# NTSB CEN21LA420: Quad City Ultralight Challenger II, N778H, Rogers City, MI, September 11, 2021

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Class 3 · Limited · Final report
- Date: September 11, 2021, 07:45 local (11:45 UTC)
- Place: Rogers City, MI
- Coordinates: 45.407083, -83.812861 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.4071&lon=-83.8129&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Defining event: [Takeoff: Aircraft structural failure](https://openairdocs.org/ntsb-events/337)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 3
- NTSB office: Central Region
- Parties: Federal Aviation Administration - Grand Rapids FSDO
- NTSB case key (mKey): 103862
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN21LA420
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103862/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103862
- Page: https://openairdocs.org/ntsb/CEN21LA420

## Probable cause

The separation of the right wing’s forward lift strut from the fuselage due to a missing nylon-insert lock nut. Contributing to the accident was the noncertificated pilot’s decision to operate the airplane even though a condition inspection had not been completed in the 13 years since the airplane received its experimental airworthiness certificate.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Wing structure: wing auxiliary structure](https://openairdocs.org/ntsb-findings/01035720): Aircraft › Aircraft structures · Failure (probable cause); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-findings/01035720/cases.md?model=059010P), [All aircraft, 3 cases](https://openairdocs.org/ntsb-findings/01035720/cases.md)
- [Wing structure: attach fittings (on wing)](https://openairdocs.org/ntsb-findings/01035740): Aircraft › Aircraft structures · Failure (probable cause); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-findings/01035740/cases.md?model=059010P), [All aircraft, 21 cases](https://openairdocs.org/ntsb-findings/01035740/cases.md)
- [Wing structure: attach fittings (on wing)](https://openairdocs.org/ntsb-findings/01035740): Aircraft › Aircraft structures · Not inspected (probable cause); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-findings/01035740/cases.md?model=059010P), [All aircraft, 21 cases](https://openairdocs.org/ntsb-findings/01035740/cases.md)
- [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Owner/builder (probable cause); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=059010P), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Takeoff: Aircraft structural failure](https://openairdocs.org/ntsb-events/337) (defining event); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-events/337/sequence.md?model=059010P), [All aircraft, 290 cases](https://openairdocs.org/ntsb-events/337/sequence.md)
- [Takeoff: Loss of control on ground](https://openairdocs.org/ntsb-events/230); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-events/230/sequence.md?model=059010P), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md)
- [Takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490); cases with it: [Quad City Ultralight CHALLENGER II, 1 case](https://openairdocs.org/ntsb-events/490/sequence.md?model=059010P), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md)

## Analysis

The noncertificated pilot was departing on a local flight. The pilot reported that about 100 ft into the takeoff roll the airplane began to swerve right, but before he could abort the takeoff, he heard a bang and the airplane pitched up and rolled. A witness reported that the airplane abruptly pitched up, rolled right, and impacted the ground in a left-wing-down attitude. The witness stated that the airplane completed about 270° of right roll when the left wing impacted the ground. The airplane sustained substantial damage to the left wing, fuselage, tailboom, and left horizontal stabilizer. Postaccident examination of the airplane revealed that the right wing’s forward lift strut separated from the fuselage longeron. The channel bracket remained attached to the lift strut, but the attachment bolt pulled out of the fuselage longeron. The nylon-insert lock nut that normally secured the attachment bolt to the fuselage longeron was not located during the investigation. Flight control continuity was confirmed from the cockpit controls to each flight control surface. The pilot did not maintain maintenance records for the airplane, nor had the airplane undergone a condition inspection since the Federal Aviation Administration (FAA) issued the experimental airworthiness certificate in December, 2007.

## Factual narrative

The pilot did not maintain maintenance records for the airplane, nor had the airplane undergone a condition inspection since the FAA issued the experimental airworthiness certificate on December 14, 2007. On September 11, 2021, about 0745 eastern daylight time, a Quad City Ultralight Challenger II experimental airplane, N778H, was substantially damaged when it was involved in an accident near Rogers City, Michigan. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The noncertificated pilot reported that about 100 ft into the takeoff roll on runway 27 the airplane began to swerve right, but before he could abort the takeoff, he heard a bang and the airplane pitched up and rolled. A witness reported that the airplane abruptly pitched up, rolled right, and impacted the ground in a left-wing-down attitude. The witness stated that the airplane completed about 270° of right roll when the left wing impacted the ground. A search of FAA airman certification records found no record of a pilot certificate ever being issued to the pilot. The pilot reported that he had previous flying experience in 14 CFR Part 103 ultralights. Postaccident examination revealed substantial damage to the airplane’s left wing, fuselage, tailboom, and left horizontal stabilizer. Flight control continuity was confirmed from the cockpit controls to each flight control surface. Further examination of the right wing revealed that the forward lift strut separated from the fuselage longeron, as shown in figure 1. The channel bracket remained attached to the lift strut, but the AN4-24A bolt pulled out of the fuselage longeron. The 0.25-inch AN365-248 nylon-insert lock nut, depicted in figure 2, that normally secured the AN4-24A bolt was not located during the investigation. Figure 1. Lower attachment point of the right wing forward lift strut (FAA photos). Figure 2. Wing lift strut assembly, lower attachment.

