FTW03LA099

NTSB accident investigation · Robinson R22 Beta II · Kent, TX · February 18, 2003

Accident · Minor injuriesLimited investigationFinal report
Date
February 18, 2003, 13:23 local (19:23 UTC)
Place
Kent, TX
Injuries
1 minor, 1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N54TRRobinson R22 Beta II
Weather
Visual (VMC) · Day
Status
Completed · report June 30, 2004
Report
Approved by Office Director
Parties
Federal Aviation Administration, SW01
FAA report
20030218003369A
Case key
56506

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The loss of main rotor drive due to a drive belt separation resulting in a forced landing. A contributing factor was the lack of suitable terrain for the forced landing.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Airframe/component/system failure/malfunctionCruise
Rotor drive system,main rotor drive belt - separationCause
Forced landingDescent - emergency
Autorotation - performedPilot in command
Hard landingEmergency landing
Flare - inadequate
Misc rotorcraft,tail boom - separation
Terrain condition - none suitableFactor
Terrain condition - rough/uneven
Terrain condition - high vegetation

Analysis

While ferrying a helicopter to its new owner/operator, the 1,351-hour pilot experienced a loss of main rotor drive. The pilot reported that the helicopter was in level cruise flight at an altitude of 700 to 900 feet AGL at an indicated airspeed of 70 to 75 knots, when they heard a loud "thump" coming from the area behind the cabin, immediately followed by the activation of the clutch light and accompanied with a change in engine and rotor noise. Within a couple of seconds, the pilot reported hearing another "thump" and, subsequently, the engine RPM started to increase as the rotor RPM was decreasing. The pilot initiated a 180-degree turn to position the helicopter into the wind while maintaining 70 knots as he entered an autorotation into rolling rough and uneven terrain. The helicopter came to rest in an upright position. Examination of the wreckage by the FAA inspectors, who traveled to the accident site, revealed that both main rotor blades were damaged and the tailboom was severed from the helicopter and broken into several pieces consistent with the main rotor contacting the tailboom during the landing. The engine showed evidence of an overspeed greater than about 110%. One of the two drive belts was missing and the remaining belt was off of the upper sheave and showed considerable damage. The wreckage was recovered to the Robinson Helicopter Company facility in Torrance, California, for a detailed examination. No discrepancies were noted, apart from impact related damage, in the assembly, installation or alignment of the engine, clutch assembly or actuator assembly. No evidence of pre-impact damage to the flight and powerplant controls was found. The failed belt was found separated between the vees with only a 5-inch section still intact.

Factual narrative

On February 18, 2003, at 1323 central standard time (CST), a Robinson R22 Beta II helicopter, N54TR, was substantially damaged during a hard landing following a loss of main rotor drive near Kent, Texas. The helicopter was registered to the Robinson Helicopter Company of Torrance, California; however, it was pending title transfer to its new owner/operator, Executive Helicopters of Vega Baja, Puerto Rico. The commercial pilot was not injured and his pilot rated passenger sustained minor injuries. The helicopter was being operated under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed throughout the area for the ferry flight for which a flight plan was not filed. The ferry flight originated at Torrance, California, and was destined for the new owner's facility near San Juan, Puerto Rico. The flight's last refueling stop was made at the West Texas Airport (T27) near El Paso, Texas, with the Fort Stockton Airport (FST) near Fort Stockton, Texas, as the next intended fuel stop. The helicopter departed El Paso with 23 gallons of 100LL aviation fuel on board for the 177-nautical mile flight to Fort Stockton.

The pilot reported that the helicopter was in level cruise flight at an altitude of 700 to 900 feet AGL at an indicated airspeed of 70 to 75 knots, when they heard a loud "thump" coming from the area behind the cabin, immediately followed by the activation of the clutch light and accompanied with a change in engine and rotor noise. Within a couple of seconds, the pilot reported hearing another "thump" and, subsequently, the engine RPM started to increase as the rotor RPM was decreasing. The pilot initiated a 180-degree turn to position the helicopter into the wind while maintaining 70 knots as he entered an autorotation. Following the landing flare to rough and down-sloping terrain, the helicopter landed hard, the nose pitched forward and the main rotor severed the tailboom.

