# NTSB DFW07LA118: Grumman American AA-5B, N28730, Hilltop Lakes, TX, May 20, 2007 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 20, 2007, 15:00 local (20:00 UTC) - Place: Hilltop Lakes, TX - Coordinates: 31.029985, -96.109199 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.0300&lon=-96.1092&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed, report July 25, 2007 - Report: Approved by Office Director - Parties: FAA FSDO Houston, Texas - NTSB case key (mKey): 65822 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW07LA118 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65822/pdf - Page: https://openairdocs.org/ntsb/DFW07LA118 ## Probable cause The loss of engine power due to carburetor ice. Contributing factors were the lack of suitable terrain for a forced landing and the weather conditions that were conducive to carburetor ice. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, approach - fuel system,carburetor - ice (cause) - carburetor heat control - not activated (contributing factor) - Loss of control - in flight, descent - uncontrolled - In flight collision with object, descent - uncontrolled - altitude/clearance - not maintained, pilot in command (contributing factor) ## Analysis The 300-hour private pilot reported that the airplane entered an un-commanded nose down pitch and banked to the left while the airplane was established on final approach to runway 16. The pilot and passenger were seriously injured. An examination of the engine was conducted. Examination of the engine 180-horsepower engine did not reveal any mechanical anomalies that could have prevented normal engine operation. The fuel cells were breached; however, the operator reported that the airplane departed the airport with a full load of fuel, and according to the engine tach, the flight's duration was 36 minutes. According to icing probability chart, the weather conditions at the time of the accident were favorable for the probability of "serious" carburetor icing at glide power. Examination of the airplane and engine revealed that the carburetor heat control was in the "off" or "cold" position. The pilot and passenger were seriously injured. Weather reported 30 miles south of the accident site at the time of the accident stated winds were from 120 degrees at 9 knots gusting to 14 knots. ## Factual narrative On May 20, 2007, approximately 1500 central daylight time, a single-engine Grumman American AA-5B airplane, N28730, was substantially damaged when it collided with trees following a loss of control while on approach to the Hilltop Lakes Airport (0TE4), near Hilltop Lakes, Texas. The private pilot and his passenger were seriously injured. The airplane was registered to Cyrus Aviation Services, Inc., of Bryan, Texas, and was being operated by the pilot. Visual meteorological conditions prevailed and no flight plan was filed for the 14 Code of Federal Regulations Part 91 personal flight. The cross-country flight originated from the Coulter Field Airport (KCFD) near Bryan, Texas, at 1330. The 300-hour private pilot reported that while on final approach to Runway 16 at the Hilltop Lakes Airport, the airplane entered an un-commanded nose down pitch and banked to the left. The pilot added that he responded by applying full power and adding back pressure; however the airplane did not respond and crashed into the trees. The airplane came to rest suspended in the trees. Members of the local volunteer fire department removed trees to gain access to the airplane and "forcibly opened the canopy." Both occupants were assisted out of the airplane. The airplane was equipped with seat belts and shoulder harnesses. They were both being used at the time of the mishap. According to a Federal Aviation Administration (FAA) inspector, who traveled to the accident site, both wings sustained structural damage. The nose wheel, engine firewall, engine mounts, and portions of the fuselage were also damaged. There was no fire. An examination of the engine was conducted on June 8, 2007 by representatives of the National Transportation Safety Board. Examination of the engine 180-horsepower Lycoming O-360-A4K engine did not reveal any mechanical anomalies that could have prevented normal engine operation. The fuel cells were breached; however, the operator reported that the airplane departed the Coulter Field with a full load of fuel, and according to the engine tach, the flight's duration was 36 minutes. According to the aircraft's performance chart, conditions were favorable for the probability of "serious" carburetor icing at glide power. Examination of the airplane and engine revealed that the carburetor heat control was in the "off" or cold position. At 1453, the weather observation facility at Easterwood Field Airport (CLL), located near College Station, Texas, located 31 miles south of the accident site, reported wind from 120 degrees at 9 knots, gusting to 14 knots, visibility 10 statute miles, a scattered cloud layers at 4,900 feet and 10,000 feet MSL, temperature 81 degrees Fahrenheit, dew point 55 degrees Fahrenheit, and a barometric pressure of 30.07 inches of Mercury. ## Aircraft - Registration: [N28730](https://openairdocs.org/deregistered/N28730-2009-10-28), registration cancelled 2009-10-28, S/N AA5B0781, built 1978 (OpenAirDocs) - Reported make and model: Grumman American AA-5B - Registry model: [Grumman American Avn. AA-5B](https://openairdocs.org/model/grumman-american-avn-aa-5b) (registry code 3960105) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: AA5B0781 - Airframe hours: 3051 - Engines: Lycoming 0-360-a4k 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Justin Smith, doing business as Cyrus Aviation - Registered owner: Cyrus Aviation Services - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, March 1, 2007, 77 hours before - Departed: KCFD, Bryan, TX - Destination: 0TE4, Hilltop Lakes, TX - Airport: 0TE4, Hilltop Lakes Airport, runway 16, 3,000 × 40 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: serious; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review January 1, 2006; seat: left; flight hours: 300 total, 15 in this make and model, 200 as pilot in command, 10 in the last 90 days, 5 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 120° at 9 knots, gusting 14 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 81 °F, dew point 55 °F - Altimeter: 30.06 inHg - Observed at: KCLL, 30 nm away 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.