Nicole Taylor, ZS1NCT, the daughter of our HAMNET Regional Director, Michael, ZS1MJT, has a Masters in Mechatronic Engineering, and is writing a blog from her position now, on board SA Agulhas ll, doing research into stresses the ship experiences as it plows through the ice down at Antarctica. She has written a description this week of the tricks the ship uses to break free, or break a channel through the ice. She says:
”It helps to know that the SA Agulhas II is an ice-going vessel with a strengthened hull that makes her really great at taking on ice head-on. She does this by pushing ice cakes aside with her bow or, when the ice cakes are very big (so they have formed an ice floe or sheet), sliding on top of the ice as she goes forward and breaking the ice below her belly with her weight. She ends up cracking through the ice below her and then nudging the broken ice aside as she trudges on forward.
“At times, however, the snow gets really thick, which weakens her ice-sliding, -nudging and -cracking superpower. The snow acts like glue and holds her tight, which requires extra effort from the crew to get free from its grip. First up is Plan A.
“Plan A: Try the propulsion system. I.e. Try to reverse out and push forward using the propellers to see if the snow-grip can be overcome by the engines. If this does not work, try Plan B too.
“Plan B: Pump water between port (left of ship if you are on the ship and looking towards her front) and starboard (right of the ship) side ballast tanks, which are massive water tanks. This helps shift the ship’s weight between left and right, slowly trying to loosen the snow-grip. If this does not work, the big guns start coming out in Plan C.
“Plan C: Rotate the front crane arm, rated at 35 tons – so it’s a big one – between port and starboard side. This is similar to Plan B, with more weight being shifted around. This is usually done in conjunction with Plan A and B, if they alone do not work, to shift more weight around while trying to move out of the ice.
“And if this does not work, a jacked up Plan C becomes Plan D: Rotate the front crane arm between port and starboard side while holding a 20 ton container. This is also usually done in conjunction with Plan A and B.
“Then, at play behind the scenes is always Plan E: Get help from the ever-changing environmental conditions that help loosen the ice, or melt the snow, etc. This can mean waiting for warmer weather (anything in the positive degrees C range would be great) to help melt snow and ice, or changes in tides and strong winds that blow the sea ice away or loosen it. Sometimes a good night’s rest on board while the ship rests in the ice offers just the right amount of time for Plan E to do its thing to let Plan A work first thing in the morning.
“The ice in Antarctica this summer season sure offered the SA Agulhas II a fantastic platform to showcase her ice-breaking ability. Although it sometimes appears as though her favourite game to play is “stuck in the ice”, the SA Agulhas II, piloted and manoeuvred by her experienced crew, always has a good few plans up her sleeve and does a great deal to break through the ice we encounter – what an experience to have front row seats to all this!”
You can follow Nicole’s blog by typing this and only this into your search engine:
https://expeditionantarctica.wordpress.com/author/zs1nct/
Thanks very much for this and permission to publish, Nicole! What a very clear description from a competent young lady, who, by the way, is also a member of HAMNET.
Our Western Cape HAMNET bulletin relay on a Wednesday night at 19h30 CAT has been augmented by a link, off the Echolink relay, on to DMR Brandmeister Talk Group 6558, done by James ZS1RBT, using his personal DMR ID. So if you have that DMR capability, join us on Wednesday evenings for some news and views. The relay is one-way, because it is taken off Echolink, and not controlled by the bulletin reader.
In Kuala Lumpur, Indonesia, the Ministry of Communications and Multimedia (KKMM) is planning to use satellite technology to improve communication systems in the face of disasters, said its Deputy Minister Datuk Zahidi Zainul Abidin.
He said this improvement was to prevent telecommunication network disruptions during disasters, such as the situation experienced during the massive floods that hit the country last month.
He said the use of satellite technology, including 5G network satellites, could help to manage natural disaster situations such as sending early warnings to the public.
He said during flooding, communications were disrupted as calls could not be made due to power failures affecting telecommunication towers.
“The solution we need, is (to use) satellites…the government will discuss with countries that have (satellite technology) including 5G satellites. This is KKMM’s plan“, he said, adding the cost of using satellite technology was lower and the time to implement it was also shorter.
Thank you to TheSunDaily for this insert.
In ARRL News, this week, we learn that the TEVEL mission, which consists of eight satellites carrying amateur radio FM transponders, was set to launch on January 13 at 1525 UTC on the SpaceX Falcon 9 Transporter-3 mission, which also carries AMSAT-Spain’s (AMSAT-EA) EASAT-2 and HADES satellites. The TEVEL satellites were developed by the Herzliya Science Centre in Israel.
All eight satellites will use the same frequencies, as long as their footprints overlap, and only one FM transponder will be activated at a time. Beacon transmissions will be on 436.400 MHz (9,600 bps BPSK). The uplink frequency of the FM transponders is 145.970 MHz, and the downlink frequency is 436.400 MHz. The satellites were built by eight schools in different parts of Israel.
In fact, this SpaceX rocket was part of the rideshare programme, and launched a total of 105 satellites mostly in the Nano class, for a wide variety of agencies!
This reminds me rather of the vehicles of a very well-known South African online shopping experience, who’s drivers set off each morning from their despatch, with at least 100 small packages for delivery in their surrounds. Like SpaceX, their responsibility ends once the package (read satellite) is delivered to its destination.
This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.