We are not really targeting the private or business jet market (though if someone wanted one for this purpose we wouldn't turn them away!). There is another impressive YC company that is that you should check out, Beyond Aero https://bookface.ycombinator.com/company/26134
We are really targeting a low cost commercial market - moving people and cargo. The smaller size is driven in part by the technology - with 50 seats being a good size to capture a large proportion of flying traffic - and partly that it will be faster and cheaper to certify and get a smaller aircraft into the market.
