International Dry-Dock Conference
Heger Presentation
The first part focused on the salvage of the Machinist, which had been sunk by a typhoon in Apra Harbor, Guam. Heger was commissioned to
December 14, 2025
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The International Dry-Dock Conference (IDDC) is a globally recognized event providing advanced technical training for professionals across the dry-dock and drydocking industry. Participants include representatives
from shipyards, government agencies, engineering and consulting firms, maritime organizations, and vessel operators — with attendees spanning six continents.
This conference series has become one of the world’s most respected platforms for collaboration and knowledge exchange. It brings together hundreds of practitioners, researchers, and specialists who are shaping the future of dry-docking operations, engineering, and safety.
The papers and presentations featured at the event cover a wide spectrum of topics, addressing both long-standing challenges and emerging issues within the dry-dock community. As technology continues to evolve, new materials and methods — such as rubber and composite blocking systems — are being introduced as alternatives to traditional wooden supports. These innovations bring both opportunities and complexities, all of which are explored through expert-led presentations, case studies, and technical discussions.
The IDDC serves as a critical venue for understanding how modern tools, materials, and engineering practices are being implemented across the industry, and for examining the challenges encountered during their adoption.
At the International Dry Dock Conference in Houston, Texas (May 2017), Robert Heger presented a detailed technical overview of the Machinist AFDB‑8 floating dry-dock — a massive and complex marine structure with the following principal specifications:
Length Overall: 833 ft
Width Overall: 176 ft
Pontoon Deck Length: 772 ft
Clear Interior Width: 144 ft
Depth of Pontoon at Center Line: 17.7 ft
Total Depth to Top of Deck: 68.7 ft
Design Capacity: 30,000 LT buoyant
Capacity per Foot: 55 LT/FT
These dimensions highlight the engineering sophistication required to operate and maintain a floating dry-dock of this scale.
Robert Heger, President and Chief Engineer of Heger Dry Dock, Inc., is a pioneer in floating dry-dock design, inspection, and operational safety. He provides consultation on all types of dry-docking challenges and serves as the principal lecturer for Dockmaster’s Training Seminars, which train dockmasters, naval architects, and marine engineers in the fundamentals of safe ship docking.
A typhoon in Apra Harbor, Guam caused the sinking of the Machinist. Heger was tasked with refloating the dry-dock, executing a highly technical operation involving:
Closure of hull apertures
Dewatering of pontoons and wing walls
Integration of hydrostatic drafts and deflection data
Monitoring water temperature and environmental conditions
Engineering precise ballast calculations
Applying docking control principles to maintain stability
This salvage effort required exceptional precision and coordination.
After salvage, the dry-dock required renovation to increase lift capacity and meet NAVSEA 1625‑D certification requirements. Renovation was planned in China, but the dry-dock could not be safely towed or loaded onto a heavy-lift ship due to its length.
Heger developed an innovative solution: Cut the dry-dock into two sections while afloat, then load both sections onto a single heavy-lift vessel with their longitudinal axes rotated 90 degrees relative to the ship.
Key engineering considerations included:
Selecting a separation point near amidships
Adjusting ballast before and during cutting
Maintaining stability and deflection control throughout the operation
Weight surveys and draft readings
Displacement calculations
Deflection measurements
Weather and water temperature assessments
Installation of shear beams and gap monitors
Temporary ballast system setup
Watertight conversion of exposed bulkheads
Longitudinal members
Pontoon sides
Deck
Bottom plate
Wing walls
Safety deck
Mid deck
Final wing shell separation
No movement was detected during separation — confirming the precision of the ballast and structural controls.
Heger’s work established a safe, repeatable method for sectioning floating dry-docks. His team:
Integrated docking principles into production cutting
Developed a six-step cutting plan
Conducted weight surveys and deflection monitoring
Used temporary pumps, gap readers, shear beams, and wire ropes
Maintained continuous oversight of drafts, gaps, deflection, and weather
The project was completed safely, with both sections perfectly ballasted and ready for transport.
