i travelled through FRA 3 times in the last week, we had 30 minutes at security with added pat downs and screening. i thought i gonna miss my flight but turns out i was the first on the plane and the rest of the passengers were also stuck in security. with recent happenings, the security for all US bound flights is tough so expect it to take longer.soory but the connection time you have sounds too short, i wouldnt risk it.