Update on Nacra Recall and Bearing Replacement Plan
Nacra Sailing principals had a call with Nacra 17 Class President, Marcus Spillane, and Class Manager, Ben Remocker on Sunday morning. Here is the latest information.
New Replacement Bearing
The replacement design has been completed. The first prototype will be built on Monday.
The prototype will be fitted to a boat to ensure it physically works and that it fits properly. The prototype is an adaptation of an existing design for high performance catamarans so no problems are expected. With a moving part, however, it must, and will, be checked.
The prototype will then be fitted to the test jig. Working load and breaking strength tests will be performed. This to ensure the larger, load-bearing, surface solves the crushing problems that have been occurring.
Assuming both of these tests confirm the prototype as a solution, production will begin on Wednesday. The production facility has set aside their complete machining capability for the parts to be built at a rate of at least 15 sets per day.
As of Sunday afternoon there are 35 teams registered for the World Championships. It seems realistic to supply each team competing at the Worlds with replacement bearings by the end of this week in a best-case scenario.
The bearing replacement procedure is simple. Each lower bearing is held in by 4 “allen key” screws. Teams will be able to change the bearing themselves.
Availability of Boards for Competing Teams
Some questions have been asked about the suitability of the boards exposed to the high point loading of the original bearing, and specifically whether these boards can continue to be used.
The initial assessment by Nacra Sailing is that the mode of failure of the boards is via a crushing of the board first, followed by shearing of the material after it loses its shape. As such, any boards without crushing should be ok.
Morrelli & Melvin, the designers of the boards, will continue to investigate this question and have been asked to produce an opinion on the matter.
At the World Championships Nacra Sailing will endeavor to have an ultrasonic testing machine to evaluate boards for structural damage before the regatta. This non-destructive testing technique should allow teams to have confidence, or not as the case may be, in their boards that have been exposed to sailing with the original bearing. Most of these boards are scheduled to be replaced anyway.
2017 Worlds
We discussed all options regarding the World Championships. We looked at cancellation, delay and holding the event as scheduled. All parties are working toward being able to hold the World Championship, as scheduled, in 3 weeks’ time. The Nacra 17 Executive Committee will have a meeting on Wednesday to review everything at that point. We will update the Class at that time.
