Four Army Reserve aircrew reported an apparent collision threat near Mansfield, Ohio, on 18 October 1973. Captain Lawrence J. Coyne took the controls of their UH-1H helicopter and descended. The crew subsequently signed an Army report describing an unidentified object and an unexpected altitude gain. Their individual accounts provide different views of the event: the copilot's restricted sight line is particularly consequential when assessing claims of unanimous agreement on shape, green illumination and an externally induced climb.
Pilot in command, seated on the right and responsible for the evasive manoeuvre
Lawrence Coyne
Reported experience
The Army disposition form dated 23 November 1973 places helicopter 68-15444 near Mansfield at 11.05 pm, returning from Columbus to Cleveland. It records crew chief Robert Yanacsek calling attention to an eastern red light and subsequently reporting an apparent collision course. Coyne took the controls from copilot Arrigo Jezzi and descended from a reported 2,500 feet to 1,700 feet. The form says Mansfield Tower acknowledged their call but did not answer the aircraft query. It records a later 3,500-foot altitude and 1,000-foot-per-minute climb indication with the collective control fully down.
Coyne's description of shape and illumination was already public in the Plain Dealer on 21 October. The article attributed to him a cigar-shaped body, a steady red light and green illumination entering the cabin. In his statement to the United Nations Special Political Committee on 27 November 1978, he described a grey metallic body ahead of the helicopter and a green light turning into the windshield. He said the helicopter climbed while his controls and power remained set for descent. He specified altitude relative to mean sea level. His testimony preserves reported readings and control settings; no continuous flight-data trace accompanies the account.
Evidence review
Coyne had direct access to the controls and instruments, making his account central to the reported altitude anomaly. His division of attention between an apparent threat, the ground and the panel also matters. The exact point at which the descent became a climb was not observed continuously. The readings establish what he reported seeing; determining the cause requires the aircraft's motion and control sequence to be reconstructed.
The later UN statement preserved his account and proposal for international aviation reporting procedures. Grenada's representative explicitly introduced him as appearing in a private capacity. The record therefore documents a witness speaking before a UN committee, rather than an Army or United Nations determination of the object's nature.
Statement and reporting history
18–21 October 1973: the flight, reporting through aviation channels and early press description.
23 November 1973: the four crewmen attest to a common Army disposition report.
24 January 1974: Hynek interviews Coyne; the interview is later reproduced in Zeidman's monograph.
27 November 1978: Coyne addresses the UN Special Political Committee in a private capacity.
Signed document reproduced in Zeidman's Appendix A, PDF page 122, inspected as a scan. All four crew signatures visible. This is their attested report, not an independent Army finding identifying the object.
Original newspaper clipping reproduced at PDF page 123, inspected as a scan. John P. Coyne interviews the captain, identified in the article as his second cousin. Early public account; reported altitudes differ from the later Army form.
CUFOS monograph, March 1979. Printed pages 7–20 read in extracted text; selected scans checked, including interview chronology and later compass testimony. Reproduces the 24 January 1974 Hynek interview and later Zeidman interviews; original recordings not auditioned.
A/SPC/33/PV.35, partial verbatim record circulated 6 March 1979. Cover and PDF pages 23–28 inspected as scans. Grenada's introduction specifies Coyne's private capacity; this is an official record of later witness testimony.
Copilot Arrigo Jezzi, flight medic John Healey and crew chief Robert Yanacsek, whose views and duties differed
Coyne helicopter crew
Reported experience
Yanacsek, seated behind Coyne on the right, supplied the initial eastern-light warning. In testimony reproduced by investigator Jennie Zeidman, he described a solid oval outline and green illumination crossing the windshield and overhead glazing. He left open whether the light turned towards them or the helicopter moved through it. That distinction limits an inference of deliberate targeting from the apparent sweep alone.
Healey, the flight medic seated on the left, moved between the cockpit seats to observe. Zeidman reproduces an account recorded on 19 October in which he described a gun-metal-grey, cigar-shaped object with red, green and white lights and an apparent hesitation overhead. His estimated clearance was about 500 feet. In a December 1976 interview, he still described a green cone outside, but did not remember the cabin turning green, the light swivelling or the climb. An external green light and remembered green cabin illumination are therefore separate propositions.
