# NTSB WPR26LA059: Waco RNF, N110Y, Phoenix, AZ, December 14, 2025

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Limited · Final report
- Date: December 14, 2025, 09:04 local (16:04 UTC)
- Place: Phoenix, AZ
- Coordinates: 33.688306, -112.08255
- Nearby events: https://openairdocs.org/map.md?lat=33.6883&lon=-112.0825&mi=10
- Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping)
- Defining events: [Taxi: Ground collision](https://openairdocs.org/ntsb-events/200); [Taxi: Ground collision](https://openairdocs.org/ntsb-events/200)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed, report February 12, 2026
- Report: Approved by Office Director
- Investigation class: Class 4 - Basic report with no Prelim publish
- NTSB office: Western Pacific Region
- Parties: FAA
- NTSB case key (mKey): 202162
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR26LA059
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/202162/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=202162
- Page: https://openairdocs.org/ntsb/WPR26LA059

## Probable cause (aircraft 1)

The biplane pilot’s failure to maintain adequate clearance from the low-wing airplane while taxiing.

## Findings

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

- [Attention/monitoring: monitoring other aircraft](https://openairdocs.org/ntsb-findings/02021540): Personnel issues › Psychological · Pilot (probable cause), aircraft 1; cases with it: [Waco RNF, 1 case](https://openairdocs.org/ntsb-findings/02021540/cases.md?model=9600422), [All aircraft, 231 cases](https://openairdocs.org/ntsb-findings/02021540/cases.md)
- [Physical workspace: visibility](https://openairdocs.org/ntsb-findings/03041020): Environmental issues › Task environment · Contributed to outcome (probable cause), aircraft 1; cases with it: [Waco RNF, 1 case](https://openairdocs.org/ntsb-findings/03041020/cases.md?model=9600422), [All aircraft, 25 cases](https://openairdocs.org/ntsb-findings/03041020/cases.md)
- [Attention/monitoring: monitoring other aircraft](https://openairdocs.org/ntsb-findings/02021540): Personnel issues › Psychological · Pilot of other aircraft (probable cause), aircraft 2; cases with it: [Cirrus Design SR20, 3 cases](https://openairdocs.org/ntsb-findings/02021540/cases.md?model=2130000), [All aircraft, 231 cases](https://openairdocs.org/ntsb-findings/02021540/cases.md)

## Sequence of events

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

- [Taxi: Loss of visual reference](https://openairdocs.org/ntsb-events/402), aircraft 1; cases with it: [Waco RNF, 1 case](https://openairdocs.org/ntsb-events/402/sequence.md?model=9600422), [All aircraft, 242 cases](https://openairdocs.org/ntsb-events/402/sequence.md)
- [Taxi: Ground collision](https://openairdocs.org/ntsb-events/200) (defining event), aircraft 1; cases with it: [Waco RNF, 1 case](https://openairdocs.org/ntsb-events/200/sequence.md?model=9600422), [All aircraft, 618 cases](https://openairdocs.org/ntsb-events/200/sequence.md)
- [Taxi: Ground collision](https://openairdocs.org/ntsb-events/200) (defining event), aircraft 2; cases with it: [Cirrus Design SR20, 2 cases](https://openairdocs.org/ntsb-events/200/sequence.md?model=2130000), [All aircraft, 618 cases](https://openairdocs.org/ntsb-events/200/sequence.md)

## Analysis (aircraft 1)

The pilot of the tailwheel equipped biplane reported that while taxiing behind a low-wing airplane, he was performing s-turns to improve forward visibility. During the s-turns, the pilot momentarily lost sight of the low-wing airplane, and when he regained sight of it, he realized it had stopped. The pilot applied full right rudder and braking to avoid a collision; however, the biplane’s upper left wing struck the low-wing airplane’s rudder. During the collision sequence, the biplane’s propeller struck the low-wing airplane’s horizontal stabilizer and elevator. The biplane sustained substantial damage to the upper left wing, and the low-wing airplane sustained substantial damage to the empennage. The pilots of both airplanes reported that there were no preaccident mechanical malfunctions or failures with their airplanes that would have precluded normal operation.

