Hennessy, author of trilogies about Britain's navy and cavalry (Lion at Sea, Soldier of the Queen), now begins--with rather less character-interest than before--a series devoted to England's wartime pilots. His awfully bland central hero: Dicken Quinney, a young wireless operator who discovers the thrill of aeroplanes in the summer of 1914, just about the time he also falls in love with beautiful local girl Annys Toshack. Annys isn't interested, however, so Dicken winds up sort-of-going with Annys' younger sister Zoe--a tomboyish engineer who's determined to be ""liberated"" by age 21. When war breaks out, Dicken joins the Royal Garrison Artillery, then--after rescuing monocled, blue-blooded pilot Willie Hatto--transfers to the Royal Flying Corps. And, aside from a brief consummation-scene back home with Zoe and a more soulful romance with Catholic girl Nicola in Italy, the rest of the novel is devoted to WW I aviation exploits--with technical details galore. Dicken trains first as an observer, then as a pilot. There are missions against the Germans over France, against the Austrians over Italy. The fast technological advances on both sides--from BEs (""They fly like bedpans with wings"") to Avros to Strutters to the Camel and the Bristol--are rigorously sketched in. The final section focuses on repeated efforts to bomb the Lugagnano power station-a mission that's heavy on casualties but relentlessly pursued by Diplock, the cowardly, climbing commander (""Parasol Percy"") who wins the hand of Dicken's adored Annys. And the wounded Dicken is last seen heading home to settle for Zoe--having been spurned by Nicola for religious reasons. Aside from his ultimate souring on war and his mild romantic conflict, however, Dicken hasn't much personal flavor. Nor are his contrasting cronies (flip Hatto, tough American Walter Foote) up to military-camaraderie snuff. So, to a greater extent than previous Hennessys, this is a military-saga installment of strictly narrow appeal--terrific for early-aviation buffs, off-limits for just about everybody else.