Air-tractor sledge
Encyclopedia
Sir Douglas Mawson's air-tractor sledge was a converted fixed-wing aircraft
taken on the 1911–14 Australasian Antarctic Expedition
, the first plane to be taken to the Antarctic
. Expedition leader Douglas Mawson
had planned to use the Vickers R.E.P. Type Monoplane
as a reconnaissance and search and rescue
tool, and to assist in publicity, but the aircraft crashed heavily during a test flight in Adelaide
, Australia, only two months before Mawson's scheduled departure date. The plane was nevertheless sent south with the expedition, after having been stripped of its wings and metal sheathing from the fuselage. Engineer Frank Bickerton
spent most of the 1912 winter working to convert it to a sledge, fashioning brakes from a pair of geological drills and a steering system from the plane's landing gear
. It was first tested on 15 November 1912 and subsequently assisted in laying depots for the summer sledging parties, but its use during the expedition was minimal.
Towing a train of four sledges, the air-tractor accompanied a party led by Bickerton to explore the area to the west of the expedition's base at Cape Denison
. The freezing conditions resulted in the jamming of the engine's pistons after just 10 miles (16.1 km), and the air-tractor was left behind. Some time later it was dragged back to Cape Denison, and its frame was left on the ice when the expedition returned home in 1913. In 2008 a team from the Mawson's Huts Foundation
began searching for the remains of the air-tractor sledge; a seat was found in 2009, and fragments of the tail assembly a year later.
The Mawson's Huts Foundation has undertaken extensive investigation using sophisticated equipment in 2009 and 2010. Results indicate that the air tractor, or parts of it, is still buried under 3m of ice where it was abandoned at Cape Denison.
had accompanied Ernest Shackleton
's 1907–09 British Antarctic Expedition
. Along with Edgeworth David
and Alistair Mackay
, he had been part of a man-hauled
sledging expedition, the first to reach the area of the South Magnetic Pole
. Upon his return from Antarctica, he recommenced to his post as geology lecturer at the University of Adelaide
. Despite an offer from Robert Falcon Scott
to join his Terra Nova Expedition
to reach the Geographic South Pole
, Mawson began planning his own Antarctic expedition. Mawson's plan, which led to the Australasian Antarctic Expedition
, envisaged three bases on the Antarctic continent, collectively surveying much of the coast directly south of Australia. He approached Shackleton, who not only approved of his plan but was prepared to lead the expedition himself. Although Shackleton withdrew from the expedition in December 1910, he continued to assist Mawson with publicity and fund-raising.
, Mawson mentioned his plans to Scott's wife Kathleen Scott
, an aircraft enthusiast. She recommended he take a monoplane
, and conveyed his interest to Lieutenant Hugh Evelyn Watkins of the Essex Regiment
. Watkins had connections with the ship and aircraft manufacturer Vickers Limited
, which had recently entered into a licence agreement to build and sell aircraft in Britain designed by the Frenchman Robert Esnault-Pelterie
. In a letter to Mawson on 18 May, Kathleen wrote:
On Kathleen Scott's advice, Mawson purchased a Vickers R.E.P. Type Monoplane
, one of only eight built. It was fitted with a five-cylinder R.E.P. engine developing 60 hp, and had a maximum range of 300 miles (482.8 km) at a cruising speed of 48 knots (26.1 m/s). Its wingspan was 47 feet (14.3 m), and its length 36 feet (11 m). The pilot used a joystick
for pitch and roll, with lateral control by wing warping
. Mawson opted for a two-seater version, in a tandem arrangement, with a spare ski undercarriage. The total bill, dated 17 August 1911, came to £
955 4s 8d. Mawson hired Watkins to fly the plane, and Frank Bickerton
to accompany as engineer. After Vickers tested the aircraft at Dartford
and Brooklands
, P&O
shipped the plane to Adelaide aboard the steamship Macedonia, at half the usual rate of freight.
in Adelaide. During a test flight the day before, excessive pressure in the fuel tank
caused it to rupture, almost blinding Watkins. That problem resolved, Watkins took Frank Wild
, whom Mawson had hired to command a support base during the expedition, on another test flight the morning of the demonstration. In Watkins' account, which he addressed to Vickers' Aviation Department, he wrote: "[we were] about 200 ft. up. I got into a fierce tremor, and then into an air pocket, and was brought down about 100 ft., got straight, and dropped into another, almost a vacuum. That finished it. We hit the ground with an awful crash, both wings damaged, one cylinder broken, and the Nose bent up, the tail in half, etc."
Although the two men were only slightly injured, the plane was damaged beyond repair. Mawson decided to salvage the plane by converting it into a motorised sledge. He fitted the skis, and removed the wings and most of the sheathing to save weight. In his official account of the expedition, The Home of the Blizzard, Mawson wrote that the advantages of this "air-tractor sledge" were expected to be "speed, steering control, and comparative safety from crevasse
s owing to the great length of the runners". No longer needing a pilot, and believing him to be responsible for the crash, Mawson dismissed Watkins.
