19991007028969A

Accident · Substantial damage

FAA accident report · Airtrc AT-502B · Bay City, TX · October 7, 1999

Date
October 7, 1999 · 16:20 local
Place
Bay City, TX
Phase of flight
Low Level Operations
Operating rules
Agricultural (Part 137)
Operator
XU9G
Damage
Substantial damage
Aircraft
N61768
NTSB investigation
NTSBFTW00LA008
Reported as
Airtrc AT502B
Reported engine
Pratt & Whitney PT6A34AG
Fatal injuries
0
Pilot’s flight hours
20,000 total6,000 in this make and model50 in the last 90 days

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

(.19) On October 7, 1999, at 1620 central daylight time, an air tractor AT-502B airplane, N61768, owned and operated by aviation services unlimited of Bay City, Texas, was substantially damaged when it impacted terrain while maneuvering near Bay City, Texas. The commercial pilot, sole occupant, received minor injuries. Visual meteorological conditions prevailed and a flight plan was not filed for the 14 code of federal regulations part 137 aerial application flight. The flight originated from a private grass airstrip about 30 minutes prior to the accident. During a telephone interview, conducted by the NTSB investigator-in-charge, the pilot stated that he had completed his 8th pass over the field and was turning to make the 9th pass. He was in a 60 degree bank at approximately 300 feet AGL, when he "flew through the wake turbulence from his previous pass and stalled the airplane." The airplane "violently rolled to the right, then to the left." Before he could recover from the stall, the pilot leveled the airplane and impacted the ground. The airplane initially impacted the ground with the right main landing gear and right wing tip, separating the right main landing gear fro m the airframe. The airplane bounced up and impacted a second time with the left main landing gear, left wing tip, and tail section. The tail section was structurally damaged and remained partially attached to the fuselage, the left main landing gear collapsed, and both wings sustained structural damage. (-23) the agricultural application pilot stated that he had completed his 8th pass over the field and was in a 60 degree bank at approx. 3000 feet AGL when he flew through the wake turbulence from his previous pass and stalled the aiplane. The pilot said the airplane "violently rolled to the right, then to the left". The pilot said that before he could recover from the stall the airplane impacted the ground with the right wing tip and right main landing gear. The airplane then bounced with the tail section, propeller, and left main landing gear. Substantial damage to the a/c and a superficial injury to the pilot. (.4)the pilot completed the 8th seeding pass over a field and was turning to make the 9th pass when the agricultural airplane shuddered and made three uncommanded banks prior to impacting the terrain. The pilot initially stated that he flew through his own wake turbulence and stalled the airplane while in a 60-degree bank to the right. However, the pilot later stated that he thought the propeller may have malfunctioned resulting in the loss of airplane control. Post-accident examination of the airplane flight controls and the propeller revealed no anomalies that would have prevented normal operation of the aircraft prior to the accident.

As the FAA filed it

(.19) ON OCTOBER 7, 1999, AT 1620 CENTRAL DAYLIGHT TIME, AN AIR TRACTOR AT-502B AIRPLANE, N61768, OWNED AND OPERATED BY AVIATION SERVICES UNLIMITED OF BAY CITY, TEXAS, WAS SUBSTANTIALLY DAMAGED WHEN IT IMPACTED TERRAIN WHILE MANEUVERING NEAR BAY CITY, TEXAS. THE COMMERCIAL PILOT, SOLE OCCUPANT, RECEIVED MINOR INJURIES. VISUAL METEOROLOGICAL CONDITIONS PREVAILED AND A FLIGHT PLAN WAS NOT FILED FOR THE 14 CODE OF FEDERAL REGULATIONS PART 137 AERIAL APPLICATION FLIGHT. THE FLIGHT ORIGINATED FROM A PRIVATE GRASS AIRSTRIP ABOUT 30 MINUTES PRIOR TO THE ACCIDENT. DURING A TELEPHONE INTERVIEW, CONDUCTED BY THE NTSB INVESTIGATOR-IN-CHARGE, THE PILOT STATED THAT HE HAD COMPLETED HIS 8TH PASS OVER THE FIELD AND WAS TURNING TO MAKE THE 9TH PASS. HE WAS IN A 60 DEGREE BANK AT APPROXIMATELY 300 FEET AGL, WHEN HE "FLEW THROUGH THE WAKE TURBULENCE FROM HIS PREVIOUS PASS AND STALLED THE AIRPLANE." THE AIRPLANE "VIOLENTLY ROLLED TO THE RIGHT, THEN TO THE LEFT." BEFORE HE COULD RECOVER FROM THE STALL, THE PILOT LEVELED THE AIRPLANE AND IMPACTED THE GROUND. THE AIRPLANE INITIALLY IMPACTED THE GROUND WITH THE RIGHT MAIN LANDING GEAR AND RIGHT WING TIP, SEPARATING THE RIGHT MAIN LANDING GEAR FRO M THE AIRFRAME. THE AIRPLANE BOUNCED UP AND IMPACTED A SECOND TIME WITH THE LEFT MAIN LANDING GEAR, LEFT WING TIP, AND TAIL SECTION. THE TAIL SECTION WAS STRUCTURALLY DAMAGED AND REMAINED PARTIALLY ATTACHED TO THE FUSELAGE, THE LEFT MAIN LANDING GEAR COLLAPSED, AND BOTH WINGS SUSTAINED STRUCTURAL DAMAGE. (-23) THE AGRICULTURAL APPLICATION PILOT STATED THAT HE HAD COMPLETED HIS 8TH PASS OVER THE FIELD AND WAS IN A 60 DEGREE BANK AT APPROX. 3000 FEET AGL WHEN HE FLEW THROUGH THE WAKE TURBULENCE FROM HIS PREVIOUS PASS AND STALLED THE AIPLANE. THE PILOT SAID THE AIRPLANE "VIOLENTLY ROLLED TO THE RIGHT, THEN TO THE LEFT". THE PILOT SAID THAT BEFORE HE COULD RECOVER FROM THE STALL THE AIRPLANE IMPACTED THE GROUND WITH THE RIGHT WING TIP AND RIGHT MAIN LANDING GEAR. THE AIRPLANE THEN BOUNCED WITH THE TAIL SECTION, PROPELLER, AND LEFT MAIN LANDING GEAR. SUBSTANTIAL DAMAGE TO THE A/C AND A SUPERFICIAL INJURY TO THE PILOT. (.4)THE PILOT COMPLETED THE 8TH SEEDING PASS OVER A FIELD AND WAS TURNING TO MAKE THE 9TH PASS WHEN THE AGRICULTURAL AIRPLANE SHUDDERED AND MADE THREE UNCOMMANDED BANKS PRIOR TO IMPACTING THE TERRAIN. THE PILOT INITIALLY STATED THAT HE FLEW THROUGH HIS OWN WAKE TURBULENCE AND STALLED THE AIRPLANE WHILE IN A 60-DEGREE BANK TO THE RIGHT. HOWEVER, THE PILOT LATER STATED THAT HE THOUGHT THE PROPELLER MAY HAVE MALFUNCTIONED RESULTING IN THE LOSS OF AIRPLANE CONTROL. POST-ACCIDENT EXAMINATION OF THE AIRPLANE FLIGHT CONTROLS AND THE PROPELLER REVEALED NO ANOMALIES THAT WOULD HAVE PREVENTED NORMAL OPERATION OF THE AIRCRAFT PRIOR TO THE ACCIDENT.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.