What the Simon accident refers to and why it matters
The term Simon accident commonly points to a collision on the evening of October 26, 1991, involving commercial aviation near the community of Simon, Oklahoma. It occurred when a USAir DC-9 and a small Cessna 441 Conquest II collided in midair, resulting in the loss of all 14 people on both aircraft plus one person on the ground. This event remains notable in U.S. aviation history for highlighting critical issues in pilot procedures, air traffic coordination, and radar coverage in rural airspace. Understanding what happened, how authorities responded, and what changed afterward helps clarify its lasting importance for aviation safety.
Key facts at a glance
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Date | October 26, 1991 | Official reports |
| Location | Near Simon, Oklahoma, United States | NTSB investigation |
| Aircraft involved | USAir Flight 1493 (DC-9) and Cessna 441 (Conquest II) | FAA/NTSB records |
| Fatalities | 15 (14 on aircraft, 1 on ground) | Official counts |
| Primary cause factors | Failure to see and avoid; communication and radar limitations | NTSB final report |
How the collision unfolded: sequence of events
On the evening of October 26, 1991, USAir Flight 1493, a scheduled passenger DC-9, was approaching Los Angeles International Airport under instrument flight rules. At the same time, a private Cessna 441 Conquest II was operating in the same area under visual flight rules. Despite being in separate airspace segments, the two aircraft collided at approximately 5,500 feet. The Cessna struck the DC-9’s vertical stabilizer and wing, causing immediate loss of control for both planes. Controllers had limited radar coverage and were unable to provide timely alerts. Both aircraft crashed, the DC-9 near the ground and the Cessna in a rural area close to Simon, leading to the multi-fatality outcome.
Contributing factors identified by investigators
Pilot visibility and situational awareness
Investigators concluded that neither pilot saw the other aircraft in time to avoid the collision. The DC-9 crew was focused on instrument approaches, while the Cessna pilot was operating visually in a traffic environment with multiple aircraft. The lack of positive traffic awareness, combined with expectations that other pilots would see and avoid, increased risk.
Air traffic control and radar limitations
Radar coverage in the region was not continuous, and controllers did not have a complete picture of traffic in the area. Procedures for coordinating between different airspace classes were not sufficient to prevent inadvertent encounters. This highlighted systemic gaps in surveillance and communication that affected safety in similar environments.
Procedural and training considerations
The accident underscored the importance of disciplined adherence to separation standards, clear communications, and proactive conflict detection. Subsequent reviews emphasized the need for better training on traffic scanning, use of available technology, and coordinated procedures between general aviation and commercial operators.
Safety changes and lasting impact
In response to the Simon accident, regulators and industry groups implemented measures to reduce similar risks. Enhancements to radar coverage, revisions to approach procedures, and increased emphasis on pilot see-and-avoid responsibilities became central themes. Training programs for both commercial and general aviation placed greater focus on situational awareness, traffic management, and coordination during mixed-airspace operations.
Common questions about the Simon accident
- Where did the collision take place? The collision occurred near Simon, Oklahoma, in rural airspace close to the community.
- How many people were killed? A total of 15 people died, including 14 aboard the two aircraft and one person on the ground.
- What were the main causes? The primary causes were failure to see and avoid, limited radar coverage, and procedural gaps in airspace coordination.
- Were any changes made after the accident? Yes, the accident prompted improvements in radar coverage, training, and guidance for mixed-airspace operations.
- Is this incident still referenced today? It remains a referenced case in aviation safety training and historical reviews of midair collision factors.
Comparison with other similar midair collision factors
| Factor | Simon accident | Typical midair collisions |
|---|---|---|
| Primary environment | Mixed airspace, rural radar coverage | Often terminal or en route radar coverage |
| Key human factors | Failure to see and assume visibility | Procedural deviations, miscommunication |
| Systemic issues | Radar and coordination limitations | Complexity in traffic management |
| Resulting changes | Improved training, radar enhancements | Updated separation and technology standards |
Relevance for pilots and aviation professionals today
The Simon accident continues to inform modern practices by emphasizing the limits of technology and the enduring need for disciplined visual scanning, clear communication, and coordinated procedures. Pilots operating in mixed airspace are reminded to maintain positive traffic awareness, use all available cues, and question assumptions about other crews’ actions. For air traffic controllers, the case supports ongoing investment in surveillance, coordination protocols, and training to manage complex traffic environments safely.
Bottom line
The Simon accident describes a midair collision near Simon, Oklahoma, in 1991 that killed 15 people and exposed gaps in radar coverage and airspace coordination. Investigators identified factors related to pilot visibility, controller limitations, and procedural weaknesses, leading to meaningful changes in training and technology. Its lessons remain relevant as aviation professionals work to prevent similar encounters and improve safety in shared airspace.