The air-tractor sledge was taken to Hobart, where the expedition ship SY Aurora was being loaded. It was secured on board in a crate lined with tin
, which weighed far more than the sledge itself, on top of the ship's forecastle
and two boat-skids. To fuel the sledge, along with the motor launch
and the wireless
equipment, the Aurora also carried 4000 gallons (18,184.4 l) of benzine
and 1300 gallons (5,909.9 l) of kerosene
. Fully loaded, the ship left Hobart on 2 December 1911.
to establish a wireless relay station and research base. The expedition's main base was established in Adélie Land
, at Cape Denison
in Commonwealth Bay
. While the Aurora was unloading, a violent whirlwind
lifted the 300 pounds (136.1 kg) lid off the air-tractor's crate, throwing it 50 yards (45.7 m). The main hut was erected immediately, but the strong winds meant that work on the air-tractor's hangar was delayed until March. When the winds abated, a 10 feet (3 m) by 35 feet (10.7 m) hangar was constructed next to the main hut, from empty packing cases.
Bickerton began work on the air-tractor sledge on 14 April 1912. His first job was to repair the sledge, which had been damaged in transit when a violent storm hit the Aurora. A giant wave had slammed into the crate containing the sledge, driving the fuselage 4 feet (1.2 m) through its side. With the repair completed, Bickerton began the serious work of converting the plane into a sledge. He constructed brakes from a pair of geological drills, and a steering system from the landing gear. Bickerton painted the engine and fuel tank black to absorb heat better and protect them from freezing. By June he had the engine running properly, and during a lull in the winds in early September he fitted the skis. Finally, he raised the fuselage 5 feet (1.5 m) off the ground to allow the propeller free movement.
On 27 October 1912, Mawson outlined the summer sledging program. Seven sledging parties would depart from Cape Denison, surveying the coast and interior of Adélie Land and neighbouring King George V Land. They were required to return to the base by 15 January, when the Aurora was due to depart; any later, it was feared, and she would be trapped by ice. Bickerton was to lead one of the parties, which would use the air-tractor to haul four sledges and explore the coast to the west of the hut. Most of the parties left in early November, but Bickerton's Western party delayed until December, in the hope of avoiding the ferocious winter winds. Work on the air-tractor sledge was delayed by the fierce winds, and the first trial took place on 15 November, between the main base and Aladdin's Cave—a depot which had been established on the plateau above Cape Denison. The air-tractor reached a speed of 20 miles per hour (8.9 m/s), covering the 5 miles (8 km), expedition member Charles Laseron
recorded, "in great style". Soon, the sledge began hauling cargo up the slope, laying depots for the summer sledging parties.
. The air-tractor made slow progress hauling its train of sledges, and about 10 miles (16.1 km) out from the base its engine began experiencing difficulty. Bickerton shut it down and the three set up camp. At 4 am the next morning the party set off again, but the engine continued to struggle; oil ejected from an idle cylinder and the cylinder's lack of compression led Bickerton to suspect broken piston ring
s to be the root of the problem. This would take only a matter of hours to fix. As he later recorded, "These thoughts were brought to a sudden close by the engine, without any warning, pulling up with such a jerk that the propeller was smashed. On moving the latter, something fell into the oil in the crank-case and fizzled, while the propeller could only be swung through an angle of about 30 [degrees]."
The party continued without the air-tractor, man-hauling the sledges to a point 158 miles (254.3 km) west of Cape Denison, and returned to base on 18 January 1913. Mawson's Far Eastern Party
failed to return, and six men, including Bickerton, remained for an extra winter. On 8 February, just hours after Aurora left Commonwealth Bay after waiting for three weeks, Mawson staggered alone into base, his colleagues Belgrave Edward Sutton Ninnis
and Xavier Mertz
dead. As Mawson was being nursed back to health, Bickerton dragged the air-tractor sledge back to base to diagnose the reason for its failure. He found that the freezing conditions had caused the engine oil
to congeal, jamming the pistons. He abandoned the sledge at Boat Harbour, next to the base. When Aurora returned to Cape Denison for the final time on 13 December 1913, only the engine and propeller were taken back to Australia.
in November 1916, requesting the company write off the bill as a donation. His company buoyed by armaments contracts, Dawson agreed. The next expedition to take a plane to the Antarctic was Shackleton's 1921–22 Quest Expedition, but the Avro Baby
remained grounded owing to missing parts. Not until 16 November 1928—when Hubert Wilkins
and Carl Ben Eielson flew for 20 minutes around Deception Island, just over a year before Admiral Richard Evelyn Byrd
's first flight over the South Pole—was a plane airborne in the Antarctic.
The frame of the air-tractor sledge remained on the ice at Boat Harbour where Bickerton had left it. The last expedition to Cape Denison to see the frame was in 1976; the next expedition, in 1981, could find no trace of it. The ice in that location does not move, and the implication is that the frame sank through the ice. It is therefore possible the frame is still there.
In 2007-8 a team from the Mawson's Huts Foundation
began to search for the remnants of the plane. Using photographs from 1913, 1931 and 1976 it was possible to derive transits between the frame and distant objects which located the frame to a small area of ice about 50 m from the hut. Comparison with a 1931 photograph by Frank Hurley confirmed this location.
