Narrative:

During taxi out from [the FBO] the aircraft's right main wheel; and subsequently the nose wheel; went off the prepared surface of the ramp/taxiway area and into the mud. I had received clearance to taxi to runway 35R via taxiway bravo. It was night; it had been raining heavily; and was raining lightly at the time. The ramp was wet and dark. I moved the aircraft out of the parking spot; (facing north) and turned to my right to head towards the taxiway. I found a solid yellow line; moving from west to east; which I took for the taxiway center line; and I followed it out to taxiway bravo. There were rain drops on my windshield; which reflected or refracted the blue taxiway lights; making it difficult to verify which blue lights were real and which were reflections or refractions. As I continued eastward toward taxiway bravo; the right main wheel left the pavement and entered the mud and sank; causing the aircraft to yaw to the right and the nose wheel to also depart the paved surface. I stopped the aircraft; shut down the engines; and notified ground control that I had run off the pavement and was in need of assistance. With the help of the airport personnel and the airport fire crew; we were able to dig the mud out from the front of the right main and tow the aircraft back onto the paved surface. The aircraft was examined and found to have no damage. Neither was there damage done to any property on the ground. It turns out the yellow line I took for the taxiway center line was actually a white solid line; painted to mark off a part of the ramp. I believe the causes of this occurrence were: the white line which was easily mistaken for a taxiway center line; the wet ramp; the water drops on the wind screen; and my failure to verify my location on the ramp.

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Original NASA ASRS Text

Title: An Eclipse 500 pilot taxiing from the FBO ramp at night in rain mistook a surface edge line for a taxiway centerline and ran the right main and nose gear off the prepared surface; stuck in the mud.

Narrative: During taxi out from [the FBO] the aircraft's right main wheel; and subsequently the nose wheel; went off the prepared surface of the ramp/taxiway area and into the mud. I had received clearance to taxi to runway 35R via taxiway Bravo. It was night; it had been raining heavily; and was raining lightly at the time. The ramp was wet and dark. I moved the aircraft out of the parking spot; (facing north) and turned to my right to head towards the taxiway. I found a solid yellow line; moving from west to east; which I took for the taxiway center line; and I followed it out to taxiway Bravo. There were rain drops on my windshield; which reflected or refracted the blue taxiway lights; making it difficult to verify which blue lights were real and which were reflections or refractions. As I continued eastward toward taxiway Bravo; the right main wheel left the pavement and entered the mud and sank; causing the aircraft to yaw to the right and the nose wheel to also depart the paved surface. I stopped the aircraft; shut down the engines; and notified ground control that I had run off the pavement and was in need of assistance. With the help of the airport personnel and the airport fire crew; we were able to dig the mud out from the front of the right main and tow the aircraft back onto the paved surface. The aircraft was examined and found to have no damage. Neither was there damage done to any property on the ground. It turns out the yellow line I took for the taxiway center line was actually a white solid line; painted to mark off a part of the ramp. I believe the causes of this occurrence were: The white line which was easily mistaken for a taxiway center line; the wet ramp; the water drops on the wind screen; and my failure to verify my location on the ramp.

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.