The B-17 he was piloting had lost two of its four engines to enemy fire, and as Si Spiegel surveyed the ruined landscape, he had one thought: We have to get behind the Russian front.

As part of the Allied raid on Berlin, his bomber had dropped its payload over the German capital, but he’d been hit with flak and would almost certainly not make it back to the base in England. No pilot wanted to get shot down over Nazi Germany, especially not a Jewish pilot.

Mr. Spiegel had essentially bluffed his way into the cockpit as a skinny teenager from Greenwich Village, trusting he’d figure it out as he went. This was no different. He told his crew they were headed for Poland; they could get their parachutes ready, but were not to bail out unless he gave the order. They would attempt an emergency landing.

Si Spiegel is one of the last bomber pilots of World War II still with us. I met him on a windy December morning in 2019. I happened to overhear him discussing Eleanor Roosevelt’s love of aviation in front of her sculpture on Riverside Drive. I couldn’t help butting in — I was writing a biography of Mrs. Roosevelt’s great friend Amelia Earhart. He seemed wary of my enthusiasm, but when he saw the Lower East Side address on my business card, he smiled. I had inherited my grandparents’ old apartment in one of the International Ladies’ Garment Workers' Union buildings, the same address where his union parents had lived.

He invited me over for coffee that week. What began as a way to do research for my book — there aren’t many living aviators from that era, after all — evolved into a series of conversations over weeks and then months. His considerable charm and sharp memory were matched by his stamina — he would happily talk for hours but only if they didn’t conflict with his regular gym workouts.

But he was 95 then (now 97), and he clearly had been needing an audience for his stories. In the first hour of our first meeting, I learned that he flew dozens of critical and dangerous missions during the war, had saved his crew by successfully crash-landing an enormous bomber in no-man’s land — and then helped orchestrate a daring escape back out.

Perhaps most remarkable: Mr. Spiegel is improbably best known as “the king of the artificial Christmas tree.”