Shipwreck Diving on Gunboat C-55, Isla Mujeres
Updated: Sep 3, 2022
USS Ransom (AM-283), named ARM Teniente Juan de la Barrera (C-55), is a shipwreck sunk off the coast of Cancun and Isla Mujeres for the sole purpose of diving. Located in the strong currents between the two land masses, she is a wreck suited for advanced divers all year round but annually, between December and March, is a place that Spotted Eagle Rays return.
This wreck is just a 25-minute boat ride from Isla Mujeres. Gunboat C-55 and Gunboat C-58 were both laid to rest on the sea floor, quite close to each other.
These two wrecks were sunk by the Mexican government, creating artificial reefs to be used for diving, and have proven to be a top destination for divers visiting the area.
The year-round currents caused by the proximity of the Cancun and Isla Mujeres land masses are very strong so these dives are not for beginners nor for divers that have not dived in a while. The depth of this wreck is around 22 meters /75 feet but the strong currents add an extra need for caution. The topography surrounding Gunboat C-55 is beautiful white sand and, just like Gunboat C-58, an area that was completely devoid of interest for the underwater visitor has been transformed into an amazing dive site with much biodiversity.
The History of the Wreck
C-55 Juan de la Barrera, sunk October 27, 2000
Unlike Gunboat C-58 which was so difficult to locate the history, Gunboat C-55 has so much information out there. She led a very interesting life.
USS Ransom (AM 283) was an Admiral-class minesweeper built for the United States Navy during World War II. She was awarded three battle stars for service in the Pacific during World War II.
United States military Career
24 April 1943; Built by General Engineering and Dry Dock Company as an Admiral-class minesweeper.
18 September 1943; Launched as USS Ransom (AM-283), sponsored by Mrs. Dwight H. Dexter
5 August 1944; Commissioned in U.S.Navy (USN) with Lt. Comdr. William N. McMillen in command and conducted a shake down cruise off California.
15 October 1944; She proceeded to Hawaii, arriving at Pearl Harbour a week later. She did escort duty back to the west coast and later to Eniwetok, Ulithi, and Kossol Roads, arriving at the latter on 12 January 1945. She then worked in the antisubmarine patrol screen off Peleliu.
1-18 February 1945; Ransom acted as harbor entrance station vessel at Kossol, and patrolled in screens between Kossol and Peleliu, before proceeding to Ulithi to stage for Operation Iceberg.
19 March 1945; She sailed for the Ryukyus with task unit TU 52.5.3
25 March to 18 April 1945; She swept and patrolled in assigned areas around Okinawa despite heavy Japanese coastal and aerial resistance
6 April 1945; Ransom shot down three suicide aircraft while rescuing 52 survivors of USS Rodman (DMS-21) and USS Emmons (DMS-22). The third kamikazes bomb caused some minor damage to Ransom.
18 April 1945; Relieved of sweeping duties, Ransom was assigned to antiaircraft and antisubmarine patrol. Although damaged on 22nd by a bomb from a “Val” she had splashed 10 feet off her port quarter, Ransom continued to patrol through June.
4th July 1945; Ransom resumed minesweeping operations. Throughout the month she operated in the East China Sea, sweeping a total of 7 mines
6 August 1945; she retired to Leyte for overhaul and repair. Returning to Okinawa at the end of the month, she continued to Japan with task group TG 52.4
9 September 1945; began sweeping mines at Nagasaki.
2 September 1945; she shifted to Bungo Suido, where she swept until the end of September. During the month, Ransom swept 73 enemy mines. Ransom departed Kure, Japan, for the United States on 20 November.
30 December 1945; Transiting the Panama Canal, she continued onto New Orleans, Louisiana; underwent pre-inactivation overhaul; and decommissioned at Orange, Texas, 3 March 1947
March 1951 Ransom was recommissioned during the Korean war and remained in commission until September 1953, when she was, again, placed in reserve.
February 1955; While she remained in reserve, Ransom was reclassified as MSG-283 but never reactivated.
1 May 1962; Struck from the naval register
1962; She was sold to the Mexican Navy.
Mexican Navy career
1962; The former Ransom was acquired by the Mexican Navy and renamed ARM DM-12.
1994; she was renamed ARM Teniente Juan de la Barrera (C-55) after Juan de la Barrera.