## Aircraft 1

- Registration: [N110Y](https://openairdocs.org/aircraft/N110Y), registered now, S/N 3298, built 1930 (OpenAirDocs)
- Reported make and model: WACO RNF
- Registry model: [Waco RNF](https://openairdocs.org/model/waco-rnf) (registry code 9600422) (OpenAirDocs)
- Registry engine: [Warner SS40&50](https://openairdocs.org/engine/warner-ss40-50) (registry code 64503, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 3298
- Year built: 1930
- Airframe hours: 2770
- Engines: Warner S50A 145 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, February 12, 2025
- Destination: Same as departure
- Airport: DVT, Phoenix Deer Valley Airport
- Equipment: Handheld GPS

## Aircraft 2

- Registration: [N506AV](https://openairdocs.org/aircraft/N506AV), registered now, S/N 9469, built 2023 (OpenAirDocs)
- Reported make and model: CIRRUS SR20 (NO SERIES EXISTS)
- Registry model: [Cirrus Design SR20](https://openairdocs.org/model/cirrus-design-sr20) (registry code 2130000) (OpenAirDocs)
- Registry engine: [Lycoming IO-390-C3B6](https://openairdocs.org/engine/lycoming-io-390-c3b6) (registry code 42710, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 9469
- Year built: 2023
- Airframe hours: 1849
- Engines: LYCOMING IO-390-C3B6 215 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Westwind School Of Aeronautics Phoenix LLC DBA, doing business as United Aviate Academy
- Registered owner: Westwind School Of Aeronautics Phoenix LLC DBA
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, December 7, 2025
- Departed: GYR, Goodyear, AZ
- Destination: Same as departure
- Equipment: Angle of attack indicator, Airframe parachute, ADS-B, Stall warning system, Electronic primary flight display, Electronic multifunction display, Auto-pilot

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot, aircraft N110Y; age 74; injuries: none; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 3, with waivers/limitations; last flight review May 20, 2025; flight hours: 3,761 total, 727 in this make and model, 2,000 as pilot in command, 4 in the last 90 days, 2 in the last 30 days, 0 in the last 24 hours
- Flight instructor, aircraft N506AV; age 23; injuries: none; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review October 31, 2025; seat: right; flight hours: 1,395 total, 1,320 in this make and model, 1,091 as pilot in command, 286 in the last 90 days, 96 in the last 30 days, 2 in the last 24 hours
- Student pilot, aircraft N506AV; age 18; injuries: none; student; medical: class 1, without waivers/limitations; seat: left

## Weather

- Conditions: Visual (VMC), Day
- Wind: 50° at 6 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 59 °F, dew point 37 °F
- Altimeter: 30.11 inHg
- Observed at: KDVT, 1 nm away
- METAR: METAR KDVT 141553Z 05006KT 10SM CLR 15/03 A3011 RMK AO2 SLP185 T01500033

## 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 20251214018639A](https://openairdocs.org/incident/20251214018639A), Dec 14, 2025: Waco RNF, Phoenix, AZ, Substantial damage. On December 14, 2025, at Phoenix Deer Valley Airport (kdvt), the pilot of a 1930S-ERA tailwheel aircraft was taxiing, performing from a hangar to runway 7L…

## Docket (4 files)

The files NTSB released with the investigation on February 12, 2026, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=202162. 7.0 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (waco) (item 1, PDF, 10 pages, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19796236&FileExtension=pdf&FileName=6120.1%20N110Y_Redacted-Rel.pdf
- Pilot/operator aircraft accident report, NTSB form 6120.1 (Cirrus instructor) (item 2, PDF, 10 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19796278&FileExtension=pdf&FileName=6120.1%20N506AV_Redacted-Rel.pdf
- Pilot/operator aircraft accident report, NTSB form 6120.1 (Cirrus student) (item 3, PDF, 10 pages, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19795997&FileExtension=pdf&FileName=6120%20student_Redacted-Rel.pdf
- Investigative photographs (item 4, PDF, 6 pages, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19796000&FileExtension=pdf&FileName=Photo%20array-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.

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