I90 controller described an unsafe event when; prior to an anticipated runway configuration change; ...

Narrative:

Low IFR conditions in the area with a reported ceiling of 400 ft ovc at iah and we were running simultaneous operations to runways 8L and 8R. A BE35 was cleared for an ILS approach to runway 8L and was talking to the local north controller. Traffic management had coordinated an airport flow change and we were to begin landing to the west (26R/26L.) when the BE35 was very short final and leaving 400 ft the tower controller 'swung' the localizer creating for a potentially deadly situation. The bonanza lost all points of reference for navigation at a very critical phase of flight. The aircraft was IMC at the time and had to abandon the approach. This is like throwing a blindfold on the pilot. The pilot then began to drift right of course in the direction of an air carrier departure off of runway 9. There were also incredibly strong winds in the area associated with convective activity. Provide re-training.

Original NASA ASRS Text

Title: I90 Controller described an unsafe event when; prior to an anticipated runway configuration change; the Tower changed the localizer with an aircraft on the ILS; on short final and in IMC conditions.

Narrative: Low IFR conditions in the area with a reported ceiling of 400 FT OVC at IAH and we were running simultaneous operations to Runways 8L and 8R. A BE35 was cleared for an ILS approach to Runway 8L and was talking to the Local North Controller. Traffic Management had coordinated an airport flow change and we were to begin landing to the west (26R/26L.) When the BE35 was very short final and leaving 400 FT the Tower Controller 'swung' the localizer creating for a potentially deadly situation. The Bonanza lost all points of reference for navigation at a very critical phase of flight. The aircraft was IMC at the time and had to abandon the approach. This is like throwing a blindfold on the pilot. The pilot then began to drift right of course in the direction of an air carrier departure off of Runway 9. There were also incredibly strong winds in the area associated with convective activity. Provide re-training.

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.

Attributes
ACN	1059611
Time
Date	201301
Local Time Of Day	1201-1800
Place
Locale Reference	IAH.Airport
State Reference	TX
Aircraft 1
Make Model Name	Bonanza 35
Operating Under FAR Part	Part 91
Flight Phase	Descent
Flight Plan	IFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types

I90 controller described an unsafe event when; prior to an anticipated runway configuration change; the tower changed the localizer with an aircraft on the ILS; on short final and in IMC conditions.