AN ACR CREW TAXIING AT NIGHT USING CTRLINE TAXI LIGHTS EXPECTS RWY CTRLINE LIGHTS ON THE RWY. WITH THIS EXPECTATION THEY LINE UP ON THE RWY EDGE LIGHTS IN ERROR UNTIL NOTICING THAT THE LIGHTS LEFT SHADOWS WHEN LNDG LIGHTS WERE TURNED ON DURING START OF TKOF. A LOW SPD ABORT IS THE RESULT.
Synopsis
AN ACR CREW TAXIING AT NIGHT USING CTRLINE TAXI LIGHTS EXPECTS RWY CTRLINE LIGHTS ON THE RWY. WITH THIS EXPECTATION THEY LINE UP ON THE RWY EDGE LIGHTS IN ERROR UNTIL NOTICING THAT THE LIGHTS LEFT SHADOWS WHEN LNDG LIGHTS WERE TURNED ON DURING START OF TKOF. A LOW SPD ABORT IS THE RESULT.
Narrative
TAXI OUT OF INTL TERMINAL AT LAS. ONE FOLLOWS THE GREEN TAXI CTRLINE LIGHTS; FOR ABOUT 20 MINS; TILL AT THE DEP END OF RWY 25R. WHEN TURNING ONTO RWY 25R; I LINED UP ON THE RWY EDGE LIGHTS; THINKING I WAS ON THE CTRLINE LIGHTS OF RWY 25R. STARTED TKOF ROLL. AFTER 30 FT OF MOVEMENT; I REALIZED I WAS NOT ALIGNED ON THE RWY AND TURNED TO CTR OF RWY AND CONTINUED THE TKOF. THIS IS THE FIRST TIME I HAVE SEEN AN OPTICAL ILLUSION OR HEARD OF ONE LIKE THIS. THE CTRLINE LIGHTS AT RWY 25R WERE OFF. THE LONG TAXI ON TAXI CTRLINE LIGHTS; THEN TURNING ONTO RWY CAUSES AN OPTICAL ILLUSION THAT MAKES YOU LINE UP ON THE RWY EDGE LIGHTS; THINKING YOU ARE ON THE RWY CTRLINE LIGHTS. THE RWY CTRLINE LIGHTS SHOULD BE ON AT NIGHT AT ALL TIMES. NO CONFLICT OR EVENT OCCURRED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR SAID THAT THE EXTENDED TIME TAXIING WITH ONLY REF TO TAXI LIGHTS IN THE CTR OF THE TXWY LED THEM TO ASSUME THEY WOULD BE LED ONTO THE RWY BY CTRLINE LIGHTS. THE ILLUSION WAS THAT THE GREEN TXWY CTRLINE LIGHTS LED TO THE EXPECTED WHITE RWY CTRLINE LIGHTS. THERE ARE NO BLUE TXWY EDGE LIGHTS AT LAS. HE; AS THE TAXIING PLT; LINED UP ON THE WHITE LIGHTS THAT WERE IN FACT THE EDGE LIGHTS. THE FO; AS THE PF; NOTICED THE SHADOWS CREATED WHEN THE LNDG LIGHTS WERE TURNED ON FOR TKOF; ABORTED THE TKOF AND REALIGNED THE ACFT WITH THE PAINTED CTRLINE.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.