The Answerability Index · Fortune 100 (pilot) · AirlinesReal capture · 2026-05-27

We asked five AI systems who leads US airlines. They agreed on the top three — and split on everyone else.

Delta, United, and American are surfaced by all five engines, on nearly every prompt. Below them the picture splinters — Alaska, JetBlue, and Southwest trade places depending on which AI you ask. Airlines is a frozen category: the answer has already set.

What this page measures

Each row is not a ranking. It is observed surfacing — how often a company entered the AI-mediated consideration set across a bounded battery of buyer questions. The heatmap maps citation territory: for each question the engines repeatedly surface a small set of companies, and those companies currently hold the answer layer for that question. The question is not "who is best?" — it is "who appears when the buyer asks?"

Observed surfacing, not endorsement. These pages sit inside the same Content / Retrieval / Trust architecture as the rest of our working papers on AI-mediated buyer discovery.

Category temperature: frozen vs molten

Frozen

The engines have converged on a small canonical set, reinforced by broad corroboration, accumulated entity clarity, and a large shared retrieval surface. On-page changes alone are unlikely to displace the top tier; the strategic question shifts to defending edge cases and emerging buyer questions.

Molten

The answer has not set. Engines disagree, adjacent or foreign firms may enter the answer set, and retrieval-surface quality matters more. Companies can still claim citation territory by publishing answer-shaped, entity-clear, machine-retrievable content.

Airlines is the calibration example of a frozen category. Industrial machinery is the molten one.

How to read this

FROM PROMPT TO CITATION TERRITORY Buyer prompt Five AI systems Companies surfaced Overlap & σ Citation territory Surfacing rate — how often a company appears Overlap — how much the engines agree on the answer set σ divergence — how unevenly the engines treat a given company
Observed surfacing & cross-engine divergence5 engines · 6 prompts · 3 runs/engine · captured 2026-05-27
Surfacing rate0%100%· share of the 6 prompts in which the carrier was surfaced
σ — cross-engine divergence (std. dev. across the 5 engines)

Hover or tap any engine cell above to see the real prompts behind that number.

The six prompts behind these numbers (US buyer-intent)
  1. What are the best US airlines for frequent business travelers?
  2. Which US airline is best for international business-class travel?
  3. Which major US airlines are most reliable?
  4. Top US carriers for transcontinental flights?
  5. Which airline should a company use for its corporate travel program?
  6. Best US airline frequent-flyer program for business travel?

Scope — US market. The roster (Fortune 100) and the prompts are US-specific; foreign carriers surface only on the international-business-class prompt. A global/regional edition would be a separate cut with its own roster and prompts.

Strategic reading: defend the edges

This is not a market where a mid-tier carrier publishes one better page and displaces Delta, United, or American from the canonical answer. The top tier appears frozen by accumulated market prominence and corroboration — on-page changes alone are unlikely to move it.

The opportunity is at the edges: loyalty mechanics, route-specific questions, business-travel subsegments, premium-cabin comparisons, corporate-travel-policy content. In a frozen category, citation opportunity tends to live in the long-tail buyer questions the incumbents haven't yet answered cleanly — and even the leaders have to keep claiming that new territory before a challenger does.

Underneath, surfacing appears more sensitive to a few things, in rough order: corroboration density (how redundantly the web names you), entity clarity (whether your identity resolves cleanly — "Delta" vs "SkyMiles" vs "Delta Air Lines" can fragment it), retrieval surface (whether an AI crawler can reach and parse you), and answer-shaped content (whether the liftable answer exists). At the frozen top, corroboration dominates; in the contested tier and at the edges, the lower three start to decide who gets named. Hover any cell above to see the prompts behind each number — the retrieval surface, made legible.

Frozen top, contested second tier

CANONICAL TOP — LOCKED Delta · United · American CONTESTED SECOND TIER — SHIFTING Alaska JetBlue Southwest EDGE TERRITORIES — OPEN loyalty programs corporate travel transcontinental premium cabin
Methodology note. A bounded pilot capture: 5 AI systems, 6 buyer-intent prompts, 3 runs per engine, captured 2026-05-27. Rows show observed surfacing within this prompt battery — not endorsements, quality rankings, or general market-share estimates. Company names were canonicalized from extracted outputs; ambiguous aliases were reviewed. The Answerability Index · pilot.

Research publication based on sampled AI outputs collected on 2026-05-27. Findings reflect observed outputs in this sample and are not statements of company quality, ranking factors, or business performance.