Narrative:

While flying the ILS to runway 4 at houston hobby airport, we experienced a near miss with an unidented aircraft. We were in the clouds under IFR conditions, and our TCASII was inoperative. We were 5-6 mi from the airport when the aircraft, flying in a northwest direction crossed our approach path from right to left. The controller advised us of the traffic when he was 1/2 to 1 mi away. ATC had no radio contact with the other aircraft, but mode C readout indicated he was at our altitude of 2000 ft AGL. The controller gave us an immediate right turn to avoid the traffic. ATC said he came within 1/4 mi of our position. When the traffic cleared we continued the ILS. The controller said he would try and track down the other aircraft for identify and possible violation.

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Original NASA ASRS Text

Title: ACR ACFT CONDUCTING AN ILS APCH IN IMC CONDITIONS HAS ENCOUNTER WITH UNCTLED XING TFC.

Narrative: WHILE FLYING THE ILS TO RWY 4 AT HOUSTON HOBBY ARPT, WE EXPERIENCED A NEAR MISS WITH AN UNIDENTED ACFT. WE WERE IN THE CLOUDS UNDER IFR CONDITIONS, AND OUR TCASII WAS INOP. WE WERE 5-6 MI FROM THE ARPT WHEN THE ACFT, FLYING IN A NW DIRECTION CROSSED OUR APCH PATH FROM R TO L. THE CTLR ADVISED US OF THE TFC WHEN HE WAS 1/2 TO 1 MI AWAY. ATC HAD NO RADIO CONTACT WITH THE OTHER ACFT, BUT MODE C READOUT INDICATED HE WAS AT OUR ALT OF 2000 FT AGL. THE CTLR GAVE US AN IMMEDIATE R TURN TO AVOID THE TFC. ATC SAID HE CAME WITHIN 1/4 MI OF OUR POS. WHEN THE TFC CLRED WE CONTINUED THE ILS. THE CTLR SAID HE WOULD TRY AND TRACK DOWN THE OTHER ACFT FOR IDENT AND POSSIBLE VIOLATION.

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.