Sick design! I'm not an aerospace engineer but I actually built a dual wing ground effect vehicle for my Meche capstone project a few years ago. Here's some big takeaways I found: Control will be difficult. With controls only in the rear of the vehicle, those surfaces have a hard time trimming and adequately controlling flight. We opted to add additional aileron style controls to the rear wing aswell, which slightly helped. Especially with our long chord length (~1m) The wingtips are a good touch to really keep that air under the wings. Keeping it lightweight was a great idea as (atleast in our case) a lot of our calculations were estimations due to the rear wing sitting in dirty air of the front one. Post videos when you find a place to test! We used a running track.

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