A few people have tried to do this. Like pre-Resistance somebody had released a nuke by creating some custom CfgCloudlets, and then scripted a bunch of them to go off in a mushroom cloud expansion shape. It was pretty tight, but stalled your computer. Then Vit? released an F-15 addon that did what your trying to do. He just had an enormous hit to indirecthit range (as this increases blast goes up) that blew up everything including the plane if it was on the wrong side of the map. You really couldn't 'see' the blast, even though you might experience it. The most outstanding one was by the Chain of Command (CoC) who did a particle based nuclear explosion. You should try to rip the explosion scripts from them for your bomb. The nuke is part of their torpedoes pack, but their really isn't any ASW helos for OFP. But there are bombers and strike fighters that really have nuclear capable payloads like the F-15. You can probably link to their sight from the main OFPEC page or under the editing section.