A pilot practicing proficiency maneuvers at 5;000 ft prior to a VFR approach to pym has a near miss ...

Narrative:

I was returning from a VFR cross country flight with a friend in the passenger seat. Our plane was had a garmin GNS430 and a mode C transponder; we were using the CTAF frequency at pym at the time. We were planning on entering the traffic pattern at pym. There was a lot of aircraft flying in under 2;000 ft MSL. A plane called a 4 mile final into runway 15; we were close to that area and we decided to do a climbing turn to look for the traffic. The winds started to shift to favor [runway] 24 but the other aircraft in the pattern were not changing runways. We decided to climb up to about 5;000 ft MSL over the shore line and do a few practice maneuvers to wait and let the other aircraft land or change runways.we did our clearing turns and did a few chandelles; steep turns; and lazy eights. On the last lazy eight; as we're returning to wings level we see an aircraft fly very close right under our left wing. It seemed to be about 300 ft below us and within 200 ft horizontally; it might have been closer; but at the rate that it flew under us it was very difficult to tell. I applied full power and made a 60 degree bank right turn immediately to try to avoid this aircraft. We thought it was a light twin. It looked like it made no efforts to evade us. They must have been on with ATC; as they were at 5;000 ft going at least 150 KTS; which would put them in the boston bravo in a matter of minutes. After this event; the pattern was clear and we made an uneventful landing. I don't know what was going on in the other aircraft; but with the changing attitude of my aircraft in the lazy eight; and the closing speed of the conflicting traffic; left for about a second to react and turn. The light twin being fast; relatively small; and in the blind spot under our nose was able to get too close without us seeing them. Ads-B would have been invaluable in this situation; as we would be able to see the other aircraft on the display quicker and easier than trying to spot it whilst performing a maneuver.

Original NASA ASRS Text

Title: A pilot practicing proficiency maneuvers at 5;000 FT prior to a VFR approach to PYM has a near miss with an aircraft which he assumed was IFR because it was not on PYM CTAF.

Narrative: I was returning from a VFR cross country flight with a friend in the passenger seat. Our plane was had a Garmin GNS430 and a Mode C transponder; we were using the CTAF frequency at PYM at the time. We were planning on entering the traffic pattern at PYM. There was a lot of aircraft flying in under 2;000 FT MSL. A plane called a 4 mile final into Runway 15; we were close to that area and we decided to do a climbing turn to look for the traffic. The winds started to shift to favor [Runway] 24 but the other aircraft in the pattern were not changing runways. We decided to climb up to about 5;000 FT MSL over the shore line and do a few practice maneuvers to wait and let the other aircraft land or change runways.We did our clearing turns and did a few chandelles; steep turns; and lazy eights. On the last lazy eight; as we're returning to wings level we see an aircraft fly very close right under our left wing. It seemed to be about 300 FT below us and within 200 FT horizontally; it might have been closer; but at the rate that it flew under us it was very difficult to tell. I applied full power and made a 60 degree bank right turn immediately to try to avoid this aircraft. We thought it was a light twin. It looked like it made no efforts to evade us. They must have been on with ATC; as they were at 5;000 FT going at least 150 KTS; which would put them in the Boston Bravo in a matter of minutes. After this event; the pattern was clear and we made an uneventful landing. I don't know what was going on in the other aircraft; but with the changing attitude of my aircraft in the lazy eight; and the closing speed of the conflicting traffic; left for about a second to react and turn. The light twin being fast; relatively small; and in the blind spot under our nose was able to get too close without us seeing them. ADS-B would have been invaluable in this situation; as we would be able to see the other aircraft on the display quicker and easier than trying to spot it whilst performing a maneuver.

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.

Attributes
ACN	1176367
Time
Date	201405
Local Time Of Day	1201-1800
Place
Locale Reference	PYM.Airport
State Reference	MA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	None
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft Low Wing 2 Eng Retractable Gear
Flight Phase	Cruise
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Instrument Flight Crew Private
Experience	Flight Crew Last 90 Days 40 Flight Crew Total 235 Flight Crew Type 100
Events
Anomaly	Conflict NMAC
Miss Distance	Horizontal 200 Vertical 300

A pilot practicing proficiency maneuvers at 5;000 ft prior to a VFR approach to pym has a near miss with an aircraft which he assumed was IFR because it was not on pym CTAF.