Page 46: of Marine News Magazine (July 2014)
ATB Technical Trends
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unfriendly waters. According to Jim Ducker, that?s exactly why NAMJet was chosen. ?Because our system is higher thrust, as opposed to a really high speed unit, we don?t require the precision in the impellor that a high speed unit might need. The RPM on our water jets is almost half of a competitor?s high speed unit. So, we?ve got lower RPM?s that produces less damage, and a much higher impellor clearance rate to the wear ring. This gap allows for certain amounts of sand and grit to pass through with minimum or no damage. It?s those sorts of things that make our pro- pulsion units less susceptible to the conditions that you are talking about. This is not a deep water boat ? it?s made to traverse muddy riverine environments.? Swaying the Army Vote: Advantage NAMJet According to Ducker, when it came time to make its contractor selection, the ?Technical? area was the number one factor. Within that area, reliability was a high consid- eration. And, while the Birdon boat design certainly came into play, ultimately, NAMJet sealed the deal. Ducker ex- plains, ?You can imagine that after 600 hours, there was a lot of wear on all systems, and the NAMJet product really excelled under those conditions. So, the water jet was, we believe, the difference.? Three technical factors were taken into consideration. These included sub factors of (a.) reliability, (b.) conven- tional rafting speed and (c.) forward top speed. Birdon was rated outstanding in technical aspects and only in terms of top speed was the NAMJet beaten. In theatre, howev- er, these boats don?t need to go terri cally fast, but they do need to provide thrust and reliability under load. Jim Ducker added, ?It?s not a slow Jet by any stretch of the imagination, but it?s also not going to be installed in a Pa- trol Boat to try and achieve 40-50 KT.? All competitors were tested with Cummins engines adapt- ed to run on JP8 fuel to drive the jets, identical water con- ditions and other similar variables. Nevertheless, the award was protested by one unsuccessful bidding builder, but the Government Accounting Of ce (GAO) rejected the protest on the grounds that the Birdon boat was technically superior. Commercial Propulsion Equipment, Commercial Applications? In June, we asked if the NAMJet equipped BEB per- formed this well under adverse conditions in a hostile envi- ronment, could it not also perform similar service in niche, commercial workboat applications, as well? Ducker wasn?t ready to commit to such a concept, saying only that his rm would concentrate rst on ful lling the Army contract before considering other applications. But, while water jets aren?t necessarily considered common in inland commer- cial towing and pushboat work, the NAMJet driven Birdon BEB certainly showed its capabilities under dif cult testing circumstances during the Army contract bid phase. Beyond this, and with the newly heightened emphasis on domestic inland infrastructure maintenance, durable shallow draft workboats will certainly be part of that new equation. The recent passage of the long awaited WRRDA bill may well be the catalyst for more such work in the future. Boats em- ploying concepts borrowed from the Army?s BEB might just be the ticket for shallow draft operations. In the meantime, and as NAMJet relocates its manu- facturing facilities to Denver, CO, they will also co-locate with Birdon America in the same 50,000 square foot facil- ity. There, they will jointly build the rst 25 BEB?s in a total contract deal worth $19 million. NAMJet will also continue to provide propulsion for all of its other business within the same building. To that end, Jim Ducker insists, ?Birdon America was established solely for the bridge erec- tion boat. But, Birdon intends to build on NAMJet?s name ? here and internationally. That?s the long term future.? By any yardstick, that?s a pretty good start. PROPULSIONNAMJet?s high-clearance impellers and low-RPM operating range provide exceptional thrust while maintaining top end speed. 46 MNJuly 2014MN July14 Layout 32-49.indd 46MN July14 Layout 32-49.indd 466/18/2014 3:44:42 PM6/18/2014 3:44:42 PM