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Accidents and opportunities: a history of the radio echo-sounding of Antarctica, 1958–79

Published online by Cambridge University Press:  09 June 2008

SIMONE TURCHETTI*
Affiliation:
Division of History and Philosophy of Science (HPS), University of Leeds, UK
KATRINA DEAN
Affiliation:
British Library
SIMON NAYLOR
Affiliation:
Department of Geography, University of Exeter, UK
MARTIN SIEGERT
Affiliation:
School of GeoSciences, University of Edinburgh, Scotland.
*
(corresponding author: [email protected])

Abstract

This paper explores the history of radio echo-sounding (RES), a technique of glaciological surveying that from the late 1960s has been used to examine Antarctica's sub-glacial morphology. Although the origins of RES can be traced back to two accidental findings, its development relied upon the establishment of new geopolitical conditions, which in the 1960s typified Antarctica as a continent devoted to scientific exploration. These conditions extended the influence of prominent glaciologists promoting RES and helped them gather sufficient support to test its efficiency. The organization and implementation of a large-scale research programme of RES in Antarctica followed these developments. The paper also examines the deployment of RES in Antarctic explorations, showing that its completion depended on the availability of technological systems of which RES was an integral part.

Type
Research Article
Copyright
Copyright © 2008 British Society for the History of Science

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References

1 D. Drewry (ed.), Antarctica's Glaciological and Geophysical Folio, Cambridge, 1983.

2 See R. Fifield, International Research in the Antarctic, Oxford, 1987, 36–7; G. E. Fogg, A History of Antarctic Science, Cambridge, 1992.

3 We use the term ‘big science’ with reference to the use of long-range aircraft as a polar research ‘laboratory’ to cover the entirety of the Antarctic continent. We also refer to the setting up of large teams of administrators, pilots, technicians and scientists to fulfil the research task assigned. This does not necessarily imply that our case study is comparable budgetarily with other well-known examples of big science such as high-energy physics. On big science see P. Galison and B. Hevly (eds.), Big Science: The Growth of Large-Scale Research, Stanford, 1992; D. de Solla Price, Little Science, Big Science, New York, 1963.

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11 New devices such as modulators (klystrons and cavity magnetrons) allowed the production of pulses of high frequency (HF) or very high frequency (VHF) that also augmented the power of radar transmitters and receivers. See R. Buderi, The Invention that Changed the World: The Story of Radar from War to Peace, New York, 1996.

12 The acronym SCR is of unclear origins: a model produced by the US Army Signal Research Corps or just ‘Set, Complete, Radio’.

13 On Operation Highjump see L. A. Rose, Assault on Eternity: Richard E. Byrd and the Exploration of Antarctica, 1946–1947, Annapolis, 1980. See also R. Doel, op. cit. (7).

14 Only from 1970 did this rate drop significantly. J. C. Behrendt, The Ninth Circle: A Memoir of Life and Death in Antarctica, 1960–1962, Albuquerque, 2005, 8.

15 Behrendt, op. cit. (14), 41. Quote taken from G. A. Doumani, The Frigid Mistress: Life and Exploration in Antarctica, Baltimore, 1999.

16 Waite and Schmidt, op. cit. (10), 1520.

17 Waite and Schmidt, op. cit. (10), 1520. E. K. Gannett, ‘Radar Altimeters fooled by polar ice and snow’, News Release from IRE, 20 March 1961.

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22 Special Committee on publications, 26 November 1957, in ‘IGY British National Committee–Minutes and Papers’, IGY/4/1, Jodrell Bank Archive, John Rylands Library, University of Manchester (hereafter JBA).

23 Evans's achievements were reported in the British magazine Discovery, as he managed to produce remarkable pictures of the aurora australis. A. Croome, ‘The IGY month by month’, Discovery, May 1957, 210.

24 Evans cabled Lovell that it was vital to the success of their programme that the interference problem be solved. Stanley Evans to Bernard Lovell, 25 June 1956, cable R.S.86, in ‘IGY Minutes and Reports, Antarctic Subcomittee’, IGY 3/1, JBA.

