# NTSB Incident ENG18IA036
> **Boeing 757** · 2018-09-06 · Atlanta, GA, USA · NONE
## Event
- **NTSB number:** ENG18IA036
- **Event ID:** 20180913X21320
- **Type:** Incident
- **Date:** 2018-09-06
- **Location:** Atlanta, GA, USA
- **Coordinates:** 33.750141, -84.389007
## Injuries
- **Highest injury:** NONE
- **Fatal:** 0
- **Serious:** 0
- **Minor:** 0
- **Uninjured:** 0
- **Total aboard:** 0
## Aircraft
- **Make:** Boeing
- **Model:** 757
- **Registration:** N668DN
- **FAR Part:** 121
- **Engines:** 2
- **Damage:** MINR
## Conditions
- **Light:** NR
- **Weather:** Unk
## Probable cause

A right engine turbine uncontainment resulting from failure of the high pressure turbine (HPT) lenticular seal due to a fatigue crack originating from an overheated region at a knife edge tip.  Contributing to the failure was Pratt & Whitney’s decision to introduce the temperature-resistant knife-edge coating as a new-part number lenticular seal on an attrition basis without the option to recoat existing lenticular seals, which delayed implementation of the more durable seal material into the fleet.

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*Source: [NTSB CAROL](https://data.ntsb.gov/carol-main-public/basic-search?source=ntsb&type=event&ntsb_number=ENG18IA036) · AI Analytics · CC0 1.0*