# NTSB LAX07LA005: Robinson R22 Beta, N821SH, Upland, CA, October 8, 2006 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 8, 2006, 13:12 local (20:12 UTC) - Place: Upland, CA - Coordinates: 34.111667, -117.687225 - Nearby events: https://openairdocs.org/map.md?lat=34.1117&lon=-117.6872&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 31, 2008 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 64665 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX07LA005 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/64665/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=64665 - Page: https://openairdocs.org/ntsb/LAX07LA005 ## Probable cause Disconnection of the throttle control linkage due to improper maintenance, which resulted in a loss of engine power during initial climb. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, takeoff - initial climb - throttle/power lever,push/pull rod - disconnected (cause) - maintenance - improper, other maintenance personnel (cause) - Forced landing, descent - emergency - autorotation - performed, pilot in command(cfi) - Hard landing, landing - flare/touchdown - terrain condition - ground ## Analysis The helicopter's engine suddenly lost power during initial climb on an instructional flight. The certified flight instructor (CFI) took the controls and autorotated to a hard touchdown in a gravel pit. After securing the helicopter, the CFI inspected the throttle linkage. He reported that something appeared disconnected behind the firewall. "When rotating the throttle from full open to full close, the push/pull tube that connects to the carburetor does not move." The subsequent examination of the helicopter's throttle spring assembly revealed that on a previous occasion improper maintenance had been performed. The helicopter's maintenance records did not reflect maintenance in this area. The inspection revealed that the upper rod end bearing was disconnected from the lower portion of the rod because it had not been safety wired as required. This maintenance error resulted in a total loss of throttle control. ## Factual narrative 'THIS CASE WAS MODIFIED APRIL 8, 2008." On October 8, 2006, about 1312 Pacific daylight time, a Robinson R22 Beta, N821SH, experienced a loss of engine power during initial climb from the Cable Airport, Upland, California. The certified flight instructor (CFI) took the flight controls from his private pilot student. The CFI autorotated into a gravel pit adjacent to runway 24. The touchdown was hard, and the helicopter was substantially damaged. Neither the CFI nor student was injured during the instructional flight. The helicopter was owned and operated by Silver State Helicopters, LLC., North Las Vegas, Nevada. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight was performed under the provisions of 14 Code of Federal Regulations Part 91, and it originated from Chino, California, about 1230. The CFI reported to the National Transportation Safety Board investigator that during the first portion of the flight no evidence of any mechanical malfunction was apparent. Upon arriving at Chino they made an approach to the southeast helicopter pads and then departed. During the subsequent climb out from the Cable Airport, the engine and main rotor rpm decreased. The CFI reported that an effort was made to correct for the low engine/rotor rpm by rolling on (increasing) throttle and lowering the collective, but there was no response from the throttle control. Thereafter, the CFI took the controls from his student and initiated an autorotative descent. Touchdown was hard, and the main rotor blades severed the tail boom. After securing the helicopter the CFI stated that he inspected the throttle linkage. He reported that something appeared disconnected behind the firewall. "When rotating the throttle from full open to full close, the push/pull tube that connects to the carburetor does not move." Under the direction of the Safety Board, the helicopter was examined by the Federal Aviation Administration (FAA) coordinator. The FAA coordinator reported that he examined the helicopter's throttle over travel spring assembly. He observed evidence that it had been removed and reinstalled improperly on a previous occasion. The helicopter's maintenance records did not reflect this maintenance, or any maintenance in this area. The FAA coordinator additionally reported that the specific examination finding was that the upper rod end bearing was separated from the lower portion of the rod because it had not been safety wired as required. He opined that following this disconnection, all throttle control capability was lost. ## Aircraft - Registration: [N821SH](https://openairdocs.org/aircraft/N821SH), registered now, S/N 3774, built 2005 (OpenAirDocs) - Reported make and model: Robinson R22 Beta - Registry model: [Robinson Helicopter R22 BETA](https://openairdocs.org/model/robinson-helicopter-r22-beta) (registry code 7640110) (OpenAirDocs) - Registry engine: [Lycoming O-360 series](https://openairdocs.org/engine/lycoming-o-360-series) (registry code 41575, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 3774 - Airframe hours: 1809 - Engines: Lycoming O-360-J2A 131 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Silver State Helicopters, LLC - Registered owner: Silver State Helicopters, LLC - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, October 1, 2006 - Departed: CCB, Upland, CA - Destination: POC, La Verne, CA - Airport: CCB, Cable, runway 24, 3,864 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 24; injuries: none; flight instructor, commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review April 1, 2006; seat: left; flight hours: 841 total, 797 in this make and model, 800 as pilot in command, 395 in the last 90 days, 125 in the last 30 days, 8 in the last 24 hours - Pilot; age 27; injuries: none; private; medical: class 1, without waivers/limitations; last flight review May 1, 2005; seat: right; flight hours: 110 total, 103 in this make and model, 66 as pilot in command, 6 in the last 90 days, 2 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 5 knots - Visibility: 5 statute miles - Lowest ceiling: none - Temperature: 63 °F - Altimeter: 29.95 inHg - Observed at: POC, 5 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 20061008025549A](https://openairdocs.org/incident/20061008025549A), Oct 8, 2006: Robsin R22BETA, Upland, CA, Substantial damage. (-23) Loss of engine and rotor RPM and subsequent hard landing was due to the separation of the upper rod end from the throttle overtravel spring assembly… ## Docket (1 files) The files NTSB released with the investigation on February 20, 2008, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=64665. 30 KB in all. - Statement from FAA (item 1, .PDF, 30 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40287356&FileExtension=.PDF&FileName=Statement%20from%20FAA%20-Master.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.