1972 Lake Winnebago mid-air collision
Air Wisconsin de Havilland DHC-6 and North Central Airlines Convair 580 · Mid-air collision
Event
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Unknown
- Event fatalities
- 13 · all aircraft and ground
- Ground fatalities
- 0
- Occupants
- Unknown
- Survivors
- 0
- InjuriesFatal: death within 30 days. Serious: over 48 hours in hospital within a week, most broken bones, severe bleeding, nerve or organ damage, or serious burns. Minor: anything less. Glossary
- 0 serious · 0 minor (NTSB)
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aircraft 1 · de Havilland DHC-6
- Aircraft type
- de Havilland DHC-6
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N4043B
- Operator
- Air Wisconsin
- Onboard fatalities
- Unknown
- Occupants
- Not stated
- Survivors
- 0
- InjuriesFatal: death within 30 days. Serious: over 48 hours in hospital within a week, most broken bones, severe bleeding, nerve or organ damage, or serious burns. Minor: anything less. Glossary
- None · no survivors
- Route
- From Chicago O'Hare International Airport (ORD)To Appleton International Airport (ATW)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air carrier (scheduled domestic passenger service)
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Collision with aircraft - both in flight
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Aircraft 2 · Convair 580
- Aircraft type
- Convair 580
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N90858
- Operator
- North Central Airlines
- Onboard fatalities
- Unknown
- Occupants
- Not stated
- Survivors
- 0
- InjuriesFatal: death within 30 days. Serious: over 48 hours in hospital within a week, most broken bones, severe bleeding, nerve or organ damage, or serious burns. Minor: anything less. Glossary
- None · no survivors
- Route
- From Green Bay, WITo General Mitchell International Airport (MKE)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air carrier (scheduled domestic passenger service)
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Collision with aircraft - both in flight
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Personnel › Pilot of other aircraft
- Pilot in command › Failed to see and avoid other aircraft
Approximate · Coordinates from the Wikipedia article; not checked against an investigation report.
From the Wikipedia article
On June 29, 1972, North Central Airlines Flight 290 collided in mid-air with Air Wisconsin Flight 671 over Lake Winnebago near Fox Crossing, Wisconsin, in the United States. Both aircraft crashed into the lake, killing all 13 people on board both aircraft.
Collision
Operating in bright sunshine beneath a scattered cloud layer, Flight 290 and Flight 671 collided at 10:36:47 a.m. CDT over Wisconsin's Lake Winnebago about 6 nmi south of Appleton and 2.5 nmi east of Neenah, Wisconsin, at an altitude of about 2,500 feet (762 m). The left wing of Flight 671 hit the left wing of Flight 290. The collision resulted in an explosion which tore off most of the Twin Otter's wing, and around a quarter of the CV-580's left wing. The collision left both aircraft uncontrollable, resulting in both crashing into Lake Winnebago around 2 nmi east of Neenah Light.
The National Transportation Safety Board noted that the North Central crew would have had to look toward the sun to see the approaching Air Wisconsin plane and concluded that they took no evasive action. Some eyewitnesses believed that the Air Wisconsin Twin Otter began a turn seconds before the collision, but the NTSB did not find sufficient evidence to conclude that the Air Wisconsin crew took evasive action. The rate of closure during the final five seconds before the collision was 688 ft/s.
Investigation and cause
Investigation
The National Transportation Safety Board released its report on the accident on April 25, 1973. It was "unable to determine why each crew failed to see and avoid the other aircraft," and concluded that the crash resulted from "the failure of both flight crews to detect visually the other aircraft in sufficient time to initiate evasive action," and stated that it believed "that the ability of both crews to detect the other aircraft in time to avoid a collision was reduced because of the atmospheric conditions and human visual limitations." The NTSB speculated that both flight crews could have been scanning instruments in preparation for descent to their respective destinations at the time of the collision, and this could have reduced their chances of spotting one another. The report also noted that the decision by both flight crews to fly under VFR rather than IFR and the fact that neither captain requested in-flight advisories deprived both aircraft of air traffic control support, and that such support to even one of the aircraft would have ensured sufficient separation to avoid a collision.
The NTSB recommended that the Federal Aviation Administration create a standardized method for training and grading flight crews in visual search techniques and time-sharing between instrument checks and visual searches, and that the FAA expedite the development of anticollision systems.
Text from the Wikipedia article “1972 Lake Winnebago mid-air collision” (revision 1362215131, retrieved 2026-09-18) by its authors, under CC BY-SA 4.0. Extracted as plain text: references, tables, images and some sections are left out. Read the article
NTSB remarks
BOTH ACFT SANK IN LAKE WINNEBAGO.
BOTH CREWS FAILED TO SEE AND AVOID.DETECTION REDUCED BY ATMOSPHERIC COND & HUMAN VISUAL LIMITATION
NTSB's remark from its 1962–1981 archive, as recorded (abbreviated, at most 98 characters): the archive has no narrative
Sources
Wikipedia article: 1972 Lake Winnebago mid-air collision
- Revision
- 1362215131 · 2026-07-02 · retrieved 2026-09-18
- Wikidata
- Q14714402
- Licence
- Text CC BY-SA 4.0, by the article's authors; Wikidata CC0; town positions GeoNames (CC BY 4.0)
NTSB record
- Event ID
- 19720629P044010
- Case number
- Unknown
- Dataset
- historical-pre1982
- Source SHA-256
- abe1a933b4b73583d61684309f7f0610c281e3c1de3537c6471bf2a98ba6481d
Where each value comes from
- Record
- Wikipedia article "1972 Lake Winnebago mid-air collision" (page 33739143, revision 1362215131); merged with NTSB case NTSB19720629P044010 (PRE1982 tblFirstHalf (one row per aircraft, grouped by date, place and time))
- Date
- NTSB record NTSB19720629P044010: PRE1982 DATE_OCCURRENCE
- Place and country
- Wikipedia infobox: site; country from NTSB record NTSB19720629P044010
- Map position
- Wikipedia: Wikipedia article coordinates
- Aircraft, operator and route
- NTSB record NTSB19720629P044010: PRE1982 REGIST_NO, ACFT_MAKE, ACFT_MODEL; gaps from Wikipedia infobox: aircraft type, registration, operator, origin and destination; route airports from the linked airport articles' Wikidata codes (OurAirports)
- Operation
- NTSB record NTSB19720629P044010: operated under Part 121: Air carrier (scheduled domestic passg.svc)
- Fatalities
- NTSB record NTSB19720629P044010: PRE1982 TOTAL_ABRD_FATAL of each aircraft, plus people on the ground and others outside the aircraft
- Ground fatalities
- NTSB record NTSB19720629P044010: events.inj_f_grnd
- Summary
- Wikipedia infobox: summary
Source notes (4)
- One occurrence in two sources, merged: the Wikipedia article "1972 Lake Winnebago mid-air collision" and NTSB case NTSB19720629P044010, matched by the same aircraft registration and date. For this US event the NTSB's values are used where the two differ; each value names its source.
- From NTSB's 1962-1981 archive (PRE1982), which holds at most a short remark (98 characters, abbreviated) instead of a narrative; the accident type, phase of flight, causes and conditions are NTSB's codes, decoded as the archive defines them.
- Reviewed means this record passed the site's consistency check, not that it was checked against a narrative or report - there is none to check against.
- The operation category is mapped from the archive's operator and operation codes and has not been reviewed.