Small aircraft had near midair collision with WX balloon.

Attributes
ACN	298633
Time
Date	199503
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : jst
State Reference	PA
Altitude	msl bound lower : 5500 msl bound upper : 5500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	None
Aircraft 2
Operator	other
Make Model Name	Balloon
Operating Under FAR Part	other : unknown
Flight Phase	climbout : intermediate altitude
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 9 flight time total : 152
ASRS Report	298633
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Resolutory Action	none taken : insufficient time
Consequence	Other
Miss Distance	horizontal : 30 vertical : 0

Narrative:

On a heading of 45 degrees at 5500 ft MSL, I observed an object at same altitude. Due to the speed the object passed on my starboard side at a distance of 30 ft, I believe we were traveling in same direction. Jst tower has reported radio controled aircraft activity in the area. I don't believe this was an radio cont plane. Possible WX balloon, but I have never seen a photograph of one.

Original NASA ASRS Text

Title: SMA HAD NMAC WITH WX BALLOON.

Narrative: ON A HDG OF 45 DEGS AT 5500 FT MSL, I OBSERVED AN OBJECT AT SAME ALT. DUE TO THE SPD THE OBJECT PASSED ON MY STARBOARD SIDE AT A DISTANCE OF 30 FT, I BELIEVE WE WERE TRAVELING IN SAME DIRECTION. JST TWR HAS RPTED RADIO CTLED ACFT ACTIVITY IN THE AREA. I DON'T BELIEVE THIS WAS AN RADIO CONT PLANE. POSSIBLE WX BALLOON, BUT I HAVE NEVER SEEN A PHOTOGRAPH OF ONE.

Data retrieved from NASA's ASRS site as of July 2007 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.