Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
San Antonio, Texas 78216
Thursday, February 19, 2004 2:45 CST
NTSB Narrative Summary Released at Completion of Accident
The 493-hour pilot reported that approximately 5 minutes after departure, he noticed a "slight change in engine noise." Subsequently, he heard a "bang," followed by an aural engine warning horn, and a loss of engine power. The pilot initiated an autorotation, and during the autorotation, the helicopter impacted power lines, landed hard on a parking lot surface and came to rest upright. A witness located adjacent to the helicopter's flight path reported hearing a "loud backfire" followed by subsequent white smoke coming from the helicopter. Review of the aircraft maintenance records revealed the engine was overhauled approximately 295 hours prior to the accident. During the engine overhaul, the impeller travel (bump clearance) was measured to be approximately .010 inches. During the engine teardown examination, prior to the removal of the compressor rotor from the rear support, the impeller travel (bump clearance) was measured to be approximately 0.021 inches. The third, fifth, and sixth stage vane assemblies were bent in the direction of rotation. Corresponding damage was observed on the trailing edges of the blades on the adjacent forward compressor rotors. Fretting and score marks noted on the compressor assembly components were consistent with axial movement at the compressor assembly resulting in contact between the compressor blades and vanes, and a subsequent compressor stall and loss of engine power.
NTSB Probable Cause Narrative
The loss of engine power due to the axial movement of the compressor rotor blades contacting the compressor vanes resulting in a subsequent compressor stall. A contributing factor was the improper assembly of the compressor section during the engine overhaul by unknown maintenance personnel.
Event Information
| Type of Event | Accident |
| Event Date | 2/19/2004 |
| Event Day of the Week | Thursday |
| Time of Event | 245 |
| Event Time Zone | Central Standard Time |
| Event City | San Antonio |
| Event State | TEXAS |
| Event Country | -- |
| Zipcode of the event site | 78216 |
| Event Date Year | 2004 |
| Event Date Month | 2 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 292022N |
| Event Location Longitude | 0982827W |
| Event Location Airport | -- |
| Event Location Nearest Airport ID | -- |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 253 Central Standard Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | SAT |
| Elevation of weather observation facility | 809 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | CST |
| Lighting Conditions | Night |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 11 |
| Dew Point at event time (in degress fahrenheit) | 10 |
| Wind Direction (degrees magnetic) | 190 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 8 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.14 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Minor |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | 2 |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 2 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 16718 |
| NTSB Notification Source | FAA Operations Center |
| NTSB Notification Date | Feb 19 2004 12:00AM |
| NTSB Notification Time | 330 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Dec 7 2004 11:17AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | San Antonio, Texas |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N255TP |
| NTSB Number | FTW04GA076 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Public Use |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Schweizer |
| Aircraft Model | 269D |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 0021 |
| Certified Max Gross Weight | 2550 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 3 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Jan 27 2004 12:00AM |
| Airframe hours since last inspection | 21.3 |
| Airframe Hours | 3621.5 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | San Antonio Police Department |
| Aircraft Owner Street Address | 1110 99th St. |
| Aircraft Owner City | San Antonio |
| Aircraft Owner State | TX |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 78214 |
| Operator is an individual? | No |
| Operator Name | -- |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | -- |
| Operator State | -- |
| Operator Country | -- |
| Operator Zip code | -- |
| Operator Code | -- |
| Owner has at least one certificate | None |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Public Use |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | SSF |
| Departure City | San Antonio |
| Departure State | TX |
| Departure Country | USA |
| Departure Time | 240 |
| Departure Time Zone | CST |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | -- |
| Destination City | -- |
| Destination State | -- |
| Destination Country | -- |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Oct 6 2004 9:58AM |
| User who most recently changed record | CASH |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |