ah, not cover the plane, but cover the nose.
if you're willing to carve/sand foam:
- stack foam vertically along your horizontal profile, like terraces. make sure you line up the bottom of each foam layer with your profile, not the top. carve them in a bit to get a along the top and bottom to follow how you want the top to slope in.
- Once you've got ones side "terraced", top and bottom, use this and a square strip of flat foam (height = width) and make a template for each layer out of a single piece. drill a pair of small holes for alignment big enough for a pen tip.
- use your template to make two more build pieces (always keep one pattern to cut more).
- on your build pieces, remove the paper from you're new pieces (glues better w/o it and doesn't sand well) pin them together on the alignment marks and glue them together. (do this by halves, with the center seperate)
- once the glue has dried, remove the pins and sand the stepped edges down with a fine sanding block/sponge. take your time on the first pair, and do it till you're happy, not 'till it's perfect. check the left and right sides for consistency as you work
- once you're done, glue left-center-right together on pinned alignments, and do any final sanding.
- paint, attach, fly, break, rebuild!