Narrative:

Inbound to pdk (frequent visitor); at 7 miles obtained AWOS and at 6.5 made first radio call. Was watching G-1000 aircraft alerts plus ipad 'foreflight' aircraft alerts. There was no response to call as tower was very busy. Continued inbound and started slow descent from 3500 feet. At 5.5 miles still waiting for a comm break finally able to make a second call to tower; still no response. At 5 miles heard a call for an aircraft but for a different number. At 4.5 miles tower called me to confirm my call sign and issued an immediate climb to 2900 feet and left 360 as I was above another inbound aircraft. Initiated climb and turn then looked down to see a 172 directly below me. Neither the G-1000 nor foreflight showed his presence. After 360 I was cleared to follow 172 to left downwind and then landing. Upon contacting ground was asked to call the tower. Controller was very polite and informally we discussed the circumstances leading up the near miss. He acknowledged hearing my calls but was too busy with pattern traffic to respond. We agreed the best course of action for me would have been to remain outside his area (6 miles) until he could acknowledge.I am a very experienced pilot. I feel my scan is pretty good but was rusty using the G-1000 (focus) and as I was above the 172 never saw him until the tower call.

Google
 

Original NASA ASRS Text

Title: C182 pilot reported an NMAC with a C172 approaching PDK.

Narrative: Inbound to PDK (frequent visitor); at 7 miles obtained AWOS and at 6.5 made first radio call. Was watching G-1000 aircraft alerts plus iPad 'Foreflight' aircraft alerts. There was no response to call as Tower was very busy. Continued inbound and started slow descent from 3500 feet. At 5.5 miles still waiting for a Comm break finally able to make a second call to Tower; still no response. At 5 miles heard a call for an aircraft but for a different number. At 4.5 miles Tower called me to confirm my call sign and issued an immediate climb to 2900 feet and left 360 as I was above another inbound aircraft. Initiated climb and turn then looked down to see a 172 directly below me. Neither the G-1000 nor Foreflight showed his presence. After 360 I was cleared to follow 172 to left downwind and then landing. Upon contacting ground was asked to call the Tower. Controller was very polite and informally we discussed the circumstances leading up the near miss. He acknowledged hearing my calls but was too busy with pattern traffic to respond. We agreed the best course of action for me would have been to remain outside his area (6 miles) until he could acknowledge.I am a very experienced pilot. I feel my scan is pretty good but was rusty using the G-1000 (focus) and as I was above the 172 never saw him until the Tower call.

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.