmerik, on temporary transfer from Perth to handle the Derby base’s medical flights, was called upon to make the trip.

On the Saturday afternoon when the call came to make the emergency flight to Tableland Station, van Emmerik was looking forward to returning to his home in Perth the next day to celebrate his 11th wedding anniversary. Since his secondment to Derby the previous month, he had been extremely busy, only that morning completing the return leg of an overnight trip to Darwin as first officer on a MMA DC-3. It was in fact his 12th day on duty without a break, DCA having granted MMA a concession for him to exceed his flight time limitations because he was the only experienced company pilot available for the Derby base duties.

At 4.25pm, with Nursing Sisters Frances Day and Helen Newman from the Derby hospital on board Anson VH-MMG, van Emmerik took off for Tableland Station. The weather forecast was for five eighths of large cumulus cloud at 5000 feet (1525m), 2000 feet (610m) above the highest terrain enroute, with isolated thunderstorms, 18nm (24km) of visibility, and a wind of 14 knots (26km/h) from the southeast.

Radio communications with the Anson were poor because of high atmospheric noise on the HF frequencies in use, and the ex USAF radio equipment fitted to the Anson was not noted for its reliability. But the one hour 50 minute flight from Derby to Tableland Station in hot and humid conditions was uneventful, apart from thermal turbulence, and the aircraft landed there just on sunset at 6.14pm.

After the nursing sisters had examined the small patient, she was placed aboard the Anson. Her station manager father was accompanying her to Derby in the aircraft, and together with his luggage, he also loaded a quantity of freshly killed beef and some fruit from the homestead orchard, evidently intended as gifts for business colleagues in Derby.

As soon as the Anson crew had refreshed themselves with cool drinks, they boarded the aircraft again and, at 6.32pm in the gathering dusk, the aircraft took off into the east, turned downwind and set course into the west for Derby.

Although the weather was still fine at Tableland, a station hand watching the Anson’s departure from the homestead could see that an intense electrical storm lay across the aircraft’s track in the far distance to the west.

At 6.34pm van Emmerik contacted Wyndham Aeradio (later Flight Service) to pass his departure report, advising that the return flight to Derby would take an hour and 40 minutes. Although another aircraft heard the Anson reporting about half an hour later, and the Aeradio operator at Wyndham believed he heard it, though with some difficulty in the heavy static, Broome Aeradio received no further transmissions from the Anson and it subsequently failed to arrive at Derby.

An air search began the following morning, initially with a RAAF Avro Lincoln from Darwin and a MMA DC-3. Meanwhile numbers of reports from homesteads in the sparsely settled area poured into Derby via the Flying Doctor radio network, the majority of which seemed to indicate that the Anson had diverted to the north of its track towards Wyndham.

It was also determined that a line of intense thunderstorms, associated with the inter tropic front, had developed after sunset over the King Leopold Ranges right in the path of the aircraft’s homeward track. This local deterioration in the weather, unknown at the time to the DCA radio communication network, could explain the apparent diversion towards the lower terrain of the Wyndham area. On the second day of the search, now being supplemented by two more RAAF Lincolns and a Dakota, as well as two DCA DC-3s, the available aircraft were divided, some searching along the planned track, and others in the Wyndham area.

Even more search aircraft were chartered and, because further questioning of those who had reported sightings now seemed to confirm that the Anson had diverted towards Wyndham at some point during its flight, the search was concentrated in the Wyndham area on the third and fourth days. Meanwhile, ground parties from the RAAF, DCA and the police were attempting to investigate each of the sighting and hearing reports in detail.

Towards the end of the fourth day, hopes were unexpectedly raised when a carrier wave, with the characteristics of the Anson’s transmitter, was intercepted by Aeradio stations throughout Australia. The signal was intermittent, with short, unintelligible bursts of keying. Hasty attempts to obtain a bearing on the signal by stations equipped with HF Direction Finders indicated the probable source of the signal was the area around Wyndham. Were there survivors with the downed Anson? Were they trying to attract the attention of the search effort?

