Well, you're doing it wrong.
Zoom out of your current location... Swipe to the general location of the park, then zoom in and out of that area and around it. It'll take you 15-30 seconds.
The real challenge is remembering to cache the maps prior to connecting to the Phantom network. Most of the time, you'll get too excited to fire up the aircraft that you'd inadvertently skip a few vital steps in your pre-flight checklist.
Zoom out of your current location... Swipe to the general location of the park, then zoom in and out of that area and around it. It'll take you 15-30 seconds.
The real challenge is remembering to cache the maps prior to connecting to the Phantom network. Most of the time, you'll get too excited to fire up the aircraft that you'd inadvertently skip a few vital steps in your pre-flight checklist.