At 0347 Pacific time, a Piper PA-28R-200 was damaged after it collided with a power line while attempting to land at Whiteman Airport in Pacoima, Los Angeles County. The pilot was seriously injured. The flight had departed the same airport approximately 17 minutes earlier. The airport lights were illuminated at that time. The pilot noted that the lights were still on while he was about 10 miles out on his return flight, but by the time he reached the airport only the taxiway lights were illuminated. The aircraft struck a power line when the pilot applied power to depart after unsuccessfully searching for the threshold with his landing light. Whiteman Airport does not have pilot-controlled lighting. Power lines are noted in the A/FD entry for Whiteman Airport.