For the next three days all available aircraft searched the entire area of probability, based on the distance the Anson could have flown from Tableland Station with the fuel on board. Meanwhile, all possible efforts were made to track down the mystery signal. But hopes were finally dashed when, by generating a signal from an identical transmitter in another Avro Anson operating in the area of probability, it was established beyond doubt that the mystery signal could not have come from the missing aircraft.

Eight days had now passed, during which the search crews had been subjected to intense, concentrated all day flying in what was becoming one of the biggest air searches ever undertaken in Australia. It was therefore decided to rest the crews for a day while the search coordinators reviewed all available findings.

This established that, of all the sighting and hearing reports, only one from Mt House homestead about halfway between Tableland and Derby could really be regarded as authentic.

A reasonably intact Avro Anson was clearly nowhere within the area of probability, so the search effort would now be concentrated on the planned track between Mt House and Derby itself which, except for the final 30nm (56km/h), lay over the wild and rugged King Leopold Ranges.

Carried out by RAAF Lincolns on the 10th day of the search, this was also abortive, the crews afterwards reporting that the speed of the Lincolns made it difficult to sight any wreckage lying in the deep valleys. As a result the RAAF aircraft were withdrawn from the search operation and it was decided instead to base a fleet of light aircraft, together with the two DCA DC-3s, supported by ground parties with radio equipped Land Rovers, at Glenroy, close to the eastern side of the King Leopold Ranges some 50nm (95km) west of Tableland.

But after only one aircraft, a Percival Proctor, had arrived at Glenroy, a deep cyclonic depression moved in from the coast, saturating the whole Kimberleys region with heavy rain for the following six days, marooning the advance party at Glenroy, and flooding the Glenroy aerodrome.

On February 22, two days after the search was finally able to resume and 18 days after the Anson had vanished the disintegrated remains of the aircraft were at last sighted from the air. The partially obscured wreckage was lying in flooded country a few miles north of its planned track near Hawkestone Peak, in the foothills of the King Leopold Ranges.

Although the crash site was less than 15nm (30km) by air from Kimberley Downs Station, access to it by ground party proved extremely difficult. Three flooded rivers had to be crossed, and most of the surrounding countryside was covered in water. A party, equipped with inflatable dinghies, that set out from Kimberley Downs, took two and a half days just to reach the crash site. But other than confirming that there was no possibility that anyone on board the Anson could have survived, there was little they could do the impact point itself and some of the wreckage was still submerged by floodwaters.

Any further attempt to investigate the accident was impossible until after the end of the wet season a month later when, on April 23, DCA air safety investigators from Perth, guided by an Aboriginal tracker and accompanied by a senior ground engineer from MMA and two police constables, again set out for the crash site. They reached it the next day and spent the following three days there examining the wreckage.

They found the Anson had virtually disintegrated on impact. The wreckage was confined to a small area, and it was evident from impact marks, wreckage distribution and the extent of the damage that the Anson had dived almost vertically into the ground at high speed, with both engines under power. All airframe components were accounted for in the wreckage, suggesting the aircraft had not broken up in flight. But because of the degree of damage sustained, it was impossible to determine if the aircraft’s control systems were fully functional at moment of impact.

Though equipped with a conventional Sperry instrument flying panel, including directional gyro, artificial horizon and vertical speed indicator, and a manually cranked radio compass loop for use with the aircraft’s low frequency receiver, the Anson did not meet the Department’s requirements for operations under instrument flight rules, having neither duplicated pitot-static and gyroscopic instruments, nor adequate radio navigation aids. It was also found that, because the Anson had been chartered earlier by the BHP company for a scintillometer survey of radioactivity, it had been fitted with non luminous instrument dials to avoid spurious survey readings.

The investigators could only conclude that extreme turbulence in the tropical thunderstorm that developed over the King Leopold Ranges on the night of the accident, which subsequent weather reports showed to be of exceptional severity, had led to a loss of control of the aircraft. Extremely heavy rain, possibly causing erratic instrument readings, and the temporary blinding effect of lightning in the pitch black flying conditions, could have contributed to the loss of control.

