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CHI00FA003 · Beech D-45

1 Oct 1999 · Oswego, IL, United States

Beech D-45 and Beech T-34 · Accident: midair collision while maneuvering

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Event

NTSB case
CHI00FA003
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
Completed
API-reported fatalities
1 · all aircraft and ground
Ground fatalities
0
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
General aviation
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 · Beech D-45

Aircraft type
Beechcraft D-45
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
N300SH
Operator
Unknown
Onboard fatalities
Unknown
Route
From Naper Aero Club Airport (LL10), Naperville, ILTo CGX · Chicago, IL
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 91: General Aviation
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
Maneuvering · turn to reverse direction
First occurrenceThe 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
Midair collision
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 · Beech T-34

Aircraft type
Beechcraft T-34
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
N5367G
Operator
Unknown
Onboard fatalities
Unknown
Route
From Naper Aero Club Airport (LL10), Naperville, ILTo CGX · Chicago, IL
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 91: General Aviation
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
Maneuvering · turn to reverse direction
First occurrenceThe 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
Midair collision
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Substantial

Cause areas

  • Other institution › Procedure inadequate
  • Pilot in command › Visual lookout, not obtained
  • Pilot of other aircraft › Visual lookout, not obtained

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

N300SH, a Beech D-45, was destroyed on impact with terrain following a midair collision with N5367G, a Beech T-34, during a practice maneuver by the Lima Lima Flying Squadron. Both aircraft departed in sequence from 6-ship delta formation to perform a maneuver called a pop top break. The pop top break involved each aircraft to depart from the formation in sequence by entering a climbing 180-degree turn to follow the lead aircraft in trail. The narrow area of the human eye's visual field is approximately 10-15 degrees. A video tape of the accident flight shows a delayed entry into the turn by the D-45 relative to the T-34's entry into the maneuver. The pilot of the T-34 stated that he did not see the D-45 prior to the midair collision. The Lima Lima Flying Squadron did not have procedures in place to recover or adjust for maneuvers that were not successful.

Probable cause

the visual lookout not obtained by the pilot of the Beech T-34 and the inadequate procedure by the Lima Lima Flying Squadron. The delayed entry into the maneuver by the pilot of the Beech D-45 was a contributing factor.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record CHI00FA003
Event ID
20001212X19911
Case number
CHI00FA003
Dataset
historical-pre2008
Source SHA-256
89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
  • Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
  • Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
  • The date is the local date, which is the same as the UTC date the NTSB stores.
  • API snapshot SHA-256: 7fd402b49261178d729ab055af99116127eaf35efa4998531e05efa450f7afff; retrieved 2026-09-20T21:44:40.808Z.