# NTSB MIA03LA181: Schweizer 269C-1, N6147Q, Homestead, FL, September 11, 2003 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: September 11, 2003, 14:45 local (18:45 UTC) - Place: Homestead, FL - Coordinates: 25.498611, -80.554168 - Nearby events: https://openairdocs.org/map.md?lat=25.4986&lon=-80.5542&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report August 3, 2006 - Report: Approved by Office Director - Parties: Schweizer Aircraft Corporation, FAA Flight Standards District Office - NTSB case key (mKey): 57948 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA03LA181 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/57948/pdf - Page: https://openairdocs.org/ntsb/MIA03LA181 ## Probable cause the inadequate 100-hour inspection of the helicopter by other maintenance personnel who failed to discover that the landing gear dampers had low pressure, which resulted in ground resonance and subsequent substantial damage during a run-on landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Miscellaneous/other, landing - landing gear,main gear shock absorbing strut - low pressure - maintenance,100-hour inspection - inadequate, other maintenance personnel (cause) - run on landing - performed, pilot in command(cfi) - ground resonance - encountered, pilot in command(cfi) ## Analysis The certified flight instructor (CFI) stated that after departure the flight proceeded to the Homestead General Airport where he advised the student that the lesson would continue with "running landing" and "running take off" training from the previous day. The flight continued in the traffic pattern for runway 36, and when on short final approach to the runway at 5 feet above ground level, the helicopter was at 25 knots indicated airspeed. The helicopter contacted the runway with the skids parallel to the runway centerline, and the CFI allowed the helicopter to continue sliding. The CFI advised the student that the lesson would conclude with a "running takeoff", and upon lifting off the runway at an indicated airspeed of 35 knots, he noticed a vibration from the main rotor system. He noticed the rpm was decreasing and touched down again on the runway, at which time the helicopter began to "shake violently." He realized the flight had encountered ground resonance, and noticed that there was insufficient main rotor rpm to lift off the ground to stabilize the vibrating rotor blade system. He lowered the collective but felt a force when he attempted to reduce throttle input; he felt the force was the student pilot applying throttle input. At that point he was contacted in the head, lost consciousness, which he regained in the hospital. The student pilot advised a Federal Aviation Administration (FAA) inspector that when the flight was approximately 30 feet above ground level prior to performing a running landing, the CFI took the controls from him. The flight continued and while sliding on the runway, the CFI started screaming and froze on the controls. He (student pilot) then braced for impact. Following recovery of the helicopter, the landing gear and main rotor dampers were removed for further examination at the manufacturer's facility with FAA oversight. Examination of the main rotor blade dampers revealed all three exhibited damage associated from lead lag motions encountered in ground resonance. Examination of the four landing gear dampers which had been installed when the helicopter was manufactured revealed all tested out of limits for charge pressure (low). The helicopter was last inspected in accordance with a 100-Hour inspection on August 11, 2003; the helicopter had accumulated 87.9 hours since the inspection at the time of the accident. Review of the 100-Hour inspection guide revealed the landing gear dampers are required to be inspected for operation and condition, and for damper extension with a full fuel tank. Review of Section 12 of the Basic Handbook of Maintenance Instructions manual indicates the landing gear dampers will experience a decrease in pressure with subsequent use of the helicopter, and they should be extension checked during a 100-Hour inspection, or every six months, whichever occurs first. According to a memorandum from the Director of Flight Training to all flight instructors dated August 25, 2003, with respect to the Dominican Republic Flight Training Program, running landings were prohibited to be demonstrated and practiced until a new order was given. ## Factual narrative On September 11, 2003, about 1445 eastern daylight time, a Schweizer 269C-1, N6147Q, registered to Caribbean Helicopter Leasing, Inc., operated by Helicenter International Academy, was substantially damaged during a run-on landing at the Homestead General Aviation Airport, Homestead, Florida. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 instructional flight from the Kendall-Tamiami Executive Airport, Miami, Florida, to the Homestead General Aviation Airport, Homestead, Florida. The certified flight instructor (CFI) and student sustained minor injuries. The flight originated at 1430, from the Kendall-Tamiami Executive Airport. The CFI stated that after departure the flight proceeded to the Homestead General Airport where he advised the student that the lesson would continue with "running landing" and "running take off" training from the previous day. The flight continued in the traffic pattern for runway 36, and when on short final approach to the runway at 5 feet above ground level, the helicopter was at 25 knots indicated airspeed. The helicopter contacted the runway with the skids parallel to the runway centerline, and the CFI allowed the helicopter to continue sliding. The CFI advised the student that the lesson would conclude with a "running takeoff", and upon lifting off the runway at an indicated airspeed of 35 knots, he noticed a vibration from the main rotor system. He noticed the rpm was decreasing and touched down again on the runway, at which time the helicopter began to "shake violently." He realized the flight had encountered ground resonance, and noticed that there was insufficient main rotor rpm to lift off the ground to stabilize the vibrating rotor blade system. He lowered the collective but felt a force when he attempted to reduce throttle input; he felt the force was the student pilot applying throttle input. At that point he was contacted in the head, lost consciousness, which he regained in the hospital. The student pilot advised a Federal Aviation Administration (FAA) inspector that when the flight was approximately 30 feet above ground level prior to performing a running landing, the CFI took the controls from him. The flight continued and while sliding on the runway, the CFI started screaming and froze on the controls. He (student pilot) then braced for impact. Following recovery of the helicopter, the landing gear and main rotor dampers were removed for further examination at the manufacturer's facility with FAA oversight. Examination of the main rotor blade dampers revealed all three exhibited damage associated from lead lag motions encountered in ground resonance. Examination of the four landing gear dampers which had been installed when the helicopter was manufactured revealed all tested out of limits for charge pressure (low). The helicopter was last inspected in accordance with a 100-Hour inspection on August 11, 2003; the helicopter had accumulated 87.9 hours since the inspection at the time of the accident. Review of the 100-Hour inspection guide revealed the landing gear dampers are required to be inspected for operation and condition, and for damper extension with a full fuel tank. Review of Section 12 of the Basic Handbook of Maintenance Instructions manual indicates the landing gear dampers will experience a decrease in pressure with subsequent use of the helicopter, and they should be extension checked during a 100-Hour inspection, or every 6 months, whichever occurs first. According to a memorandum from the Director of Flight Training to all flight instructors dated August 25, 2003, with respect to the Dominican Republic Flight Training Program, running landings were prohibited to be demonstrated and practiced until a new order was given. The helicopter minus the retained main rotor and landing gear dampers was released to the president and CEO of the owner of the helicopter on November 18, 2003. The retained main rotor and landing gear dampers were released to the president and CEO of the owner of the helicopter on March 23, 2004. ## Aircraft - Registration: [N6147Q](https://openairdocs.org/deregistered/N6147Q-2018-01-25), registration cancelled 2018-01-25, S/N 0068, built 1997 (OpenAirDocs) - Reported make and model: Schweizer 269C-1 - Registry model: [Schweizer 269C-1](https://openairdocs.org/model/schweizer-269c-1) (registry code 8059504) (OpenAirDocs) - Registry engine: [Lycoming HO-360 series](https://openairdocs.org/engine/lycoming-ho-360-series) (registry code 41513, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 0068 - Airframe hours: 3150.5 - Engines: Lycoming HO-360-C1A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Helicenter International Academy - Registered owner: Caribbean Helicopter Leasing, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, August 11, 2003, 87.9 hours before - Departed: KTMB, Miami, FL - Destination: X51, Homestead, FL - Airport: X51, Homestead General Aviation, runway 36, 4,000 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 32; injuries: minor; commercial, flight instructor; medical: class 2, valid medical--w/ waivers/lim; last flight review August 5, 2003; seat: left; flight hours: 218 total, 25 in this make and model, 25 in the last 90 days, 25 in the last 30 days, 4 in the last 24 hours - Student pilot; age 20; injuries: minor; student; medical: class 3, valid medical--no waivers/lim.; seat: right; flight hours: 17 total, 17 in this make and model, 17 in the last 90 days, 17 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 91 °F, dew point 73 °F - Altimeter: 29.93 inHg - Observed at: KTMB ## 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 20030911023439A](https://openairdocs.org/incident/20030911023439A), Sep 11, 2003: Hughes 269C1, Homestead, FL, Destroyed. (-23) 09-11-03 - Arrived at Homestead general airport (X51) at 1710 hours on September 11, 2003, to investigate a crash involving a Schweizer rotorcraft, model… 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.