Definition
A computer model used by the FAA and aviation planners to estimate runway-related delays at an airport based on factors such as traffic volume, runway configuration, weather, and arrival/departure mix. It is used to study capacity, plan improvements, and predict how operational changes will affect delay times.
Plain English
A software tool that predicts how much delay an airport's runways will produce under different conditions. Planners use it to test 'what if' scenarios before making real changes.
Context Anchor
Seen in FAA acronym lists and airport planning material, not as a normal cockpit command or radio instruction.
Derivation
A simple compression of 'Runway Delay SIMulation.' 'Simulation' comes from the Latin simulare, meaning to imitate or model — useful here because the tool imitates real runway operations on a computer to see what would happen.
Why Pilots Care
Pilots rarely use RDSIM directly, but its outputs shape the runway configurations, scheduling, and capacity decisions that drive the delays pilots actually experience.
Intuition Check
Do not read RDSIM as a runway status or a clearance. It names a planning tool used to estimate delay, not an instruction to pilots.
Example Sentence 1
The airport authority used RDSIM to estimate how much a new parallel runway would reduce average departure delays.
Example Sentence 2
The RDSIM output helped decide whether an extra taxiway would cut average runway waiting time.