INVESTIGATORS said that the helicopter which smashed into the Clutha pub had developed 256 faults in its last 32 flights.

A maintenance log contained in the Air Accidents Investigation Branch (AAIB) report reveals a catalogue of problems had plagued the aircraft's fuel contents indication system in the months before the crash.

The helicopter’s onboard systems clocked up an average of eight fault warnings per flight, although none were blamed for causing the disaster

Faults were initially identified on the helicopter’s display panel for the day it crashed on the the popular riverside pub in Glasgow.

However, this defect was discounted in the final report because the authors concluded it was triggered as the aircraft fell out of the sky rather than before power was lost.

But the report revealed other errors. On one occasion, the month before the crash, the maintenance log for the aircraft stated that indicators showed fuel was present when the tank was empty.

Another entry from the log read: “No 1 supply tank indications failed.” On several occasions, sensors were removed by mechanics and replaced with “serviceable parts” in an effort to solve problems.

On October 10, the month before the crash, another problem with the fuel supply indication system was identified.

A log entry was made stating: “No 1 supply tank indications failed with F QTY FAIL caption.” Work took place the next day when the No 1 supply tank sensor was replaced.

Further work was also recorded with the main fuel tank aft contents sensor being replaced with a “serviceable item” for fault diagnosis.