I started by finding an old super soaker water gun in my shed with two water tanks. I painted them with black spray paint formulated to work on plastic. After that I painted them with gold spray paint.
I used e-6000 glue to attach them to a small rectangle of mdf board painted flat black. About 1 1/2 inches out from each tank I also glued a length of dowel about the size of a pencil.
Next, I cut wing shapes out of black foam core board. My design involved cutting a base shape and two more pieces to stack on top. I glued these up with wood glue and then painted them with hammered steel spray paint.
I did have to go to the local hardware store for a couple of PVC couplings for use as rocket nozzles. I spray painted them black and them painted them with gunmetal acrylic paint.
When the wings and nozzles were dry, I used e-6000 to glue them to the tanks and the dowels. The dowels make the wings lift away from the base. After the glue dried I used copper rub and buff to distress the tanks.
While the glue was drying, I made some metal patches for the wings using black fun foam and gray metal epoxy. I cut rectangle shapes to fit the wings and used the epoxy to make rivet heads around the edges. When the epoxy dried enough, I painted the patches with black acrylic. When the paint dried I went over the patches with rub and buff and used contact cement to glue them to the wings.
Finally, I used contact cement to attach strips of brown fun foam around the tanks at the top and bottom to simulate leather bands holding the tanks down. At this point, I was done, since this rocket pack was only going to hang from a wall. However, it would not be difficult to attach straps to the mdf board so this could be worn. Any number of extra gears, gauges, wires, etc. could added to make it more complex. The wing design can also be altered to suit any style.
Wall Hanging with Rocket Pack