During the ground party’s examination of the crash site, a number of trees in the vicinity were found to be uprooted, evidently by a severe storm, and it seemed probable that thisoccurred on the night of the accident.

DCA’s official finding on the cause of the accident was that the Anson “encountered a thunderstorm of such severity that control of the aircraft could not be maintained.”

No hint of criticism was levelled at van Emmerik’s decision to press on towards Derby in the deteriorating conditions. On the contrary, the then Director General of Civil Aviation, Mr D G (later Sir Donald) Anderson, in a memorandum to the Minister for Civil Aviation on the circumstances of the accident, wrote:

“… those living in the vicinity of the crash reported that the weather this night was the worst they could ever remember in the district. One can only admire the pilot’s perseverance in attempting this flight, and I am sure he would have been influenced by the condition of the sick child.”

Even so, the accident was to be a watershed for Flying Doctor operations throughout Australia.

Up to this time, DCA was very much inclined to leave decisions on night and marginal weather flying entirely to the Flying Doctor pilot concerned. As a result, all commercial pilots professionally engaged in aerial medical service operations had a great deal of discretion, and there were no questions asked, even if the regular clinic visits to outback centres took longer than scheduled and the aircraft had to fly back to its base in the dark after all the patients had finally been seen by the doctor. Indeed, this “flexibility” became almost the rule rather than the exception, being excused on the grounds that it was “medical work” even if the only “urgency” was that of economics and staff convenience!

But after Derby base’s accident all this changed. DCA cracked down hard, insisting that in future only genuine “mercy flights”, whose medical urgency could be fully substantiated by the doctor concerned, would be given latitude to operate “outside the rules”. And pilots would in future be required to provide DCA with a written report on each and every such mercy flight, detailing the full circumstances behind the decision to make the flight.

Thus the definition “Mercy Flight” and the specification of its operational conditions entered official civil aviation parlance.

Officially, that is the end of the story. But from information that has come to light in recent years primarily as a result of the efforts of Pieter van Emmerik’s now middle aged children to know more about the circumstances of their father’s crash and the whereabouts of his last resting place it seems that some events surrounding the accident remain shrouded in mystery.

It is said to have been common knowledge in the district at the time that van Emmerik was extremely reluctant to make the return flight to Derby on the night of the accident because of the threatening weather. According to local information, the child patient was not as ill as expected when examined by the nurses at Tableland Station, and van Emmerik wanted to remain overnight before returning to Derby, declaring that “it would be suicidal” to attempt the flight into the line of tropical thunderstorms developing over the aircraft’s return route. This was entirely in character with the pilot’s highly professional attitude to flying.

The two nurses made radio contact with medical staff at Derby via the local Flying Doctor base station and obtained agreement for this decision, the doctor on duty there being satisfied that, with the nursing care now available at Tableland Station, the child’s evacuation to hospital could be safely left until the morning.

So why did van Emmerik, despite this medical advice and the obviously deteriorating flying conditions over the route, decide to act so contrary to his sound professional aviation judgement?

Evidently the child’s station manager father had urgent business in Derby indeed it is claimed that this was the reason he had chosen to escort his daughter to Derby aboard the aircraft. A tall, massively built man, he is said to have subjected the pilot to great pressure to leave for Derby immediately, and van Emmerik was apparently persuaded against his better judgement to make the flight.

A particularly bizarre aspect of the matter is that the child’s father was evidently carrying a revolver on the aircraft.

There are other indications that the full story of this accident was never told. From this distance in time, one can only wonder if the fear of recriminations concerning the then shortcomings of aerial medical operations in general, and of this flight in particular, conditioned the thinking of those responsible for decisions made regarding the next of kin.

Footnote: The many airline accidents that, over the years, progressively evolved the superb airline industry Australians enjoy today, are chronicled in detail in Macarthur Job’s two books, Air Crash, Volumes 1 and 2, available from Aerospace Publications.

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