Flyaway Deep Ocean Salvage System Explained

The Flyaway Deep Ocean Salvage System (FADOSS) is a modular system used by the United States Navy to raise sunken objects, such as aircraft or small vessels. It has a maximum lifting capacity of, and can recover objects from depths of .

Design

FADOSS is operated by Naval Sea Systems Command, Supervisor of Salvage and Diving (SUPSALV). It is designed to be airlifted to sites and installed on a "vessel of opportunity" as required for rapid deployment. Installation includes welding to the ship's deck to support the load, which requires approximately 24 hours.^[1]

The major components of FADOSS include:^[2]

• Ship Motion Compensator (SMC)
• Traction Winch
• Take-up Storage Reel
• Hydraulic power unit
• Air compressor
• Air control manifold

The SMC is the key component, as it uses a pressurized ram cylinder and sheaves to compensate for ship motions, limiting the variance in line tension.^[2]

The recovery line and storage reel are sized for the job, and are available in,, and sizes.^[2] A remotely operated underwater vehicle (ROV) is used to locate the item(s) to be salvaged and attach rigging for recovery. After the recovery line is lowered to the site, the ROV attaches the line to the rigging and FADOSS uses the traction winch to reel in the line, lifting the object to the surface.

Operations

Development of the SMC began with testing a ram tensioner in the early 1980s;^{[3] [4]} the basic tensioner design had been used since the 1960s for underway replenishment operations, in which two ships moving next to each other transferred items by a horizontal line.^[5] By 1986, the system had been named FADOSS, capable of recovering items weighing up to from depths of ^[6] using an aramid-fiber line.^[7] FADOSS systems are stationed in Williamsburg, Virginia and Port Hueneme, California.^[8]

• A CH-46E Sea Knight was recovered off the coast of Somalia in May 1993 using FADOSS, mounted on .^[9]
• FADOSS lifted a hydrothermal vent nicknamed Roane from the Main Endeavour Field of the Juan de Fuca Ridge in 1998.^[10]
• A F-16 Falcon was recovered from a depth of near the coast of Japan using FADOSS in August 2012. Phoenix International Holdings was the contractor, operating from .^[11]
• A C-2A Greyhound that crashed in 2017 was recovered from the Philippine Sea in May 2019 by FADOSS, which was used because the estimated depth exceeded the on-site recovery depth capability of the United States Seventh Fleet.^[12] At the time, it was the deepest aircraft recovery.^[13]
• Parts from the wreck of a Royal Canadian Air Force CH-148 Cyclone helicopter were recovered from the Mediterranean Sea using FADOSS in June 2020, operating from .^[14]
• In March 2021, FADOSS was used to recover a MH-60S Seahawk helicopter from a depth of near Okinawa.^{[15] [16]} The salvage set a record for deepest airframe recovered. ROV CURV-21 was used to set the line and rigging.^[17] For that recovery, the system was welded to the deck of .
• FADOSS was used to recover a F-35 Lightning from the South China Sea in March 2022.^[18] The jet was recovered from a depth of approximately ;^[19] FADOSS operated from .
• An F/A-18 Super Hornet that was blown off the deck of during heavy weather was recovered by FADOSS from the Mediterranean Sea a month later in August 2022.^[20] The recovery depth was,^[21] using .^[22]

External links

• U.S. Navy emergency ship salvage material catalog (S0300-BV-CAT-010) . 1 . 1 April 1999 . Supervisor of Salvage & Diving, Naval Sea Systems Command.
• Web site: Operational salvage equipment distribution by location . 26 July 2022 . Supervisor of Salvage & Diving, Naval Sea Systems Command.

