Narrative:

I've had 2 near misses with radio sonde balloons in the past 16 months. Until the second incident, I thought this was a rare occurrence. The first near miss occurred in 9/87. While en route from vance AFB, ok, to barksdale AFB, la, in an MTR climbing through FL350 for FL370, directly over irw VORTAC, I observed a radio sonde balloon at my 12 O'clock, same altitude. By the time I saw the balloon I had no time to react since I was in cruise-climb at .9 mach. The balloon passed 100-200' off my right wing. The balloon envelope was made of clear or possible silverish material and its size was hard to estimate. There was a 10-15' tether attached to a fat cigar-shaped sonde. After the encounter, I wondered if the sonde would have penetrated my windscreen if I had collided with it. I never reported the incident since, after all, I didn't hit it. I just considered myself lucky for not hitting it and to have seen it in the first place. I never thought much of the incident until it happened again yesterday! The details of the second encounter are very similar to the first. This time I was the copilot on an mlt en route from little rock AFB to a TACAN fix near albuquerque, and return to little rock. The purpose of the flight was navigator training. We were cruising at FL220 over irw VORTAC on J6 at 280 KTS when I observed a radio sonde balloon similar to the one I had encountered here before. The balloon was at our altitude and passed 800-1000' off our right wing. I was very surprised to see another balloon under the same conditions as before. The purpose of this report is to point out these facts and to suggest that perhaps research be done to see how many others have had similar experiences. A collision with one of these devices could be catastrophic, especially if it were to be ingested into a turbine engine. The big sky little balloon theory may soon become obsolete. Perhaps en route charts should note locations and schedules for launches so that flight crews will be more vigilant to this hazard. Another solution would be to monitor the balloons with radar until they pose no hazard. I realize that I may be the only person to ever have seen 2 of these balloons in a career, but the circumstances surrounding these incidents were odd and suggested a potential problem.

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Original NASA ASRS Text

Title: MIL FLT CREW REPORTS NEAR MISS WITH WX BALLOON. IT WAS THE SECOND TIME IN 2 YEARS OVER THE SAME VOR FAC.

Narrative: I'VE HAD 2 NEAR MISSES WITH RADIO SONDE BALLOONS IN THE PAST 16 MONTHS. UNTIL THE SECOND INCIDENT, I THOUGHT THIS WAS A RARE OCCURRENCE. THE FIRST NEAR MISS OCCURRED IN 9/87. WHILE ENRTE FROM VANCE AFB, OK, TO BARKSDALE AFB, LA, IN AN MTR CLBING THROUGH FL350 FOR FL370, DIRECTLY OVER IRW VORTAC, I OBSERVED A RADIO SONDE BALLOON AT MY 12 O'CLOCK, SAME ALT. BY THE TIME I SAW THE BALLOON I HAD NO TIME TO REACT SINCE I WAS IN CRUISE-CLB AT .9 MACH. THE BALLOON PASSED 100-200' OFF MY RIGHT WING. THE BALLOON ENVELOPE WAS MADE OF CLEAR OR POSSIBLE SILVERISH MATERIAL AND ITS SIZE WAS HARD TO ESTIMATE. THERE WAS A 10-15' TETHER ATTACHED TO A FAT CIGAR-SHAPED SONDE. AFTER THE ENCOUNTER, I WONDERED IF THE SONDE WOULD HAVE PENETRATED MY WINDSCREEN IF I HAD COLLIDED WITH IT. I NEVER RPTED THE INCIDENT SINCE, AFTER ALL, I DIDN'T HIT IT. I JUST CONSIDERED MYSELF LUCKY FOR NOT HITTING IT AND TO HAVE SEEN IT IN THE FIRST PLACE. I NEVER THOUGHT MUCH OF THE INCIDENT UNTIL IT HAPPENED AGAIN YESTERDAY! THE DETAILS OF THE SECOND ENCOUNTER ARE VERY SIMILAR TO THE FIRST. THIS TIME I WAS THE COPLT ON AN MLT ENRTE FROM LITTLE ROCK AFB TO A TACAN FIX NEAR ALBUQUERQUE, AND RETURN TO LITTLE ROCK. THE PURPOSE OF THE FLT WAS NAVIGATOR TRNING. WE WERE CRUISING AT FL220 OVER IRW VORTAC ON J6 AT 280 KTS WHEN I OBSERVED A RADIO SONDE BALLOON SIMILAR TO THE ONE I HAD ENCOUNTERED HERE BEFORE. THE BALLOON WAS AT OUR ALT AND PASSED 800-1000' OFF OUR RIGHT WING. I WAS VERY SURPRISED TO SEE ANOTHER BALLOON UNDER THE SAME CONDITIONS AS BEFORE. THE PURPOSE OF THIS RPT IS TO POINT OUT THESE FACTS AND TO SUGGEST THAT PERHAPS RESEARCH BE DONE TO SEE HOW MANY OTHERS HAVE HAD SIMILAR EXPERIENCES. A COLLISION WITH ONE OF THESE DEVICES COULD BE CATASTROPHIC, ESPECIALLY IF IT WERE TO BE INGESTED INTO A TURBINE ENG. THE BIG SKY LITTLE BALLOON THEORY MAY SOON BECOME OBSOLETE. PERHAPS ENRTE CHARTS SHOULD NOTE LOCATIONS AND SCHEDULES FOR LAUNCHES SO THAT FLT CREWS WILL BE MORE VIGILANT TO THIS HAZARD. ANOTHER SOLUTION WOULD BE TO MONITOR THE BALLOONS WITH RADAR UNTIL THEY POSE NO HAZARD. I REALIZE THAT I MAY BE THE ONLY PERSON TO EVER HAVE SEEN 2 OF THESE BALLOONS IN A CAREER, BUT THE CIRCUMSTANCES SURROUNDING THESE INCIDENTS WERE ODD AND SUGGESTED A POTENTIAL PROB.

Data retrieved from NASA's ASRS site as of August 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.