# NTSB CEN13LA537: Continental Copters Tomcat MK5A, N9005T, Arlington, MN, September 6, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 6, 2013, 10:30 local (15:30 UTC) - Place: Arlington, MN - Coordinates: 44.619998, -94.146942 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.6200&lon=-94.1469&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 23, 2014 - Report: Approved by Office Director - NTSB office: Central Region - NTSB case key (mKey): 88009 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN13LA537 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/88009/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=88009 - Page: https://openairdocs.org/ntsb/CEN13LA537 ## Probable cause The pilot’s failure to maintain control of the helicopter while maneuvering when he removed his hand from the collective control while plugging in his radio connection to his helmet, which resulted in the collective moving to the full-down position. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: unnecessary action](https://openairdocs.org/ntsb-findings/02041045): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Continental Copters TOMCAT MK5A, 1 case](https://openairdocs.org/ntsb-findings/02041045/cases.md?model=2390101), [All aircraft, 52 cases](https://openairdocs.org/ntsb-findings/02041045/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Continental Copters TOMCAT MK5A, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=2390101), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Continental Copters TOMCAT MK5A, 1 case](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=2390101), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Continental Copters TOMCAT MK5A, 2 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2390101), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Continental Copters TOMCAT MK5A, 1 case](https://openairdocs.org/ntsb-events/220/sequence.md?model=2390101), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) ## Analysis After taking off, the pilot applied pesticides to a field and proceeded to the next field located about 3 miles away. While en route, the pilot wanted to call his truck driver over the two-way radio. However, the radio connection to his helmet was unplugged, so he reached to plug it in with his right hand while his left hand transferred from the collective to the cyclic. Immediately after he plugged in the radio connection to his helmet, the collective slammed into the full-down position. The pilot then quickly grabbed the collective and raised it up. He noticed that the helicopter was losing altitude, that the main rotor rpm was decreasing, and that the engine rpm and main rotor rpm needles were split. He twisted the throttle control back and forth with no effect and then attempted to autorotate. The helicopter touched down hard, which resulted in substantial damage to the tailboom. Examination of the helicopter did not reveal any mechanical anomalies that would have precluded normal operation. Also, a review of the maintenance logbooks for the helicopter did not show any entries regarding malfunctions with the collective control during previous flights, and the helicopter operated normally during the first flight of the day. The pilot stated that he could have chosen to not unplug his helmet and keep his hand on the collective control at all times, which would have prevented the collective from slamming down while he was connecting his radio cables to his helmet. This model helicopter does not have a friction control mechanism on the collective control, and, if it is not held in place by the pilot, it can move up or down during flight. It is likely that, when the pilot removed his hand from the collective control and was distracted with plugging in his helmet radio connection, the collective moved to the full-down position and that he did not have enough altitude to recover the helicopter. ## Factual narrative On September 6, 2013, about 0925 central daylight time, a Continental Copters Inc., OH13-H Tomcat agricultural helicopter, N9005T, registered to Scotts Helicopter Service Inc., of LeSueur, Minnesota, sustained substantial damage after it collided with the ground while maneuvering during an aerial application flight. The pilot was not injured. Visual meteorological conditions prevailed in the vicinity and no flight plan was filed. The aerial application flight was being conducted under the provisions of 14 Code of Federal Regulations Part 137. The flight originated from a private location near Gaylord, Minnesota, about 0920. The pilot reported to work on the morning of the accident for a scheduled day of flying after he had the previous day off. His first aerial application flight of the morning was uneventful and the helicopter landed to reload pesticides. The pilot then took off and successfully applied about 75 gallons pesticides to a field and proceeded to the next field located about 3 miles away at 300-400 feet AGL. While enroute the pilot wanted to call his truck driver over the two way radio. The radio connection to his helmet was unplugged, so he reached and plugged it in with his right hand while his left hand transferred from the collective to the cyclic. The pilot estimated that this process took about 5 to 8 seconds. Immediately after he plugged in the radio connection to his helmet, the collective slammed into a full down position and the pilot recalled seeing his black-colored notebook fly around the cabin due to the sudden collective movement. The pilot then quickly grabbed the collective and raised it up. He noticed that the helicopter was losing altitude and the main rotor RPMs were decreasing, with the engine RPM and main rotor RPM needles split. He recalls twisting the throttle control back and forth with no effect and attempted to autorotate. The helicopter touched down hard, sustaining substantial damage to the tailboom. An on site inspection of the accident site and the helicopter was conducted by an FAA inspector. The inspector reported that no mechanical or environmental anomalies were found that could have contributed to the accident. The pilot stated in the recommendation section of NTSB Form 6120, that could have chose to not unplug his helmet and keep his hand on the collective control at all times, which would have prevented the collective from slamming down while he was connecting his radio cables to his helmet. A review of the maintenance log books for the helicopter did not show any entries regarding malfunctions with the collective control during previous flights and the helicopter was operating normally during the first flight of the day. Additionally, this model helicopter does not have a friction control mechanism on the collective control, and if it is not held in place by the pilot, it could move up or down during flight. ## Aircraft - Registration: [N9005T](https://openairdocs.org/aircraft/N9005T), registered now, S/N CCI-74-1, built 1974 (OpenAirDocs) - Reported make and model: CONTINENTAL COPTERS INC. TOMCAT MK5A - Registry model: [Continental Copters TOMCAT MK5A](https://openairdocs.org/model/continental-copters-tomcat-mk5a) (registry code 2390101) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: CCI-74-1 - Airframe hours: 5734 - Engines: LYCOMING VO-435 SERIES 260 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Scotts Helicopter Services Inc - Registered owner: Scotts Helicopter Services Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, January 3, 2013, 50 hours before - Departed: Arlington, MN - Destination: Arlington, MN ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 27; injuries: minor; commercial; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review May 12, 2012; seat: center; restraint: 3-point; flight hours: 901 total, 700 in this make and model, 851 as pilot in command, 308 in the last 90 days, 155 in the last 30 days, 12 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 160° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: 9,500 ft overcast - Temperature: 72 °F, dew point 86 °F - Altimeter: 30.05 inHg - Observed at: NWS, 9 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 20130906017709A](https://openairdocs.org/incident/20130906017709A), Sep 6, 2013: Continental Copters Inc. TOMCAT MK5A, Arlington, MN, Substantial damage. According to the pilot's statement, while transitioning between fields in level cruise at between 300' and 400' AGL, the pilot transferred his left hand to the… ## Other investigations on N9005T (2) 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. - [NTSB CEN18LA300](https://openairdocs.org/ntsb/CEN18LA300), Jul 27, 2018: Continental Copters Tomcat MK5A (N9005T), Le Sueur, MN, substantial damage. Probable cause: The pilot's inadequate preflight and in-flight fuel planning, during which he did not visually check the fuel quantity in the fuel tanks and instead relied on the fuel gauges that were showing… - [NTSB CHI97LA306](https://openairdocs.org/ntsb/CHI97LA306), Sep 30, 1997: Bell 47 (N9005T), Pipestone, MN, substantial damage. Probable cause: the fracture of the pitch control rod assembly. ## Docket (3 files) The files NTSB released with the investigation on February 3, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=88009. 3.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40409757&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Statement (item 2, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40409758&FileExtension=.PDF&FileName=Pilot%20Statement-Master.PDF - Annual Inspection Documentation (item 3, .PDF, 156 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40409762&FileExtension=.PDF&FileName=Annual%20Inspection%20Documentation-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.