She was stricken in 2000, but her fate was to become a dive site on Isla Mujeres
27 October 2000; She was sunk by the then Mexican President Ernesto Zedillo with the intention of becoming an artificial reef for diving.
The wreck lies at a depth of 22 meters/ 75 feet.
On 21-22 of October 2005, Hurricane Wilma impacted the area as a Category 4 hurricane. The hurricane broke the shipwreck into pieces leaving only the aft (stern) section upright and intact on the sandy bottom. This is the only section of the wreck that permits light diver penetration.
There is generally a descent line attached to this section, although, like Gunboat C-58, boats may no longer tie up to this line. The stern can be appreciated resting on its left (port) side.
Pieces of the engine can be seen around the wreck, scattered along the sea floor.
The bow of the boat is located close by and has tiny windows along the side.
Displacement 945 t.(fl)
Length 184' 6"
Draft 9' 9"
Speed 14.8 kts.
Armament: One 3"/50 dual purpose mount, one twin 40mm gun mount, six 20mm gun mounts, one depth charge projector (hedgehog), four depth charge projectors (K-guns), and two depth charge tracks
Propulsion: Two 1,710shp Cooper Bessemer GSB-8 diesel engines, National Supply Co. single reduction gear, two shafts.
Spotted Eagle Ray Season
As with Gunboat C-58, this shipwreck is the return destination for the annual migration of Spotted Eagle Rays.
Being the lesser dived of the two wrecks, it can be a great opportunity to see the large numbers of these creatures undisturbed by other divers.
The Spotted Eagle Rays return every year to frolic, eat and mate in the strong currents that are the trademark of this dive. It is not uncommon for divers to see 50-100 of these magnificent animals gliding peacefully but closely overhead.
The white sand and the shallower depth allow for some great photos to be taken here, both of the wreck and of the marine life (although a red filter or white balance will still make a significant difference to your photos).
So much marine life now exists in this once barren area. Artificial reefs create such an impact on the biodiversity of an area and Gunboat C-55 is no exception.
This shipwreck is home to nurse sharks, rays, eels, jacks, barracudas, groupers, sardines, and parrotfish.
Small crustaceans have made their home in the shipwreck and corals and sponges have attached themselves to the sides.
This dive is an advanced dive and should be treated as such. The very strong currents and depth mean that divers must have experience before attempting this dive. A strict screening process applies to be able to participate in this dive for the safety of both the diver and the guide.
While there is generally a line available for descents, boats are no longer able to tie up to this as we mentioned previously. So the entry to this dive is by a negative entry, backward roll. Divers can then free-descent to the bottom or swim to the descent line and use it to help them to the bottom. Divers must be secure in their ears and in their diving skills.
Your ability to listen to your guide and be a good buddy to your diving partner will mean that everyone has a great, safe, and fun dive.
The normal dive time for this dive is around 30-35 minutes and a safety stop is a necessity.
Although there is a descent line, the shipwrecks are located in the open ocean. Therefore a DSMB is a crucial piece of dive equipment for both alerting other boats of your position and helping you maintain safe diving practices such as slow ascent rates and safety stops (although you should be able to do this without a line too).
22 meters / 75 feet
Required Experience Level
Advanced Open Water Certified Diver / Experienced Diver
Average Underwater Visibility
20 meters / 65 feet
Average Water Temp
26 Cº / 79 F°
Normal Dive Time
30-35 minutes (safety stop required)
To view the fish surveyed here with reef.org click HERE
PacificWrecks.com. (2022, April 23). Pacific Wrecks - USS Ransom (AM-283/MSF-283) ARM DM-12 / ARM Teniente Juan de la Barrera C55. Pacific Wrecks. https://pacificwrecks.com/ships/usn/AM-283-.html
Ransom (MSF 283). (1996). Navsource Naval History. http://www.navsource.org/archives/11/02283.htm
USS Ransom (AM 283) of the US Navy - American Minesweeper of the Admirable class - Allied Warships of WWII - uboat.net. (1995). Uboat.Net. https://uboat.net/allies/warships/ship/5933.html
Wikipedia contributors. (2022, February 15). USS Ransom (AM-283). Wikipedia. https://en.wikipedia.org/wiki/USS_Ransom_(AM-283)