AS350 check airman was notified after a night vision goggles training flight that tail rotor damage ...

Narrative:

I was conducting an nvg training session and check ride. The next morning I was notified that there was tail rotor damage to the aircraft. I began dissecting the flight to determine how the damage could have occurred. I drove to the airport and inspected the damage to the tail rotor. I decided that the damage must have occurred while I was evaluating the steep approach to a confined area landing into the training site. The landing sequence was normal and there was no abnormal control feedback for the duration of the flight at the completion of the maneuver. I did not detect any damage during the post flight inspection even having rotated the rotor blade from the tail rotor for hangar spacing. I proceeded to the training site to determine if I could find the impact source to the tail rotor. I found an 8 foot sapling that showed 'trimming' on one side in the approximate area that we had landed. The largest part of the strike looked to be just smaller than the diameter of my thumb but we could have very easily been into the thicker part of the tree. I was familiar with the lz and routinely conducted training operations there. The pilot on the controls was not familiar with the lz. Weather; illumination and lz condition were not a factor in this incident. The deviation to the specific landing touchdown area was minimal but resulted in contact with a sapling standing approximately 8 feet in height. The angle of approach appeared to insure clearance to the intended touchdown area but the visual limitations of the helicopter and the difficulty seeing the dormant (for the winter) 8 foot sapling directly resulted in the impact and subsequent damage to the tail rotor. Again; there was no abnormal feedback through the controls that a strike had occurred and post flight did not indicate obvious damage. Performing a clearing turn would not have been recommended in this case due to the confines of the lz. Instructing the pilot on the controls to a specific 'safe' landing touchdown would be an acceptable solution. The actual touchdown area is relatively safe except for the 8 foot sapling that neither pilot saw.

Original NASA ASRS Text

Title: AS350 Check Airman was notified after a Night Vision Goggles training flight that tail rotor damage was detected. Check Airman returned to the area where training had been conducted and found evidence of a tail rotor strike on an eight foot sapling.

Narrative: I was conducting an NVG training session and check ride. The next morning I was notified that there was tail rotor damage to the aircraft. I began dissecting the flight to determine how the damage could have occurred. I drove to the Airport and inspected the damage to the tail rotor. I decided that the damage must have occurred while I was evaluating the steep approach to a confined area landing into the training site. The landing sequence was normal and there was no abnormal control feedback for the duration of the flight at the completion of the maneuver. I did not detect any damage during the post flight inspection even having rotated the rotor blade from the tail rotor for hangar spacing. I proceeded to the training site to determine if I could find the impact source to the tail rotor. I found an 8 foot sapling that showed 'trimming' on one side in the approximate area that we had landed. The largest part of the strike looked to be just smaller than the diameter of my thumb but we could have very easily been into the thicker part of the tree. I was familiar with the LZ and routinely conducted training operations there. The Pilot on the controls was NOT familiar with the LZ. Weather; illumination and LZ condition were NOT a factor in this incident. The deviation to the specific landing touchdown area was minimal but resulted in contact with a sapling standing approximately 8 feet in height. The angle of approach appeared to insure clearance to the intended touchdown area but the visual limitations of the helicopter and the difficulty seeing the dormant (for the winter) 8 foot sapling directly resulted in the impact and subsequent damage to the tail rotor. Again; there was no abnormal feedback through the controls that a strike had occurred and post flight did not indicate obvious damage. Performing a clearing turn would NOT have been recommended in this case due to the confines of the LZ. Instructing the Pilot on the controls to a SPECIFIC 'safe' landing touchdown WOULD be an acceptable solution. The actual touchdown area is relatively safe EXCEPT for the 8 foot sapling that neither pilot saw.

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.

Attributes
ACN	1222739
Time
Date	201412
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Eurocopter AS 350/355/EC130 - Astar/Twinstar/Ecureuil
Operating Under FAR Part	Part 91
Flight Phase	Landing
Person 1
Function	Check Pilot Pilot Not Flying
Qualification	Flight Crew Commercial
Events
Anomaly	Aircraft Equipment Problem Less Severe Ground Event / Encounter Object Inflight Event / Encounter Object

AS350 check airman was notified after a night vision goggles training flight that tail rotor damage was detected. Check airman returned to the area where training had been conducted and found evidence of a tail rotor strike on an eight foot sapling.