Clearly modeled after On the Beach, this nuclear-disaster novel is a ho-hum affair--except for one aviation-suspense gimmick that doesn't take over until late in the action. It's 1985, and for two years America has been gripped by the lawlessness brought on by total energy breakdown and exodus from the cities. But this energy catastrophe, which fills the whole first third of the book, is weakly drawn and peopled with dull stereotypes. Things pick up a bit with the arrival of Captain Jonah Scott--a British Boeing 797 pilot recently saved from alcoholism (his wife Julie burned alive in the National Front riots) by loving Chief Flight Attendant Kate Monahan. Jonah and Kate wind up in apocalyptic Manhattan, where Jonah is caught in a bloodbath riot; he's saved by wounded Vietnam vet John Capel. So Jonah decides to bring John along (as a stowaway) on his flight to Heathrow aboard Delta Tango--at a time when Kennedy International is mobbed by people screaming to be carried to safety overseas. And for a while the novel seems to be in Airport territory--as Jonah takes off with 615 aboard the huge plane, with unrewarding character-closeups on a number of crewmembers and passengers. Finally, then, Graham gets to his one strong plot idea: Israel has just used an A-bomb; a massive strike and counterstrike have pretty much wiped out mankind, leaving a thick radiation belt everywhere; so where will Delta Tango land? Its first forced landing is on the island of Terceira in the Azores, where investigations in a military library reveal that the McMurdo base in Antarctica has supplies sufficient for 1000 people for seven years. So it's on to Antarctica--along with the crew and passengers of a Russian air freighter which has also landed (including a woman pilot who falls for Jonah). And these two plane-fuls will perhaps be the basis for a new human race of ""Alphans."" Familiar future-history situations, weakly drawn characters--but the where-to-land? suspense here may be grabbing enough to attract air-thriller readers and carry them along.