DAT Danish Air Transport flight DX171 was an IFR domestic passenger flight from EKKA to Copenhagen Kastrup (EKCH).

4 crewmembers and 65 passengers were onboard.

During the pre-flight planning phase, the flight crew experienced difficulties with the combination of:

• Weather pre-flight planning (foggy weather within the area of the scheduled operation)
• A newly operator implemented electronic flight bag
• Operational flight planning back-up

At 05:15:20 hours, Kastrup tower instructed the flight crew of DAT Danish Air Transport flight DX171 to taxi to the holding point at runway 27L via taxiway E, and the aircraft was cleared to cross runway 27R.
The first officer read back the taxi instruction to Kastrup tower, and the commander repeated the taxi instruction to the first officer.
The aircraft departed the civil apron and started taxiing towards the holding point at runway 27L.

In order to line up the aircraft on, what the commander thought were, the runway centerline lights, the commander of DAT Danish Air Transport flight DX171 made a sharp right turn.

From time 05:20:03 hours until 05:20:24 hours, the first officer read the before take-off checklist with 13 challenge and response items.
A completion of the before take-off checklist included a runway heading and GPS alignment check, which was performed without remarks

While slowly taxiing on the underrun of runway 27L towards the threshold of runway 27L, the aircraft hit a runway edge light (red light) on the right-hand side of runway 27L.

During the initial take-off roll, the flight crew observed a thumping noise from the nose gear, and the commander realigned the nose gear slightly to the left, which was done to avoid the thumping noises caused by the nose gear hitting, what the flight crew thought, were the recessed runway centre line lights.

The right main gear hit elevated runway edge lights along the right-hand side of runway 27L.

When approaching the military arrester cable mechanism on the right-hand side of runway 27L, the commander of DAT Danish Air Transport flight DX171 realized that the aircraft was lined up on the runway edge lights along the right-hand side of runway 27L instead of the runway centreline lights of runway 27L.

At 05:20:48 hours, the commander aborted the take-off roll and manoeuvred the aircraft back to the centreline of the runway of runway 27L.

In darkness and hazy weather conditions, the flight crew lined up the aircraft on the runway edge lights along the right-hand side of runway 27L instead of the runway centreline lights of runway 27L.

This resulted in a misaligned take-off roll over the elevated runway edge lights along the right-hand side of runway 27L leading to damages to the runway edge lights and the aircraft itself.

A combination of environmental, operational, and human factors contributed to the sequence of events:

• Dark night operation
• Reduced visibility
• Runway and taxiway environment, including an extra tarmac width on runway 27L, the absence of runway shoulder markings, the absence of taxiway centreline lighting, and the use of a displaced threshold
• Flight crew divided attention unintentionally provoked by the before take-off procedures and checks
• Flight crew fatigue