On several occasions I have down loaded the charts in the AIP. When planning the trip they are in the memory. After shutting down the iPad and restarting for the trip the AIP charts have disappeared. Have I some incorrect settings?

Hi,

How do you download them? By using the "download AIP/product" menu? By using the "search plate" menu? By creating a route?
In the first case, all plates are downloaded and remain available, even when offline.
In the other cases, it's a one by one download and plates are not cached/available offline.

So, if you want plates to be available offline, you need to download them all from time to time, using the map/tools/download menu.

M