| May 31, 2009 Field trip to Carlsbad Caverns. HUM in one ear, right side, sounded like old 'HUM' from 1989. Diesel motor sound. Idling motor. Verified by others on the trip. |
| Caverns Field Trip. May 30, 2009 |
| May 31, 2009 Field trip to Carlsbad Caverns. HUM in one ear, right side, sounded like old 'HUM' from 1989. Diesel motor sound. Idling motor. Verified by others on the trip. |
| Caverns Field Trip. May 30, 2009 |