As I might be the "source" of this question, or at least one of the sources, her we go! ;-)
Your question holds a postulate: "Vikings rowed in shifts....". We do not actually know this, but my theory which I presented in a Danish daily newspaper on the 26th of January 1998 ( http://www.information.dk/16162 , later on the internet http://www.abc.se/~pa/publ/vikskift.htm and still later in English http://www.abc.se/~pa/publ/vikshift.htm ), I argued that there is a lingual connection between "rowing in shift" and the noun "viking". What is indisputeable is, that there in Northern Europe is an old sea measure, which means the distance between shifting rowers. In Low German this measure is called "Weke Sees", in Old Norse "vika sjóvar", in Danish "uge søs", in Norwegian "ukesøs", in Swedish both "veckusjö" and "sjövika". The Dutch and e. g. the Wends most likely have had their own names for this sea measure! The arguing is that from ON "vik" (the Eng. noun "turn" or "shift") is "vikja" (the Eng. verb "turn" or "shift") derived. From that the ON activity noun "viking" (the Eng. "turning" or shifting") is derived and from that the ON noun "vikingr" (the man who performed the "viking" activity) is derived! Compare with e. g. "sail" (the noun) => "sail" (the verb) => "sailing" => "sailor"!
Even if ON "vikingr" thus means "a man undertaking a long voyage", we don't today know how old and "archaic" the connection between ON "vik" and ON "vikingr" was at the period of time, which we today call the "Viking Age"! In this area people were rarely literate and it is quite possible that the vikings (the pirates) had no knowledge of the etymology of the ON "vikingr"!
Some years after I had written my article on this subject, I learnt that the Swedish admiral and chamberlain Bertil Daggfeldt had written this article http://fornvannen.se/pdf/1980talet/1983_092.pdf already 1983. Daggfeldt's article were very little spread among Swedish philoIogists and no one really understood how important it was. I contacted Bertil Daggfeldt and got his permission to also put his article on the net ( http://www.abc.se/~pa/publ/vik-rodd.htm . Later I also translated his article in to English, http://www.abc.se/~pa/publ/vik-oar.htm , and after that philologists from many countries began discussing the rower shifting etymology seriously!
So returning to your question! The viking ships, both the long boat and other types could be propelled by rowers alone; this was a great advantage in critical situations, but normally the vikings sailed or waited for favourable winds. In those cases, where the ship was propelled by oars, one has to consider the length of th ON "vika sjóvar". The shift would then probably have been two hours; Scolars have also been postulating that a shift was 1000 oar strokes, but this is not documented!
John Larsson, Hillerød, Denmark ( jodalela@gmail.com )
Icelandic would be the language most similar to the language of the vikings. Swedish slang for hello include: Tja and Tjena.
Franks, Moors, English, each other including the Normans (Vikings who had relocated to France), various peoples in the Mediterranean and Russia, and some even clashed with a native tribe in North America. The Vikings encountered no shortage of enemies.
The vikings were not a collective whole. There were Norwegians, Icelanders, Danish, and many others. Some were allied with each other, some were enemies of each other. Egil Skalagrimson who was known to have gone aviking was the enemy of the King of Norway, for example.
"The Minnesota Vikings will play the Chicago Bears on the afternoon of Sunday, October 16, 2011. The two teams play each other at Soldier Field in Chicago, Illinois."
Clinker building: overlapping planks fastened to each with iron nails/rivets
it shifts to the rightt!
Beginning of each shift
It is available to you automatically each time you start your vehicle. Unless turned off it is the final gear your car shifts to at approximately 40mph+ while cruising, (if the petal is to the floor it will not shift to O.D. but rather if your going above 40mph and decide to pass the first thing your auto transmission will do is shift from your O.D.).
TDM
Vikings were unique individuals, just like humans now. Each one had his or her own unique abilities and talents.
In Scandinavia, against each other. And in Britain.
When driving a stick shift, you shift up as the engine begins to rev in each gear. You will downshift as the engine begins to slow.
Vikings. They have the only playoff win against each other and that is all that matters
Icelandic would be the language most similar to the language of the vikings. Swedish slang for hello include: Tja and Tjena.
The shift cable has failed.
The Broncos, the Bills, and the Vikings.
Through the 2012 season, the New York Giants and Minnesota Vikings have played each other 25 times. This includes the playoffs.