Would be nice to be able to find "runway surface" independent of the main airport type. For example, I want to fly my float plane across Alaska. Searching for "water" only brings up airports where "water" is the main airport type. There are many airports where there is a water runway in addition to the main hard-surface runway. These additional runways are reflected in your database, but there is no way to search for them. In the attached screenshot is the example of airport PAEN. There are 3 types of runway surfaces, but the search results will only find the "asphalt" surface, and not the "gravel" nor the "water".