Comair B734 at Johannesburg on Jul 27th 2012, cleared to cross runway despite runway occupied for takeoff
Last Update: August 23, 2012 / 14:16:26 GMT/Zulu time
Incident Facts
Date of incident
Jul 27, 2012
Classification
Report
Airline
Comair
Flight number
MN-102
Departure
Cape Town, South Africa
Destination
Johannesburg, South Africa
Aircraft Registration
ZS-OAO
Aircraft Type
Boeing 737-400
ICAO Type Designator
B734
A South African Airways Boeing 737-800, registration ZS-SJS performing flight SA-327 from Johannesburg to Cape Town (South Africa) with 124 passengers and 6 crew, had been cleared for takeoff from runway 21R while still taxiing on taxiway A and was entering the runway via taxiway N.
When MN-102 reported on Tower West frequency about one minute after takeoff clearance to SA-327 had been transmitted, the controller cleared the aircraft to cross runway 21R. When the aircraft reached the holding line L at runway 21R, the stop bars were still turned on. The crew queried the stop bars, tower turned them off and the aircraft began to taxi past the hold short line.
In the meantime SA-327 had aligned with the runway center line and was beginning its takeoff roll.
The west controller realised his error at that point, cancelled the takeoff clearance and instructed SA-327 to stop immediately. The aircraft had acclerated to about 80 knots indicated airspeed when the crew rejected takeoff and brought the aircraft to a safe stop. The controller apologised, instructed SA-327 to vacate the runway to the right and return to the holding point.
SA-327 successfully departed on their second takeoff run and reached Cape Town without further incident for a safe landing.
The crew MN-102 first heard of the presence of SA-327 when the controller cancelled the takeoff clearance. The aircraft safely crossed runway 21R and reached the apron.
South Africa's Civil Aviation Authority (SACAA) released their final report concluding the probable cause of the serious incident was:
Rejected takeoff due to runway incursion.
Contributory Factor
Error caused by ATC when giving instructions to one aircraft to cross the active runway after takeoff clearance was given to another aircraft, using the same runway.
The SACAA reported that a student air traffic controller under the supervision of an instructor air traffic controller was at duty at Tower West at the time of the incident. Both student and instructor had taken their positions 20 minutes prior to the incident and were immediately relieved from duty following the incident.
The student controller had been involved in two other incidents in February and March 2010 while undergoing training for approach control. As a result air traffic services had suspended his training on approach, but permitted his training as tower controller to continue.
Weather conditions at the time of the occurrence were "severe clear" at temperatures around 16 degrees C.
SA-327 had been issued takeoff clearance while taxiing on taxiway A still 1445 meters from taxiway N, the aircraft needed 127 seconds until it reached the runway following the takeoff clearance and immediately began their takeoff roll.
MN-102 reported on west frequency 51 seconds after the takeoff clearance and was cleared to cross runway 21R 73 seconds after the takeoff. The aircraft was 200 meters from the holding point L at that time and needed 103 seconds until reaching the holding point. The crew stopped seeing the stop bars still active, refused to cross the runway with the stop bars active and queried the tower, upon receiving that query the tower controller realised he had not turned off the stop bars when issuing the crossing clearance and just turned the stop bars off. MN-102 then continued to cross the runway.
SA-327 was not paying particular attention to the radio communication between tower and MN-102, they had realised the aircraft was holding short of the runway and thought, the flight was waiting for departure clearance. They did not expect any other traffic would use the runway after they had received takeoff clearance.
The SACAA further analysed that the sequence of events showed the controllers were not in control of the situation and continued: "It is the opinion of the investigator that the reason could be because of their behaviour displayed in the tower, which was complacency and over-confident. The result was inattention which is probably due to the undemanding environment as seen by the workload at the time. There was no threat of anything going wrong, which heightened a false sense of security within them. By the time that the threat of runway incursion was detected, it was almost too late because both aircraft were already on course to a collision on the runway." and later: "A disaster was imminent, that of having the two aircraft colliding, probably with the result of having a considerable number of occupants fatally or seriously injured." SA-327 had reached a speed between 80 and 90 knots, below V1, when the takeoff was rejected.
The SACAA further analysed with regards to the performance of the student controller and logs from his training: "The instructors had identified the problem to be the inability of the student to do the following; “sequence for rotation of strips, crossing cards, and stop bars co-ordination,” which were identified in the investigation as factors that contributed to the incident. It is the opinion of the investigator that the student was having a problem adapting to the ATC operational requirements of FAJS. During the few weeks when he was doing practical training in the tower, week after week the same result of poor performance was noted. The student was not improving on the identified items until the incident occurred."
Incident Facts
Date of incident
Jul 27, 2012
Classification
Report
Airline
Comair
Flight number
MN-102
Departure
Cape Town, South Africa
Destination
Johannesburg, South Africa
Aircraft Registration
ZS-OAO
Aircraft Type
Boeing 737-400
ICAO Type Designator
B734
This article is published under license from Avherald.com. © of text by Avherald.com.
Article source
You can read 2 more free articles without a subscription.
Subscribe now and continue reading without any limits!
Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.
Send tip
Support AeroInside by sending a small tip amount.
Related articles
Comair B738 at Johannesburg on Apr 19th 2022, possible tail scrape on departure
A Comair Boeing 737-800, registration ZS-ZWY performing flight MN-399/BA-6399 from Johannesburg (South Africa) to Mauritius (Mauritius) with 152…
Fleet type match
Comair B734 at East London on Feb 20th 2022, could not retract landing gear
A Comair Boeing 737-400, registration ZS-OTG performing flight MN-252 from East London to Johannesburg (South Africa) with 111 people on board, was…
Fleet type match
Comair B738 at Johannesburg on Dec 16th 2019, cabin did not pressurize
A Comair Boeing 737-800, registration ZS-ZWT performing flight MN-601 from Johannesburg to Durban (South Africa) with 183 passengers and 6 crew, was…
Fleet type match
Comair B738 near Lanseria on Jul 8th 2019, engine shut down in flight
A Comair Boeing 737-800, registration ZS-ZWE performing flight MN-494 from Cape Town to Lanseria (South Africa) with 182 passengers and 6 crew, was…
Comair B738 at Johannesburg and Durban on Apr 19th 2019, aircraft operated the flight with elevator damage following ground collision
A Comair Boeing 737-800, registration ZS-ZWV performing flight MN-219 from Johannesburg to Durban (South Africa) with 131 passengers and 7 crew, was…
Newest articles
THY A321 and SunExpress B738 over Skopje on Sep 7th 2024, TCAS at the rescue
A THY Turkish Airlines Airbus A321-200, registration TC-LPB performing flight TK-1358 from Madrid,SP (Spain) to Istanbul (Turkey), was enroute at…
Fleet type match
KLM Cityhopper E175 at Dublin on Oct 19th 2022, first officer incapacitated
A KLM Cityhopper Embraer ERJ-175, registration PH-EXI performing flight KL-934 from Dublin (Ireland) to Amsterdam (Netherlands), was climbing out of…
Subscribe today
Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.
Pick your plan and subscribePartner
A new way to document and demonstrate airworthiness compliance and aircraft value. Find out more.
ELITE Simulation Solutions is a leading global provider of Flight Simulation Training Devices, IFR training software as well as flight controls and related services. Find out more.
Your regulation partner, specialists in aviation safety and compliance; providing training, auditing, and consultancy services. Find out more.
AeroInside Blog
Popular aircraft
Airbus A320Boeing 737-800
Boeing 737-800 MAX
Popular airlines
American AirlinesUnited
Delta
Air Canada
Lufthansa
British Airways