"Aviation is not inherently dangerous, but to an even greater degree than the sea, it is terribly unforgiving of any carelessness, incapacity or neglect"...
- Unknown author
Flying conditions in Australia, when compared to many other parts of the world, are generally very favourable, with such phenomena as gales, blizzards
But severe weather is not the only way to produce hazardous flying conditions.
In light southerly winds, when the moisture content of the atmosphere is high,
low cloud – called stratus - often drifts in from the ocean across southern Victoria, and can cover extensive areas of the state, often as far north as the Great Dividing Range.
Around Melbourne, because of the comparatively flat terrain, it is usually safe to fly under this cloud, but over in the eastern areas, lie the Dandenong Ranges, and these are often covered in stratus during periods of moist southerly winds. As long as the pilot is accurately aware of the aircraft’s position, encountering cloud-covered terrain should never be an issue. But in the event of a navigational error it becomes a very different story.
Following the loss of the Southern Cloud in 1931, in which lack of communications played a crucial role, two-way radio was progressively installed in passenger carrying aircraft, and this quickly proved itself a real safety contribution.
However for the remainder of the 1930’s, passenger aircraft were still navigated by using manual techniques of estimating ground speed, noting reporting points and maintaining a navigation log, a process that became difficult at night or in thick cloud cover. Unlike the situation today, where pilots are aware of their height, location and speed to within an almost precise accuracy, the manual navigation process usually produced a certain amount of error, depending on the skill and experience of the Captain and First Officer.
But for Captain A. C. Webb and his crew, navigational issues were probably far from their minds as they climbed aboard their aircraft on Tuesday 25th October 1938, for a routine passenger flight Melbourne to Adelaide and return. They were flying the Kyeema, an Australian National Airways DC2, with the call-sign VH- UYC.
During the 1930’s, the DC2 was a thoroughly modern aircraft. Built by the Douglas Corporation and released in 1933, it was an instant hit with airline companies because of its superior performance and carrying capacity. Powered by two Wright Cyclone engines, each pumping out 875 horsepower, it could carry a crew of three along with fourteen passengers at 320 kph to a height of 6500 metres and over a range of 1600 km. This was a quantum leap forward from the old Stinsons and Avro 10’s of only a few years before.
A DC-2 in flight
(Image: Wikipedia Commons)
The DC2 was the first Douglas aircraft to be purchased by an overseas airline and in 1934 the Dutch company KLM entered one of its DC2’s in the London to Melbourne Air Race. In an astonishing performance, as it raced, it also completed its normal tasks of picking up mail and passengers and ended up flying more than 1600 km further than the race route. It finished second, behind a “one off” specially produced racing aeroplane, in what turned out to be a tremendous promotion for the Douglas Corporation.
The flight undertaken by Webb and his crew, from Melbourne to Adelaide and back, was only a short hop in comparison, and easily within the capabilities of the DC 2. The first leg began with an early morning take off from Melbourne, and proceeded routinely, with the aircraft landing about two and a half hours later at Adelaide.
Flying conditions were generally ideal, although a light southerly wind had produced extensive cloud-cover across the Melbourne basin, extending from the central business district across the eastern suburbs and over the Dandenong Ranges to the east. The base of this cloud – classical stratus formation - was around 450 metres but with lower patches around 250 metres – well above most elevations around Melbourne, but below extensive parts of the Dandenong Ranges which reach above 500 metres. These areas were in cloud for most of the day, under the influence of the cool southerly winds.
After taking aboard fourteen new passengers in Adelaide, the Kyeema turned around, took off on schedule and headed back towards Melbourne, in weather conditions that remained favourable for flying.
Amongst the newly arrived passengers were some notable citizens, including a Member of Parliament, Mr. Charles Hawker, MHR, the noted vigneron, Mr. Johann Gramp who was the managing director of Orlando Wines and the eminent barrister Mr. Leonard Abrahams KC. Also aboard were a honeymoon couple, Hans and Stella Gloe.
The Honourable Mr. Charles Hawker MHR (Image: Wikipedia Commons)
Soon after 1.30 pm Melbourne time, a transmission from Kyeema was received at Essendon Airport, confirming that the aircraft was passing over Daylesford, and about to enter cloud as it began its descent into Melbourne. The estimated time of arrival at Essendon was 1.45 pm. However, after another brief transmission from Kyeema, nothing further was heard, and when the aircraft had not arrived by 2 pm, the authorities became concerned.
