ATL98LA115

NTSB accident investigation · Schweizer G164B · Newton, MS · August 16, 1998

Accident · No injuriesLimited investigationFinal report
Date
August 16, 1998, 16:15 local (21:15 UTC)
Place
Newton, MS
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N7502ASchweizer G164B
Weather
Visual (VMC) · Day
Status
Completed · report July 26, 2001
Report
Approved by Office Director
FAA report
19980816021119A
Case key
43650

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

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Probable cause

The erosion of the compressor impeller and the unsecured fuel control unit resulted in the loss of engine power during the initial climb.

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 power(partial) - mech failure/malfTakeoff - initial climb
Compressor assembly,impeller - erodedCause
Fuel system,fuel control - not securedCause
Forced landingDescent - emergency
In flight collision with objectDescent - emergency
Object - tree(s)

Analysis

According to the pilot, he was conducting agricultural operations and had dispensed approximately 13 loads of agricultural products. While preparing for another takeoff, the pilot noticed that the engine was slow to spool up to 100%. During climb-out the pilot noticed that he did not have enough power to maintain the climb. The pilot pushed the throttle full forward, dumped his load, and he could not arrest his descent. The airplane collided with trees as the pilot executed a forced landing. Examination of the engine assembly disclosed that the first stage compressor wheel displayed evidence of erosion. There was fresh dirt and debris in the first stage compressor assembly. Several stator vanes exhibited pre-impact bending associated with erosion. Further examination of the engine assembly disclosed that the fuel control unit rear support bracket bolt was not installed on the fuel control unit. The engine post-accident examination disclosed that the fuel control unit was displaced approximately 1/4 inch from the normally installed position. Examination of the fuel control unit showed chaffing on the pump flange.

Factual narrative

On August 16, 1998, at 1615 Central Daylight Time, a Schweizer, G164B, N7502A, collided with trees, when altitude could not be maintained due to loss of engine power, near Newton, Mississippi. The aerial application flight was operated by Payne Flying Service under the provisions of Title 14 CFR Part 137, no flight plan was filed. Visual meteorological conditions prevailed at the time of the accident. The commercial pilot was not injured. The airplane was substantially damaged. The flight departed Newton Mississippi, at 1613.

According to the pilot, he had been conducting agricultural operations and had dispensed approximately 13 loads of agricultural products. He was preparing for takeoff when he noticed that the engine was slow to spool up, but the run-up was otherwise normal with the engine operating at 100%. During climb-out the pilot noticed that he did not have enough power to maintain the climb, he pushed the throttle full forward, and dumped his load. Despite the pilot's efforts to regain full power, engine power continued to decrease, and he could not arrest the descent. The pilot selected an area for a forced landing. The airplane collided with trees during the attempted forced landing.

Examination of the engine assembly disclosed that the first stage compressor wheel displayed evidence of erosion. There was also fresh dirt and debris on the first stage compressor assembly. Several stator vanes exhibited pre-impact bending associated with erosion (see attached engine examination report). Further examination of the engine assembly disclosed that the fuel control unit rear support bracket bolt was not installed on the fuel control unit. The post-accident examination disclosed that the fuel control unit was displaced approximately 1/4 inch from the normally installed position. Examination of the fuel control unit showed chaffing on the pump flange.

According to operator's maintenance records, the engine was last inspected 128 hours before the accident. The engine had accumulated 6000 hours of operation since the last overhaul.

Aircraft

Registration
N7502A
Reported as
Schweizer G164B
Category
Airplane
Serial number
797B
Airframe hours
6,552
Engine
Bristol TPE-331-6-252, 715 horsepower, turbo prop
Damage
Substantial damage
Flight
Aerial application · Part 137
Registered owner
Darrell W. Meredith
Airworthiness certificate
Special, Restricted (Special)
Last inspection
100 hour · July 15, 1998 · 144 hours before

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
43
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Center
Flight hours
5,485 total · 2,000 in this make and model · 5,400 as pilot in command · 68 in the last 90 days · 68 in the last 30 days · 10 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
82 °F, dew point 73 °F
Altimeter
29.00 inHg
Observed at
MEI, 30 nm away

FAA reports on this event · 1

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

Other investigations on N7502A · 2

Matched to the same aircraft by N-number and date.