Air carrier at flight level reported a near miss with a WX balloon.

Attributes
ACN	152950
Time
Date	199008
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : grb
State Reference	WI
Altitude	msl bound lower : 35000 msl bound upper : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp tower : bur
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 4 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 8 flight time total : 2000
ASRS Report	152950
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : nmac other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Miss Distance	horizontal : 300 vertical : 0
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

I received a report from the pilot of air carrier X of missing a WX balloon by approximately 300'. The aircraft was en route from ewr to sfo level at FL350. No notice was given to ZMP ARTCC of the launch of a WX balloon so no advisory was given to other aircraft until report by air carrier X. I suggest that WX balloons carry a transponder type equipment so the balloon can be painted on radar so advisories to aircraft can be given. The situation as it stands today I feel compromises safety should be dealt with immediately. Callback conversation with reporter revealed the following information. Reporter gave ATC experience and aircraft type. No prior information received on WX balloon. Report of near miss given to supervisor. Not known what supervisor did with information. Reporter states he had a similar incident while flying at low altitude and understands problem. Reporter has approximately 2000 hours flying time.

Original NASA ASRS Text

Title: ACR AT FLT LEVEL REPORTED A NEAR MISS WITH A WX BALLOON.

Narrative: I RECEIVED A RPT FROM THE PLT OF ACR X OF MISSING A WX BALLOON BY APPROX 300'. THE ACFT WAS ENRTE FROM EWR TO SFO LEVEL AT FL350. NO NOTICE WAS GIVEN TO ZMP ARTCC OF THE LAUNCH OF A WX BALLOON SO NO ADVISORY WAS GIVEN TO OTHER ACFT UNTIL RPT BY ACR X. I SUGGEST THAT WX BALLOONS CARRY A XPONDER TYPE EQUIP SO THE BALLOON CAN BE PAINTED ON RADAR SO ADVISORIES TO ACFT CAN BE GIVEN. THE SITUATION AS IT STANDS TODAY I FEEL COMPROMISES SAFETY SHOULD BE DEALT WITH IMMEDIATELY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. RPTR GAVE ATC EXPERIENCE AND ACFT TYPE. NO PRIOR INFO RECEIVED ON WX BALLOON. RPT OF NEAR MISS GIVEN TO SUPVR. NOT KNOWN WHAT SUPVR DID WITH INFO. RPTR STATES HE HAD A SIMILAR INCIDENT WHILE FLYING AT LOW ALT AND UNDERSTANDS PROB. RPTR HAS APPROX 2000 HRS FLYING TIME.

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.