I have.
In January 1970, I was returning to Nam after an emergency family leave. I was routed through Treasure Island in San Francisco, whereupon I was chosen to escort two AWOLs back to Okinawa. Among my guard-duty issue was a .45 pistol, with ammo.
We flew a regular commercial flight from San Francisco to Honolulu, where I delivered the AWOLs to the brig, while we waited passage on a civilian charter. At the gate, I informed the attendants I was armed, showed the orders I carried, and they told me I would need to surrender the pistol to the captain upon boarding.
We boarded first, and I surrendered the pistol to the captain. After landing, we deplaned last, and the captain returned the pistol to me as we departed the aircraft.
A similar procedure was followed on the civilian charter from Honolulu to Okinawa. Times have changed.