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Victoria University Antarctic Research Expedition Science and Logistics Reports 1977-78: VUWAE 22

FIELD NOTES

page 11

FIELD NOTES

A. Transport

(a) Toboggans Event 12

Using two OMC two-stroke toboggans (NZARP No. 23 and 25) Event 12 suffered only minor mechanical failures. Toboggan 23 was used for all but 3 weeks of the 3 month field season on the Taylor Glacier. Toboggan 25 was used for the initial survey trip from the snout to Depot Nunatak, where it was handed over to Event 13 for their travel downglacier. Full accounts of mechanical repairs and problems are listed below:

NZARP 23 OMC

Scott Base
23-31 Oct Minor repairs and familiarisation of toboggans. Repaired pull-start cord and broken drive-chain during field testing of equipment.
Taylor Glacier
4 Nov Locking nut on end of flywheel and primary clutch sheave coming loose.
10 Locking nut still coming loose. Scott Base sending out new one on next resupply
28 Left hand idle spring replaced
29 General toboggan maintenance and tuning
1 Dec Replaced shoulder for leaf spring left ski and one right hand idle spring.
5 Left hand idle spring replaced. Changed primary sheave locking nut and flange. Took slack out of drive-chain. Clean and check plug gaps.
16 Toboggan running rough, seems like fuel starving.
8 Jan Replaced fuel pump, still rough.
12 Replaced pull-start recoil spring. Still poor carburettion, but no solution.
17 Primary sheave clutch spring broken, temporary repairs.
18 Base mechanic did check of toboggan. Points, advance and retard, fuel mixture all checked. Replaced primary clutch assembly. Still not running well underload and when warmed up.
21 Both rear swinging arms and bearings replaced.
page 12

NZARP 25 OMC Event 12

Scott Base
23-31 Oct Minor repairs and familiarisation. Idling problems.
Taylor Glacier
3 Nov Adjustment to mixture, due to lean running.
6 Carburettion problems. No ratchet grip on pull-start, reset and tighten mounting.
10 Changed spark plugs, just flooding.
20 Still idling problems.
21 Handed toboggan over to Event 13.

Estimated mileage for OMC 23 600-640 kilometers, during which time the major problem was poor carburettion. All other repairs were minor, except for the two rear swing arms. The failure of this back suspension resulted from the wear and consequent loosening of a locking sleeve on the left hand side of the rear axle. This allowed the axle to twist and pull out of the left hand bearing and swinging arm mounting. The right hand swinging arm snapped away from the toboggan body thus allowing the whole rear axle assembly to break loose, bringing the toboggan to an immediate stop.

(a) Toboggans Event 13

Three OMC 2 stroke toboggans (NZARP Nos. 22, 24 and 25) were used. Number 25 was used on the Taylor Glacier, the other two on the coastal trip to Cape Royds. Only minor problems were encountered, which were not sufficient to cause any delays. Pull start chords were replaced after breaking on all three machines. Also none of the machines idled satisfactorily. Starting difficulties were experienced particularly with Nos. 22 and 25 until the temperaments of the individual machines had been determined. A new throttle cable was fitted to No. 22 after breaking at Cape Evans. No. 25 proved particularly difficult to start on a number of occasions, the problem being a faulty primer pump which necessitated detaching the primer hose and sealing with a finger until sufficient suction to draw fuel was established. This machine was also used without neutral lockout after failure of a lock washer and subsequent clutch failure while Event 12 had the machine. The non-availability of spare clutch parts when we went into the field meant this fault could not be repaired.