The following summer (2008-9), the team extensively surveyed the area where they believed the air-tractor to be, using ground-penetrating radar
. A 3 metre deep trench was dug in a promising area, but nothing was found except fragments of seaweed indicating the overlying ice must have melted sometime in the past. Temperature records from the nearby Dumont d'Urville Station
showed that there had been extended periods (each of about six weeks) of above average temperatures in 1976 and 1981, suggesting the ice around the harbour could have melted. Dr Chris Henderson, the leader of the team, believes "the frame sank in situ to the rock surface, three metres below the present ice surface".
Next year (the 2009-10 season) further search was undertaken using differential GPS
, bathymetry
equipment, ice auger
s, a magnetometer and a metal detector (whose sensor was placed down the ice auger holes after drilling). The ice showed signs of having extensively melted in the past, was about 3 metres thick and covering smooth rock which extended Northwards to become the harbour bottom. Visual examination of the harbour bottom during the bathymetry survey did not reveal any fragments of the frame in the first 30 metres of the harbour.
The most significant findings from the ice survey were a positive reading from the metal detector, coupled with a significant echo from the Ground Penetrating Radar, both from the small area where the frame is assumed to have sunk.
Parts of the Air Tractor are already known to exist: The Australian Antarctic Division has one wheel from the frame, and its ice-rudder - both of which were found in the harbour. In January 2009 the remains of a seat from the air-tractor were found in rocks near the hut, about 200 metres (656.2 ft) from where the team believes the frame to be buried. On 1 January 2010, a day of unusually low tide, 4 small capping pieces from the end section of the tail were found by the edge of the harbour. The tail and a section of fuselage had been removed from the rest of the air-tractor before it was abandoned in 1913, therefore this discovery did not shed much light on the location of the rest of the frame, but it suggests that "the frame, or parts of it, can survive for nearly 100 years in this environment" Henderson.
The team returned to Cape Denison over the 2010–11 summer, but the crash of a French helicopter near Dumont d'Urville Station in October 2010 forced deployment of a much reduced team with no resources to continue the search.
The findings to date (2011) suggest that metal object(s) exist at a depth of 3 metres, on rock, in the location where the frame was last known to have been seen in 1976. This is likely to be the remains of Mawson's Air Tractor, but confirmation awaits a future opportunity.
Fixed-wing aircraft
A fixed-wing aircraft is an aircraft capable of flight using wings that generate lift due to the vehicle's forward airspeed. Fixed-wing aircraft are distinct from rotary-wing aircraft in which wings rotate about a fixed mast and ornithopters in which lift is generated by flapping wings.A powered...
taken on the 1911–14 Australasian Antarctic Expedition
Australasian Antarctic Expedition
The Australasian Antarctic Expedition was an Australasian scientific team that explored part of Antarctica between 1911 and 1914. It was led by the Australian geologist Douglas Mawson, who was knighted for his achievements in leading the expedition. In 1910 he began to plan an expedition to chart...
, the first plane to be taken to the Antarctic
Antarctic
The Antarctic is the region around the Earth's South Pole, opposite the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica and the ice shelves, waters and island territories in the Southern Ocean situated south of the Antarctic Convergence...
. Expedition leader Douglas Mawson
Douglas Mawson
Sir Douglas Mawson, OBE, FRS, FAA was an Australian geologist, Antarctic explorer and Academic. Along with Roald Amundsen, Robert Falcon Scott, and Ernest Shackleton, Mawson was a key expedition leader during the Heroic Age of Antarctic Exploration.-Early work:He was appointed geologist to an...
had planned to use the Vickers R.E.P. Type Monoplane
Vickers R.E.P. Type Monoplane
-References:* Andrews, C.F. and E.B. Morgan. Vickers Aircraft since 1908. London:Putnam, 1988. ISBN 0 85177 815 1.* ". Flight, 15 April 1911, p. 336.* . Flight, 29 July 1911, p. 663....
as a reconnaissance and search and rescue
Search and rescue
Search and rescue is the search for and provision of aid to people who are in distress or imminent danger.The general field of search and rescue includes many specialty sub-fields, mostly based upon terrain considerations...
tool, and to assist in publicity, but the aircraft crashed heavily during a test flight in Adelaide
Adelaide
Adelaide is the capital city of South Australia and the fifth-largest city in Australia. Adelaide has an estimated population of more than 1.2 million...
, Australia, only two months before Mawson's scheduled departure date. The plane was nevertheless sent south with the expedition, after having been stripped of its wings and metal sheathing from the fuselage. Engineer Frank Bickerton
Frank Bickerton
Frank Bickerton was an Antarctic explorer, and engineer, and a pioneer in the usage of aircraft and telegraphy. He also led a three man sledging team which discovered the first meteorite to be found in the Antarctic.-Life:...
spent most of the 1912 winter working to convert it to a sledge, fashioning brakes from a pair of geological drills and a steering system from the plane's landing gear
Landing Gear
Landing Gear is Devin the Dude's fifth studio album. It was released on October 7, 2008. It was his first studio album since signing with the label Razor & Tie. It features a high-profile guest appearance from Snoop Dogg. As of October 30, 2008, the album has sold 18,906 copies.-Track...
. It was first tested on 15 November 1912 and subsequently assisted in laying depots for the summer sledging parties, but its use during the expedition was minimal.
