Air carrier flight crew and an enroute controller reported an airborne conflict occurred when the fl...

Attributes
ACN	1737581
Time
Date	202003
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Aircraft 2
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 694
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance

Narrative:

Center gave us a clearance to descend from FL390 to FL290. I read it back and we started a descent. As we were descending we did get a TCAS alert of traffic less than 1;000 feet; but the PF (pilot flying) went to vertical speed to slow our rate down to avoid an RA. About 400 feet in descent; ATC queried us if we were still level at FL390. We said no that we were in a descent to FL290. He proceeded to say that we were not supposed to descend. I told him that's what he gave to us. He said no it was for our company [callsign]. He asked them; and of course; they were descending to FL290. So we must have gotten blocked on our transmission. That's probably why ATC didn't correct us because he only heard [the callsign]. The frequency was very congested due to center and surrounding airports being closed at the time; and that was also why we were running late. There was no issue with the traffic off of our right wing that we got a traffic alert on. Our company asked if their altitude was corrected because of doubt. ATC said 'yes.' later ATC said that it was not a problem.

Original NASA ASRS Text

Title: Air carrier flight crew and an enroute Controller reported an airborne conflict occurred when the flight crew took a descent clearance intended for another aircraft. Controller suggested that increased workload associated with COVID-19 procedures contributed to the event.

Narrative: Center gave us a clearance to descend from FL390 to FL290. I read it back and we started a descent. As we were descending we did get a TCAS alert of traffic less than 1;000 feet; but the PF (Pilot Flying) went to Vertical Speed to slow our rate down to avoid an RA. About 400 feet in descent; ATC queried us if we were still level at FL390. We said no that we were in a descent to FL290. He proceeded to say that we were not supposed to descend. I told him that's what he gave to us. He said no it was for our Company [callsign]. He asked them; and of course; they were descending to FL290. So we must have gotten blocked on our transmission. That's probably why ATC didn't correct us because he only heard [the callsign]. The frequency was very congested due to Center and surrounding airports being closed at the time; and that was also why we were running late. There was no issue with the traffic off of our right wing that we got a Traffic Alert on. Our Company asked if their altitude was corrected because of doubt. ATC said 'yes.' Later ATC said that it was not a problem.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Air carrier flight crew and an enroute controller reported an airborne conflict occurred when the flight crew took a descent clearance intended for another aircraft. Controller suggested that increased workload associated with covid-19 procedures contributed to the event.