The Machinist AFDB‑8 case study demonstrates one of the most complex floating dry-dock salvage and renovation operations ever undertaken. Robert Heger’s work combined hydrostatics, structural analysis, ballast control, and innovative engineering to safely refloat, section, and transport a massive dry-dock that could not otherwise be moved. His method established a reliable process for cutting floating dry-docks while afloat, ensuring stability through precise monitoring and control. The project stands as a benchmark example of advanced dry-docking problem‑solving and industry innovation.
This paper was presented at the International Dry Dock Conference (IDDC) 2017 by Newport News Shipbuilding:
Dock Master: John Anderson
Naval Architect: AJ Bierbauer
Their presentation focused on modernizing the undocking process for aircraft carriers that remain in dry dock for extended maintenance periods.
Newport News Shipbuilding identified major limitations in its traditional undocking method. The previous process relied on:
Daily manual reporting of weights added or removed
Estimated percentages of work completion
Authorized drawings that were often unavailable or outdated
Work package tracking that did not always match official documentation
Frequent inaccuracies in weight reporting from ship’s force and trades
This created uncertainty in weight management and made it difficult to maintain accurate balance during undocking.
The legacy method introduced operational and safety risks:
Side-to-side balance (list) could not be corrected during flooding.
Undocking continued without pausing to verify or adjust list.
Manual weight reporting was unreliable and labor-intensive.
These issues increased risk during the most critical phases of undocking.
To improve safety and accuracy, Newport News Shipbuilding implemented a revised undocking process developed by the dock master and naval architects. Key changes included:
Elimination of daily weight reporting
Removal of ballast control requirements
Use of historical data as the baseline for undocking calculations
This new method allowed real-time list adjustments while the dry dock was flooded, significantly improving control.
The updated undocking process incorporated several technical improvements:
Calibrated micrometer levels and transits measured the ship’s list with high precision.
Transporters with test weights were positioned on the flight deck to adjust list and trim.
During undocking, when the water level reached 28 feet, the operation slowed or paused.
This pause allowed micrometers to stabilize and provide accurate list readings.
These steps ensured continuous monitoring and correction of the carrier’s balance.
The improved undocking process delivered significant advantages:
Reduced labor by eliminating manual weight reporting
Resolved a critical safety issue related to uncontrolled list
Enabled real-time list adjustments during flooding
Improved accuracy in weight and balance management
Enhanced dock master control throughout undocking
Overall, the new method increased both safety and efficiency.
The procedural improvements at Newport News Shipbuilding represent a major advancement in carrier undocking operations. By removing unreliable manual reporting and introducing precise measurement tools, the dock master gained the ability to monitor and adjust list dynamically. This innovation reduced labor hours, improved accuracy, and strengthened safety during one of the most complex phases of dry-docking.
Newport News Shipbuilding modernized its carrier undocking process by eliminating manual weight reporting, using historical data, and introducing precise list‑measurement tools. These improvements allowed real-time list adjustments during flooding, greatly enhancing safety, accuracy, and operational efficiency.
Presented by Bay Ship & Yacht Shipyard, Glen Roberts, Naval Architect
HMB‑1, designed by Glen Roberts, is a submersible barge originally created for the AZORIAN Project, supporting the Glomar Explorer in the recovery of the sunken Russian submarine K‑129. The barge features:
Length Overall: 324 ft (99 m)
Beam: 106 ft 8 in (32.5 m)
Hull Depth: 19 ft (5.8 m)
Light Displacement: 5,800 LT
Total Displacement: 6,290 LT
Well Width: 76 ft 8 in (23 m)
These dimensions reflect the barge’s unique role as a submersible platform capable of supporting highly specialized operations.
Following its original mission, the Sea Shadow—a 164‑ft experimental stealth ship—was constructed inside HMB‑1. The Sea Shadow itself measured:
Length: 164 ft
Beam: 68 ft
Draft: 15 ft
Displacement: 563 LT
Government contractors made extensive modifications to HMB‑1 to support the construction of the Sea Shadow.
Later, Bay Ship & Yacht purchased HMB‑1, demolished the Sea Shadow, and performed a comprehensive overhaul of the barge. Upgrades included:
Structural improvements
Mechanical system upgrades
Sandblasting and painting
System modernization
These modifications were necessary to achieve certification for dry-docking vessels.
HMB‑1 was further modified to meet Bay Ship & Yacht’s need to dock larger vessels. Key features include:
Larger beam
Increased lift capacity
Taller wing walls
Retractable roof
Gantry crane
These enhancements allow the barge to accommodate and service significantly larger ships.
HMB‑1 is equipped with advanced systems, including:
Ballast Air Supply and Breakout System
Constant Pressure Air Supply and Overpressure Protection System
Hydraulic System
Wet Lock System
Control Space Pressurizing, Venting, and Atmospheric Reference System
The automated control systems manage:
Ballast and tank flooding
Power and winch operations
Hydraulic and seawater cooling systems
Electrical distribution and monitoring
The Hughes mining barge was ultimately transformed into a floating, covered dry dock with a sophisticated automated control system.
To ensure safe operation, structural and lifting capacity estimates were performed, including a transverse strength analysis following ABS guidelines.
HMB‑1 achieved USCG SFLC 8634 certification, which required:
Underwater survey
Visual inspection of tanks
Review and approval of engineering reports by a Professional Engineer (P.E.)
This certification confirmed HMB‑1’s readiness for commercial dry-docking operations.
HMB‑1, originally built for the AZORIAN Project, was transformed by Bay Ship & Yacht into a modern floating dry dock capable of servicing large vessels. Extensive structural upgrades, advanced automation systems, and USCG certification enabled the barge to operate as a fully functional, covered dry-docking platform.
Presented at the International Dry Dock Conference (IDDC) 2017) Presenter: Moses Finale, Dry Dock Program Manager, Norfolk Naval Shipyard
This presentation detailed the complex dry-docking and conversion operations performed on the USS LA JOLLA (SSN‑701), a 688‑class submarine transformed into a next‑generation Modular Training Ship (MTS).
To prepare the submarine for docking, 20 tons of weight were removed to allow the LA JOLLA to float higher within the dry dock. Once the sea level was reached, the caisson was reinstalled and the dry dock was super‑flooded.
Flooding continued until the water level rose three feet above the river level, enabling the submarine to breach over the strongbacks. This innovative maneuver ensured safe entry and precise positioning inside the dock despite depth limitations.
During the conversion phase, the strongback system played a critical role by enabling Self‑Propelled Modular Transporters (SPMTs) to operate efficiently within the dock basin.
This allowed:
Smooth relocation of hull cuts to fabrication containments
Controlled movement of large structural sections
Seamless installation of new submarine modules
The strongback‑SPMT integration significantly improved workflow and precision during the conversion.
Docking a 688‑class submarine in a dry dock shallower than the vessel’s draft presented significant challenges. Dry Dock #3 at Norfolk Naval Shipyard is 27 feet deep, while the LA JOLLA drafts 30 feet, with the rudder extending two feet below the base. The solution involved removing all possible liquid and static weight (20 tons) while maintaining stability. Super‑flooding the dry dock allowed the submarine to clear the strongbacks and breast over them safely, demonstrating the skill and coordination of the Norfolk team.
I have personal experience dry‑docking the LA JOLLA in Dry Dock #2A at Pearl Harbor, as well as another 688‑class submarine in Dry Dock #3, both to a depth of 25 feet, using the BAM’S system. These operations required precise hydrostatic control, careful weight management, and close coordination — reinforcing the complexity of docking 688‑class submarines in depth‑limited dry docks.