Towing a train of four sledges, the air-tractor accompanied a party led by Bickerton to explore the area to the west of the expedition's base at Cape Denison
Cape Denison
Cape Denison is a rocky point at the head of Commonwealth Bay in Antarctica. It was discovered in 1912 by the Australasian Antarctic Expedition under Douglas Mawson, who named it for Sir Hugh Denison of Sydney, a patron of the expedition...
. The freezing conditions resulted in the jamming of the engine's pistons after just 10 miles (16.1 km), and the air-tractor was left behind. Some time later it was dragged back to Cape Denison, and its frame was left on the ice when the expedition returned home in 1913. In 2008 a team from the Mawson's Huts Foundation
Mawson's Huts
"Mawson's Huts" are the collection of buildings located at Cape Denison, Commonwealth Bay, in the far eastern sector of the Australian Antarctic Territory, some 3000 km south of Hobart...
began searching for the remains of the air-tractor sledge; a seat was found in 2009, and fragments of the tail assembly a year later.
The Mawson's Huts Foundation has undertaken extensive investigation using sophisticated equipment in 2009 and 2010. Results indicate that the air tractor, or parts of it, is still buried under 3m of ice where it was abandoned at Cape Denison.
Background
Douglas MawsonDouglas Mawson
Sir Douglas Mawson, OBE, FRS, FAA was an Australian geologist, Antarctic explorer and Academic. Along with Roald Amundsen, Robert Falcon Scott, and Ernest Shackleton, Mawson was a key expedition leader during the Heroic Age of Antarctic Exploration.-Early work:He was appointed geologist to an...
had accompanied Ernest Shackleton
Ernest Shackleton
Sir Ernest Henry Shackleton, CVO, OBE was a notable explorer from County Kildare, Ireland, who was one of the principal figures of the period known as the Heroic Age of Antarctic Exploration...
's 1907–09 British Antarctic Expedition
Nimrod Expedition
The British Antarctic Expedition 1907–09, otherwise known as the Nimrod Expedition, was the first of three expeditions to the Antarctic led by Ernest Shackleton. Its main target, among a range of geographical and scientific objectives, was to be first to the South Pole...
. Along with Edgeworth David
Edgeworth David
Sir Tannatt William Edgeworth David KBE, DSO, FRS, was a Welsh Australian geologist and Antarctic explorer. A household name in his lifetime, David's most significant achievements were discovering the major Hunter Valley coalfield in New South Wales and leading the first expedition to reach the...
and Alistair Mackay
Alistair Mackay
Alistair Mackay was a Scottish doctor and polar explorer. He was one the trio of explorers, along with Douglas Mawson and Professor Edgeworth David, who became the first humans to reach the Magnetic South Pole.-Antarctica with Shackleton:...
, he had been part of a man-hauled
Manhauling
Manhauling, often expressed as man-hauling, means the pulling forward of sledges, trucks or other load-carrying vehicles by human power unaided by animals or machines...
sledging expedition, the first to reach the area of the South Magnetic Pole
South Magnetic Pole
The Earth's South Magnetic Pole is the wandering point on the Earth's surface where the geomagnetic field lines are directed vertically upwards...
. Upon his return from Antarctica, he recommenced to his post as geology lecturer at the University of Adelaide
University of Adelaide
The University of Adelaide is a public university located in Adelaide, South Australia. Established in 1874, it is the third oldest university in Australia...
. Despite an offer from Robert Falcon Scott
Robert Falcon Scott
Captain Robert Falcon Scott, CVO was a Royal Navy officer and explorer who led two expeditions to the Antarctic regions: the Discovery Expedition, 1901–04, and the ill-fated Terra Nova Expedition, 1910–13...
to join his Terra Nova Expedition
Terra Nova Expedition
The Terra Nova Expedition , officially the British Antarctic Expedition 1910, was led by Robert Falcon Scott with the objective of being the first to reach the geographical South Pole. Scott and four companions attained the pole on 17 January 1912, to find that a Norwegian team led by Roald...
to reach the Geographic South Pole
South Pole
The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...
, Mawson began planning his own Antarctic expedition. Mawson's plan, which led to the Australasian Antarctic Expedition
Australasian Antarctic Expedition
The Australasian Antarctic Expedition was an Australasian scientific team that explored part of Antarctica between 1911 and 1914. It was led by the Australian geologist Douglas Mawson, who was knighted for his achievements in leading the expedition. In 1910 he began to plan an expedition to chart...
, envisaged three bases on the Antarctic continent, collectively surveying much of the coast directly south of Australia. He approached Shackleton, who not only approved of his plan but was prepared to lead the expedition himself. Although Shackleton withdrew from the expedition in December 1910, he continued to assist Mawson with publicity and fund-raising.
Purchase
Mawson travelled to Britain in early 1911 to raise funds, hire crew, and purchase equipment. He considered taking a plane to the Antarctic, which could work as a reconnaissance tool, transport cargo, and assist with search and rescue. Crucially, as no plane had yet been taken to the continent, it could also be used to generate publicity. Unsure of the type of plane he should take, but considering a BlériotBlériot Aéronautique
Blériot Aéronautique was a French aircraft manufacturer founded by Louis Blériot. It also made a few cyclecars from 1921 to 1922.After Louis Blériot became famous for being the first to fly over the English Channel in 1909, he established an aircraft manufacturing company. This company really took...