25 Evans, S. and Thomas, G. M., ‘The southern auroral zone in Geomagnetic Longitude Sector 20E’, Journal of Geophysical Research (1959), 64, 1381–8CrossRefGoogle Scholar; Evans, S., ‘Horizontal movements of visual auroral features’, Journal of Atmospheric and Terrestrial Physics (1959), 16, 190–2CrossRefGoogle Scholar; idem, ‘Systematic movements of aurorae at Halley Bay’, Proceedings of the Royal Society A (1960), 256, 234–40.

26 Drewry, D., ‘Gordon de Quetteville Robin: A Remembrance’, Polar Record (2005), 41, 177–81CrossRefGoogle Scholar.

27 Piggott, W. R. and Barclay, L. W., ‘The reflection of radio waves from an iceshelf’, Journal of Atmospheric and Terrestrial Research (1961), 20, 298–9CrossRefGoogle Scholar. ‘This was attributed to the effect of interference between the waves radiated directly upwards from the aerials to that which is radiated downwards through the ice and reflected from the bottom.’ Evans, op. cit. (19), 407.

28 Evans, S., ‘Polar ionospheric spread echoes and the radio frequency properties of ice shelves’, Journal of Geophysical Research (1961), 66, 4137–41CrossRefGoogle Scholar, 4141.

29 Evans, op. cit. (28), 4138. See also Mulkay, M., ‘Conceptual displacement and migration in science: a prefatory paper’, Science Studies (1974), 4, 205–34CrossRefGoogle Scholar, 218. Evans was awarded a grant from the Paul Instrument Fund (PIF, established under the will of R. W. Paul, inventor of the ‘unipivot galvanometer’) and received £2,736 in May 1962, £1,555 in October 1962 and £1,000 in September 1973 for the development of an echo-sounder for ice-thickness measurements. ‘PIF Grants’, MS 840/1, Royal Society Archives, London. Michael (‘Mike’) E. R. Walford assisted Evans in the construction of the instrument.

30 Evans, op. cit. (19), 406.

31 Within SCAR, eight working groups were also set up: Biology, Geodesy and Cartography, Geology, Glaciology, Human Biology and Medicine, Logistics, Solid Earth Geophysics, Upper Atmosphere Physics. See Fifield, op. cit. (2), 5.

32 The twelve signatory members, ‘Recognizing that it is in the interest of all mankind that Antarctica shall continue for ever to be used exclusively for peaceful purposes … and Acknowledging the substantial contributions to scientific knowledge resulting from international cooperation in scientific investigation … Agreed that Antarctica shall be used for peaceful purposes only … (Article 1) and that Freedom of scientific investigation in Antarctica and cooperation toward that end, as applied during the International Geophysical Year, shall continue, subject to the provisions of the present Treaty (Article 2).’ The Antarctic Treaty, 1959. (The whole treaty is available at http://www.antarctica.ac.uk/About_Antarctica/Treaty/treaty.html.)

33 F. Korsmo, ‘Science in the Cold War: the legacy of the IGY’, NSF Special Scientific Report 98–07, 7 April 1998. See also Korsmo, F. and Sfraga, M. P., ‘From interwar to Cold War: selling field science in the United States, 1920s through 1950s’, Earth Sciences History (2003), 22, 55–78CrossRefGoogle Scholar.

34 A. Elzinga, ‘The interplay of research and politics: the case of Antarctica’, in Society and the Environment: A Swedish Research Perspective (ed. U. Sverdin and B. H. Anisansson), Dordrecht, 1992, 257–83. See also K. Dodds, Geopolitics in Antarctica: Views from the Southern Oceanic Rim, New York, 1997.

35 ‘SCAR Bulletin. 4th meeting, Cambridge, 29.8/2.9.1960’, Polar Record (1960), 10, 416.

36 H. K. Bourne (UK scientific observer in Antarctica), ‘Some Notes on Polar Research’, undated (but early 1960s) in AD3/1/AS/131/1 (2) Part 2, BAS Archives, Cambridge (hereafter BAS). On the origins of seismic reflection see C. C. Bates, T. F. Gaskell and R. B. Rice, Geophysics in the Affairs of Man, Oxford, 1982.

37 A. Waite, ‘The International Cooperative Experiment on Glacial Sounding, sponsored by USAEL and USACRREL, Greenland 1963 and 1964’, paper presented at the Glacier Mapping Symposium, Canadian National Research Council, Ottawa, 15 September 1965.

