Fix accuracy: 0.05 nautical miles plus 0.2 NM per knot of speed error (RMS). 
Fully automatic, computer controlled tuning. 
The satellite navigation equipment functioned to perfect satisfaction and 
was, according to the ship's captain, Navy Captain Anders Billsträm, of great 
importance for the planned activities in the ice-covered regions, especially 
as the charts sometimes were completely incorrect. 
The European Space Agency (ESA) and the Swedish Delegation of Space Activi- 
ties provided the YMER-expedition with Landsat-pictures. The satellite trans- 
missions were received at the SSC's (Swedish Space Corporation) station Esrange 
at Kiruna in the north of Sweden. From Kiruna the pictures were forwarded by 
wire to the naval coast radio station Alvsborg radio and from there over the 
wireless to "Ymer". In addition, the ship was also fitted with a telecopier for 
ice charts. Twice a week "Ymer" received a compilation of the ice situation from 
the Naval Polar Oceanography Center, Washington, D.C., U.S.A. Carefully studied 
were also ice situation charts, published by the Norwegian Meteorologic Insti- 
tute. Ice forecasts, made by a Norwegian and a Swedish meteorologist aboard the 
ship, were likewise of great value. 
For night navigation the vessel is fitted with 5 remotely controlled Xenon 
searchlights: two 900 W units are fitted below the bridge wings, two 450 W units 
are mounted on each side of 3rd Bridge deck and one 450 W unit is mounted aft. 
The lights have "joy-stick" controls from the bridge. Further, there were spe- 
cial electronics for accurate position fixing, satellite communication equipment 
(to the MARISAT system), weather/ice telefax etc., echo-sounder for very deep 
water, a variety of hydrographic instruments, deep-sea winches, equipment for 
bottom sampling, chemical, physical and geologic research, hydrocopter and an 
all-terrain vehicle of Hägglund 206-type, and a good deal of other equipment. 
The aim of the Ship-Technology-Program during the later part of YMER's High 
Arctic expedition was exclusively to determine the ability of the ship to oper- 
ate under arctic conditions. The program was carried out by Gótaverken Arendal 
(Gothenburg, Sweden) and consisted of several subsections, among others "Testing 
of night vision equipment as navigational aids". 
For recording ice conditions and the performance of "Ymer" a low light level 
TV-camera (RCA TC 1006), in a environment-resistant sealed housing, was installed 
on top of the wheelhouse. The camera was fitted with a 12.5 mm lens, giving a 
good over-all view of the ice field ahead of the stem. A RCA TC 3450X Recorder, 
with time/date generator and time-lapse capability, together with a RCA TC 1209 
video monitor were placed in the wheelhouse. On the monitor a specially cali- 
brated grid was fitted, giving distances forward of the bow. This facility pro- 
vided the possibility of determining the ship's speed using the timing on the 
screen. Use of the time-lapse video recorder allowed up to 24 hours of video in- 
formation to be stored on 120 minutes tape. An additional monitor was also pro- 
vided in an instrumentation container on 3rd Bridge deck. During the latter part 
of the voyage an additional TV-camera was tested for the purpose of detecting 
ice in open water. 
Beside the fixed TV-camera installation for the recording of the progress 
of "Ymer" through the polar ice, a very low light level camera was tested aim- 
ing at early detection of ice in darkness. The camera used was a RCA TC 1030/H10 
with zoom lens 16-160 mm (10X) f/1.8 with a TC 1430 controller. This camera gave 
useful pictures with as little light as quarter moonlight. The camera was mount- 
ed on a tripod on the bridge. Floating ice, with floes varying from about 5-10 m 
across, was easily spotted at distances of 1200 to 2000 m in cloudy night condi- 
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