A helicopter pilot took evasive action from a light twin near lbx runway 17 while both aircraft were...

Narrative:

During a helicopter training exercise (2 pilots) on a 45 degree to runway short final runway 17. Landing with a simulated hydraulic system failure. We made a last minute check to make sure no one was landing on the runway. Upon looking to the north saw a light twin on very short final for runway 17. Both aircraft were closing in on the approach end of the runway at the same height and distance for landing. The twin was to our right and slightly behind our field of vision about 200 ft and closing. Once the other aircraft was spotted we terminated the approach to a high hover and the twin continued with its landing. There was no further incident. Communications would be the main contributing factor. The airport was very quiet and we had been monitoring approach control and the local CTAF frequency as well as making our own traffic calls. We never heard any radio calls from the twin until just before he departed the airfield. I also believe TCAS in either aircraft would have been helpful in preventing this. The fact that texas gulf coast regional (lbx) and houston southwest (axh) share the same frequency and are very close to each other and the high amount of radio calls at houston southwest may have contributed to the confusion.

Original NASA ASRS Text

Title: A helicopter pilot took evasive action from a light twin near LBX Runway 17 while both aircraft were on short final and no prior CTAF communications were heard.

Narrative: During a helicopter training exercise (2 pilots) on a 45 degree to runway short final Runway 17. Landing with a simulated hydraulic system failure. We made a last minute check to make sure no one was landing on the runway. Upon looking to the north saw a light twin on very short final for Runway 17. Both aircraft were closing in on the approach end of the runway at the same height and distance for landing. The twin was to our right and slightly behind our field of vision about 200 FT and closing. Once the other aircraft was spotted we terminated the approach to a high hover and the Twin continued with its landing. There was no further incident. Communications would be the main contributing factor. The airport was very quiet and we had been monitoring Approach Control and the local CTAF frequency as well as making our own traffic calls. We never heard any radio calls from the twin until just before he departed the airfield. I also believe TCAS in either aircraft would have been helpful in preventing this. The fact that Texas Gulf Coast Regional (LBX) and Houston Southwest (AXH) share the same frequency and are very close to each other and the high amount of radio calls at Houston Southwest may have contributed to the confusion.

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	1025133
Time
Date	201207
Local Time Of Day	1201-1800
Place
Locale Reference	LBX.Airport
State Reference	TX
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Bell Helicopter 222
Operating Under FAR Part	Part 135
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	VFR
Aircraft 2
Make Model Name	Small Aircraft Low Wing 2 Eng Retractable Gear
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Person 1
Function	Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Flight Instructor
Experience	Flight Crew Last 90 Days 100 Flight Crew Total 10000 Flight Crew Type 10000
Events
Anomaly	Conflict NMAC
Miss Distance	Horizontal 200 Vertical 0

A helicopter pilot took evasive action from a light twin near lbx runway 17 while both aircraft were on short final and no prior CTAF communications were heard.