Fortunately no track and suspension problems were experienced, no springs were broken. This was probably due to good advice we received on loading the sledges and not the toboggans. In general only the driver travelled on the toboggan. Oh smooth glacier ice travelling page 13 up inclines where more traction was needed, an extra person travelled on the toboggan. Because very low speeds were used on the Taylor Glacier, spark-plugs oiled up rapidly and needed regular cleaning/replacement. Because of this and the poor idling characteristics it was difficult to maintain a slow regular speed, which could only be achieved by constantly working the throttle. The entire trip was downhill from Depot Nunatak to the snout apart from short excursions to the Beacon and Pearse tongues of the glacier. Thus it was possible to haul two sledges with a total load of up to 1400 lb. Control was improved considerably by shortening the tow lines between sledges and between the toboggan and sledges to minimise fish-tailing. Ice clots were very necessary in these conditions.

A petrol allowance of 8 mpg proved more than adequate particularly on the Taylor where most of the travel was slow and downhill. A toboggan cover was used on the Taylor Glacier to keep snow etc. out of the stationary toboggan. This performed satisfactorily although only moderate winds and light snow falls were experienced. Covers were not available for the Cape Royds trip. One modification which proved useful was the fitting of a rear-vision mirror to No. 24. This avoided the problem of turning to check on the load being towed when wearing heavy down gear.

The toboggans we used performed satisfactorily with no major difficulties, a large factor in this was probably the thorough checking and tuning they received at Scott Base before departure from Jos Lang and Barry Hiscock.

(b) Sledges

Event 12 went into the field with two sledges (1 dog sledge and one of the new 'red' sledges). Both withstood the conditions exceptionally well. The red sledge was handed over to Event 13 on Nov 20 at Depot Nunatak. Minor repairs had to be made to this sledge. Twine lashing and doping of a split outside longitudinal, which was damaged during a downslope manoevre on extremely smooth ice. The sledge and toboggan were going directly down a low gradient slope. The driver turned slightly causing the sledge to swing out catching up with the toboggan and eventually hitting a small snow patch and 'broadsiding' over. The sledge was fully laden and had a brake-man. Unfortunately, because this sledge lacked dog sledge handles and stand, braking by the brake-man proved ineffective against this rapid swinging out motion.

Other damage was minor (a) one leather lashing between the first bridge and runner was replaced; (b) abrasion of front cow-catchers, resulting from contact with the toboggan.

The sledge tanks appeared to have canvas sidings of poor quality. The dog sledge siding canvas continually ripped along eyelet holes and hook rivets. This was simply the result of badly deteriorated canvas. However, the red sledge had a new sledge tank and canvas sidings. This too ripped at the eyelet holes, on inspection these sidings did not have extra strengthening along the margin. Canvas siding failure was due to age and poor manufacture. Repairs seemed impractical, further ripping was prevented by loosely tying the canvas sidings, when loading, and increasing the main sledge lashings.

page 14

Event 13

One dog sledge and one combination Nansen sledge were used on the Royds trip. Both had sledge tanks. No problems or breakages occurred. The same dog sled was taken into the Taylor, no transport difficulties were experienced in helicopter loading despite the difficulty in keeping the sledge runner away from the lugs projecting below the helo cabin, and keeping the handlebars clear of the ground when landing. At Depot Nunatak we also obtained the red sledge with the brake from Event 12. The dog sledge had both brake and keels although the keels were not used on the hard glacier ice.

The only repairs necessary were to replace the lashings and straighten and lighten the bolts on the brake bars. Brakes received extensive use because of the amount of downhill travel. Rope brakes fitted on the rear sledge were used for brief spells but have a very short life and were conserved carefully. Sled tanks were used with both sledges, one required the patching of a tear at the Beacon Valley.

(c) Air transport to, from and in the field was provided by U.S. Navy helicopter.

B. Main areas covered and routes

(a) Event 12

Event 12 spent all of the 12 weeks field work on or close to the Taylor Glacier. Travel was mainly by motor toboggan and supplemented by helicopter and foot. Because of previous experience in this area no major movement problems were encountered. Two areas of heavy crevassing (near Finger Mt. and Depot Nunatak) were negotiated on several occasions but obvious routes were found.

On three occasions access off the glacier required fixed ropes (Beacon Valley, Pearse Valley and around the snout). Abseiling and jumaring were the techniques used. In this aspect, as well as general glacier travel, experienced field personnel (Walter Fowlie, Colin Monteath and Jos Lang) proved invaluable.

(b) Event 13

The coastal route to Cape Royds is well known, we generally experienced good travelling conditions although some sastrugi were encountered between Cape Evans and Royds. Generally well compacted snow covered the sea-ice for much of the journey. Travel on the Taylor Glacier was much more varied and demanding. We were put down at Depot Nunatak - meeting briefly with Event 12. Circumnavigation of Depot Nunatak revealed a heavily crevassed region to the North making toboggan page 15 travel somewhat hazardous and requiring much caution. Crevasses however, were clearly visible in the blue glacier ice. From Depot Nunatak down glacier to the Kennar Valley further heavily crevassed areas were encountered and travel was slow, again requiring extreme care. Below the Kennar Valley no problems of this type were encountered and between the Kennar Valley and the Beacon Valley the glacier was covered with compacted snow. Aerial photos from Event 12 and local knowledge were very useful in route finding.

The glacier margins were steep at the Beacon and Pearse making the use of ropes and prussics essential for access to the valleys, no problems were encountered getting on and off at the snout.

In the Wright Valley we were landed in Tyrol Valley between Mts Baldr and Thor and journeyed by foot down through the Labyrinth into the South Fork and eventually to Vanda. The terrain was easy and access to areas of interest particularly around the Upper Labyrinth was no problem. The next base was established on the Olympus Range beneath Mt Dido. A single Meade tent was found sufficient for the conditions encountered.

After working from this camp for several days we returned to Vanda via the North Fork of the Wright Valley. Access to the North Fork is not difficult below Mt Dido.

After Christmas we travelled via Bull Pass to a previously established camp at Lake Vida. From this camp at the west end of the lake we made several trips of several days duration, to the lower Olympus Range (Mt Cerberus) and to the Upper Victoria Glacier. Access onto the glacier was via a frozen waterfall on the south-west side of the glacier. This was the only viable access-point we found on the lower reaches of the glacier.

(c) Event 25

Field work was restricted to areas within the Quartermain Mountains. The initial field work within Kennar Valley was carried out on outcrop within walking distance of the main camp.

Finger Mountain camp was on the saddle directly below and to the southeast of Finger Mt summit. On the initial helicopter flight in, a food dump was laid on the saddle. Camp was established on foot from Kennar Valley and on completion a return to the main Kennar Camp was also made on foot.

Work in the cirque valleys between Kennar Valley and Tabular Mountain was done on foot.

Two further areas (Mt Feather and Upper Beacon Valley) worked, were visited by helicopter.

page 16

C. Weather

Detailed meteorological observations were not taken due to: (1) the lack of instruments and (2) closeness of working parties to Vanda Station and Scott Base. A record of the morning visual weather report to Scott Base was kept by Events 12 and 13.

Weather conditions on the Taylor Glacier were excellent with only one day of bad weather out of the twelve. Only moderate winds were experienced and air temperatures were around −25°C −30°C with −30°C recorded on one day at Depot Nunatak in blizzard conditions.

On leaving the Taylor Event 13 we were stranded for three days at Marble Pt together with the crew of the helicopter Gentle 15. This culminated in a return to Scott Base, so a scheduled 1 hr shift into the Wright Valley became 6 days. In the Wright and the Victoria Valleys the typical katabatic winds occasionally restricted activity but loss of time was still only one day in eight. At Lake Vida in particular, a regular wind cycle observed each day, winds generally from the East building up mid-morning and dropping soon after midnight.

