Individually Owned: 150,657
Corporate Owned: 137,281
Zephyrhills Municipal Airport
Aircraft Accident/Incident Report
Zephyrhills, Florida 33540
Saturday, October 19, 2013 11:32 EDT
NTSB Narrative Summary Released at Completion of Accident
The pilot reported that, while in the traffic pattern at his home airport practicing touch-and-go landings, the experimental, amateur-built airplane experienced a complete loss of thrust from the propeller. While turning from the crosswind leg of the traffic pattern onto the downwind leg of the traffic pattern, the engine suddenly “overreved.” The pilot reduced power and chose to perform an emergency landing. He then tried adding power, but the propeller did not respond and was windmilling. He established best glide speed, but the airplane had developed a high sink rate and was losing altitude rapidly. He then slowed the airplane as it approached a set of powerlines. The airplane clipped one of the powerlines, which nearly severed the left wing. The pilot then “stalled” the airplane and touched down hard. The airplane was substantially damaged during the forced landing.
Examination of the engine revealed that a belt-driven propeller speed reduction unit (PSRU) was installed. Further examination revealed that both drive belts from the PSRU were broken into several pieces, and shredded material from the belts was present throughout the engine compartment. Small pieces of rubber were also present on the forward part of the engine, the propeller hub assembly, and the PSRU pulleys’ grooves. Examination of the broken belts revealed jagged belt fractures and evidence of overheating, hardening, back cracks, land area wear, and “V” rib wear, all of which is indicative of inadequate belt tension, which can cause the belts to slip as they travel around the pulleys and generate heat buildup. The heat buildup can cause the rubber compounds in the belt to break down and crack and lead to a belt failure. According to maintenance records, the drive belts for the PSRU had been replaced about 20 hours of operation before the accident flight.
NTSB Probable Cause Narrative
The failure of the propeller speed reduction unit drive belts due to inadequate belt tension being applied during installation, which resulted in a complete loss of thrust.
Event Information
| Type of Event | Accident |
| Event Date | 10/19/2013 |
| Event Day of the Week | Saturday |
| Time of Event | 1132 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Zephyrhills |
| Event State | FLORIDA |
| Event Country | -- |
| Zipcode of the event site | 33540 |
| Event Date Year | 2013 |
| Event Date Month | 10 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 281341N |
| Event Location Longitude | 0820921W |
| Event Location Airport | Zephyrhills Municipal Airport |
| Event Location Nearest Airport ID | ZPH |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 2 |
| Degrees magnetic from airport | 300 |
| Airport Elevation | 90 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1135 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 300 |
| Weather Observation Facility ID | ZPH |
| Elevation of weather observation facility | 90 |
| Distance of event from weather observation facility (units?) | 2 |
| Time Zone of the weather observation | EDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 9500 |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | -- |
| Sky Condition for Lowest Ceiling | Overcast |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 28 |
| Dew Point at event time (in degress fahrenheit) | 21 |
| Wind Direction (degrees magnetic) | 190 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 4 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.98 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 33141 |
| NTSB Notification Source | FAA Southern C-ROC |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Aug 21 2014 1:04PM |
| User who most recently changed record | kenj |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N538HB |
| NTSB Number | ERA14LA004 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | MCDONALD HOWARD BRIAN |
| Aircraft Model | ZENAIR 701 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 1001 |
| Certified Max Gross Weight | 1100 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | Yes |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | 1 |
| Total number of seats on the aircraft | 2 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Conditional |
| Date of Last Inspection | Sep 10 2013 12:00AM |
| Airframe hours since last inspection | 20 |
| Airframe Hours | 43 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | MCDONALD HOWARD BRIAN |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | OAK HILL |
| Aircraft Owner State | OH |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 45656-9510 |
| Operator is an individual? | Yes |
| Operator Name | Timothy W. Williamson |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | -- |
| Operator City | Thonotassa |
| Operator State | FL |
| Operator Country | USA |
| Operator Zip code | 33592 |
| 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) | Personal |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | Yes |
| Departure Airport Code | ZPH |
| Departure City | Zephyrhills |
| Departure State | FL |
| Departure Country | USA |
| Departure Time | 1100 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | ZPH |
| Destination City | Zephyrhills |
| Destination State | FL |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Aug 21 2014 1:08PM |
| User who most recently changed record | kenj |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 22 |
| Runway Length | 4999 |
| Runway Width | 100 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |