“Sea Fighter” in Coast Guard colors
Thought perhaps this study might be of interest, and did not want to loose the link to the study. Some of the conclusions seem to bear on any discussion of the important characteristics of Coast Guard cutters, particularly as our Maritime Domain Awareness improves.
Characteristics such as speed, crew size, deployable surface and air assets, and requirements for a reconfigurable mission bay would influence the design of any possible future Cutter X. In terms of deployable air assets, it is likely a helicopter/UAS combination would be preferable to the two helicopters considered here, and would make it easier to provide hangar space.
Any requirement for extremely high speed requires careful consideration of the attendant consequences, as we have seen in the LCS program, but we have known how to reliably get speeds up to 33 knots for decades.
I have provided the Executive Summary below.
(Thanks to Lee for bringing this to my attention.)
The U.S. Coast Guard (CG) Research and Development Center (R&DC) evaluated the U.S. Navy’s Sea Fighter vessel for potential applicability to CG missions. When compared to other CG cutters, Sea Fighter has four unique capabilities/characteristics that could significantly impact CG mission effectiveness:
- High-speed (50 kts)
- Multiple deployable surface and air assets (three 11m Rigid Hull Inflatable Boats (RHIBs) (Cutter Boats Over-The-Horizon (CB-OTH)) or five 7m RHIBs (Short Range Prosecutors (SRP)), two HH-60s or two HH-65s, and multiple Vertical Unmanned Aerial Vehicles (VUAVs))
- Small crew size (26 persons)
- Reconfigurable Mission bay (accommodates 12 mission modules)
This project evaluated Sea Fighter’s unique capabilities through a combination of engagement modeling and simulation, human systems integration modeling, and Sea Fighter crew and shiprider insights (following multiple R&DC operational test and evaluation exercises).
High-speed and multiple deployable assets were evaluated using engagement modeling. Scenarios were developed to simulate fishing-like vessels (lower speed with higher density) and drug smuggling-like vessels (higher speed with lower density). The results of the analysis showed that by themselves high-speed and multiple deployable assets made little improvement in mission effectiveness. However, as Sea Fighter’s sensor detection range and/or its off-board detection capability (a vital contributor to maritime domain awareness (MDA)) improved, highspeed and multiple deployable assets did lead to significant improvements in mission effectiveness. In the simulated scenarios, improving components of MDA (off-board detection capability) was the critical performance driver, followed closely by increasing intercept speed (from 30 to 50 kts) and increasing the number of deployable assets from two to four (particularly increasing the number of deployable helicopters). These improvements result in an almost 30 percent increase in the number of high-speed targets that can be boarded.
Crew size, required functions, and fatigue associated with a typical CG patrol were evaluated through human system integration (HSI) modeling. With Sea Fighter’s highly automated bridge and engine room, a 26-person crew can sustain many of the required functions. For a typical 14-day patrol, Sea Fighter’s crew could sustain normal Condition-3 watches, multiple boardings (some simultaneously), and multiple VUAV launches. However, HSI modeling showed that Sea Fighter’s crew could not sustain regularly scheduled helicopter flight operations.
To account for these deficiencies, the crew was optimized by adding two boatswain mates and a six-person detachment—Law Enforcement Detachment (LEDET), Maritime Safety and Security Team (MSST), or Maritime Security Response Team (MSRT). This 28+6 optimal crew was able to sustain all required functions. In a typical 14-day patrol scenario, the 28+6 optimal crew averaged three boardings, two helicopter sorties, and three VUAV sorties each day without exceeding acceptable fatigue levels.
Finally, crew and shipriders provided firsthand observations and insights relative to Sea Fighter’s unique capabilities. Some key insights are:
- High-speed capability is a distinct advantage in a vessel accomplishing any law enforcement mission and is especially effective at intercepting fast, evasive, and uncooperative targets.
- Sea Fighter’s ride quality at low speed (less than 15 kts) is very poor and can adversely affect operations or activities; however, ride quality significantly improves at higher speeds (20+kts). The trade off is largely due to hull design consideration made during Sea Fighter’s planning phase.
- RHIB launch and recovery is limited to 5 kts due to the poorly designed stern ramp and vessel movements at low (less than 15 kts) speeds.
- A crew of 26 is too small for typical CG operations.
- Overall, ship layout and configuration are excellent. Bridge layout affords excellent visibility, internal communications, and improved situational awareness with all underway watchstanders located on the bridge. Flight deck lighting, configuration, and manning are exceptional from both a crew and pilot perspective.
- Sea Fighter’s mission bay can provide remarkable mission flexibility, especially for deployable teams such as MSRTs or MSSTs. However, spaces for 12 mission modules seem a bit excessive for CG needs. In addition, the design of the X-Y crane prohibits moving payloads (including extra 11m or 7m RHIBs) while underway.
A 50-kt Sea Fighter-like vessel with four deployable assets (two 11m OTH RHIBs and two HH60 helicopters) can provide significant performance improvement compared to a traditional 30-kt CG vessel (CG High-Endurance Cutter (WHEC) or CG Patrol Boat (WPB)).
A highly automated Sea Fighter-like vessel, with the crew size of a patrol boat, provides more mission capability than a WHEC. The ModCAT hullform and large mission bay provide excellent flexibility for emerging CG missions and demands. Sea Fighter’s speed and multiple deployable asset capability offer outstanding performance improvement potential for the CG; however, a critical enabler is improving detection capabilities – an element of maritime domain awareness. As MDA improves, a 50-kt patrol vessel capable of deploying four assets could provide a tremendous improvement over current and future 30-kt vessels.
The CG needs to continue to evaluate non-standard hull forms such as ModCAT-type vessels for both speed and modularity purposes. High-speed vessels normally have endurance problems based on their fuel consumption rates. This has been one of the perceived shortcomings of this hullform type. However, the ModCAT hullform (i.e. Sea Fighter) provides very good fuel economy and, given the typical patrol profile (12 kt patrol speed, 20 kt transit speed, and 50 kt intercept speed), the vessel is capable of remaining within the patrol area for an entire patrol period. Opportunities exist for the CG to further evaluate other Navy/DOD high-speed vessels (HSV) such as the M88 Stiletto for MSRT type missions and the HSV platforms, HSV Swift and HSV Joint Venture, for extended duration missions.
Additionally, the CG should look at ways to optimize the number and type of deployable and off-board assets through a more detailed M&S analysis. A 50 kt Sea Fighter-like cutter with four deployable assets (e.g., two 11 m OTH RHIBs and two HH-60 helicopters) can provide significant mission performance improvement compared to a standard 30 kt cutter. To maximize the benefit from embarking four deployable assets (two 11 m OTH RHIBs and two HH-60s), a revised approach to boardings would need to be established. Currently, boardings are to be conducted within two hours from the WHEC (at the WHEC’s maximum speed). Under the MSRT CONOPs, the boarding teams would need to be trained similar to MSRTs which are able to defend themselves while conducting a boarding at greater distances from the patrol vessel.
The CG needs to continue to incorporate more automated systems on-board cutters, but have contingency plans (both personnel and equipment) in place for changes in operational requirements or causalities. In order to derive optimal mission effectiveness, the patrol cutter must be able to safely navigate and operate deployable assets in varying sea states and at a reasonable speed. Sea Fighter’s automated systems allow for these evolutions to be conducted with fewer crew members and with an acceptable margin for safety.