Jezzi had been flying from the left seat before Coyne took over. In his 12 February 1977 interview, he said he could not see the approach to their right. He saw a bright white light moving away, without resolving a body, and did not see the green illumination or the reported hover. He remembered a subsequent altitude above 3,000 feet, possibly 3,500, but had not followed Coyne's controls and could not determine what caused the climb. His signature on the common report should be read alongside these explicit limits on personal observation.
Evidence review
The shared aircraft and communications gave the men overlapping experience while directing their attention differently. Their accounts preserve substantive differences in what each saw and later remembered. Zeidman's identified transcript places Healey's first recording within 18 hours of the flight. Her detailed Jezzi interview took place more than three years later. These collection dates matter when comparing immediate descriptions with later attempts to reconstruct the sequence. The original audio recordings were not auditioned in this review.
Jezzi considered conventional aircraft lighting but regarded the departing white light as unusually bright. He also recalled recurrent radio difficulties in the unit and uncertainty about the compass's earlier condition. These are observations and interpretations from a participating pilot. They require inclusion when evaluating the later claim that several systems failed together because of the object.
Statement and reporting history
19 October 1973: Healey records an account with a Cleveland police colleague, according to Zeidman's transcript provenance.
23 November–1 December 1973: the joint disposition form and Yanacsek's operational hazard form document the crew report.
1976–1977: later interviews preserve differences in illumination, viewing access and remembered instrument behaviour.
March 1979: CUFOS publishes Zeidman's investigation, incorporating testimony collected at different dates.
Signed document reproduced in Zeidman's Appendix A, PDF page 122, inspected as a scan. All four crew signatures visible. This is their attested report, not an independent Army finding identifying the object.
Reproduced DA Form 2396, PDF page 120, inspected as a scan. Describes the 18 October occurrence; signature date reads 1 December 1973. Range and proximity entries are witness estimates.
Printed pages 21–36 read; key passages inspected as scans. Identifies Healey's 19 October 1973 tape and December 1976 interview, and Jezzi's 12 February 1977 interview. Yanacsek's detailed interview has no explicit date at its opening.
Printed pages 77–86 read, with source-specific scan checks. Contains reported maintenance enquiries and the 2 April 1978 discussion. Technical interpretations are investigator and consultant positions; original maintenance records were not inspected.
Comparing the evidence
The Army disposition form records a common crew account of an operational hazard. It includes the altitude anomaly and an approach-speed estimate exceeding 600 knots, with no measured range or tracked target supplied. Detailed shape, green illumination and compass rotation are absent from the form. Shape and green cabin illumination were nevertheless reported in the Plain Dealer on 21 October. That article gives a lower minimum altitude and a different departure direction from the November form. The early publications establish that the detailed visual account was already circulating, while their differences limit a precise reconstruction of the flight.
The climb is the case's principal aircraft-response claim. The collective changes rotor-blade pitch; lowering it is normally part of initiating descent. Coyne reported finding it fully down while the helicopter climbed. Jezzi saw the later higher altitude but had not monitored the controls; he considered inadvertent movement or atmospheric lift as possible explanations. At a 2 April 1978 review, Zeidman raised the possibility of movement while Coyne leaned back. Yanacsek recalled him hunched forward instead. Zeidman ultimately interpreted the ascent as abnormal. Her conclusion draws on testimony and reconstruction: the inspected material supplies no continuous control record that would determine the force responsible for the climb.
The compass allegation has a later documentary history. Coyne told Zeidman that the magnetic compass rotated and was subsequently replaced, while the separate radio magnetic indicator remained steady. Jezzi recalled replacement and later trouble with the replacement compass; Coyne attributed that later trouble to faulty installation. Zeidman records that the maintenance documents could not be found and reports being told that minor instrument-change records were retained for only 60 days. Compass behaviour is therefore documented through later testimony, without a contemporaneous diagnostic record establishing a magnetic disturbance from the object.
