WLBB-30 Mackinaw Great Lakes Icebreaking (GLIB)
| Displacement (LT) | 3,500 |
| Length | 240 feet |
| Beam | 58.5 feet |
| Draft | 16 feet |
| Buoy Deck Area | 3133 sq. ft |
| Machinery Arrangement | AC-AC Diesel-Electric |
| Main Engines | 3 x 4200 HP, Diesel Generator |
| Propulsors | 2 x 3350 kW, Azimuthing Propulsion |
| Maximum Speed | 15 knots |
| Crane | 20 ton hydraulic 60 ft boom |
| Machinery Plant | Integrated Ship Control System including Plant Control & Monitoring and Dynamic Positioning |
| Main Propulsion | Integrated main propulsion & electric plant |
| Auxiliary / Emergency Generator | 715 kw |
| Propellers | ABB Azipod® - Fixed pitch, 10 ft diameter |
| Level Ice Capability (ahead) @ 3 knots | 32 inches |
| Level Ice Capability (astern) @ 2 knots | 32 inches |
| Refrozen Brash Ice Capability (ramming) | Up to 10 feet |
| Ridge Ice Capability (penetrate in < four rams) | 10 feet within 30 minutes |
| Law Enforcement | (2) Medium size Machine Guns and various Small Arms |
| Aids to Navigation | Yes |
| Oil Spill Control | VOSS |
| Fuel Oil Capacity | 130,896 gallons |
| Shaft Horsepower (shp) | Rated: 9,119 (3.4MW/pod) Bollard: 211 RPM Power: 4,460 hp (3.33 MW/pod) |
| Fresh Water Capacity (gallons) | >27,500 (10 days for 50 man crew using 50 gpd |
| Maximum Range | 4,000 NM @ 12 kts 9,000 NM @ 9 kts |
| Stopping Distance | < 1,000 feet |
| Circumnavigate Beset 1000' Vessel in Heavy Ice (32" solid level) |
Yes - within 12 minutes |
| Sewage Treatment, Trash, & Hazmat Storage | Hold for 10 days (based on 50 person crew) All grey water, all black water, trash compactor Retails all trashes and separate: glass, plastics, & paper Retail all HAZMATs |
| Crew Size |
Nine Officers |
| Support | Outside contractors and USCG |
| Mixed Gender Accommodations | Two person staterooms |
USCGC MACKINAW (WLBB-30) is designed to meet or exceed the following icebreaking characteristics:
| Continuous Mode |
3 knots ahead in 32" solid level ice
10 knots ahead in 14" solid level ice |
|---|---|
|
2 knots astern in 30" solid level ice |
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3 knots ahead and 2 knots astern in 8' brash ice |
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| Ramming Mode | Average .5 knots ahead, backing and ramming in 42" solid level ice |
| Average 0.5 knots ahead, backing and ramming in 5' refrozen brash ice | |
| Average 0.5 knots ahead, backing and ramming a 12' pressure ridge | |
| Fully penetrate a 10' pressure ridge in 4 rams or less within 30 minutes | |
| Escort Vessels and Free Beset Vessels | Cast in a 300' wide channel with a depth of 21' |
| Back from existing track in 30" solid level ice and 12' brash ice | |
| Circumnavigate a beset 1000' Laker within 12 minutes in 32" solid level ice | |
| Flush 32" solid level ice and 12' brash ice from beset vessels and fixed structures | |
| Clear ice jams by flushing and ramming | |
| Maneuverability | Turn 180 degrees in a 300' wide 21' deep channel in 5 minutes in 32" solid level ice and 12' brash ice |
| Turn 360 in her own length in 24" solid level ice | |
| Break out of track channel and turn 90 degrees within 30 seconds in 32" solid level ice | |
| Arrive and depart a standard berth in 32" solid level ice and 12' brash ice | |
| Extract herself from a stopped position at the end of rams under her own power |
A comparison of the two icebreakers.
| New (WLBB-30) | Old (WAGB-83) | |
|---|---|---|
| Level Ice Capability (ahead) @ 3 kts | 32" (Model test estimates ship will do 6.4 kts when at 15.5' draft and 9.1 kts in 24" of ice) | 36" |
| Level Ice Capability (astern) @ 2 kts | 32" (Model test data suggests 4.4 kts when at 15.5' draft, 4.6 kts at 16.0' draft, and 6.2 kts in 24" of ice) | |
| Refrozen Brash Ice Capability (ramming | Up to 10' | > 60" |
| Ridge Ice Capability (penetrate in < 4 rams) | 10' within 30 min | 12-15' |
| Law Enforcement | (2) Medium Size Machine Guns and Various Small Arms | Small Arms |
| Aids-to-Navigation | Yes (Same as WLB) | None |
| Oil Spill Control | VOSS | None |
| Fuel Oil Capacity (gal) | 130,896 | 276,000 |
| Shaft Horsepower (shp) | Rated: 9,119 (3.4 MW/pod) Bollard: 211 RPM Power: 4,460 hp (3.33 MW/pod) | 10,000 |
| Fresh Water Capacity (gal) | >27,500 (10 days for 50 man crew using 50 gpd) | 22,000 Useable (7 days for 75 crew) |
| Maximum Range | 4,000 NM @ 12 kts 9000 NM @ 9 kts predicted | 41,000 NM @ 11.5 kts |
| Stopping Distance | < 1000' | Crash stop 1,000' |
| Circumnavigate Beset 1000' Vessel in Heavy Ice (32" solid level) | Yes-within 12 minutes | Yes-30 minutes |
| Sewage Treatment, Trash & Hazmat Storage | Hold for 10 days (base on 50 person crew): All Grey Water All Black Water Trash Compactor, Retails all trashes and separate: glass, plastics, & paper Retail all HAZMATS | Hold for grey and black water for 4 days. Garbage 7 days. Hold waste oil after separating water. |
