Vny controller reports of observing an aircraft roll right and left; then regain control. Controller...

Attributes
ACN	1257832
Time
Date	201504
Local Time Of Day	1201-1800
Place
Locale Reference	VNY.Tower
State Reference	CA
Environment
Light	Daylight
Aircraft 1
Make Model Name	Helicopter
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	VFR
Aircraft 2
Make Model Name	Small Aircraft
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	VFR
Person 1
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (mon) 4
Events
Anomaly	Conflict Airborne Conflict Inflight Event / Encounter Wake Vortex Encounter Inflight Event / Encounter Loss Of Aircraft Control

Narrative:

Aircraft X was on short final to land on B at B1. The pilot was advised of aircraft Y on short final to land runway 16L. The aircraft X sad he was offsetting slightly to the east to make more room for aircraft Y. Once aircraft Y was abeam aircraft X it began to roll hard right and then hard left as I assume the pilot was trying to correct and regain control of the aircraft. Aircraft Y landed without incident. Aircraft X ended up going around and landed safely without incident on the next time around. The loss of control appears to have been caused by wake turbulence generated by the rotor wash. Issue a caution wake turbulence to all aircraft on final to 16L with a helicopter on short final to B1. Delay clearing a helicopter to land B1 if traffic is on short final to 16L.

Original NASA ASRS Text

Title: VNY Controller reports of observing an aircraft roll right and left; then regain control. Controller states it was possibly due to rotor wash from a helicopter.

Narrative: Aircraft X was on short final to land on B at B1. The pilot was advised of Aircraft Y on short final to land Runway 16L. The Aircraft X sad he was offsetting slightly to the East to make more room for Aircraft Y. Once Aircraft Y was abeam Aircraft X it began to roll hard right and then hard left as I assume the pilot was trying to correct and regain control of the aircraft. Aircraft Y landed without incident. Aircraft X ended up going around and landed safely without incident on the next time around. The loss of control appears to have been caused by wake turbulence generated by the rotor wash. Issue a caution wake turbulence to all aircraft on final to 16L with a helicopter on short final to B1. Delay clearing a helicopter to land B1 if traffic is on short final to 16L.

Data retrieved from NASA's ASRS site 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.

Vny controller reports of observing an aircraft roll right and left; then regain control. Controller states it was possibly due to rotor wash from a helicopter.