Investigation Summary
The runway incursion was facilitated by a specific operational configuration at Springfield-Branson National Airport (SGF). Runway 14/32 was under a NOTAM closing it to arrivals to allow for mowing operations in the underrun area. Under SGF standard operating procedures, when a runway is closed to landing traffic, operational control can be transferred to the ground controller (GC) to facilitate runway crossings without requiring coordination with the local controller (LC). On the day of the incident, the GC held control of Runway 14. When the crew of ENY3660 requested Runway 14 for departure, the GC approved the taxi. However, when the aircraft reached the runway and reported ready, the LC issued a takeoff clearance without first coordinating with the GC to regain control of the runway. Simultaneously, the GC, acting within his authority over the 'inactive' runway, cleared an airport operations vehicle (VAN7) to cross. Surveillance video showed the aircraft passing through the intersection of Runway 14 and Taxiway U just three seconds after the vehicle had cleared the southwest edge of the runway, while the vehicle was still within the Runway Safety Area (RSA).
Final Conclusions
The National Transportation Safety Board determined the probable cause of the incident to be the local controller's failure to follow established facility directives by issuing a takeoff clearance for a runway that was not under his operational control. The investigation highlighted a breakdown in coordination between the local and ground control positions during a period where standard runway ownership had been modified by a NOTAM.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Systems & Failure Modes
Runway Incursion Device (RID)
A memory aid tool consisting of red push buttons that flash when activated to indicate a runway is occupied or closed. At SGF, the RID provides an aural 'check runway' alert when the push-to-talk button is pressed if the system is active.
Standard Operating Procedures (SOP)
SGF 7110.2I required the LC to coordinate with the GC before clearing aircraft on a runway not designated as active, and to use the RID as a visual alarm for inactive runways.
Interesting Facts
- 01Runway 14 was NOTAM'd closed for arrivals but available for departures due to mowing in the safety area.
- 02The aircraft passed the intersection of Taxiway U approximately 3 seconds after the vehicle cleared the runway edge.
- 03The distance from the runway threshold to the intersection where the incursion occurred was approximately 5,900 feet.
- 04The airport was not equipped with ground-based radar (ASDE-X or similar) to assist controllers with surface surveillance.
- 05The local controller involved was a trainee qualified on ground control but still training for the local control position.
Safety Actions & Advisories
Reinforcement of RID Usage
Source ↗Following the incident, the FAA reinforced the requirement for controllers to use the Runway Incursion Device (RID) as a visual and aural memory aid when a runway is closed or under the control of a different position.
ATC Coordination Procedures
Source ↗The facility emphasized adherence to SGF 7110.2I, which mandates that the Local Controller must coordinate with the Ground Controller to regain operational control of a runway before issuing takeoff clearances if the runway was previously transferred to Ground Control.
Location
NO VERIFIED COORDINATES · This position predates coordinate provenance tracking. Treat it as an approximate marker for the area, not the accident site. No map is shown, because a marker here would imply a precision the record does not have.
Reported location: Springfield, Missouri, United States