General aviation pilot in class B airspace reported a close encounter with another aircraft.

Attributes
ACN	1755431
Time
Date	202008
Local Time Of Day	0601-1200
Place
Locale Reference	PHL.TRACON
State Reference	PA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Operating Under FAR Part	Part 91
Flight Phase	Descent
Route In Use	Direct
Flight Plan	VFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Commercial Flight Crew Flight Instructor Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 40 Flight Crew Total 3584 Flight Crew Type 825
Events
Anomaly	Conflict NMAC
Miss Distance	Vertical 400

Narrative:

Cleared through class B at 6;500 ft. VFR southbound. I requested and was granted from approach a descent to 4;500 ft. To maintain VFR. There were clouds in the vicinity. I began descent immediately and soon after was given traffic location; opposite direction; expedite descent; and 'if you don't see the traffic turn right to 270 degrees'. I immediately increased descent rate to 1;500 fpm and turned to 270 degrees. After a few moments I was told to continue on course. I continued on descent to 4;500 ft. And turned on course.

Original NASA ASRS Text

Title: General aviation pilot in Class B airspace reported a close encounter with another aircraft.

Narrative: Cleared through Class B at 6;500 ft. VFR southbound. I requested and was granted from approach a descent to 4;500 ft. to maintain VFR. There were clouds in the vicinity. I began descent immediately and soon after was given traffic location; opposite direction; expedite descent; and 'if you don't see the traffic turn right to 270 degrees'. I immediately increased descent rate to 1;500 fpm and turned to 270 degrees. After a few moments I was told to continue on course. I continued on descent to 4;500 ft. and turned on course.

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.