DFW07LA118

NTSB accident investigation · Grumman American AA-5B · Hilltop Lakes, TX · May 20, 2007

Accident · Serious injuriesLimited investigationFinal report
Date
May 20, 2007, 15:00 local (20:00 UTC)
Place
Hilltop Lakes, TX
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N28730Grumman American AA-5B
Weather
Visual (VMC) · Day
Status
Completed · report July 25, 2007
Report
Approved by Office Director
Parties
FAA FSDO Houston, Texas
Case key
65822

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 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

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.

Loss of engine powerApproach
Fuel system,carburetor - iceCause
Carburetor heat control - not activatedFactor
Loss of control - in flightDescent - uncontrolled
In flight collision with objectDescent - uncontrolled
Altitude/clearance - not maintainedPilot in commandFactor

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
Reported as
Grumman American AA-5B
Category
Airplane
Serial number
AA5B0781
Airframe hours
3,051
Engine
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

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

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
67
Injuries
Serious
Certificate
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