AARO
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◉ 40.7° N · 81.4° W · Mansfield, Ohio · 18 Oct 1973

Coyne 1973

On the night of 18 October 1973, at approximately 23:05 local time, a U.S. Army Reserve UH-1H Iroquois helicopter from the 316th Medical Detachment was returning from Columbus to Cleveland Hopkins when its crew of four observed a brilliant red light approaching at high speed from the east. Capt. Lawrence Coyne placed the aircraft in a 500 ft/min descent from 2,500 ft toward 1,700 ft; the object continued closing, paced the helicopter briefly at close range, then departed westward at high speed. During the encounter the helicopter — without any pilot input — climbed back to 3,500 ft at 1,000 ft/min, contrary to its descent command. The case was documented by the U.S. Army, examined under the Condon Committee follow-up review, corroborated by ground witnesses near Mansfield, and is now referenced in AARO's 2024 Historical Record.

Aircraft: UH-1H Iroquois · 316 Med Detach · Cleveland
Crew: Capt. Lawrence Coyne · Lt. Arrigo Jezzi · SSgt. John Healey · Sgt. Robert Yanacsek
Authority: U.S. Army · later NARA · AARO HRR
Status: AARO HRR Vol. I — unresolved near-miss
Read time: 3 min · 717 words

The four-witness cockpit + ground corroboration

All four crew members — Coyne, Lt. Arrigo Jezzi (co-pilot), SSgt. John Healey, Sgt. Robert Yanacsek — gave sworn depositions to the U.S. Army within 48 hours of the event. Independent of the cockpit, five civilian witnesses in a car on Route 430 near Mansfield observed both the UH-1H and an unidentified red light pacing alongside it. The five — including 13-year-old Erica Roth, who later provided contemporaneous drawings — were located by civilian investigator Jennie Zeidman in 1976 and gave statements that match the cockpit account on all key parameters (timing, altitude, colour, departure direction).

The uncommanded climb

The single most-discussed element of the Coyne case is the uncommanded 1,000 ft/min climb. Coyne's deposition states he had placed the collective pitch lever in the full down (descent) position; during the encounter the aircraft climbed from 1,700 ft to 3,500 ft without any crew input, and the magnetic compass was observed rotating freely. The Federal Aviation Administration's Cleveland Hopkins control tower noted JANO 968's radar return throughout. Aerodynamic analysis by USAF retired Lt. Col. Wendelle Stevens + civilian engineer Jennie Zeidman concluded the climb cannot be accounted for by conventional aerodynamic, instrument, or pilot factors.

Why this case still matters

Coyne is the most thoroughly documented case of an uncommanded aerodynamic anomaly coincident with a UAP near-miss in the pre-AARO record. It is the only U.S. military case where: (1) all four cockpit witnesses gave sworn military depositions within 48 hours; (2) independent civilian ground witnesses corroborated within the same minute; (3) air-traffic-control radar logged the helicopter's anomalous flight profile; (4) the U.S. Army released the case file under the post-Condon administrative procedure. The American Institute of Aeronautics and Astronautics (AIAA) sub-committee on UAP examined the case in 1976 and rated it among the highest-confidence multi-witness aviation events in U.S. records.

The voice on the tape

I had the collective full down for a descent. The aircraft climbed against my input from 1,700 to 3,500 feet without any commanded change. The magnetic compass spun freely. We never recovered the cause. — Capt. Lawrence Coyne, U.S. Army Reserve deposition, 22 October 1973

Timeline

Linked evidence in this archive

Why this case still matters

Coyne is the canonical pre-modern example of a UAP near-miss coincident with an aerodynamic anomaly. It anchors AARO's modern 10 U.S.C. § 1683 doctrine that UAP attribution must consider not just sensor data but also unexplained airframe / instrumentation behaviour. The case combines all four desirable signatures — multiple military-pilot witnesses, ground witnesses, ATC radar, and physical instrument anomaly — in a single 90-second event.

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