Narrative:

We were level at 7;000 feet while being vectored by ewr approach. An aircraft appeared on our TCAS screen at our twelve o'clock position and approximately five miles. No altitude information was available on this target. We closed rapidly with the target and received an aural 'traffic' callout from our TCAS system. Both the first officer and I were scanning visually for the traffic. We were not sure if something was actually there as the controller had not alerted us to the presence of any close traffic and we sometimes get phantom contacts that appear in this manner on our TCAS system.as we merged with the target I suddenly spotted an aircraft at our twelve o'clock and slightly above us. I recognized it as a glider and we were approaching it from its six o'clock. As our closure rate was so fast there was no time to react and we passed directly under it with a vertical separation I estimate to be 200-300 feet. I immediately reported the presence of the glider to the controller who informed me the glider had no mode C and asked me what I estimated his altitude to be.

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Original NASA ASRS Text

Title: CRJ-700 Captain reported an NMAC with a non-mode C glider during arrival to EWR.

Narrative: We were level at 7;000 feet while being vectored by EWR Approach. An aircraft appeared on our TCAS screen at our twelve o'clock position and approximately five miles. No altitude information was available on this target. We closed rapidly with the target and received an aural 'traffic' callout from our TCAS system. Both the First Officer and I were scanning visually for the traffic. We were not sure if something was actually there as the Controller had not alerted us to the presence of any close traffic and we sometimes get phantom contacts that appear in this manner on our TCAS system.As we merged with the target I suddenly spotted an aircraft at our twelve o'clock and slightly above us. I recognized it as a glider and we were approaching it from its six o'clock. As our closure rate was so fast there was no time to react and we passed directly under it with a vertical separation I estimate to be 200-300 feet. I immediately reported the presence of the glider to the Controller who informed me the glider had no Mode C and asked me what I estimated his altitude to be.

Data retrieved from NASA's ASRS site as of July 2013 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.