## Aircraft

- Registration: [N778H](https://openairdocs.org/deregistered/N778H-2022-06-04), registration cancelled 2022-06-04, S/N CH2-0905-CW-2671, built 2005 (OpenAirDocs)
- Reported make and model: Quad City Ultralight Challenger II (NO SERIES)
- Registry model: [Quad City Ultralight CHALLENGER II](https://openairdocs.org/model/quad-city-ultralight-challenger-ii) (registry code 059010P) (OpenAirDocs)
- Registry engine: [Rotax 503 DCDI](https://openairdocs.org/engine/rotax-503-dcdi) (registry code 55566, 2 cycle) (OpenAirDocs)
- Category: Airplane
- Serial number: CH2-0905-CW-2671
- Year built: 2005
- Airframe hours: 139.9
- Engines: Rotax 503 UL 52 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Airworthiness certificate: Special, Experimental light sport (Special)
- Departed: PZQ, Rogers City, MI
- Destination: PZQ, Rogers City, MI
- Airport: PZQ, Presque Isle County Airport, runway 27, 4,106 × 75 ft, asphalt
- Equipment: Airframe parachute

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 60; injuries: minor; seat: front; restraint: 3-point; flight hours: 200 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 200° at 9 knots
- Visibility: 10 statute miles
- Lowest ceiling: 10,000 ft overcast
- Temperature: 59 °F, dew point 55 °F
- Altimeter: 29.89 inHg
- Observed at: KPZQ
- METAR: METAR KPZQ 111135Z AUTO 20009KT 10SM OVC100 15/13 A2989 RMK AO2 T01460125=

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 20210911015569A](https://openairdocs.org/incident/20210911015569A), Sep 11, 2021: Quad City Ultralight CHALLENGER II, Rogers City, MI, Substantial damage. On September 11, 2021, at approximately 07:50 local time, an experimental light-sport aircraft a model Challenger II, N788H, [privacy data omitted]operated by…

## Docket (12 files)

The files NTSB released with the investigation on September 14, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103862. 11.0 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 7 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16021339&FileExtension=pdf&FileName=01%20-%20Pilot%20Report_Redacted-Rel.pdf
- Pilot statement (item 2, PDF, 1 page, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16022731&FileExtension=pdf&FileName=02%20-%20Pilot%20Statement_Redacted-Rel.pdf
- FAA record of conversation (item 3, PDF, 2 pages, 82 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16021643&FileExtension=pdf&FileName=03%20-%20FAA%20Record%20of%20Conversation-Rel.pdf
- Witness statement (item 4, PDF, 2 pages, 265 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16022025&FileExtension=pdf&FileName=04%20-%20Witness%20Statement_Redacted-Rel.pdf
- NTSB record of conversation (item 5, PDF, 2 pages, 94 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16021349&FileExtension=pdf&FileName=05%20-%20NTSB%20Record%20of%20Conversation-Rel.pdf
- FAA wreckage examination summary (item 6, PDF, 1 page, 149 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16024497&FileExtension=pdf&FileName=06%20-%20FAA%20Wreckage%20Examination%20Summary_Redacted-Rel.pdf
- Right wing forward lift strut separation photos (item 7, PDF, 1 page, 1 photo, 412 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16021653&FileExtension=pdf&FileName=07%20-%20Right%20Wing%20Forward%20Lift%20Strut%20Separation%20Photos-Rel.pdf
- Wing strut installation drawing (item 8, PDF, 1 page, 32 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16024507&FileExtension=pdf&FileName=08%20-%20Wing%20Strut%20Installation%20Drawing-Rel.pdf
- Airplane logbook (item 9, PDF, 12 pages, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16021663&FileExtension=pdf&FileName=09%20-%20Airplane%20Logbook_Redacted-Rel.pdf
- Email correspondence with FAA inspector about pilot certificate status (item 10, PDF, 2 pages, 177 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16022035&FileExtension=pdf&FileName=10%20-%20Email%20Correspondence%20with%20FAA%20Inspector%20about%20Pilot%20Certificate%20Status_Redacted-Rel.pdf
- Weather summary (item 11, PDF, 2 pages, 107 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16021359&FileExtension=pdf&FileName=11%20-%20Weather%20Summary-Rel.pdf
- Photos (item 12, PDF, 7 pages, 7 photos, 4.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16024389&FileExtension=pdf&FileName=12%20-%20Photos-Rel.pdf

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.