38 The headquarters of the US Army Electronics Research and Development Laboratory were based in Thule, a US Air Force base and a vital and heavily militarized centre in North America's first line of defence in the Arctic. C. Swithinbank, Forty Years on Ice: A Lifetime of Exploration and Research in the Polar Regions, Sussex, 1998, 79.

39 R. Doel and A. A. Needell, ‘Science, scientists and the CIA: balancing international ideals, national needs and professional opportunities’, in Eternal Vigilance? 50 Years of the CIA (ed. R. Jeffreys-Jones and C. Andrews), London, 1997, 59–81.

40 Waite claimed that the radar altimeters and radio-echo equipment ‘worked successfully’. Evans, however, claimed that the apparatus had worked efficiently but was not powerful enough. Evans, S., ‘International cooperative field experiment in glacier sounding’, Polar Record (1963), 11, 725–6Google Scholar. According to an anonymous reviewer, ‘Waite failed to obtain good results with his high-frequency altimeter, he obtained virtually continuous echoes’. Anon., ‘RES’, Ice (1962), 16, 1012Google Scholar. Finally, Bentley claimed that the ‘30 MHz system did better than Bud's [Waite] 440 MHz system, because I remember there was a frequency factor … 440 was, it was just too high frequency … Stan's system failed before we got very deep, but still it was, it proved that the system had worked, and then it was just a matter of continuing development.’ Interview with Professor Emeritus C. Bentley at the University of Wisconsin-Madison, USA, 6 October 2005.

41 Walford, M. E. R., ‘RES through an ice shelf’, Nature (1964), 204, 317–19CrossRefGoogle Scholar.

42 Evans wrote, ‘these operations represented the biggest leap forward in technique and analysis so far’. They especially helped to consider the greater accuracy provided by RES systems with respect to seismic sounding. Evans, S., ‘Progress Report on RES’, Polar Record (1967), 13, 413–20CrossRefGoogle Scholar, 414. It is worth noting that the use of visual feedback made RES similar to marine echo-sounding, even though the latter is based on acoustic – rather than electromagnetic – means of remote sensing.

43 Swithinbank, op. cit. (38), 36.

44 In October 1965 one of Evans's assistants, J. T. Bailey, died in a crevasse whilst surveying a large unknown sector from Halley Bay to the Weddell Sea. He and two attendants, D. Wild and J. Wilson, lost their lives 250 miles from the base. His mission logbook is at the SPRI. See ‘Bailey's logbooks, 1965’, T. H. Manning Archive, SPRI, University of Cambridge (hereafter THMA).

45 Detailed description of the plan is in Appendix I – Airborne Laboratory, 44–6 of ‘Plans for U.S. Science Activities in Antarctica, 1968–1972 (Five Year projection)’, 1 June 1968, in ‘Budget’, Box 1, NSF 307/32, US National Archives and Record Administration, Washington, DC (hereafter NARA).

46 In 1965 the OAP codirector, T. O. Jones, wrote to Crary about Bentley's programme, stating that ‘I am assuming that we can avoid a traverse in the 1966–67 summer. Bentley has talked about a small Pole to Ellsworth Mountain traverse, but because of the possibilities of an air-borne radio-sounder, I would rather not operate the traverse at least for a number of years’. T. O. Jones to A. P. Crary, 30 August 1965, in ‘Budget’, Box 1, NSF 307/32, NARA.

47 As the note ‘Soviet Antartic maps’, Polar Records (1961), 10, 528, shows, mapping activities of Soviet parties had been monitored since the late 1950s. Evans had been especially interested in Russian advancement in radio-glaciology and visited Leningrad in 1966. Evans, op. cit. (19), 413–20; idem, ‘Fale radiowe w badaniach glacjologicznych’, Prezglad. Geofizyczny (1967), 12, 383–400. On Soviet maps see V. G. Bakaev, Atlas of Antarctica, Moscow, 1966.

48 A sum of $30,000 had been already allocated for this plan. T. O. Jones to A. P. Crary, 30 August 1965, and ‘Preliminary forecast of 1966–7 U.S. Antarctic Research Program Activities (Prepared for the Naval Support Force, Antarctica Conference)’, 9 August 1965, in ‘Budget’, Box 1, NSF 307/32, NARA.