The pilot reported, in his statement, that they were "well aware of the limitations of the helicopter as well as of the environmental conditions of the southwestern states." All of the supporting maintenance publications for the helicopter, the ground handling wheels and any other non-essential items were shipped to Puerto Rico in order to remain within the weight and balance limits of the helicopter. Both pilots had completed the Robinson Helicopter Company Operator's Safety Course at Torrance the week prior to the accident.

The pilot held a commercial pilot certificate with helicopter and helicopter instructor ratings. Per the logbook, the pilot had accumulated a total of 1,351 flight hours, 1,230 hours of which were in this make and model of helicopter. In the last 90 days, the pilot had accumulated a total of 114 flight hours, 94 hours of which were in this make and model. The pilot's second-class medical certificate issued on January 3, 2003 listed no restrictions.

The second pilot held a private pilot certificate with single engine land and helicopter ratings. Per the logbook, the second pilot had accumulated a total of 295 hours, 75 of which were in this make and model. In the last 90 days, the second pilot had accumulated a total of 33 hours, 27 of which were in this make and model. The second pilot's third-class medical certificate issued on August 16, 2001 listed the restriction that he wear prescription lenses.

The Robinson model R22 Beta II helicopter (S/N 3412) has a two-bladed main rotor, a two-bladed tail rotor and is powered by a Lycoming O-320-J2A reciprocating engine (S/N L-38934-36A) derated to 145 horsepower.

A review of the maintenance records revealed that the helicopter and engine had accumulated a total of 19.9 hours since new.

At 1353 CST, the Fort Stockton automated surface observing system (ASOS), located 80 miles east of the accident site, reported the wind 290 degrees at 12 knots gusting to 19 knots, clear skies, 10 miles visibility, temperature 81 degrees Fahrenheit, dew point 25 degrees Fahrenheit and altimeter 29.94 inches of Mercury.

The helicopter came to rest in an upright position. Examination of the wreckage by the FAA inspectors, who traveled to the accident site, revealed that both main rotor blades were damaged and the tailboom was severed from the helicopter and broken into several pieces consistent with the main rotor contacting the tailboom during the landing. The engine showed evidence of an overspeed greater than about 110%. One of the two drive belts was missing and the remaining belt was off of the upper sheave and showed considerable damage.

The wreckage was recovered and moved to the Robinson Helicopter Company facility in Torrance, California for a more detailed examination. No discrepancies were noted, apart from impact related damage, in the assembly, installation or alignment of the engine, clutch assembly or actuator assembly. No evidence of pre-impact damage to the flight and powerplant controls was found. The drive belts for this helicopter are of a double-vee design. The one recovered belt was cut across the vees for removal. The belt had separated between the vees with only a 5-inch section still intact.

Aircraft

Registration
N54TR
Reported as
Robinson R22 Beta II
Category
Helicopter
Serial number
3412
Airframe hours
19.9
Engine
Lycoming O-360-J2A, 145 horsepower, reciprocating
Damage
Substantial damage
Flight
Ferry · Part 91
Operator
Robinson Helicopters Company
Registered owner
Executive Helicopter
Airworthiness certificate
Standard, Normal
Departed
T27 · El Paso, TX
Destination
FST · Fort Stockton, TX

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
40
Injuries
None
Certificates
Flight instructor, Commercial
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
June 1, 2001
Seat
Right
Flight hours
1,351 total · 1,230 in this make and model · 1,255 as pilot in command · 114 in the last 90 days · 57 in the last 30 days · 10 in the last 24 hours
Role
Co-pilot
Age
35
Injuries
Minor
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Seat
Left
Flight hours
295 total · 75 in this make and model · 195 as pilot in command · 33 in the last 90 days · 24 in the last 30 days · 11 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
290° at 12 knots, gusting 19
Visibility
10 statute miles
Lowest ceiling
None
Temperature
27 °F, dew point -4 °F
Altimeter
29.94 inHg
Observed at
KFST, 67 nm away

Docket · 3

The files NTSB released with the investigation on April 26, 2004, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.4 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.