On the second weekend of oct 2013 i had finished my daily run as a tanker driver and had returned to our yard. it was apx 1:15 to 1:30 am. i parked my truck and began a post trip inspection. i then climbed up the ladder to the top of the tanker placing me apx 12 off the ground and my added height appx 18 feet in the air..I vented my tank. while on top of the tank i looked southwest and observed 2 very bright lights as if they were on a plane,i also observed marker lights on both sides...Red. i thought this odd as planes have red n green.I thought that was unusual as it was the wrong approach for a plane going to our municipal airport...The "plane "continued to get larger as it got closer...In about 4-5 minutes i observed coming at me a giant triangle/with the large top triangle and a smaller triangle under the top,each being appx 3 stories tall@ 15 feet a story..The ship began to pass me overhead at appx a 60 degree above me angle and about 4-500 feet above..The sky was very bright and clear,appx 35-38 degrees..The sky/moonlight lit the craft up very well. as the craft was passing overhead i began to count,1000/1001/1002... up to 1007.7-8 seconds...During this time i saw body panels that had been shaped to form the ships structure,i could see the panels were butted together in sections but not how..Meaning i couldnt see welds or rivits..Only large panels,the craft was a silver metalic associated with aluminum/stainless,the crafts color was weathered and staining in a downward lines on the entire body,there were no windows anywhere on the length of the craft,there were 3 solid red lights on the craft at front middle and rear, the giant front "headlights" were fixtures hanging down and facing foward.They reminded me of the large hollywood lights that shine upward into the sky..The ship had no sound of a motor/propulsion,as the craft was passing only the sound of wind being displaced, no exhaust/outlet could be seen on the rear..Just quite...I estimated the craft to be 300 yards long by 200 yards wide,extremly huge,...As the craft continued to the north by northeast in appx 5-7 seconds i heard helicopters, but the normal sound of rotar wash was only half sound.Very stealthy...Two cobra heli's came into view,both appeared to be banking to fall in behind the ship,not a sharp bank but a gradual bank, the choppers were totally black,no markings/no numbers/visible armament could be seen/rocket pod /the flying lights were on and flashing..The closest chopper to me also at a 60 degree angle was very close above me.I could see the instrument lights reflecting on his windows,orange and bright green..I could make out his white helmet...In disbelief at what i had just seen and now seeing the choppers it seemed surreal....I waved.....The pilot waved back.....I was in shock...I watched the craft n choppers go thru a local mountain pass,the crafts width as it passed thru the pass had a very narrow margin to get thru as it was so big.. later on in talking with law enforcement officers on duty the same night,they told me they had seen the ship also and were driving towards my location to get a better view,so their sighting was at a different viewpoint..But comments were made to me of how huge the craft was.