"City"-class gunboats' speed

Billy1977

Sergeant
Joined
Mar 18, 2016
Location
Flippin, Arkansas (near Yellville)
Hello everybody, I've been reading up a little on the Union's "City"-class gunboats (Cairo, Carondelet, Pittsburgh, Mound City etc.) on the Mississippi River and have found conflicting information regarding their top speed. Some sources say 4 knots, some say 6 knots and some say 8 knots. In Official Records, Navies in their statistical data of U.S. and C.S. ships it says for Carondelet that she could go "upstream, 4 knots"

http://ebooks.library.cornell.edu/cgi/t/text/pageviewer-idx?c=moawar;cc=moawar;idno=ofre2001;node=ofre2001:2;view=image;seq=58;size=100;page=root

so I'm thinking maybe the sources that say their top speed was 4 knots are referring to them being able to go upstream no faster than 4 knots. What would have been their top speed going downstream then? Maybe 6 knots? What would be considered the definitive source for this kind of Civil War naval data?
 
Last edited:
Mark can probably address this more directly, but assessing speed on the Mississippi and its tributaries is tricky because the flow of the river is constant and affects a vessel underway. The speed of the Mississippi is typically between 1.5 and 3 miles per hour, but can be significantly faster at times. Distances on the inland waterways are generally measured in statue miles, rather than nautical miles, so that's another wrinkle in the calculation.

In seagoing ships, trial speed is usually determined over a standard course between fixed points. The course is run in both directions to account for wind and current, and the official trial speed is considered to be the average of the two. I should think something like that was done on the rivers, but I am unfamiliar with the specifics.
 
Attached is a master's thesis by Lieutenant Commander Nicholas F. Budd, USN, from the U.S. Army Command and General Staff College (1997). In several places he discusses vessel speed in the unique context of the rivers (see beginning p. 18):

The speed of the current on the Mississippi and her tributaries varied greatly with season,
stage (water level) and pilot-selected channel. The path a river pilot selected when navigating
between two points varied depending on conditions on the river. He endeavored to choose the
shortest path consistent with his vessel's draft, and to steam against the weakest current he could
find. Conversely, steaming downriver, he would take advantage of the current to increase his
speed.

The best powerplants of the era propelled the fastest of the era's steamboats at sustained
speeds approaching fifteen miles per hour. The fastest passage on official record between New
Orleans and Cairo, Illinois, was three days and one hour, yielding an average speed of a little
better than fourteen miles per hour. The vessel was the famous MV Robert E. Lee and the record
was set on the occasion of a race between the Lee and the MV Natchez. Both vessels were
lightened, optimally trimmed and were steamed with plants operating at pressures higher than
considered normal for the sake of safety.

River vessels operated under conditions where speed was essential for commercial
success. For a fast river transit, owners relied more heavily on the vessel's pilot selecting an
optimum route than on the muscle provided by its powerplant. Military vessels utilized these
same powerplants fitted into hulls vastly heavier for their dimensions than their commercial
counterparts. As a result the military vessels suffered from inferior speed and maneuverability.


Although he doesn't address the exact speed of the City Class vessels directly, Budd asserts that the older "timberclads" were preferred n situations where speed and maneuverability were critical.

8758294282_bc68f82274_h.jpg
 

Attachments

  • Riverine Warfare.pdf
    4.6 MB · Views: 592
Last edited:
The speed of the Pook Turtles? Consider their nickname... :wink:

The modern concept of a speed trial wasn't really in place at the time; certainly not on the western rivers. A riverboat naturally had to have enough power/speed to stem the river's current, else its usefulness was limited. The deep-water method of measuring speed (casting the log) wasn't done (or at least wasn't done on a regular basis) on the rivers, any more than draft horses were timed for what speed they could make with this or that cart and load.

The current speed of the Mississippi in many areas was around 2-4 miles an hour on the average... but here's the catch: because of the physics of water flow, the speed is greatest about where the channel is deepest. Civilian riverboats going upstream would try to keep to the margins, where the adverse current was as weak as possible, whereas downstream boats would stand out in the middle*, both to avoid the upstream-bound boats and to make their best time-- time being money, of course. I don't doubt that the river gunboat pilots, all of whom who learned their trade in civilian boating, would have done precisely the same thing.

The reason I starred "middle" is because the deep/fast channel of the Mississippi constantly changes, much more so in the mid 19th Century before the Army Corps of Engineers really started working on the river in a major way. The deep/fast part of the river wasn't guaranteed to be in the same place on the upstream leg as it was on the downstream, let alone over more time than that. Add in the variable input of water to the system, resulting in higher/faster or lower/slower waters, and you can see that, even if we did have a standard measurement of maximum speed, it really wouldn't help us a great deal!

(And this is why good pilots were so highly prized and so highly paid... they had to know the river, not so much as memorizing a set of landmarks [though those had their value] as being able to "read" the state of the river and find the best course to take in any given circumstance. If there were two equally-fast boats, the one with the better pilot would make better time, all other things being equal.)

Sorry-- I see I echoed a number of points already covered in Andy's post! :redface:

Anyway, the general answer for the speed of the Pook Turtles is "slow." The Carondelet was generally considered the slowest of the bunch (though still better than the larger Benton), and the Cairo, by some accounts, was the fastest. I don't think the specific speed difference is given anywhere, but I'd guess we're talking about a variance in the neighborhood of a couple of miles an hour at most.
 
Thanks guys for the wealth of information and for the education about Mississippi River conditions. As someone who has only crossed over the Mississippi on a bridge one time I had no idea it varied that much by time of year, location etc. An experienced riverboat pilot sounds like he would be worth his weight in gold.

So it's safe to say that to refer to the "City"-class gunboats as being "quite slow" would be an accurate description of their speed?
 
Last edited:
Henry Walke took some space and time in his memoirs to extol the virtues of the river pilots and lament that they weren't more honored by their country-- especially because the pilot-house was such a dangerous post (often nicknamed the "slaughter-pen").

I find it interesting that one of the Benton's pilots was Horace Bixby, well-known to readers of Mark Twain's Life on the Mississippi as the first (and apparently most memorable) of the young Sam Clemens' instructors. If he was as good a pilot as Twain made him out to be, it's notable that he'd be posted to the most sluggish and unhandiest gunboat (which also frequently was the flagship)... it makes sense.
 
Back
Top