# NTSB Accident DCA20LA047
> **BOEING 737-824** · 2019-12-23 · Denver, CO, USA · NONE
## Event
- **NTSB number:** DCA20LA047
- **Event ID:** 20200107X35017
- **Type:** Accident
- **Date:** 2019-12-23
- **Location:** Denver, CO, USA
- **Coordinates:** 39.749443, -105.000801
## Injuries
- **Highest injury:** NONE
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 181
- **Total aboard:** 181
## Aircraft
- **Make:** BOEING
- **Model:** 737-824
- **Registration:** N87513
- **FAR Part:** 121
- **Engines:** 2
- **Damage:** SUBS
## Conditions
- **Light:** NITE
- **Weather:** VMC
## Probable cause

Maintenance personnel’s excessive grinding of the left main landing gear’s aft trunnion pin during its initial overhaul, which caused heat damage to the base metal and led to the fatigue crack that caused the pin to fail during the accident flight. Contributing to the accident was the failure of maintenance personnel to detect the excessive grinding during the initial overhaul and the fatigue crack during the subsequent overhaul.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=DCA20LA047) · AI Analytics · CC0 1.0*