In 9.2 we added the Emergency Assistance Mode. Just tap the Red Emergency Alert button at the top left corner of the NRST page. This will drive the list to All Airports, and disregard any length filters and such. In an emergency, you'll take a shorter runway. At altitude, it will color code the airport direction icon and show Green, Yellow and Red. I'm guessing the colors speak for themselves. It's very conservative and is also based on the Glide Ratio in the Aircraft Profile, so to maximize accuracy, you want to have the correct glide ration entered. Here is an image.
Note: It now shows "All Airports" at the top, when in Emergency Assistance Mode.