# NTSB WPR12TA436: Mcdonnell Douglas Heli 369FF, N911BL, Las Vegas, NV, September 24, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Final report - Date: September 24, 2012, 16:00 local (23:00 UTC) - Place: Las Vegas, NV - Coordinates: 36.207221, -115.184448 - Nearby events: https://openairdocs.org/map.md?lat=36.2072&lon=-115.1844&mi=10 - Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping) - Defining event: [Autorotation: Hard landing](https://openairdocs.org/ntsb-events/092) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report June 11, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: FAA FSDO - NTSB case key (mKey): 85138 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12TA436 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/85138/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=85138 - Page: https://openairdocs.org/ntsb/WPR12TA436 ## Probable cause The pilot’s failure to maintain sufficient airspeed while performing a 270-degree practice autorotation with a gusting tailwind at a high-density altitude. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: incorrect action performance](https://openairdocs.org/ntsb-findings/02041015): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [All aircraft, 1,386 cases](https://openairdocs.org/ntsb-findings/02041015/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) - [Wind: gusts](https://openairdocs.org/ntsb-findings/03034045): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [All aircraft, 1,199 cases](https://openairdocs.org/ntsb-findings/03034045/cases.md) - [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Autorotation: Hard landing](https://openairdocs.org/ntsb-events/092) (defining event); cases with it: [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis The pilot-in-command (PIC), who was giving instruction, was demonstrating a 270-degree autorotation in a gusting west wind at a density altitude of about 5,100 feet. The PIC began the autorotation heading south and turned left; the helicopter experienced a tailwind during the turn. The PIC reported that, because of the tailwind, soon after commencing the autorotation, he increased his bank angle to maintain his ground reference to the intended touchdown point. The pilot receiving instruction stated that, moments later, the helicopter was in a high descent rate, and its airspeed was decreasing. The helicopter impacted terrain in a tail-low attitude. Subsequently, the tailboom separated from the fuselage, the helicopter rolled onto its right side, and the right landing skid folded under the fuselage. ## Factual narrative On September 24, 2012, about 1600 Pacific daylight time, a McDonnell Douglas 369FF helicopter, N911BL, sustained substantial damage during a hard landing following a practice autorotation at North Las Vegas Airport, Las Vegas, Nevada. The two pilots, who both held flight instructor certificates, sustained minor injuries. The helicopter was registered to the Las Vegas Metropolitan Police Department, and the flight was a public aircraft operation. Visual meteorological conditions prevailed for the local training flight, which had originated from North Las Vegas Airport approximately 30 minutes before the accident. A flight plan had not been filed. The pilot-in-command (PIC)/pilot-giving-instruction stated that he and the pilot receiving instruction were alternately practicing autorotations. He decided to demonstrate a 270-degree autorotation to the touchdown point on taxiway Zulu. He began the maneuver on a 180-degree heading, 800 feet above the ground and an airspeed of 85 knots. As he crossed his intended touchdown point, he rolled the throttle back to begin the autorotation. He thought the wind was about 180 to 230 degrees at 15 knots gusting to 26 knots. He entered a left turn. While in the turn, he reported that because of a tailwind he increased his bank angle to maintain his ground reference to the touchdown point. The pilot receiving instruction reported that moments later, the helicopter was in a high rate of descent and its airspeed was decreasing. The helicopter impacted terrain in a tail low attitude. Subsequently the tail boom separated from the fuselage, the helicopter rolled onto its right side, and the right landing skid support structure folded under the fuselage. At 1605, the reported wind at North Las Vegas Airport, elevation 2,205 feet, was 270 degrees at 13 knots gusting to 22 knots. The calculated density altitude, using the barometric pressure of 29.77 inches of mercury, was 5,116 feet. ## Aircraft - Registration: N911BL (not matched to a registry record) - Reported make and model: MCDONNELL DOUGLAS HELI CO 369FF - Category: Helicopter - Serial number: 0601FF - Year built: 1998 - Airframe hours: 20200 - Engines: Allison 250-C30 turbo shaft - Damage: Substantial damage - Flight: Public aircraft - local, Public use - Operator: Las Vegas Metropolitan Police Department - Registered owner: Las Vegas Metropolitan Police Department - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 15, 2012 - Departed: VGT, Las Vegas, NV - Destination: VGT, Las Vegas, NV - Airport: VGT, North Las Vegas Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: minor; flight instructor, private, commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, with waivers/limitations; seat: right; flight hours: 5,774 total, 4,993 in this make and model, 83 in the last 90 days, 22 in the last 30 days, 2 in the last 24 hours - Pilot; age 44; injuries: minor; private, commercial; airplane ratings: single-engine land; instrument ratings: helicopter, airplane; medical: class 2, without waivers/limitations; last flight review February 15, 2011; seat: left; restraint: 4-point; flight hours: 2,500 total, 2,300 in this make and model, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 13 knots, gusting 22 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 93 °F, dew point 34 °F - Altimeter: 29.77 inHg - Observed at: VGT ## 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 20120924021739A](https://openairdocs.org/incident/20120924021739A), Sep 24, 2012: Mcdonnell Douglas Heli Co 369FF, North Las Vegas, NV, Substantial damage. 9-24-2012 At 16:00 local time, N911BL, a MD-369FF (MD530F) public use aircraft was involved in an accident during an instructional flight. The pilot in command… ## Docket (7 files) The files NTSB released with the investigation on April 9, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=85138. 2.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 780 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411076&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Statement - Pilot 1 Giving Instruction (item 2, .PDF, 116 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411077&FileExtension=.PDF&FileName=Statement%20-%20Pilot%201%20Giving%20Instruction-Master.PDF - Statement - Pilot 2 Receiving Instruction (item 3, .PDF, 281 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411078&FileExtension=.PDF&FileName=Statement%20-%20Pilot%202%20Receiving%20Instruction-Master.PDF - Witness Statement (item 4, .PDF, 25 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411079&FileExtension=.PDF&FileName=Witness%20Statement-Master.PDF - FAA Accident Notice with Current Weather (item 5, .PDF, 202 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411080&FileExtension=.PDF&FileName=FAA%20Accident%20Notice%20with%20Current%20Weather-Redacted.PDF - FAA Record of Conversation and Airport Diagram (item 6, .PDF, 628 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411081&FileExtension=.PDF&FileName=FAA%20Record%20of%20Conversation%20and%20Airport%20Diagram-Redacted.PDF - Clark County Airport Incident Report (item 7, .PDF, 91 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411082&FileExtension=.PDF&FileName=Clark%20County%20Airport%20Incident%20Report-Redacted.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.