Twin Disc for new class of SEACOR Fast Supply Vessels

The FSV Alya McCall is fitted with five Cummins engines for a total power of 13,500 hp

APRIL 21, 2016—Delivered last year by Gulf Craft, one of SEACOR Marine’s newest Fast Supply Vessels, 13,500 hp Alya McCall, relies on five high-performance Twin Disc MGX-61500SC QuickShift transmissions to provide the crucial links between the ship’s five powerful Cummins engines and Hamilton Waterjets.

Gulf Craft recently delivered the Najla McCall (photo inset below), the sister to the Alya McCall and second in the SEACOR Marine—Express Plus class.

The 206 ft x 32 ft Marshall Islands-flagged Alya McCall will accommodate 16 crew, 100 passengers and 300 long tons of deck cargo. The aluminum FiFi-I class vessel has dual FFS pumps and remote-controlled monitors. Its five Cummins QSK60 Tier 3-compliant engines each deliver 2,680 bhp at 1,900 rev/min. Paired 

with Twin Disc transmissions and five Hamilton HT-810 Waterjets, the combination achieves a top speed of 38 knots. The Alya McCall is currently in service in the Persian Gulf.

The Alya McCall’s station-keeping capability is provided through the combination of three Thrustmaster 30TT200 electric-mechanical tunnel thrusters supplied by Thrustmaster of Texas in working in conjunction with the azimuth-like waterjets, all of which are controlled by a Kongsberg DP-2 dynamic positioning system.

Designed by IncatCrowther and built by Gulf Craft, Franklin, LA, the Alya McCall is is certified by the USCG under the provisions of 46 CFR Subchapter T and by the American Bureau of Shipping as a High-Speed Craft with DP-2 and Fire-Fighting Capability notations. It is classed as ABS +A1, HSC Crewboat, Restricted Service, OE, Fire Fighting Capability, +AMS +DPS2.

Provided by Twin Disc distributor Sewart Supply, Morgan City, LA, the MGX-61500SC transmissions feature QuickShift technology. They instantly deliver smooth, seamless torque to the waterjets, from neutral to full ahead. And while waterjets rely on deflectors for reverse thrust, the shaft rotation can be reversed to backflush an intake screen if debris blocks its flow.