D. Communications

There were few communication problems. Compak 8 radios were used by all VUWAE Events and performed very satisfactorily. Battery life was somewhat variable with rapid tail-off being experienced with the Ni-Cd cells. Events 13 and 25 were very fortunate to be provided with lightweight lithium cells while travelling on foot shifting camps down the Upper Wright Valley, Olympus Range and Finger Mt. The weight advantage is considerable with a reduction of at least a third in radio weight. Detailed transmission and receiving times were recorded and returned to the Post Office at Scott Base. The life of these battery packs was exceptional. Traffic was kept to a minimum when using the lithium batteries and they were used for a total of twenty-one days by Event 13 at various stages of the field work.

On only one day was communication with Scott Base or Vanda impossible, although relaying via Vanda was used on several occasions. The primary frequency of 5400 was used on all but five to six days. In this the reception was poor at Scott Base, but in the field, reception was generally excellent.

At Marble Pt., the Event 13 radio was used entirely to communicate with Scott Base who then relayed messages via telephone to McMurdo. McMurdo could not be raised with any of the helicopter radios, proving how vulnerable cummunications are for the helicopter crews when the machine is on the ground.

Scott Base supplied good radio service, thanks to John Lythgoe (main skeds and music); Mike Bradstock and Trish Harris (news); Paul Dennison and Simon Cook-Willis (radio servicing and repairs).

page 17

E. Loss/Damage of Equipment

No major loss or damage occurred to toboggans, sledges or tents, on the Ross Island or Taylor Glacier section of the expedition.

Minor patching of one of the Meade tents was carried out at Vanda. These tents seemed particularly vulnerable in moderate to high winds and camp sites were chosen to minimise this.

A new relatively lightweight Polar tent was used extensively by the expedition and performed adequately although by the end of the season there were areas of patches reinforcing where the stitching was pulling away.

F. Recommendations

(a)After two field seasons dependent on motor toboggans, personnel of Event 12 considered that the best type of toboggan would be a combination of a 4-stroke engine with OMC bodies. The reasons being (i) good 4-stroke engine performance under cold conditions, (ii) slower idling speed of 4-strokes enables better and safer manoeuvrability in rough and crevassed ice areas, also better traction on flat icy surfaces and (iii) the stronger construction of the OMC body, tracking and suspension.
(b)

Sledging on icy surfaces requires a lot of 'sledge braking'. Experience indicates the full dog sledge to be far superior in its braking abilities. The handles and stand, plus foot brake enable confident and speedy travel even with full loads and difficult terrain.

Shorter sledge towing ropes are suggested. This is a necessity during downglacier travel and double-sledging. Towing ropes which can be rapidly adjusted to suit snow and ice conditions, would enable better handling of sledges. This would prevent major damage to sledges as it reduces the amount of 'jack-knifing' of towed sledges.

(c)Unpleasant quantities of kerosene fumes with possibly some carbon monoxide were experienced in the early stages of the season from the new VUW primuses which had in fact, been tested and double filtered fuel used. Defective washers proved to be the main offenders and showed the necessity for careful checking, particularly when being used in poorly ventilated conditions such as in tents.
(d)A potentially dangerous primus fuel mixup occurred with containers of DFA being forwarded to Vanda. These were not the containers left on the pad at Scott Base and as small containers were at a premium it is possible the original kero was "borrowed" from the resupply stockpile, and replaced later. Such a practice should not be encouraged.page 18
(e)Toboggan rear-vision mirrors can be relatively easily rigged up by field parties who want them and are extremely useful as a large part of tobogganing time is pulling loads.
(f)As previously mentioned, the helos should carry radios which provide effective communication with McMurdo whilst the helo is on the ground.

G. Personnel

Once again Victoria University expedition members completed a scientifically successful season. This success could only be attributed to the keeness and dedication of DSIR personnel, especially the field staff; 'Poma' Palmer, Nigel Nalder, Walter Fowlie, Jos Lang, Max Wendon and Colin Monteath.

To single out any one would be impossible. Each field assistant approached their tasks with a vigour equal to, if not greater than, the expedition members with whom they were working.