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EXHIBIT 090 · TRANSPORTATION

Southwest 1380: a fragment escaped containment

A fan-blade fracture caused engine and inlet damage; debris struck the fuselage and a cabin window.

OrganizationSouthwest Airlines / engine and aircraft manufacturers
Period2018
LocationUnited States
StatusInvestigated
ImpactCritical
EvidenceOfficial investigation
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Illustrative draft · Source-backed synopsis · Museum analysis marked separately · Updated 5 October 2026

NTSB investigators inspect the damaged engine of Southwest Flight 1380 in Philadelphia on April 17, 2018.
NTSB investigators inspect the damaged engine of Southwest Flight 1380 in Philadelphia on April 17, 2018.National Transportation Safety Board / Wikimedia Commons. Resized. Photograph · Public domain · Resized for display.
01 / EXECUTIVE SUMMARY

The outcome is only the beginning.

A fan-blade fracture caused engine and inlet damage; debris struck the fuselage and a cabin window. [1]

THE PRINCIPLE TO CARRY FORWARD

Assess secondary structures and downstream debris paths under representative engine failures.

02 / THE PROMISE

What the system was trying to do.

Operate an aircraft with safe engine-failure containment.

Museum interpretation

The assumption beneath the promise

Museum hypothesis to examine: Containing the initial component failure also contains every secondary debris or dependency effect. This is an analytical proposition to test against the record, not an attributed statement by the organization.

Success should be assessed against the intended service and its safety, reliability, or integrity constraints. A headline outcome cannot tell us whether those constraints were visible, tested, or owned before the event.

03 / WHAT HAPPENED

A sequence, not a single moment.

The intended system

Operate an aircraft with safe engine-failure containment.

Source-backed synopsis

The event or review

A fan-blade fracture caused engine and inlet damage; debris struck the fuselage and a cabin window. [1]

Source-backed synopsis

The documented aftermath

NTSB issued inspection and design recommendations. [1]

Source-backed synopsis
Timeline of documented milestones. Gaps are not evidence that nothing happened. Sources: [1]
04 / WARNING SIGNS

What could be seen at the time?

Documented in cited record

NTSB examined fatigue-crack detection and the behavior of the inlet and fan cowl. [1]

Who could see it?

See the cited investigation for named teams and the information they held. The synopsis does not infer awareness by every stakeholder.

Why was it not enough?

Signals need interpretation, authority, and a route to action. This is an analytical question, not proof that a warning was deliberately ignored.

05 / KEY DECISIONS

Choices made within constraints.

Museum analysis: Certification needed to cover the full debris path, beyond the engine core alone.

Available alternatives

Pause, test, narrow the operating envelope, seek independent review, or build a recovery option. These are proposed analytical alternatives; feasibility at the time is not established.

Information available

NTSB examined fatigue-crack detection and the behavior of the inlet and fan cowl. [1]

Incentives & constraints

Delivery pressure, cost, authority, and incomplete knowledge may shape a decision. Their specific weight is not established by this synopsis.

Risk accepted

Ask whether the relevant risk was recognized, who had authority to accept it, and whether affected people understood its implications.

06 / SYSTEM MAP

How conditions connected.

Select a node to inspect its evidence. Links show a proposed analytical relationship, not a measured causal effect.

05 / External context04 / Warning signal03 / Decisions02 / Technical conditions01 / Trigger06 / Consequences
Triggering event

A fan-blade fracture caused engine and inlet damage; debris struck the fuselage and a cabin window. [1]

Legend: numbered nodes = analytical categories; dashed arrows = proposed influence or propagation. Museum interpretation informed by the sources below. Feedback and omitted influences require further investigation.
07 / CONSEQUENCES

Beyond the immediate event.

One passenger died and the flight made an emergency landing. [1]

Technical impactOperational impactHuman impact

Categories identify documented or relevant consequences. Financial, human, and environmental totals are not estimated here when the source base does not support them.

08 / WHAT THE MODELS EXPLAIN

More than one lens.

Analytical lens

Swiss Cheese Model

Harm can pass through gaps in multiple defenses: organizational influences, supervision, preconditions, and active failures.

In this case, use the lens to examine failure propagation. This application is museum interpretation, not a finding of the original investigation.

Limit: A useful lens, not proof of a universal linear cause. Barriers interact and change over time.

Analytical lens

FMEA

Identify failure modes, their effects, and controls before or during system development.

In this case, use the lens to examine failure propagation. This application is museum interpretation, not a finding of the original investigation.

Limit: Lists can miss interactions and unanticipated operating conditions; scores are not exact probabilities.

Analytical lens

Systems thinking

Examine relationships, boundaries, feedback, and incentives across a whole system.

In this case, use the lens to examine failure propagation. This application is museum interpretation, not a finding of the original investigation.

Limit: A broad lens needs explicit boundaries and evidence to avoid explaining everything after the fact.

09 / COUNTERFACTUALS

What could have changed the outcome?

Counterfactuals are hypotheses. They identify possible intervention points without claiming that a different choice would certainly have prevented the event.

INTERVENTION 2 / During early testing

Test the operating envelope

Exercise realistic boundary conditions and shared dependencies rather than validating components only in isolation.

Cost & feasibility

Requires time and independent review before commitment.

Likely effectiveness

May reduce exposure or consequences. Not quantified; feasibility and effect must be assessed against evidence available at the time.

10 / LESSONS

From hindsight to a usable practice.

FOR FOUNDERS

Assess secondary structures and downstream debris paths under representative engine failures.

Before accelerating hiring or spending, name the assumptions that remain untested and set evidence thresholds for the next commitment.

11 / AFTERWARD

Recovery is another investigation.

NTSB issued inspection and design recommendations. [1]

A corrective action is evidence of a response; it is not, by itself, evidence that the wider pattern has disappeared.

12 / SOURCES & EVIDENCE

Follow the record.

Documented claims are linked to sources. Analytical applications, lessons, and intervention proposals are museum interpretation. This draft does not establish motives or a single complete causal explanation.

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Editorial history & limits

Version 1 · 4 October 2026 — source-backed illustrative synopsis created. Independent editorial review is pending. No claim of exhaustive investigation. New sources may alter the analysis.