Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Workload; Distraction; Confusion; Communication Breakdown
Conflict Airborne Conflict; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert
Procedure
Approx 2 hours into our flight (time and position were not noted); we were advised by ATC that an experimental balloon was in free fall near our position. We were also advised that the vehicle was unlit and had no transponder and no way to fix its position. ATC later reported that they had a primary target at our nine thirty position and eight miles and estimated the altitude at 45;000; but could not confirm that it was the plummeting balloon. Although we were looking for any trace of the balloon; we did not see; nor would we likely see it; due to the fact that it was unlit and it was a dark nightWe continued to our destination without further incident.Why the balloon failed is unknown. However; the fact that it did not have emergency lights and emergency transponder (or other way to absolutely fix it's position) when operating above commercial air routes is inexcusable. It would seem a simple thing to have an emergency aneroid switch that would activate when below a certain altitude; say 80;000 ft; thus giving position/altitude data; as well lighting for visual conformation (see and avoid) during hours of darkness.
ATC notified an air carrier at FL360 about an experimental balloon in a free fall descent through an estimated FL450; unlit and without a transponder during night conditions.