, Mawson mentioned his plans to Scott's wife Kathleen Scott
Kathleen Scott
Kathleen Scott, Baroness Kennet, FRSBS was a British sculptor.-Early life:Born Edith Agnes Kathleen Bruce at Carlton in Lindrick, Bassetlaw, Nottinghamshire, she was the youngest of eleven children of Canon Lloyd Stuart Bruce and Jane Skene Kathleen Scott, Baroness Kennet, FRSBS (27 March...
, an aircraft enthusiast. She recommended he take a monoplane
Monoplane
A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...
, and conveyed his interest to Lieutenant Hugh Evelyn Watkins of the Essex Regiment
Essex Regiment
The Essex Regiment was an infantry regiment of the British Army that saw active service from 1881 to 1958. Members of the regiment were recruited from across Essex county. Its lineage is continued by the Royal Anglian Regiment.-Origins:...
. Watkins had connections with the ship and aircraft manufacturer Vickers Limited
Vickers Limited
Vickers Limited was a famous British engineering conglomerate that merged into Vickers-Armstrongs in 1927.-Early history:Vickers was formed in Sheffield as a steel foundry by the miller Edward Vickers and his father-in-law George Naylor in 1828. Naylor was a partner in the foundry Naylor &...
, which had recently entered into a licence agreement to build and sell aircraft in Britain designed by the Frenchman Robert Esnault-Pelterie
Robert Esnault-Pelterie
Robert Albert Charles Esnault-Pelterie was a pioneering French aircraft designer and spaceflight theorist. He was born in Paris, the son of a textile industrialist...
. In a letter to Mawson on 18 May, Kathleen wrote:
On Kathleen Scott's advice, Mawson purchased a Vickers R.E.P. Type Monoplane
Vickers R.E.P. Type Monoplane
-References:* Andrews, C.F. and E.B. Morgan. Vickers Aircraft since 1908. London:Putnam, 1988. ISBN 0 85177 815 1.* ". Flight, 15 April 1911, p. 336.* . Flight, 29 July 1911, p. 663....
, one of only eight built. It was fitted with a five-cylinder R.E.P. engine developing 60 hp, and had a maximum range of 300 miles (482.8 km) at a cruising speed of 48 knots (26.1 m/s). Its wingspan was 47 feet (14.3 m), and its length 36 feet (11 m). The pilot used a joystick
Joystick
A joystick is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. Joysticks, also known as 'control columns', are the principal control in the cockpit of many civilian and military aircraft, either as a center stick or...
for pitch and roll, with lateral control by wing warping
Wing warping
Wing warping was an early system for lateral control of a fixed-wing aircraft. The technique, used and patented by the Wright brothers, consisted of a system of pulleys and cables to twist the trailing edges of the wings in opposite directions...
. Mawson opted for a two-seater version, in a tandem arrangement, with a spare ski undercarriage. The total bill, dated 17 August 1911, came to £
£sd
£sd was the popular name for the pre-decimal currencies used in the Kingdom of England, later the United Kingdom, and ultimately in much of the British Empire...
955 4s 8d. Mawson hired Watkins to fly the plane, and Frank Bickerton
Frank Bickerton
Frank Bickerton was an Antarctic explorer, and engineer, and a pioneer in the usage of aircraft and telegraphy. He also led a three man sledging team which discovered the first meteorite to be found in the Antarctic.-Life:...
to accompany as engineer. After Vickers tested the aircraft at Dartford
Dartford
Dartford is the principal town in the borough of Dartford. It is situated in the northwest corner of Kent, England, east south-east of central London....
and Brooklands
Brooklands
Brooklands was a motor racing circuit and aerodrome built near Weybridge in Surrey, England. It opened in 1907, and was the world's first purpose-built motorsport venue, as well as one of Britain's first airfields...
, P&O
Peninsular and Oriental Steam Navigation Company
The Peninsular and Oriental Steam Navigation Company, which is usually known as P&O, is a British shipping and logistics company which dated from the early 19th century. Following its sale in March 2006 to Dubai Ports World for £3.9 billion, it became a subsidiary of DP World; however, the P&O...
shipped the plane to Adelaide aboard the steamship Macedonia, at half the usual rate of freight.
Crash
A series of public demonstrations were planned in Australia to assist in fund-raising, the first of which was scheduled for 5 October 1911 at the Cheltenham RacecourseCheltenham Park Racecourse
Cheltenham Park Racecourse was a horse racing track located in the suburb of Cheltenham in Adelaide, South Australia. It is situated north-west of the centre of the city and approximately five kilometres from Port Adelaide...
in Adelaide. During a test flight the day before, excessive pressure in the fuel tank
Fuel tank
A fuel tank is safe container for flammable fluids. Though any storage tank for fuel may be so called, the term is typically applied to part of an engine system in which the fuel is stored and propelled or released into an engine...
caused it to rupture, almost blinding Watkins. That problem resolved, Watkins took Frank Wild
Frank Wild
Commander John Robert Francis Wild CBE, RNVR, FRGS , known as Frank Wild, was an explorer...