49 Jiracek reported that ‘Evans puts a lot of emphasis on the need for a video amplifier prior to the intensity modulation. I'm sure his emphasis is well founded but I'm not clear as to what his reasons are, therefore not convinced of its importance … Also I feel that recording is tedious, of questionable accuracy, and very time consuming’. G. R. Jiracek, ‘RF equipment considerations’, 17 August 1964, in ‘Experiments in radio sounding of Polar ice thickness’, Paper 86–5355, copy in C. Bentley's Papers at the Byrd Polar Research Center, The Ohio State University Archives.

50 For a technical analysis of the differences between the RES systems see Plewes, L. A. and Hubbard, B., ‘A review of the use of radio-echo sounding in glaciology’, Progress in Physical Geography (2001), 25, 3, 203–36CrossRefGoogle Scholar, 209.

51 It seems to us the real issue was not one of technological superiority, but rather one of traditions or ‘material cultures’ in instrument- and experiment-making. One may even draw on P. Galison's notions of ‘image’ (Evans) and ‘logic’ (Waite, Jiracek) to explain it. P. Galison, Image and Logic: A Material Culture of Microphysics, Chicago, 1997.

52 A. Crary to G. Robin, 12 January 1967, in ‘Glaciology ice sounding by radio techniques (Dr. Evans), 1962–1972’, AD3/1/AS/139 (3), BAS. Drewry, op. cit. (26), 179, seems to suggest that this followed Robin's initiative.

53 See ‘Foreword’, Polar Record (1965), 12, 681. The operating budget of the foundation for supporting research worldwide was in the range of twenty million dollars. On the funding activities of the Ford Foundation see Krige, op. cit. (7), 172–3.

54 On returning to Britain in February 1967 Swithinbank had shown Crary the preliminary results of his Antarctica RES flights, which had excited the latter. Swithinbank, op. cit. (38), 40.

55 NERC continued funding the SPRI in relation to the joint initiative for the following thirteen years.

56 The first mission in 1967–8 also included the BAS.

57 Smith to Robin, 25 March 1970, in ‘UK 1970’, Box 31, NSF 307/64, NARA.

58 Smith argued that aside from political concerns, there were also financial concerns for the new strategy of funding, as the new US science policy tried to cut down on the number of organizations requiring financial assistance to keep them running. Smith to Robin, 7 May 1970, in ‘UK 1970’, Box 31, NSF 307/64, NARA.

59 In interview Drewry agreed that it was a sort of ‘military campaign’: ‘The optimal situation was to have two flight crews in operation in order to have maximum flying time. When one crew came in another would be ready to go out. They would have the program planned two or three flights ahead. But they couldn't go beyond that due to changing conditions and requirements. They would try to get the flight crews to compete with each other in order to cover the most territory. They explained to the Navy personnel what they were trying to do and tried to recruit them to the cause of polar exploration, get them involved so they would get the best outcome for the flight campaign. All sorts of information had to be coordinated in the planning room.’ Interview with Professor David Drewry at the University of Hull, UK, 6 April 2004.

60 Although the RES system would work efficiently regardless of these conditions, the navigation apparatus of the aircraft was more likely to be affected. Evans, S., Drewry, D. and Robin, G., ‘RES in Antarctica, 1971–1972’, Polar Record (1972), 16, 207–12CrossRefGoogle Scholar.

61 This coordination was so good that it has preserved the usability of the data to the present. The fact that so much data was recorded in a robust format that withstood the subsequent digital revolution in scientific technologies means that it can still be used for glaciological purposes (even though the navigational errors are far greater than would now occur). Furthermore, with modern digital processing techniques, the analogue data can be processed and scrutinized as if they were new data. Thus the data have acquired a usefulness that was almost certainly not originally envisaged.

62 Evans, S. and Smith, B. M. E., ‘A radio echo equipment for depth sounding in polar ice sheets’, Journal of Physics E: Scientific Instruments (1969), 2, 131–6CrossRefGoogle Scholar. The Mark III model was never used during the SPRI–NSF missions because it was conceived for small-scale work, possibly of commercial type, on temperate glaciers.

