Helicopter pilot reported being flown under by another helicopter on two occasions within a few minu...

Attributes
ACN	1369762
Time
Date	201607
Local Time Of Day	1201-1800
Place
Locale Reference	SMO.Airport
State Reference	CA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Helicopter
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	None
Flight Plan	None
Aircraft 2
Make Model Name	Helicopter
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Rotorcraft Flight Crew Instrument Flight Crew Commercial Flight Crew Flight Instructor
Experience	Flight Crew Last 90 Days 40 Flight Crew Total 7500 Flight Crew Type 4000
Events
Anomaly	Conflict Airborne Conflict
Miss Distance	Horizontal 0 Vertical 150

Narrative:

I was flying an aircraft on a law enforcement mission. I was over the hollywood area in uncontrolled airspace near hollywood high school. I received a tcad alert coming from my six o'clock position. I made a position report on the los angeles basin frequency; and stated I was at 900 feet. I heard the other aircraft say they had me in sight and the tcad indicated that the other traffic was overtaking me and 300 feet below my altitude. I told my passenger; a tactical flight officer working as a law enforcement crew member; to look for the traffic. He advised me that the traffic was passing underneath on the right side of our aircraft so I banked left; turning northbound. I directed him to take photos with his cell phone as I came around to acquire the other aircraft's location. Several minutes later; I was travelling southbound from the location toward park labrea and reported my altitude at 900 ft MSL. My position report was replied to by [a pilot] who stated he had me in sight and gave his altitude as 750 ft. I received another tcad alert indicating the traffic was converging on my position from my 8 o'clock. The same helicopter passed underneath me. There was approximately 150 ft between the two aircraft. I believe this was the same aircraft that flew under my aircraft in may of 2015.

Original NASA ASRS Text

Title: Helicopter pilot reported being flown under by another helicopter on two occasions within a few minutes of each other. The two aircraft were in communication and the other helicopter pilot had the reporter in sight.

Narrative: I was flying an aircraft on a law enforcement mission. I was over the Hollywood area in uncontrolled airspace near Hollywood high school. I received a TCAD alert coming from my six o'clock position. I made a position report on the Los Angeles Basin Frequency; and stated I was at 900 feet. I heard the other aircraft say they had me in sight and the TCAD indicated that the other traffic was overtaking me and 300 feet below my altitude. I told my passenger; a tactical flight officer working as a law enforcement crew member; to look for the traffic. He advised me that the traffic was passing underneath on the right side of our aircraft so I banked left; turning northbound. I directed him to take photos with his cell phone as I came around to acquire the other aircraft's location. Several minutes later; I was travelling southbound from the location toward Park LaBrea and reported my altitude at 900 ft MSL. My position report was replied to by [a pilot] who stated he had me in sight and gave his altitude as 750 ft. I received another TCAD alert indicating the traffic was converging on my position from my 8 o'clock. The same helicopter passed underneath me. There was approximately 150 ft between the two aircraft. I believe this was the same aircraft that flew under my aircraft in May of 2015.

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.