, whom Mawson had hired to command a support base during the expedition, on another test flight the morning of the demonstration. In Watkins' account, which he addressed to Vickers' Aviation Department, he wrote: "[we were] about 200 ft. up. I got into a fierce tremor, and then into an air pocket, and was brought down about 100 ft., got straight, and dropped into another, almost a vacuum. That finished it. We hit the ground with an awful crash, both wings damaged, one cylinder broken, and the Nose bent up, the tail in half, etc."
Although the two men were only slightly injured, the plane was damaged beyond repair. Mawson decided to salvage the plane by converting it into a motorised sledge. He fitted the skis, and removed the wings and most of the sheathing to save weight. In his official account of the expedition, The Home of the Blizzard, Mawson wrote that the advantages of this "air-tractor sledge" were expected to be "speed, steering control, and comparative safety from crevasse
Crevasse
A crevasse is a deep crack in an ice sheet rhys glacier . Crevasses form as a result of the movement and resulting stress associated with the sheer stress generated when two semi-rigid pieces above a plastic substrate have different rates of movement...
s owing to the great length of the runners". No longer needing a pilot, and believing him to be responsible for the crash, Mawson dismissed Watkins.
The air-tractor sledge was taken to Hobart, where the expedition ship SY Aurora was being loaded. It was secured on board in a crate lined with tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
, which weighed far more than the sledge itself, on top of the ship's forecastle
Forecastle
Forecastle refers to the upper deck of a sailing ship forward of the foremast, or the forward part of a ship with the sailors' living quarters...
and two boat-skids. To fuel the sledge, along with the motor launch
Launch (boat)
A launch in contemporary usage refers to a large motorboat. The name originally referred to the largest boat carried by a warship. The etymology of the word is given as Portuguese lancha "barge", from Malay lancha, lancharan, "boat," from lanchar "velocity without effort," "action of gliding...
and the wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...
equipment, the Aurora also carried 4000 gallons (18,184.4 l) of benzine
Petroleum ether
Petroleum ether, also known as benzine, VM&P Naphtha, Petroleum Naphtha, Naphtha ASTM, Petroleum Spirits, X4 or Ligroin, is a group of various volatile, highly flammable, liquid hydrocarbon mixtures used chiefly as nonpolar solvents...
and 1300 gallons (5,909.9 l) of kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...
. Fully loaded, the ship left Hobart on 2 December 1911.
In Antarctica
The Aurora reached the Antarctic mainland on 8 January 1912, after a two-week stop on Macquarie IslandMacquarie Island
Macquarie Island lies in the southwest corner of the Pacific Ocean, about half-way between New Zealand and Antarctica, at 54°30S, 158°57E. Politically, it has formed part of the Australian state of Tasmania since 1900 and became a Tasmanian State Reserve in 1978. In 1997 it became a world heritage...
to establish a wireless relay station and research base. The expedition's main base was established in Adélie Land
Adélie Land
Adélie Land is the portion of the Antarctic coast between 136° E and 142° E , with a shore length of 350 km and with its hinterland extending as a sector about 2,600 km toward the South Pole. It is claimed by France as one of five districts of the French Southern and Antarctic Lands, although not...
, at Cape Denison
Cape Denison
Cape Denison is a rocky point at the head of Commonwealth Bay in Antarctica. It was discovered in 1912 by the Australasian Antarctic Expedition under Douglas Mawson, who named it for Sir Hugh Denison of Sydney, a patron of the expedition...
in Commonwealth Bay
Commonwealth Bay
Commonwealth Bay is an open bay about 48 km wide at the entrance between Point Alden and Cape Gray in Antarctica. It was discovered in 1912 by the Australasian Antarctic Expedition under Douglas Mawson, who established the main base of the expedition at Cape Denison at the head of the bay...
. While the Aurora was unloading, a violent whirlwind
Whirlwind (atmospheric phenomenon)
A whirlwind is a weather phenomenon in which a vortex of wind forms due to instabilities and turbulence created by heating and flow gradients. Whirlwinds occur all over the world and in any season....
lifted the 300 pounds (136.1 kg) lid off the air-tractor's crate, throwing it 50 yards (45.7 m). The main hut was erected immediately, but the strong winds meant that work on the air-tractor's hangar was delayed until March. When the winds abated, a 10 feet (3 m) by 35 feet (10.7 m) hangar was constructed next to the main hut, from empty packing cases.
Bickerton began work on the air-tractor sledge on 14 April 1912. His first job was to repair the sledge, which had been damaged in transit when a violent storm hit the Aurora. A giant wave had slammed into the crate containing the sledge, driving the fuselage 4 feet (1.2 m) through its side. With the repair completed, Bickerton began the serious work of converting the plane into a sledge. He constructed brakes from a pair of geological drills, and a steering system from the landing gear. Bickerton painted the engine and fuel tank black to absorb heat better and protect them from freezing. By June he had the engine running properly, and during a lull in the winds in early September he fitted the skis. Finally, he raised the fuselage 5 feet (1.5 m) off the ground to allow the propeller free movement.
