The Titan Sub prototype was lost near Seattle Bay, and the iPhone used it to reorient itself

Ninety minutes later and 130 meters deeper, we were completely lost. First, the thruster software failed and we found ourselves hovering just above the seabed. Now the submarine’s compass began to work. The shipwreck we wanted to explore, the train ferry that once carried Teddy Roosevelt, was nowhere to be seen. The only thing I could observe beyond the Cyclops’ front dome were the occasional salmon dancing in the icy water.

As I began to feel the cold seep through the submarine’s steel hull, Rush asked me to open the compass app on my iPhone. He wanted to compare it with the one on his phone. The headlines didn’t add up, but he restarted the thrusters and we headed in what he thought was the right direction.

“You’re going in exactly the wrong direction,” said a faint voice transmitted over an acoustic link from a support ship tracking us on the surface. We finally located the sunken ship, its rotting bow visible in the light of the Cyclops searchlight. It was an otherworldly experience, made even more exciting by the hint of danger.

Back at the dock, Rush shook off the problems we had encountered. That’s why OceanGate started with Cyclops 1, he said, and not with anything that could dive deeper. “I could have built a multimillion-dollar version, and suddenly I have to invent really stupid things like a magnetic compass,” he told me. “Cyclops 1 is preparing us. When we make Cyclops 2, all these bugs will be fixed.