Finally found an Aero H/H+ call that was encrypted. Supported crypto services on Aero are US-STU-III (Secure Telephone Unit), STE (Secure Terminal Equipment), FNBDT (Future Narrow Band Digital Terminal). Not clear which service this actually is but I suspect it’s STE. Nice to see encryption being used appropriately. This particular aircraft is a Gulfstream and is registered to Bank of Utah.
This call was not likely intended to be routed via the AMBE voice path. The AMBE codec bandwidth is not sufficient to run crypto.