Surviving a 17-hour "ultra-long-haul" flight in economy requires a strategic approach to comfort, hydration, and entertainment. First, dress in loose, breathable layers and wear compression socks to improve circulation and prevent swelling. Hydration is the golden rule; drink plenty of water and avoid excessive caffeine or alcohol, which can worsen jet lag and skin dryness. Bring a "comfort kit" containing a high-quality neck pillow, an eye mask, and noise-canceling headphones to help block out the cabin environment. To break up the time, pre-download a variety of entertainment, such as movies, podcasts, and audiobooks, and don't rely solely on the in-flight system. It is also essential to get up and move; aim to walk the aisles or perform seated stretches at least once every two hours to prevent stiffness. Finally, try to align your sleep schedule with your destination’s time zone as soon as you board, using a mild sleep aid if necessary to help your body adjust to the massive time shift.