# NTSB WPR18LA005: Piper PA 24-250, N7892P, Hillsboro, OR, October 5, 2017 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: October 5, 2017, 14:20 local (21:20 UTC) - Place: Hillsboro, OR - Coordinates: 45.428333, -122.942222 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=45.4283&lon=-122.9422&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviaiton Administration - NTSB case key (mKey): 96155 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR18LA005 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/96155/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=96155 - Page: https://openairdocs.org/ntsb/WPR18LA005 ## Probable cause The student's pilot’s failure to maintain adequate airspeed during approach and subsequent exceedance of the critical angle of attack during a go-around, which resulted in an aerodynamic stall and a subsequent hard landing. Contributing to the accident was the flight instructor's delayed remedial action during the attempted go-around. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Student/instructed pilot (probable cause) - [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Instructor/check pilot (probable cause) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause) - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause) ## Analysis As the student pilot was approaching the runway for a practice soft-field, full-stop landing, the airplane descended faster than expected and the nose pitched up. The airplane's airspeed was slow, and the flight instructor called for a go-around. During the go-around, the flight instructor told the student pilot to apply power faster. Subsequently, the airplane exceeded its critical angle of attack and aerodynamically stalled, settled toward the ground, struck the ground hard short of the runway, and then bounced onto the runway, sustaining substantial damage to the fuselage and wings. The accident might have been avoided if the flight instructor had intervened or taken control of the airplane earlier in the sequence. ## Factual narrative On October 5, 2017, about 1420 Pacific daylight time, a Piper PA-24-250, airplane, N7892P, was substantially damaged when it was involved in an accident at Hillsboro, Oregon. The flight instructor and student pilot were seriously injured. The airplane was operated by Twin Oaks Airpark Inc. as a Title 14 Code of Federal Regulations Part 91 instructional flight. The flight instructor reported that, during a practice soft field full stop landing, as the student pilot was approaching the runway, the airplane descended quicker than expected. As the airplane got closer to the runway, the airspeed was decreasing, the nose angle was increasing and he called out to the student "airspeed." A go-around was called and during the go-around, the airplane aerodynamically stalled, and settled towards the runway. The airplane struck short of the runway hard, and then bounced onto the runway. According to the student pilot the soft field landing had a shallower glide path than a normal landing. He stated that while flying the approach, he noticed that the airspeed was about 15 knots slow. Subsequently, the flight instructor called for him to go-around. During the go-around, the flight instructor told him to apply the power quicker. As the airplane approached the flare, he felt the airplane settle towards the ground in an aerodynamic stall. Furthermore, he stated that he noticed no wind (crosswind or downdraft) on final. Both wings and the fuselage were substantially damaged. The pilot reported no preaccident mechanical failure or malfunction with the airplane that would have precluded normal operation. ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR go-around: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - [Approach-VFR pattern final: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060) - [Landing-flare/touchdown: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event) - [Landing-flare/touchdown: Landing area undershoot](https://openairdocs.org/ntsb-events/370) - [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092) ## Aircraft - Registration: [N7892P](https://openairdocs.org/deregistered/N7892P-2020-02-20), registration cancelled 2020-02-20, S/N 24-3121, built 1962 (OpenAirDocs) - Reported make and model: PIPER PA 24-250 (250) - Registry model: [Piper PA-24-250](https://openairdocs.org/model/piper-pa-24-250) (registry code 7102404) (OpenAirDocs) - Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 24-3121 - Year built: 1962 - Airframe hours: 7081.9 - Engines: LYCOMING O-540 SERIES 250 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, August 15, 2019 - Departed: 7S3, Hillsboro, OR - Destination: 7S3, Hillsboro, OR - Airport: 7S3, Stark'S Twin Oaks Airpark, runway 02, 2,465 × 48 ft, asphalt - Equipment: ADS-B, Auto-pilot, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 68; injuries: serious; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review February 18, 2017; seat: right; restraint: 3-point; flight hours: 7,056 total, 168 in this make and model, 6,288 as pilot in command, 131 in the last 90 days, 52 in the last 30 days, 5 in the last 24 hours - Student pilot; age 39; injuries: serious; commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review May 9, 2017; seat: left; restraint: 3-point; flight hours: 2,161 total, 13 in this make and model, 1,784 as pilot in command, 22 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 3 knots - Visibility: 10 statute miles - Temperature: 72 °F, dew point 45 °F - Altimeter: 30.06 inHg - Observed at: KHIO, 7 nm away ## 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 20171005014339A](https://openairdocs.org/incident/20171005014339A), Oct 5, 2017: Piper PA-24-250, Hillsboro, OR, Substantial damage. The PIC, who was acting as a flight instructor and a student were returning to Twin Oaks airpark (7S3) at the end of a lesson in the local area. The intention… ## Docket (4 files) The files NTSB released with the investigation on October 9, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=96155. 6.4 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8635165&FileExtension=pdf&FileName=NTSB%20Form%206120-1_Redacted-Rel.pdf - Meteorology (item 2, PDF, 6 pages, 396 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8632847&FileExtension=pdf&FileName=WPR18LA005%20-%20Hillsboro,%20OR%20Weather%20_Redacted-Rel.pdf - Record of conversation (item 3, PDF, 2 pages, 70 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8631964&FileExtension=pdf&FileName=Record%20of%20Conversation%20WPR18LA005%20Final-Rel.pdf - Photo (item 4, PDF, 1 page, 452 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=8633355&FileExtension=pdf&FileName=Accident%20Picture-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.