How to Create Sheet metal loft with guide curve?

We have to create a sheet metal part for the arch profile (See the attached JPG).

I tried to create loft in sheet metal but it is not having the guide curve option.

I also tried to convert the loft feature to sheet metal but it is not converting as there is no linear edge.

I want to convert the arch profile (Solid model) to sheet metal for getting the flattend view.

Please help.

Thanks,

Arun

SolidworksSheet Metal