Unable to migrate from AIR 14.0 to 16.0 on iOS

Good morning to everybody

As you can think, I have a problem with Flash Builder:

I'm developing an app for android and iOS. Until now, I've worked with Flex 4.14.1 and AIR 14.0 (at the start of my project, this was the last update available). And it works fine.

Now, as you now, apple requires 64 bit compatibilities, available from AIR 16.0. So I've tried to migrate to AIR 16.0.

And now the problem: on the Flash Builder simulator and on an android device the app works well, but on the iPhone 5 it crashes after 2-3 seconds. And obviously I don't now why.

Someone else has a similar problem? Could you give me some suggestions to resolve this issue?

Thanks in advance

Mario