Large Transport
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 5
Confusion; Communication Breakdown
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Air Traffic Control Separated Traffic
Procedure; Aircraft
A company has been launching unmanned weather balloons from an airport for several months.  They are launched 3 to 5 at a time and climb slowly (approximately 3 hundred FPM) to an altitude above FL600; remain at altitude for a while; and then descend.  They are equipped with transponders and are 'tracked' by the FLM via a website that is not accurate.  The specific incident that occurred today was Mode C not showing on one of the tracked balloon targets and an aircraft was passing about 1/2 mile from the balloon target.  I informed the Aircraft X about the balloon and asked him if he wanted a vector he said yes and confirmed it passed about 4 miles off his left about 5;000 feet above them.  According to the Company website the FLM was monitoring; the balloon was at approximately 70;000 feet; which was completely incorrect.  Without the vector and some distrust of information being told to me; this could have been very close to a NMAC.    This is not an isolated incident and has occurred several times before.  It's hard to say what would make this safer to the flying public other than set up a TFR around this operation.
Controller reports of unmanned weather balloons that have a tracking system with altitude reply that is incorrect.  This causes problems with aircraft in the NAS by not knowing exactly where the balloons are.