63 See, amongst others, V. V. Bogorodskij, G. V. Trepov and B. A. Federov, On measuring dielectric properties of glaciers in the field in Proceedings of the International Meeting on Radioglaciology (ed. P. Gudmansen), Technical University of Denmark, Lyngby (Denmark), May 1970, 20–31; P. Gudmansen, ‘Notes on radar sounding of the Greenland peninsula’, in ibid., 124–33; and S. Evans, ‘Review of the radio echo system performance in Gudmansen, P. E.’, in ibid., 100–2. For a technical analysis of the differences between the various RES systems see Plewes and Hubbard, op. cit. (50), 210–11.

64 ‘Proposed SPRI/NSF RES Operations in Antarctica, Spring 1973’, ‘SPRI-Ice thickness’, Box 30, NSF 307/64, NARA.

65 R. Zwally's note, 5 June 1973, in ‘SPRI-Ice thickness’, Box 30, NSF 307/64, NARA.

66 Thanks to one of the anonymous referees for highlighting this issue to us.

67 Marshall M. Lee, Winning with People: The First 40 Years of Tektronix, Beaverton, 1986.

68 Monitoring considerations dictated that Evans adopt a pulse radar system rather than a frequency-modulated one: ‘A pulse radar system was chosen mainly for this reason, because the monitor output is immediately interpretable, whereas a frequency-modulated system would require a bulky multi-channel analyzer to present complicated output information in a similar form’. Evans and Smith, op. cit. (62), 135.

69 Evans's previous work in ionosphere research also played a role in this realization: ‘We then realized that these ideas which had been developed generally in radar, and in my particular case the meteors, and a lot of ionospheric analysis – they could just be lifted straight in. It was very easy … We have drawn a terrific lot of analogies, a lot of results from ionospheric work; fading patterns, movement, reflections from rough surfaces, propagation through irregular media, it is all very closely related to the ionospheric thing.’ Mulkay, op. cit. (29), 219.

70 This is shown in the logbooks of the Greenland experiment. For example: 24 June 1964, ‘bottom echoes obscured by scatter. Watch abandoned’; ‘echo begins to merge … no echo observed’. 28 June 1964, ‘Complicated shallow region, very shallow echoes’. Similar remarks continued to appear in late logbooks and during all SPRI–NSF missions. See Greenland Logbooks, 1964, THMA.

71 The operator would record on logbook ‘OS-open shutter’; ‘CS-close shutter’. Logbooks of earlier operations show records of signal attenuation (expressed in dB) as well as pulse rate (in μs). Interestingly, the pulse rate would also be expressed in div. (divisions per second), showing again the importance of visual feedback from the oscilloscope. Division is each square of the lattice's graticule that appears on the oscilloscope. See Greenland experiments logbooks, 1964, and Ellesmere Island logbooks, 1966, THMA.

72 This also ‘gave an invaluable boost to the enthusiasm of both aircrew and scientists, as well as providing data of the highest quality’. Drewry, D. J. and Meldrum, D. T., ‘Antarctic airborne radio echo sounding, 1977–1978’, Polar Record (1978), 19, 267–73CrossRefGoogle Scholar. On the echo-strength apparatus see Neal, C. S., ‘Radio-echo power profiling’, Journal of Glaciology (1976), 17, 527–30CrossRefGoogle Scholar.

73 Anon., ‘Radio echo exploration of the Antarctic ice sheet’, Polar Record (1967), 14, 211–13Google Scholar.

74 Description of the new C130 for Antarctic exploration is given in ‘Use of jet-prop aircraft at US Antarctic stations, 1960’, Polar Record (1960), 10, 298. On performance during missions see Drewry and Meldrum, op. cit. (72), 268.

75 In dead reckoning navigation the aircraft position is estimated considering course (direction of travel), speed and distance of the aircraft at a certain moment in time during travel.

76 Robin, G., Drewry, D. and Meldrum, D., ‘International studies of ice sheet and bedrock’, Philosophical Transactions of the Royal Society of London (1977), 279, 185–96CrossRefGoogle Scholar.

77 Drewry, D., ‘RES map of Antarctica’, Polar Record (1975), 17, 359–60CrossRefGoogle Scholar. This was obtained through the use of three cameras placed on the same frame, but at different angles. The SPRI archive still has cameras that were very probably used during these missions, one a large Zeiss Ikon camera made in Germany, the other the K20 model produced by the Fomer Graflex Corp for the US Air Force, normally used in reconnaissance operations. On the importance of photogrammetry see Cloud, op. cit. (8), 263.

