( Log In ) Log In is for TREC Teachers & Researchers only

Reply to this topicStart new topic
> 9-18-05: We Need to Move South, The Freeze Up Has Started.
post Sep 20 2005, 12:09 AM
Post #1

TREC Teacher

Group: TREC Team
Posts: 203
Joined: 27-April 05
Member No.: 10

We need to move south - The freeze up has started
TREC 9-18-05

Ship Position at 2005/09/17 23:37:01 UTC
Longitude: 58 54.656 E Latitude: 87 6.666 N
"IBCAO" depth: 3752 m Heading: 187.4 Water Temp: -1.797 Sal: 32.63

The temperatures dropped again (-15C to -17), the deck is covered with ice and snow. The sun is very, very low on the horizon. The Arctic winter is coming. We have to break ice! Constant vibrations followed by the screechy noise and sometimes a loud bang of ice against the hulls are a clear sign of a fast freeze up of Arctic waters. High winds, fog, blowing snow, low visibility and an ice drift to the north make matters worse. We made only 30 miles south in one day! Open leads that the Oden helicopter has spotted are long closed before we reach them. The ice is under pressure which makes backing and ramming difficult.
IPB Image
The Healy clearly slid on top of heavy ice during the ramming.
IPB Image
Backing icebreaking sequence of the Healy
IPB Image
Things freeze on deck almost instantly.

The Healy breaks the ice by ramming against it and sliding on top of it to break it by the mass of the ship. The more momentum we have the better. Physics one to one, momentum is mass times velocity. The ship gains speed by driving backward in the channel that it just broke called “backing”, it stops, reverses the engines and starts accelerating forward to gain speed for “ramming” the ice (F*t = change in momentum). If we can't backup far enough because the ice closes behind us, we cannot gain the momentum we need to ram ahead and up onto the ice to break it. In other words, there is not enough time to accelerate and to gain speed. In addition, there have been problems with one of the two cycloconvertors that control the frequency/rpm for the motors of the two shafts which turn the two ship propellers. This reduces our power and ability to turn.
IPB Image
MKCS J. Bisson showed me the cycloconverter area.
IPB Image
EM1 B. Jolping works on the Cycloconverter
IPB Image
EMC F. Donze changes electronic parts.

Today (9-17-05) the science chiefs from the Oden and the Healy and the Captains of the ships held a planning meeting on Healy to assess the situation. Dennis Darby said: “It was announced that Capt. Arnell wishes to proceed south without staying on the Gakkel Ridge to complete the multi channel seismic surveys. Capt. Oliver has decided that he would be jeopardizing Healy by staying in these ice conditions this far north and this late in the season alone. The project leaders concur completely, so we will accompany Oden south. We are still hopeful that we can stop long enough on the Gakkel Ridge to take a quick gravity core near the summit of what appears to be a very young volcano extending to within about 350 meters of the surface.” Well, the Arctic shows us who is really in charge here. We need to move south fast if we won’t risk to get stuck here for the winter.
IPB Image
Snow storm and low visibility. I took the photo of the Healy from the icebreaker Oden, 9-17-05

One the lighter site we just had a pipe (announcement over the ships speaker system) that 3 Polar bears are close to the bow of the ship. Yes, 150 m from us a mother bear with her two cubs were gracefully walking over the vast ice field. They looked at us wondering what we are doing here in their frozen realm …
IPB Image

Everybody is well,
Ute Kaden
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:


- NSF Acknowledgment & Disclaimer Time is now: 25th February 2018 - 01:30 AM
IPS Driver Error  

There appears to be an error with the database.
You can try to refresh the page by clicking here.

Error Returned

We apologise for any inconvenience