 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
Small aircraft pilot report on a potential conflict with a 'stealth' glider that was not picked up by joshua approach radar.
| Attributes | |
| ACN | 405478 |
| Time | |
| Date | 199806 |
| Day | Sat |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : mhv |
| State Reference | CA |
| Altitude | msl bound lower : 9500 msl bound upper : 9500 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | tracon : edw tower : ewr |
| Operator | general aviation : personal |
| Make Model Name | Any Unknown or Unlisted Aircraft Manufacturer |
| Operating Under FAR Part | Part 91 |
| Flight Phase | cruise other |
| Flight Plan | None |
| Aircraft 2 | |
| Make Model Name | Sail Plane |
| Operating Under FAR Part | other : other |
| Flight Phase | climbout : intermediate altitude cruise other |
| Flight Plan | None |
| Person 1 | |
| Affiliation | Other |
| Function | flight crew : single pilot |
| Qualification | pilot : instrument pilot : commercial |
| Experience | flight time last 90 days : 65 flight time total : 2000 flight time type : 1300 |
| ASRS Report | 405478 |
| Person 2 | |
| Affiliation | Other |
| Function | flight crew : single pilot |
| Qualification | pilot : private |
| Events | |
| Anomaly | conflict : airborne less severe non adherence : far |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : took evasive action |
| Consequence | Other |
| Miss Distance | horizontal : 1000 vertical : 500 |
| Supplementary | |
| Primary Problem | Aircraft |
| Air Traffic Incident | Pilot Deviation other |
Narrative:
This was not a near miss as I had the sailplane in sight from approximately 2 NM away. My concern is that the sailplane was not visible on radar. The glider had apparently caught a thermal column and was ascending at approximately 800 FPM to my altitude. My 'evasive' action was subtle as I gradually turned eastward to avoid being in the vertical path of the glider. I should have sent this report in earlier, but didn't think of it as a danger at the time. Upon reflecting, I decided that NASA/ASRS should have this information. For some reason (construction materials?, 'stealthy' shape?) the glider apparently never appeared on the radar of joshua approach. As the sailplane closed to estimate 1000 ft I asked joshua approach if it was on their radar and received a negative. The glider was all white and appeared to be a 2-SEATER. I do not know if they saw me. They did not appear to alter their spiral climb. In reviewing this event, I can think of nothing to recommend in changing procedures. Joshua approach was actively calling my traffic (other than the glider) and I was receiving excellent, professional, service from them. I am equally satisfied with my piloting during this event. I had my head-up and had spotted a potential conflict early. My reason for filing this report is to suggest further investigation or research on why some gliders, at some times, appear invisible to radar.
Original NASA ASRS Text
Title: SMA PLT RPT ON A POTENTIAL CONFLICT WITH A 'STEALTH' GLIDER THAT WAS NOT PICKED UP BY JOSHUA APCH RADAR.
Narrative: THIS WAS NOT A NEAR MISS AS I HAD THE SAILPLANE IN SIGHT FROM APPROX 2 NM AWAY. MY CONCERN IS THAT THE SAILPLANE WAS NOT VISIBLE ON RADAR. THE GLIDER HAD APPARENTLY CAUGHT A THERMAL COLUMN AND WAS ASCENDING AT APPROX 800 FPM TO MY ALT. MY 'EVASIVE' ACTION WAS SUBTLE AS I GRADUALLY TURNED EASTWARD TO AVOID BEING IN THE VERT PATH OF THE GLIDER. I SHOULD HAVE SENT THIS RPT IN EARLIER, BUT DIDN'T THINK OF IT AS A DANGER AT THE TIME. UPON REFLECTING, I DECIDED THAT NASA/ASRS SHOULD HAVE THIS INFO. FOR SOME REASON (CONSTRUCTION MATERIALS?, 'STEALTHY' SHAPE?) THE GLIDER APPARENTLY NEVER APPEARED ON THE RADAR OF JOSHUA APCH. AS THE SAILPLANE CLOSED TO ESTIMATE 1000 FT I ASKED JOSHUA APCH IF IT WAS ON THEIR RADAR AND RECEIVED A NEGATIVE. THE GLIDER WAS ALL WHITE AND APPEARED TO BE A 2-SEATER. I DO NOT KNOW IF THEY SAW ME. THEY DID NOT APPEAR TO ALTER THEIR SPIRAL CLB. IN REVIEWING THIS EVENT, I CAN THINK OF NOTHING TO RECOMMEND IN CHANGING PROCS. JOSHUA APCH WAS ACTIVELY CALLING MY TFC (OTHER THAN THE GLIDER) AND I WAS RECEIVING EXCELLENT, PROFESSIONAL, SVC FROM THEM. I AM EQUALLY SATISFIED WITH MY PILOTING DURING THIS EVENT. I HAD MY HEAD-UP AND HAD SPOTTED A POTENTIAL CONFLICT EARLY. MY REASON FOR FILING THIS RPT IS TO SUGGEST FURTHER INVESTIGATION OR RESEARCH ON WHY SOME GLIDERS, AT SOME TIMES, APPEAR INVISIBLE TO RADAR.
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.