78 Litton was a start-up company that ‘played a major part in the development … and became AC Delco's original main competitor in the civil air market’. D. Mackenzie, Inventing Accuracy: A Historical Sociology of Nuclear Missile Guidance, Cambridge, MA, 1990, 174.

79 Drewry, op. cit. (77).

80 On land carriers such as the Polecat, an odometer was sufficient for linking position and vertical measurements. See J. T. Bailey logbooks, 1965, THMA.

81 Produced by the French Société de fabrication d'instruments de mesure (SFIM, now SAGEM).

82 The correlation with the aircraft navigation system was provided by an SFIM using a 60 mm photographic paper, which carried altitude, temperature, heading and terrain-clearance traces. Anon., op. cit. (73), 211.

83 Ellesmere Island logbooks, 1966, THMA.

84 Still available for consultation are seventeen radio echo logs and thirteen glaciologists logs for the second mission (1969–70); six radio echo logs and ten glaciologists logs for the third mission; twenty-five glaciologists logs, three TUD panel logs; eight SPRI panel logs for the fourth mission, 1974–5, THMA.

85 Petrie was instrumental in suggesting the use of terminated dipoles rather than half-wave dipoles. On antenna drag see Laurence Burke, ‘Radar aboard aircraft’, in Encyclopedia of 20th-Century Technology (ed. C. A. Hempstead and W. A. Worthington, Jr), New York and London, 2004, 621–3, 621.

86 Anon., op. cit. (40), 212.

87 Evans, S. and Smith, B., ‘Radio echo exploration of the Antarctic ice sheet, 1969–1970’, Polar Record (1970), 15, 336–8CrossRefGoogle Scholar.

88 Evans, Drewry and Robin, op. cit. (60).

89 See Drewry and Meldrum, op. cit. (72).

90 On data integration see K. Dean, S. Naylor, S. Turchetti and M. Siegert, ‘Data in Antarctic science and politics’, forthcoming in Social Studies of Science.

91 See Naylor, S., Siegert, M., Dean, K. and Turchetti, S., ‘Science, geopolitics and the governance of Antarctica’, Nature Geosciences (2008), 1, 143–5CrossRefGoogle Scholar.

92 Korsmo, op. cit. (33).

93 A. Enzinga, ‘Geopolitics, science and internationalism during and after the IGY’, 2nd Workshop of the SCAR Action Group on the History of Antarctic Research, Santiago, 21–2 September 2006.

94 Recent airborne RES projects in Antarctica have been discussed by F. Ferraccioli and J. W. Holt in the context of the ‘Post-international polar year: geophysical exploration of Antarctica’ session during the American Geophysical Union fall meeting, 11–15 December 2006.

95 Cloud and Clarke, op. cit. (8), 261–82. See also Cloud, J., ‘Imaging the world in a barrel: CORONA and the clandestine convergence of the earth sciences’, Social Studies of Science (2001), 31, 231–51CrossRefGoogle Scholar.

96 Interview with Dr C. Swithinbank in Cambridge, UK, 2 June 2004. The plausibility of such potential developments of RES was confirmed by the fact that Evans later went on to develop soil-sounding techniques for application to archaeological research.

97 Dean et al., op. cit. (90), 19.

98 Dean et al., op. cit. (90), 15–17.

99 ‘Exploration is no longer the prime attraction in Antarctic research. Modern satellite photography provides a wealth of geographical and physical details on an almost routine basis. The contemporary thrust of Antarctic research is toward examination of significant phenomena for a more comprehensive understanding of the polar environment in context with global natural and physical problems.’ ‘NSF Science Operation Plan, 1977–1982’, in ‘Long Range Plans’, Box 1, NSF 307/93, NARA.

100 Amongst the problems experienced during the sixth mission there was a cracked tyre, damage to the port of one external fuel tank that reduced fuel capacity, and problems with one generator that affected the performance and functioning of electronic apparatus deployed on the aircraft. See Drewry, D. J., Meldrum, D. T. and Jankowski, E., ‘Radio echo and magnetic sounding of the Antarctic ice scheet, 1978–1979’, Polar Record (1980), 20, 4357CrossRefGoogle Scholar.

101 In 1977–8 only 141 hours of 450 planned were flown.