Two brothers observe cigar-shaped UFO late at night after work.

Two brothers were headed home from work and spotted a very large hovering craft above a field.  They stopped and got out of the vehicle and observed said craft for at least 15 minutes.  The craft was emitted a low-pitched hum with a reverberating tone to it.  There were no lights on the object.  The object then began to emit a louder humming tone and began to tilt from a horizontal position to a vertical position.  Then the object lifted up and out of sight in a very rapid fashion.  There was no wind, no heat, no radiation burns, no known magnetic effects, no effect on the vehicle or any other objects around the vicinity.  The two brothers were excited but frightened by the experience.  They returned home and  woke up everyone to inform them of what they had just experienced.  They have subsequently re-told this story in identical fashion for years and have never had any other comparable experience.
Witness elects to remain totally anonymous; provides little contact information.  PD