In an interview with Time, Trump recalled the conversation.

I said, “You don’t use steam anymore for catapult?” “No sir.” I said, “Ah, how is it working?” “Sir, not good. Not good. Doesn’t have the power. You know the steam is just brutal. You see that sucker going and steam’s going all over the place, there’s planes thrown in the air.”

It sounded bad to me. Digital. They have digital. What is digital? And it’s very complicated, you have to be Albert Einstein to figure it out. And I said — and now they want to buy more aircraft carriers. I said, “What system are you going to be—” “Sir, we’re staying with digital.” I said, “No you’re not. You going to goddamned steam, the digital costs hundreds of millions of dollars more money and it’s no good.”

Foreign Policy – Trump Wants New Aircraft Carriers to Turn Back to ‘Goddamned Steam’ Power Catapults