In the meantime, near the top of cloud-covered Mount Dandenong, about 32 km to the east of Essendon Airport, two workers were clearing undergrowth from around a roadway. Macarthur Job, in his publication “Air Crash 1” recorded the events as they unfolded:
“In the eerie quietness of the fog enshrouded bush, both men gradually became aware of the distant whine of an aeroplane; the sound was coming from the west, roughly in the direction of Melbourne. And it seemed to be getting louder…. It was a big one all right and it was getting nearer and nearer all the time! The noise continued to grow in intensity; it wasn’t just a whine now. They could hear the powerful throb of the engines as well.
Suddenly, the noise of the engines and propellers was overlaid by a loud screeching; an instant later there was a sickening smashing of metal, then came a tremendous explosion which shook the ground beneath their feet…and a deathly silence”. The Kyeema had flown straight into Mount Corhanwarrabul, close to the main peak of Mount Dandenong.
The summit of Mount Corhanwarrabul. The Kyeema smashed into this peak about 50 metres from the top where the television mast now stands. (Image from Wikipedia Commons)
It was quickly established that all eighteen people aboard had been killed, and an official enquiry was convened at Melbourne’s Exhibition Buildings only three days after the disaster. This had been ordered by the Minister for Defence, Mr. Harold Thorby, as both civil and military aviation then operated under the auspices of the Defence Department.
After detailed deliberations, the inquiry found that the first cause of the disaster was inaccurate navigation. The investigators concluded that Captain Webb and his crew had failed to keep an accurate navigational log, which required them to monitor the speed of the aircraft and note when certain reporting points had been reached. As a result they had probably mistaken Sunbury for Daylesford (they looked similar from above) and were therefore about 32 km nearer Melbourne than they believed when commencing their descent into the deck of stratus.
As Kyeema descended in the overcast, Captain Webb believed he should emerge from the cloud base at around 1.45 pm near Essendon Airport. In fact he had actually flown well past Essendon, invisible below the cloud, and had descended straight into Mount Corhanwarrabul, about 32 km to the east.
The Kyeema overshot Essendon Airport and descended into Mount Corhanwarrabul
Although this represented a gross navigational error, it was also recognised that existing technology could have helped avoid this situation. Radio beacons were already available that provided pilots with a definite course along which to fly, and also enabled an accurate locational “fix” to be obtained.
The public were surprised to learn that a high frequency radio beacon had been installed at Essendon Airport some 18 months before the accident, but had never been made operational. Several experts afterwards claimed that this device, in fully functioning mode, would have prevented the accident.
As a result of the Kyeema disaster, a system of these beacons was installed along the main inter capital city routes, providing pilots with instant and accurate navigational advice.
Another major change that followed was the appointment of so called “Flight Checking Officers” whose job it was to maintain a watch on the progress of flights on the main air routes. This “double check” was to guard against a pilot making a navigational error, as had happened with the Kyeema.
And, in another major change, the Australian aviation governing body, the Civil Aviation Board, part of the Department of Defence, was replaced with the Department of Civil Aviation or DCA.
The Kyeema disaster is now recognised as one of the watershed events of Australian aviation, generating a whole raft of changes that produced a major increase in safety to flying in Australia.
On October 25th 1978, the 40th anniversary of the disaster, a memorial plaque was placed on a cairn beside the roadway some 50 metres above the crash site.
The memorial cairn erected in 1978 close to the actual crash site. (Image from Wikipedia Commons)
Engraved on the plaque is the following text:
FIFTY METRES BELOW THIS POINT ON 25 OCT 1938 AUSTRALIAN NATIONAL AIRWAYS DC-2 ‘KYEEMA’ PLUNGED TO DESTRUCTION WHILE THE MOUNTAIN WAS ENVELOPED IN CLOUD. ALL 18 PERSONS ON BOARD PERISHED.
FROM THE RECOMMENDATIONS OF THE SUBSEQUENT ENQUIRY HAVE EVOLVED THE AIR TRAFFIC CONTROL SYSTEMS IN USE THROUGHOUT AUSTRALIA TODAY.
THIS PLAQUE, PLACED BY THE MOUNT DANDENONG HISTORICAL SOCIETY WITH ASSISTANCE FROM O. GRAMP & SONS, THOS. HARDY & SONS, S. SMITH & SON, AUSTRALIAN FEDERATION OF AIR PILOTS AND FORESTS COMMISSION OF VICTORIA WAS UNVEILED ON 25 OCT 1978 TO MARK THE 40th ANNIVERSARY OF THE DISASTER.
This memorial reminds us of the price we have had to pay for safe flying in Australia – as well as the ever-present need for accurate navigation in all airline operations.
Reference: "The Complete Book of Australian Weather", Richard Whitaker, Allen and Unwin, 2010
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