They don't -need- to be. There are commercial options (see: https://www.ge.com/renewableenergy/wind-energy/onshore-wind/cypress-platform https://www.ge.com/rene

They don't -need- to be. There are commercial options (see: https://www.ge.com/renewableenergy/wind-energy/onshore-wind/cypress-platform https://www.ge.com/renewableenergy/wind-energy/onshore-wind/... for example) with segmented blades. However, I understand that doing a composite/chemical joint basically involves setting up a mini-factory, since your joint quality will depend very much on being able to control the conditions. Mechanical joints require less on site infrastructure, but have an efficiency penalty (https://www.nrel.gov/docs/fy23osti/84397.pdf https://www.nrel.gov/docs/fy23osti/84397.pdf). In any case, I imagine Radia is betting on getting enough volume to make the development cost irrelevant. In the end, you had to transport the roughly the same amount of material onsite anyways, in roughly the same form factor. The cost of a fleet of aircraft can be amortized over a huge geographic span wind farms, while also being attractive from the perspective of delivering replacements. I definitely think segmented blades are a way forward, but I can also see Radia's argument. I can totally believe that the "real winner" is going to a combination of situation and execution.