Talk:Flank speed

Because the word “flank” usually refers to the “side” of something, and because the earliest sailing warships had all their cannons facing either port or starboard, and even later WWI and WWII ships had the most firepower turned 90 degrees to the target, with nothing official to base this on, I always thought/assumed that ”flank speed” originally meant absolute maximum speed in order to position the ship asap to fire upon an enemy. Cec33333 (talk) 02:46, 27 December 2017 (UTC)

relative efficiency of LCS's flank speed vs. standard speed
In the example of the fuel efficiency of flank speed vs. standard speed, the LCS's range at standard speed is given at 4300 nautical miles, vs. 1500 nautical miles at flank speed. 4300 / 1500 = ~2.87, so how does this show that '"flank speed" consumes fuel over seven times faster than "standard speed"?' It looks to me that the example shows LCS's flank speed consuming fuel almost three times faster than standard speed. 24.75.111.12 (talk) 18:19, 7 May 2009 (UTC) Ed Denham


 * Three times as much fuel per mile, but since it's also going 2.5 times faster, fuel consumption per hour is 7.5 times higher. I agree it's confusing. Rees11 (talk) 15:18, 24 July 2009 (UTC)
 * @24.75.111.12 Being low on fuel limits where and how fast you can go before you run dry. Distance made good at any speed through water is affected by wind and  current directions and forces. 100.16.229.12 (talk) 14:25, 21 December 2022 (UTC)

Really need a new article on ship's speeds
I came here trying to find out what the various speeds mean. For example, is 2/3 twice as fast through the water as 1/3, or is it twice as many turns? What's the difference between standard and full? Flank and emergency? I think what's needed is an article explaining what each of these terms mean. Rees11 (talk) 15:21, 24 July 2009 (UTC)

origin of term
I came here with the vaguest idea that flank speed was fast. But why is it called "flank"? —EncMstr (talk) 20:42, 22 April 2012 (UTC)

yes I too came here for the same reason. I am watching the movie Midway. Why "flank"? 184.151.114.178 (talk) 18:41, 24 December 2013 (UTC)


 * My understanding, having been in the navy for 20 years, (and I can provide no reference for this) is that up until the Second World War the largest battleships had, in addition to the propulsion engines that drove the main propellers, smaller maneuvering engines that drove propellers on the outer port and starboard "flanks" of the ship. These flank engines didn't provide much speed, but were used to accelerate turns and aid in maneuvering in harbours/etc. Ships these days are generally smaller and mostly do not have flank engines, but you can see the vestiges of them on large aircraft carriers (here for instance). "Flank speed" just meant that in addition to going full speed on the ship's main propulsion engines, you would also try to squeeze out just a bit more speed by going full on the flank engines. This was wasteful in terms of fuel economy because it didn't add much speed, but could make the difference in an emergency. That is how the term came to now mean "as fast as physically possible". Geoff NoNick (talk) 04:58, 27 October 2016 (UTC)

Sustainability
added this to the article, but since it is unsourced and more of a discussion topic, I have moved it here:


 * The Above paragraph is partially incorrect. Although inefficient, it is NOT unsustainable, U.S. Navy Destroyers often traveled at full / flank speeds for a considerable time. One such Destroyer, The USS Rich DD-820 traveled all the way from Long Beach California to Subic Bay in the Philippines in 1968 on her way to Vietnam at 34 knots, full speed; only stopping briefly in Hawaii, Midway and Guam to refuel. The Rich was a steam powered Ship with four boilers and two steam turbine engines like most of that era and engine overheating was not an issue.


 * For example, the most economic speed of the Littoral combat ship is 20 kn providing a range of 4300 nmi,(Global Security: LCS specs) and endurance of 215 hours. This ship has a flank speed of 50 kn but can travel only 1500 nmi at flank speed, exhausting its fuel in 30 hours. Thus, its "flank speed" consumes fuel over seven times faster than the most economic speed.

—EncMstr (talk) 17:41, 21 November 2014 (UTC)