Te Laa o Lata of Taumako: Gauging the performance of an ancient Polynesian sail

Voyaging canoes were the vehicles of ancient Pacific exploration, settlement and interactions. However, we know little about the ocean-going performance of those vessels. This account of Taumako (Duff Islands) voyaging technology draws on 20 years of collaborative research initiated by Koloso Kaveia, the late paramount chief of Taumako, during which a new generation learned to build and sail voyaging canoes using only ancient materials, methods, designs and tool types. Recent researchers have tested models of bifurcate tipped sail shapes in wind tunnels. The shapes they used, which appear similar to what Taumakoans call Te Laa o Lata, demonstrated outstanding efficiency compared to others. But one researcher noticed that a more flexibly tipped model performed better than a rigid model. Historical, cultural, technical and operational information about the proportions and the built-in flexibility and plasticity of the design, materials and rig of real Te Laa o Lata suggest that there is much more to learn about their performance. If a model of Te Laa o Lata is to be tested in a wind tunnel it must be shape-shifting and proportionally correct. It also should be rigged to allow it to align and adjust itself in the ways that it actually does at sea. Furthermore, the role of the mostly submarine hull and buoyant outrigger on sail and vessel performance should be measured in a tow tank. But since Taumakoans are still building and sailing Vaka o Lata (ancient Polynesian voyaging vessels) using centuries-old designs, materials and methods, it is still possible to measure the aerodynamic performance of Te Laa o Lata and the hydrodynamic performance of the overall vessel at sea, as well as to more fully understand how the vessel works and how it is sailed under various conditions and for various purposes.