Revolutionary mast has 3D woven carbon mast track
by Soazig Guého/Sail-World Cruising on 14 May 2012
Safran, high technology international group and a leading equipment provider in the Aerospace, Defense and Security fields, is also a great sponsor of racing yachts where they are able to test new technology.
A new revolutionary mast for Safran Francois Van Malleghem http://www.pixsail.com/
Their latest experiment is in the manufacture of a mast with a 3D woven carbon mast track, giving their eponymous yacht much less weight to carry aloft, making her sturdier yet faster. We can't wait for this to trickle down to the world of the cruising sailor - as it inevitably must, in time.
While the group specializes in the design, manufacturing, and marketing of equipment and systems of high technology mechanical and electronic equipment, this is completely new in the world of sailing. Apparently the weight savings and improvements in terms of performance and reliability are 'huge'.
'This new mast is the result of a lot of different people working together,' explained Guillaume Verdier, the designer and person in charge of the construction of this new 28 metre long spar. 'The real innovation is on its rear side, with a 3D woven carbon track, formed in the same way as Jacquard cloth is produced and which will withstand the strains, unlike a traditional track,' summed up the designer. 'That means we have been able to make weight savings high up and offer improved reliability thanks to this process and to a completely new way of looking at the attachment points.
'This innovative work from the team was only possible thanks to the resources within the Safran Group and Hervé Devaux’s HDS calculation team, who went over my static calculations again and again. What with the calculations and designs, together with the architects that work alongside me, Romaric Neyhousser and Hervé Penfornis, we have spent a lot of time over several months to come up with this innovation.'
The overall philosophy of this new mast was as follows: it had to be lighter, offer better performance, be more reliable and with an overall cost not exceeding 20% more than a classic mast.
Guillaume Verdier explains: 'We didn’t begin with a blank sheet of paper, as the initial choice was to keep the basic arrangement of the first two masts, in other words, it rests on the deck and has three layers of spreaders. We didn’t want to take any risks by completely changing the concept, with for example a mast with two layers of spreaders or a wing-mast, which are both more flexible and subject to dynamic forces.
'We gradually made headway working together: I was involved with the conception and design, Hervé Devaux at HDS checked over my static calculations, Bruno Dambrine at Safran offered us his experience of the 3D woven technology and then, there was also Snecma and Safran Engineering Services (subsidiaries of the Safran Group) working on dynamic calculations.
'Thanks to digital modelling and the means available at Safran, we were able to carry out simulations at each stage of the job concerning the behaviour of the boat and mast, for example, seeing what happens, when she slams into a wave. Thanks to that, we were able to identify strains in certain places that we couldn’t see simply by using static calculations.'
These dynamic calculations, used by Safran in particular for their crash tests, are a new concept in ocean sailing, and enabled the team to advance towards this highly innovative mast. 'We also included the data we already had thanks to the sensors measuring acceleration on board the boat, when she had her previous masts. At each stage, we knew if we were on the right track or if we had things to correct.'
The actual weight savings are obviously confidential. But they are 'huge', according to Jean-Marie de la Porte, Safran’s project manager.
If we are looking at a boat, we need to consider everything, and it is no surprise to anyone that saving weight high up, is something everyone looks for, 'as when you save one unit on top, you can take three times that from the keel bulb, for example,' explained Guillaume Verdier. We end up with a boat that is stiffer, which cuts through the waves more easily, which pitches less, and so is faster.
Returning to the 3D woven technology, this is a process developed in the Safran Group, which involves weaving together carbon threads using the same principle as on a traditional loom.
This technology used in the design of parts for the aircraft industry means that it is possible to obtain mechanical specifications, which are much higher than using traditional carbon.
'The design of this new mast involved calling upon the services of experts within the Safran Group as well as from outside, and this was an extremely enjoyable experience,' stated Jean-Marie de la Porte.
To see the video of the new mast click here