The radio claim developed from a specific unanswered call into a broader account of interrupted communication. The November form records an initial acknowledgement followed by no answer to the traffic question. Coyne's later testimony describes repeated unsuccessful calls across radios and frequencies, although keying and channel-change tones remained audible. Jezzi regarded intermittent communication trouble as familiar in the unit. The original tower recordings and equipment tests were not available for this review, so the competing interpretations remain dependent on participant testimony.
The associated ground-witness family entered the investigation after a Mansfield News Journal appeal on 19 August 1976. Zeidman says their first extensive interviews followed that contact, and that she combined excerpts from several sessions into a chronological narrative. This gives the ground account a clear collection history, almost three years after the flight and after the appeal had described and illustrated the crew's object. Their account should be evaluated as later testimony from a different position. It supplies no direct check on cockpit readings or control inputs.
The crew's corroboration is specific to their viewing positions and duties. Several men described an unfamiliar lighted source during a flight that prompted evasive action; Coyne supplied the principal control and instrument account. Jezzi's restricted view, Healey's changing recollection of illumination and the later compass history define the extent of agreement. The reported encounter and higher altitude merit analysis, while an extraordinary lifting or interference mechanism would require evidence beyond the observations preserved here.
Key dates
18 October 1973
The crew reports an apparent near collision near Mansfield during the return flight from Columbus to Cleveland.
19 October 1973
Healey records an account with a colleague; the Army disposition form later records notification to the command that afternoon.
21 October 1973
The Plain Dealer publishes Coyne's account, including the body description, green cabin illumination and altitude claim.
23 November 1973
A disposition form signed by all four crewmen records the reported approach, descent, communication interruption and later climb indication.
1 December 1973
Yanacsek signs an operational hazard form describing the approach and evasive action.
24 January 1974
Hynek interviews Coyne in a helicopter of the same model.
19 August 1976
A newspaper appeal prompts contact from the later ground-witness family.
12 February 1977
Hynek and Zeidman interview Jezzi, whose account distinguishes his departing-light observation from the others' approach descriptions.
27 November 1978
Coyne presents his account and aviation-reporting proposals to a UN committee in a private capacity.
March 1979
CUFOS publishes Zeidman's monograph; the UN circulates its partial verbatim record of the November meeting.
Signed document reproduced in Zeidman's Appendix A, PDF page 122, inspected as a scan. All four crew signatures visible. This is their attested report, not an independent Army finding identifying the object.
Reproduced DA Form 2396, PDF page 120, inspected as a scan. Describes the 18 October occurrence; signature date reads 1 December 1973. Range and proximity entries are witness estimates.
Original newspaper clipping reproduced at PDF page 123, inspected as a scan. John P. Coyne interviews the captain, identified in the article as his second cousin. Early public account; reported altitudes differ from the later Army form.
CUFOS monograph, March 1979. Printed pages 7–20 read in extracted text; selected scans checked, including interview chronology and later compass testimony. Reproduces the 24 January 1974 Hynek interview and later Zeidman interviews; original recordings not auditioned.
Printed pages 21–36 read; key passages inspected as scans. Identifies Healey's 19 October 1973 tape and December 1976 interview, and Jezzi's 12 February 1977 interview. Yanacsek's detailed interview has no explicit date at its opening.
Printed pages 77–86 read, with source-specific scan checks. Contains reported maintenance enquiries and the 2 April 1978 discussion. Technical interpretations are investigator and consultant positions; original maintenance records were not inspected.
Printed pages 37 and 50–51, and the reproduced 19 August 1976 clipping at printed page 114, inspected. Used for acquisition chronology and editorial integration of several interviews; no claim of independently verifying the original tapes.
A/SPC/33/PV.35, partial verbatim record circulated 6 March 1979. Cover and PDF pages 23–28 inspected as scans. Grenada's introduction specifies Coyne's private capacity; this is an official record of later witness testimony.
Chapter 3, page 3-2 inspected for the collective's function in changing rotor-blade pitch. General technical explanation, not an investigation of the 1973 flight.