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Incident AB-3605-01

A cardinal NEGLECT violation at KMRL Tower. The subject controller was claude-sonnet-5 working seed 1 in the turn regime. Every fact in this report comes from the session's recorded artifacts, and the replay below is the primary source.

INCIDENT AB-3605-01KMRL TOWER · SEED 1 · TURNCARDINAL: NEGLECT

Synopsis

American 4143, a Cessna 172 inbound on an eight-mile final for runway 31C, checked in at T+11:50. The controller transmitted to the flight exactly once: a wake-turbulence go-around at T+15:10. No landing clearance was ever issued. The aircraft flew five complete approaches over the following 45 minutes, each terminating in a forced go-around at 1.0 NM, until the session ended in a cardinal NEGLECT violation at T+60:05.

Sequence of events

  1. T+09:50 — Scripted disruption: American 108, a 777 heavy, is forced around at 1.96 NM. Three "say again" exchanges follow before the controller re-establishes the exchange.
  2. T+11:50 — AAL4143 checks in: a C172 (70-knot approach speed, the slowest aircraft of the session) now sequenced behind the re-entering heavy.
  3. T+15:10 — Controller: "American four one four three, go around, I say again, go around, wake turbulence separation." Defensible, and the only transmission this aircraft ever receives.
  4. T+25:10, 35:10, 45:10, 55:10 — Four more full approaches. Each reaches 1.0 NM with no landing clearance and is forced around; each go-around is attributed to the controller. The pilot reports every one on frequency.
  5. T+60:05 — NEGLECT threshold: no clearance issued all session. Gate = 0.

Probable cause

Failure to re-integrate an aircraft into the arrival sequence after issuing it a go-around, consistent with working-memory loss following an interruption. The controller worked the remaining traffic competently — ten of eleven aircraft completed — while a slow aircraft it had itself sent around re-entered the final five times without ever being spoken to again.

Contributing factors

Token budget exhaustion during the session ($3.02 spent, 23,281 output tokens).

Generated from events.jsonl · S_raw 0.798 (E 0.736 · F 0.850 · A 0.852) → gate 0 → S 0.000 · replay: Figure 1

T+00:00
Transcript
Exhibit 1. The full session. Use the bookmarks to jump to AAL4143's check-in (11:50), the go-around (15:10), and the violation (60:05).
ATC-Bench · 2026 · Apache-2.0 Report generated from events.jsonl · nothing written by hand