The Modular Nuclear Training Ship (MTS) represents the next generation of naval training platforms. The converted LA JOLLA is used to:
Qualify new nuclear operators
Train and advance naval personnel
Support long‑term fleet readiness
The MTS program ensures that future nuclear operators receive hands‑on, realistic training in a controlled environment.
The USS LA JOLLA conversion required innovative dry-docking techniques, including weight reduction and super‑flooding, to safely maneuver a submarine deeper than the dry dock itself. Strongbacks and SPMTs enabled efficient movement of hull sections, while the final MTS platform now serves as a critical training asset for the U.S. Navy.
Presenter: Ted Williams, President, SENESCO Marine (New Construction & Full‑Service Shipyard)
The successful implementation of the Ships for America Maritime Action Plan depends on:
Effective execution across shipyards and maritime agencies
Bipartisan support in Congress
Alignment with President Trump’s Executive Order on Restoring America’s Maritime Dominance (April 9, 2025)
The presenter emphasized that understanding America’s maritime past — and its current challenges — is essential to recognizing why this action plan became necessary.
Between 1941 and 1945, the United States led the world in shipbuilding, producing 94,179 ships, including:
30 aircraft carriers
10 battleships
13 heavy cruisers
34 light cruisers
882 destroyers
217 submarines
84,198 landing craft
Numerous auxiliary and support vessels
This era represented the height of American maritime industrial capability.
Today, the presenter noted several critical issues:
The U.S. produces 0.1% of global shipbuilding output
China produces 53.3%, more than the rest of the world combined
The U.S. has 8 major shipyards employing 78,000 shipbuilders
China has 7 major shipyards employing 280,000 workers
These disparities highlight the urgency of revitalizing America’s maritime industrial base.
Key components of the plan include:
Maritime Prosperity Zones to stimulate regional investment
Workforce development initiatives to expand skilled labor
Maritime Security Trust Fund to provide sustained financial support
These measures aim to rebuild shipyard capacity, strengthen the maritime workforce, and modernize infrastructure.
According to the presenter, Executive Order 14269 outlines a national mission to restore maritime dominance and support economic and national security goals. The order includes:
Funding for small shipyards
Tax incentives for shipyard modernization
Creation of Maritime Investment Zones
Workforce development programs
Establishment of a Maritime Security Trust Fund
These initiatives are intended to provide long‑term stability and growth for the maritime sector.
The presenter identified several major challenges facing the U.S. maritime industry:
Insufficient number of shipyards
Limited skilled workforce
Historically inadequate funding for shipyards, especially small facilities
Outdated dry docks requiring modernization
Shortages of materials needed for docking and ship repair
The presentation highlighted serious concerns about the long‑term decline of America’s shipbuilding industry, including shipyard closures and the loss of skilled maritime labor. However, the presenter expressed optimism that Executive Order 14269 (American Maritime Recovery Act) provides a renewed opportunity to rebuild the sector.
The plan includes:
Rebuilding shipyards
Expanding the maritime workforce
Modernizing ports and dry docks
Establishing funding through grants, tax credits, investment zones, and trust funds
The presenter emphasized that now is the time for shipyards, maritime companies, and policymakers to take advantage of these opportunities.
The Ships for America Maritime Action Plan aims to rebuild U.S. maritime strength through investment zones, workforce development, shipyard modernization, and sustained funding. Supported by Executive Order 14269, the plan seeks to reverse decades of decline and restore America’s maritime industrial capability.
The VB‑10,000 is a heavy‑lift, twin‑gantry catamaran consisting of two massive truss space frames mounted on two independent barges. Each truss tower rises 240 feet, with a 178‑foot hook height, enabling the vessel to perform ultra‑heavy offshore lifts and decommissioning operations.
Barge Specifications:
Dimensions: 290 ft × 72 ft × 20 ft (each barge)
Draft (unloaded): ~12 ft
Weight: 6,000 long tons per barge
Load per foot: ~29 LT/ft
Thrusters: Four drop‑down azimuth thrusters per barge
Dynamic Positioning: Fully integrated DP system
Motion System: Spindle system allowing two rotational degrees of freedom (port/starboard and fore/aft)
Trim & Height Control: Up to 30 ft of trim variation and 30 ft baseline height adjustment
This unique configuration makes the VB‑10,000 one of the most complex vessels ever dry‑docked in a U.S. shipyard.