Notes and References

1. News: Navy's Deep Sea Salvage System Still In Port, At Least Day Away From Joining Titan Search . Trevithick, Joseph . June 21, 2013 . The Drive . 27 June 2023.
2. Web site: Flyaway Deep Ocean Salvage System . 8 September 2021 . United States Navy . 27 June 2023.
3. At-Sea Evaluation of a Ram Tensioner for Ocean Development and Recovery . September 1982 . Liu, F.C. . Sea, R. . 104 . 3 . Journal of Energy Resources Technology . ASME . 241–246 . 10.1115/1.3230410.
4. At-Sea Evaluation of Ship Motion Compensation Hoisting Devices . Liu, F.C. . Asher, R.C. . May 2–5, 1983 . Offshore Technology Conference . 10.4043/4556-MS . 978-1-61399-075-9.
5. New Ram Tensioner Aids Underwater Lifting Operations . de Laval, Nancy . Summer 1983 . Faceplate . 14 . 2 . 20–23 . United States Navy . 21 October 2023.
6. Liu, Francis C. . Whaley, Robert C. . Lift System for Salvage Operations . The Military Engineer . Society of American Military Engineers . 78 . 509 . 467–469 . August 1986 .
7. Fly Away Deep Ocean Salvage System (FADOSS) - A Compensated Lift System . Current Practices and New Technology in Ocean Energy . February 1986 . ASME . 11 . 403–409 .
8. Web site: SUPSALV inventory . United States Navy . 27 June 2023.
9. Helicopter Recovery in Somalia . Cooper, Keith R. . March–April 1994 . Naval Aviation News . 20–21 . 21 October 2023.
10. News: 20,000 Pounds of Tension . Tyson, Peter . July 8, 1998 . NOVA: Into the Abyss . PBS Online . 21 October 2023.
11. Navy Goes to Great Depths to Determine Cause of Air Force Crash . Thompson, Mark . January 10, 2013 . Time . 16 August 2023.
12. News: Navy Recovers C-2A from Fatal 2017 Crash from 3 Miles Underwater . LaGrone, Sam . June 5, 2019 . USNI News . United States Naval Institute . 27 June 2023.
13. News: Navy Recovers Lost Aircraft From Three Miles Below the Ocean's Surface . Mizokami, Kyle . June 7, 2019 . Popular Mechanics . 27 June 2023.
14. News: Team concludes recovery operations of Stalker 22 in the Mediterranean Sea . Sukhdeo, Marcello . June 3, 2020 . Vanguard Canada . 16 August 2023.
15. News: U.S. Navy Recovers MH-60S Helicopter from Record Depth . March 22, 2021 . Naval Sea Systems Command . 27 June 2023.
16. Record Breaking Deep Ocean Salvage Operations . Heinrich, Mark . LeHardy, Peter K. . 10.23919/OCEANS44145.2021.9705732 . September 20–23, 2021 . OCEANS 2021 . San Diego, California.
17. News: The Navy Recovered This Sunken Seahawk Helicopter From Three-And-A-Half Miles Below The Sea . Newdick, Thomas . March 23, 2021 . The Drive . 27 June 2023.
18. Operation Lightning Salvage: F-35C Salvage in the South China Sea . LCDR Neil "Spanky" . Tublin . November 2022 . Faceplate . United States Navy . 27 June 2023 . 11.
19. News: UPDATED: Navy Recovers Crashed F-35C From Depths of South China Sea . LaGrone, Sam . March 3, 2022 . USNI News . 16 August 2023.
20. News: Navy salvage system is in St. John's and preparing for mobilization, Navy official says . Liebermann, Oren . June 21, 2023 . CNN . 16 August 2023 . The FADOSS was most recently used to recover a F/A-18 Super Hornet fighter jet from the Mediterranean Sea last July..
21. News: Navy Recovers F/A-18E Super Hornet Blown off Deck of USS Harry S. Truman . LaGrone, Sam . August 8, 2022 . USNI News . 16 August 2023.
22. News: US Navy recovers jet blown off aircraft carrier from bottom of ocean . Kaufman, Ellie . August 8, 2022 . CNN . 16 August 2023.