On 27 October 1912, Mawson outlined the summer sledging program. Seven sledging parties would depart from Cape Denison, surveying the coast and interior of Adélie Land and neighbouring King George V Land. They were required to return to the base by 15 January, when the Aurora was due to depart; any later, it was feared, and she would be trapped by ice. Bickerton was to lead one of the parties, which would use the air-tractor to haul four sledges and explore the coast to the west of the hut. Most of the parties left in early November, but Bickerton's Western party delayed until December, in the hope of avoiding the ferocious winter winds. Work on the air-tractor sledge was delayed by the fierce winds, and the first trial took place on 15 November, between the main base and Aladdin's Cave—a depot which had been established on the plateau above Cape Denison. The air-tractor reached a speed of 20 miles per hour (8.9 m/s), covering the 5 miles (8 km), expedition member Charles Laseron
Charles Francis Laseron
Charles Francis Laseron , was an American-born Australian naturalist and malacologist.Charles Laseron was born on 6 December 1887 at Manitowoc, Wisconsin, United States of America, to English parents the Rev...
recorded, "in great style". Soon, the sledge began hauling cargo up the slope, laying depots for the summer sledging parties.
Broken
The Western party left Cape Denison on 3 December 1912. Accompanying Bickerton and the air-tractor were cartographer Alfred Hodgeman and surgeon Leslie WhetterLeslie Whetter
Leslie Hatton Whetter was a surgeon and Antarctic explorer from New Zealand. A graduate of the University of Otago, in 1911 he joined the Australasian Antarctic Expedition , led by Douglas Mawson...
. The air-tractor made slow progress hauling its train of sledges, and about 10 miles (16.1 km) out from the base its engine began experiencing difficulty. Bickerton shut it down and the three set up camp. At 4 am the next morning the party set off again, but the engine continued to struggle; oil ejected from an idle cylinder and the cylinder's lack of compression led Bickerton to suspect broken piston ring
Piston ring
A piston ring is a split ring that fits into a groove on the outer diameter of a piston in a reciprocating engine such as an internal combustion engine or steam engine.The three main functions of piston rings in reciprocating engines are:...
s to be the root of the problem. This would take only a matter of hours to fix. As he later recorded, "These thoughts were brought to a sudden close by the engine, without any warning, pulling up with such a jerk that the propeller was smashed. On moving the latter, something fell into the oil in the crank-case and fizzled, while the propeller could only be swung through an angle of about 30 [degrees]."
The party continued without the air-tractor, man-hauling the sledges to a point 158 miles (254.3 km) west of Cape Denison, and returned to base on 18 January 1913. Mawson's Far Eastern Party
Far Eastern Party
The Far Eastern Party was a sledging component of the 1911–14 Australasian Antarctic Expedition, which investigated the previously unexplored coastal regions of Antarctica west of Cape Adare. Led by expedition commander Douglas Mawson, the party aimed to explore the area far to the east of their...
failed to return, and six men, including Bickerton, remained for an extra winter. On 8 February, just hours after Aurora left Commonwealth Bay after waiting for three weeks, Mawson staggered alone into base, his colleagues Belgrave Edward Sutton Ninnis
Belgrave Edward Sutton Ninnis
Belgrave Edward Sutton Ninnis was a Lieutenant in the Royal Fusiliers and an Antarctic explorer who was a member of Sir Douglas Mawson's 1911 Australasian Antarctic Expedition.-Antarctica 1911-1912:...
and Xavier Mertz
Xavier Mertz
Xavier Mertz was a Swiss explorer, mountaineer and skier, from Basel. He took part in the Far Eastern Party, a 1912–13 component of the Australasian Antarctic Expedition, which claimed his life...
dead. As Mawson was being nursed back to health, Bickerton dragged the air-tractor sledge back to base to diagnose the reason for its failure. He found that the freezing conditions had caused the engine oil
Motor oil
Motor oil or engine oil is an oil used for lubrication of various internal combustion engines. The main function is to lubricate moving parts; it also cleans, inhibits corrosion, improves sealing, and cools the engine by carrying heat away from moving parts.Motor oils are derived from...
to congeal, jamming the pistons. He abandoned the sledge at Boat Harbour, next to the base. When Aurora returned to Cape Denison for the final time on 13 December 1913, only the engine and propeller were taken back to Australia.
Recovery efforts
The bill for the plane remained unpaid. In 1914 Vickers reminded Mawson, who had apparently forgotten the outstanding debt. Mawson wrote to Vickers director Sir Trevor DawsonTrevor Dawson
Commander Sir Arthur Trevor Dawson, 1st Baronet , known as Sir Trevor Dawson, was an English armaments manufacturer....
in November 1916, requesting the company write off the bill as a donation. His company buoyed by armaments contracts, Dawson agreed. The next expedition to take a plane to the Antarctic was Shackleton's 1921–22 Quest Expedition, but the Avro Baby
Avro Baby
-External links:* Contemporary technical description with photographs and drawings....
remained grounded owing to missing parts. Not until 16 November 1928—when Hubert Wilkins
Hubert Wilkins
Sir Hubert Wilkins MC & Bar was an Australian polar explorer, ornithologist, pilot, soldier, geographer and photographer.-Early life:...
and Carl Ben Eielson flew for 20 minutes around Deception Island, just over a year before Admiral Richard Evelyn Byrd
Richard Evelyn Byrd
Rear Admiral Richard Evelyn Byrd, Jr., USN was a naval officer who specialized in feats of exploration. He was a pioneering American aviator, polar explorer, and organizer of polar logistics...
