Narrative:

I had passengers loaded on helicopter X. After receiving the thumbs up from the ramper; I made a radio call on CTAF; indicating I was lifting to the south. Approaching queens gate and leveling off at 500'; I made another radio call; indicating helicopter X at queens gate southbound. I noticed a traffic indication on my GPS showing a target very close and 100' below. I looked around but did not see anything. Within about 3 seconds; I saw helicopter Y to my left and slightly lower; traveling at a high speed west bound from left to right. I immediately performed a cyclic climbing evasive maneuver to avoid his rotor disc; missing the aircraft by only about 10-20 feet. I tried to call the other helicopter several times but received no response. He or she apparently did not see me at all; as they took no evasive action.[an individual] from the base called me to discuss the matter. He indicated no violation could occur; as this was uncontrolled airspace. I informed him that this is a busy area and aircraft should be announcing positions and intentions as indicated on the appropriate aeronautical charts. He told me they use [a different frequency]; which is on the sectional charts. I have been informed that that frequency was discontinued on charts years ago. He agreed that further training and reporting of proper frequencies to use outside controlled airspace is important and will pursue the matter.

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Original NASA ASRS Text

Title: Helicopter pilot reported taking evasive action to avoid a NMAC with another helicopter. Reporter was utilizing the current published frequency; while the other Helicopter was possibly utilizing outdated frequency information.

Narrative: I had passengers loaded on Helicopter X. After receiving the thumbs up from the ramper; I made a radio call on CTAF; indicating I was lifting to the south. Approaching Queens Gate and leveling off at 500'; I made another radio call; indicating Helicopter X at Queens Gate southbound. I noticed a traffic indication on my GPS showing a target very close and 100' below. I looked around but did not see anything. Within about 3 seconds; I saw Helicopter Y to my left and slightly lower; traveling at a high speed west bound from left to right. I immediately performed a cyclic climbing evasive maneuver to avoid his rotor disc; missing the aircraft by only about 10-20 feet. I tried to call the other helicopter several times but received no response. He or she apparently did not see me at all; as they took no evasive action.[An individual] from the base called me to discuss the matter. He indicated no violation could occur; as this was uncontrolled airspace. I informed him that this is a busy area and aircraft should be announcing positions and intentions as indicated on the appropriate aeronautical charts. He told me they use [a different frequency]; which is on the sectional charts. I have been informed that that frequency was discontinued on charts years ago. He agreed that further training and reporting of proper frequencies to use outside controlled airspace is important and will pursue the matter.

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.