A plane crash that killed four people who were working on improvements at Dubai International Airport was caused by the pilot following larger aircraft too closely.
A preliminary investigation into the accident by the United Arab Emirates’ General Civil Aviation Authority, found the Diamond DA62 twin-propeller aircraft lost control as it followed a Thai Airways A350-900 at a distance of 3.7 nm (nautical miles).
The A350 was flying the approach to the parallel runway 30R. The report said the four-seater DA-62 "rolled slightly" but was recovered after nine seconds. Seven seconds later the aircraft "abruptly rolled to the left until it became inverted and it then entered a steep drive".
The aircraft crashed about 5km south of the airport on May 16. Three Brits and a South African, who was employed by Kent-based Flight Calibration Services, were killed in the crash.
The aircraft, operated by a third party engaged by US tech giant Honeywell, was carrying out aerodrome ground lighting calibration checks as part of the southern runway refurbishment project. This required a number of approaches to, and low passes over, runway 30L, and began after meetings between the crew, air traffic control and airport representatives.
It was on the tenth approach that disaster struck, just before 7.30pm. Due to the aircraft weight category, it was not required to be fitted with a cockpit voice recorder or flight data recorder.
Minimum safe distance
The report said: “Observations of previous approaches during the same calibration flight indicated that the DA62 consistently followed preceding traffic on approach to the parallel runway 30R at distances which were below the specified minimum separation, and less than the distances discussed during the pre-departure meeting.
“The radar monitor recording indicated that there was an air traffic control (ATC) inconsistency in advising the DA62 of the expected occurrence of hazards caused by wake turbulence from traffic on approach to the parallel runway 30R.
“Based on these observations, the Investigation believes that there is sufficient reason to issue a prompt safety recommendation to re-emphasise to pilots and air traffic controllers the importance of maintaining a minimum safe distance and issuing essential traffic information such as advising aircraft of the expected occurrence of hazards caused by wake turbulence.”
As a result of the accident, Flight Calibrations Services has contacted all company pilots to raise their awareness of minimum separation criteria as detailed in a Eurocontrol document titled ‘European Wake Turbulence Categorisation and Separation Minima on Approach and Departure’.
A training course on wake turbulence effects during take-off and landing and a practical upset recovery training is also being developed. While Flight Calibrations Services is in the process of reviewing the procedures and processes for calibration flights.
Source: Arabian Business