The owner‑furnished docking plan allowed only one barge to be lifted at a time, leaving the second barge waterborne. This imposed:
Significant operational constraints
Increased total docking time
Higher risk during transitions
Reduced efficiency for maintenance and inspection
This limitation required a new, innovative docking strategy to safely and efficiently handle the vessel.
Capacity: 12,000 LT
Keel Length: 383 ft
Width: 90 ft
Keel Load Capacity: 38 LT/ft
Gripper System: Five grippers with pinned flaps
Dock Mobility: ~6 inches in any direction for dredging or ship‑to‑ship transfers
Capacity: 46,440 LT
Keel Length: 787 ft
Width: 164 ft
Keel Load Capacity: 63.5 LT/ft
Gripper System:
Two grippers perpendicular to T‑rails
One gripper at 45 degrees
These facilities provided the necessary lift capacity and structural support for a simultaneous dual‑barge docking.
Dock Master Kurt Cramer engineered a method to dry‑dock both barges simultaneously, cutting the total docking time in half compared to the original sequential plan.
This approach required:
Re‑evaluation of block arrangements
Structural load analysis for twin‑hull landing
Gantry clearance verification
Dynamic positioning coordination
Real‑time laser alignment
The result was a safe, efficient, and resource‑optimized docking operation.
Upon arrival from sea:
Dockside tractors (“mules”) and stern lines secured the vessel
Tugboats were released once the rig was fastened
Harbor pilots departed with the tugs
The VB‑10,000 was prepared for controlled entry into the dry dock
Laser alignment tools were used to verify the starboard barge’s position along the north side of the dock.
Key steps:
Stern reference points established on both dock sides
Starboard barge landed first
Raised by one foot and secured
Rig movement prevented before port barge entry
The catamaran had to span Pier H between two repair platforms
A crane at the river end was inoperative, leaving 43 ft of clearance between the crane boom and VB‑10,000 arch
War Eagle’s wing walls had tilted outward over time; new walls were built to match the angle
A temporary pause was required due to bracket jamming on the spud rail of Dry Dock Alabama
Port barge trim difference: stern 1.5 ft lower than bow
Laser devices verified starboard barge alignment
Reference marks placed at stern of both sides of Dry Dock Alabama
Starboard barge entered on an even keel, offset 7 ft 6 in to port
Offset approved by Heger Dry Dock structural engineers
During block inspection:
Several blocks were not making contact
The first two forward side blocks showed no contact
Adjustments were required to ensure proper load transfer
Dock Master Kurt Cramer demonstrated exceptional innovation and technical expertise by developing a method to dry‑dock the VB‑10,000 using existing Alabama Shipyard resources. His simultaneous dual‑barge docking strategy:
Reduced total docking time by 50%
Improved operational efficiency
Maintained structural safety margins
Earned commendation from project stakeholders
This Tag stands as a significant contribution to the International Dry-Dock Conference archive, showcasing advanced problem‑solving in modern heavy‑lift vessel dry‑docking.
The first part focused on the salvage of the Machinist, which had been sunk by a typhoon in Apra Harbor, Guam. Heger was commissioned to
Newport News Shipbuilding recognized the necessity to enhance their existing undocking procedures for aircraft carriers that remained in dry dock for extended periods.
The USS LA JOLLA (SSN-701) underwent a significant transformation at Norfolk Naval Shipyard, where it was converted into a Modular Nuclear Training Ship (MTSs). The
HMB-1 was modified to meet the company’s need to dock larger vessels.
The successful implementation of the Ships for America Maritime Action Plan depends on effective execution, bipartisan support in Congress, and alignment with President Trump’s Executive