The pilot of a C210 was alerted to a near-mid-air-collision by the onboard traffic system. ATC was r...

Attributes
ACN	1351517
Time
Date	201604
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Cessna 210 Centurion / Turbo Centurion 210C 210D
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	IFR
Aircraft 2
Make Model Name	Cessna Single Piston Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Person 1
Function	Single Pilot
Qualification	Flight Crew Commercial Flight Crew Instrument
Experience	Flight Crew Last 90 Days 45 Flight Crew Total 4000 Flight Crew Type 1800
Events
Anomaly	ATC Issue All Types Conflict NMAC Deviation - Procedural Published Material / Policy Flight Deck / Cabin / Aircraft Event Other / Unknown
Miss Distance	Horizontal 500 Vertical 100

Narrative:

We were cleared direct to [destination airport] at 3000 feet and my traffic system sounded an alert showing a target almost directly ahead and 100 feet higher. I identified the traffic about 500 feet to my left as it went by. I asked the controller if he had noticed the target and he stated that he had been trying to call me and the pilot of the target plane but neither of us answered. I told him that I never heard his call. The other pilot said he had heard the call and had responded.since I'm not sure why I didn't hear the call; I can only assume that perhaps I was focused on other tasks or there was a communications problem. In the future I will try even harder to make sure that one ear is always listening. Perhaps the controllers should re-transmit if an alert is not acknowledged quickly.the traffic avoidance system was an important factor in this case and well worth the investment.

Original NASA ASRS Text

Title: The pilot of a C210 was alerted to a near-mid-air-collision by the onboard traffic system. ATC was reported to have tried to contact both aircraft; but an unknown communication problem existed.

Narrative: We were cleared direct to [destination airport] at 3000 feet and my traffic system sounded an alert showing a target almost directly ahead and 100 feet higher. I identified the traffic about 500 feet to my left as it went by. I asked the controller if he had noticed the target and he stated that he had been trying to call me and the pilot of the target plane but neither of us answered. I told him that I never heard his call. The other pilot said he had heard the call and had responded.Since I'm not sure why I didn't hear the call; I can only assume that perhaps I was focused on other tasks or there was a communications problem. In the future I will try even harder to make sure that one ear is always listening. Perhaps the controllers should re-transmit if an alert is not acknowledged quickly.The Traffic Avoidance System was an important factor in this case and well worth the investment.

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.