's first flight over the South Pole—was a plane airborne in the Antarctic.
The frame of the air-tractor sledge remained on the ice at Boat Harbour where Bickerton had left it. The last expedition to Cape Denison to see the frame was in 1976; the next expedition, in 1981, could find no trace of it. The ice in that location does not move, and the implication is that the frame sank through the ice. It is therefore possible the frame is still there.
In 2007-8 a team from the Mawson's Huts Foundation
Mawson's Huts
"Mawson's Huts" are the collection of buildings located at Cape Denison, Commonwealth Bay, in the far eastern sector of the Australian Antarctic Territory, some 3000 km south of Hobart...
began to search for the remnants of the plane. Using photographs from 1913, 1931 and 1976 it was possible to derive transits between the frame and distant objects which located the frame to a small area of ice about 50 m from the hut. Comparison with a 1931 photograph by Frank Hurley confirmed this location.
The following summer (2008-9), the team extensively surveyed the area where they believed the air-tractor to be, using ground-penetrating radar
Ground-penetrating radar
Ground-penetrating radar is a geophysical method that uses radar pulses to image the subsurface. This nondestructive method uses electromagnetic radiation in the microwave band of the radio spectrum, and detects the reflected signals from subsurface structures...
. A 3 metre deep trench was dug in a promising area, but nothing was found except fragments of seaweed indicating the overlying ice must have melted sometime in the past. Temperature records from the nearby Dumont d'Urville Station
Dumont d'Urville Station
The Dumont d'Urville Station is a French scientific station located in Antarctica on Île des Pétrels, archipelago of Pointe Géologie in Adélie Land. It is named after explorer Jules Dumont d'Urville...
showed that there had been extended periods (each of about six weeks) of above average temperatures in 1976 and 1981, suggesting the ice around the harbour could have melted. Dr Chris Henderson, the leader of the team, believes "the frame sank in situ to the rock surface, three metres below the present ice surface".
Next year (the 2009-10 season) further search was undertaken using differential GPS
Differential GPS
Differential Global Positioning System is an enhancement to Global Positioning System that provides improved location accuracy, from the 15-meter nominal GPS accuracy to about 10 cm in case of the best implementations....
, bathymetry
Bathymetry
Bathymetry is the study of underwater depth of lake or ocean floors. In other words, bathymetry is the underwater equivalent to hypsometry. The name comes from Greek βαθύς , "deep", and μέτρον , "measure"...
equipment, ice auger
Auger
An auger is a drilling device, or drill bit, that usually includes a rotating helical screw blade called a "flighting" to act as a screw conveyor to remove the drilled out material...
s, a magnetometer and a metal detector (whose sensor was placed down the ice auger holes after drilling). The ice showed signs of having extensively melted in the past, was about 3 metres thick and covering smooth rock which extended Northwards to become the harbour bottom. Visual examination of the harbour bottom during the bathymetry survey did not reveal any fragments of the frame in the first 30 metres of the harbour.
The most significant findings from the ice survey were a positive reading from the metal detector, coupled with a significant echo from the Ground Penetrating Radar, both from the small area where the frame is assumed to have sunk.
Parts of the Air Tractor are already known to exist: The Australian Antarctic Division has one wheel from the frame, and its ice-rudder - both of which were found in the harbour. In January 2009 the remains of a seat from the air-tractor were found in rocks near the hut, about 200 metres (656.2 ft) from where the team believes the frame to be buried. On 1 January 2010, a day of unusually low tide, 4 small capping pieces from the end section of the tail were found by the edge of the harbour. The tail and a section of fuselage had been removed from the rest of the air-tractor before it was abandoned in 1913, therefore this discovery did not shed much light on the location of the rest of the frame, but it suggests that "the frame, or parts of it, can survive for nearly 100 years in this environment" Henderson.
The team returned to Cape Denison over the 2010–11 summer, but the crash of a French helicopter near Dumont d'Urville Station in October 2010 forced deployment of a much reduced team with no resources to continue the search.
The findings to date (2011) suggest that metal object(s) exist at a depth of 3 metres, on rock, in the location where the frame was last known to have been seen in 1976. This is likely to be the remains of Mawson's Air Tractor, but confirmation awaits a future opportunity.
See also
- Heroic Age of Antarctic ExplorationHeroic Age of Antarctic ExplorationThe Heroic Age of Antarctic Exploration defines an era which extended from the end of the 19th century to the early 1920s. During this 25-year period the Antarctic continent became the focus of an international effort which resulted in intensive scientific and geographical exploration, sixteen...
- Aerosani, Russian purpose-built propeller-driven sledges
- HydrocopterHydrocopterA hydrocopter is an amphibious aircraft-propelled catamaran. The vehicle has a boat-like hull, small wheels and pontoon skids . An aircraft engine with aircraft propeller and air rudder pushes the hydrocopter across water, ice, snow and land.It is very useful in arctic coastal regions during...
- Screw-propelled vehicle