LAX02LA034

NTSB accident investigation · Air Tractor AT-401B · Las Vegas, NV · November 30, 2001

Accident · No injuriesLimited investigationFinal report
Date
November 30, 2001, 15:46 local (23:46 UTC)
Place
Las Vegas, NV
Injuries
2 uninjured
Phase of flight
Landing
Aircraft
N9186JAir Tractor AT-401BN139LAAir Tractor AT-402A
Weather
Visual (VMC) · Day
Status
Completed · report June 2, 2004
Report
Approved by Office Director
Parties
Federal Aviation Administration
Case key
53852

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 NTSB’s determination of the probable cause, and any contributing factors.

the failure of the AT-401 pilot to maintain clearance with the AT-402 airplane during landing. Contributing factors were the unreliable communication radio in the AT-401, the AT-401 pilot's continued flight with known communication radio problems, and the glare of the sun.

Analysis

Three airplanes, an AT-401, an AT-402 and an AT-502 were making a cross-country formation flight. Originally, the AT-401 was the lead airplane, the AT-402 was in the number 2 position, and the AT-502 was the trailing airplane. The AT-401 experienced radio communication problems during the flight. When the AT-401 pilot was unable to establish radio communications with air traffic control at the destination airport, he turned the lead over to the AT-502. The AT-401 pilot thought he was to transition to the number 2 position with the AT-402 taking the trail position. The pilot of the AT-402 thought the AT-401 was to take the trail position after the AT-502 assumed the lead, and he was to remain the number 2 airplane in the formation/landing sequence. According to the AT-401 pilot, the transition from base leg to final approach brought his airplane through the glare of the setting sun, and he concentrated on maintaining his relative position to the lead airplane. He landed behind the AT-502 and taxied off the runway. The AT-402 pilot indicated he landed behind the AT-502, and during the roll out, felt his airplane shudder as the AT-401 impacted his vertical stabilizer/rudder, passed over his airplane and landed on the runway ahead of him.

Factual narrative

The factual narrative823 words

On November 30, 2001, at 1546 Pacific standard time, an Air Tractor AT-401B, N9186J, landed on top of an Air Tractor AT-402A, N139LA, on runway 19R at the McCarren International Airport, Las Vegas, Nevada. The AT-402A sustained substantial damage to the rudder, while the AT-401B sustained minor damage. Neither the commercial pilot onboard the AT-401B, or the airline transport pilot onboard the AT-402A were injured. The AT-401B was registered to Southeastern Aerial Corp Service Inc., Fort Pierce, Florida, and the AT-402A was registered to Air Tractor Inc., Olney, Texas. Air Tractor operated both airplanes under the provisions of 14 CFR Part 91. The two airplanes were part of a flight of three airplanes that departed the Olney Municipal Airport, Olney, approximately 0845 en route to Las Vegas, where the airplanes were to be displayed at the National Agricultural Aviation Association's annual convention. Visual meteorological conditions prevailed at the time of the accident, and a flight plan had not been filed for the cross-country flight.

For purposes of this report, the three airplanes will be referred to as the AT-401, AT-402, and AT-502.

According to the AT-401 pilot, the AT-401 was equipped with a "ferry radio package that contained a single com[munication] radio and transponder with encoder." The pilot tested the radio with a radio check over the unicom frequency located at the departure airport. The AT-401 pilot indicated the response to his radio check was, "loud and clear."

The AT-401 pilot experienced a gradual loss of radio communication capability when the flight neared Albuquerque, New Mexico (ABQ). The ABQ approach controller indicated the airplane's communications were, "weak, but readable." The AT-401 pilot could hear the communications from the AT-502 pilot; however, he could not hear any communications from AT-402 pilot. The AT-401 pilot indicated that communications were possible (on a limited basis) when the airplanes were aligned adjacent to each other; however, no communications were possible if the airplanes were in trail.

As the flight of three neared its destination, with the AT-401 in lead, the AT-402 next, and the AT-502 in the trailing position, plans were made to enter Las Vegas' class C airspace. It was determined that if the AT-401 could not establish communications with Las Vegas air traffic control, the AT-502 would take the lead, establish communications for the three airplanes, and take the flight to the runway.

The AT-401 could not establish communications with Las Vegas approach control and the lead was transferred to the AT-502. The AT-401 then took up the number 2 position echelon off the AT-502 right wing. The AT-401 pilot changed radio frequencies, along with the AT-502. The AT-502 pilot relayed to the other pilots the headings assigned by air traffic control.

The AT-401 pilot indicated that as they approached the airport, the sun was low on the horizon and "now a factor in visibility." Approach control had cleared the flight of three to make a left base approach to runway 19R. The AT-401 pilot made visual contact with the number 3 airplane (AT-402), and determined he was "roughly in trail with the lead aircraft, several hundred yards behind."

As as the AT-401 turned from base leg to final, the AT-401's heading passed through the glare of the setting sun. The AT-401 pilot maintained his position relative to the lead aircraft (AT-502). He indicated he followed the lead aircraft onto final, landed behind it, and taxied off the active runway.

According to the AT-402 pilot, he was originally in the number 2 position behind the AT-401; however, when the AT-401 experienced radio communication problems, a plan was made to deal with the situation. The AT-402 pilot indicated that plan "A" would be: if the AT-401 pilot obtained airspace clearance, then the landing order would be the AT-401, followed by the AT-402, and then the AT-502. However, as the radio communications degraded on the AT-401, the plan was changed to plan "B," which had the AT-502 obtain the clearance and land, followed again by the AT-402, then the AT-401. The AT-402 remained in the number 2 position in both plans.

The AT-402 pilot indicated he landed number 2 behind the AT-502, and was rolling out with all wheels firmly on the ground, when he felt the aircraft shudder. He observed both main wheels of the AT-401 "come past the cockpit, flying exactly over the top of me." The AT-401 was flying straight and level and landed ahead of the AT-402. The AT-402 pilot scanned his instrument panel, powered up, taxied clear of the runway, and parked the airplane.

The pilot of the AT-401 reported he had 2 years (and approximately 200 hours) of formation flying experience in T-6 trainers with the Confederate Air Force.

In the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2), under the section titled "Recommendation (How Could This Accident Have Been Prevented," the AT-401 pilot listed "formal formation training and qualification check for all pilots in group. Proper installation of ferry radio equipment."

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.

Collision between aircraft (other than midair)Landing - flare/touchdown
Comm/nav equipment - unreliableFactor
Operation with known deficiencies in equipment - continuedPilot in commandFactor
Clearance - not maintainedPilot in commandCause
Light condition - sunglareFactor
Collision between aircraft (other than midair)Landing - roll
Clearance - not maintainedPilot of other aircraftCause

Aircraft · 2

Registration
N9186J
Reported as
Air Tractor AT-401B
Category
Airplane
Serial number
401 0912
Engine
Pratt & Whitney 1340, 600 horsepower, reciprocating
Damage
No damage
Flight
Personal · Part 91
Registered owner
Southeastern Aerial Corp Service Inc.
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · October 10, 2001 · 20 hours before
Departed
ONY · Olney, TX
Destination
LAS · Las Vegas, NV
Airport
LAS · McCarran International, runway 19R, 9,775 × 150 ft, concrete

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.

Registration
N139LA
Reported as
Air Tractor AT-402A
Category
Airplane
Serial number
402A-1
Airframe hours
9.8
Engine
Pratt & Whitney PTGA-11AG, 550 horsepower, turbo prop
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Air Tractor, Inc.
Airworthiness certificate
Special, Restricted (Special)
Departed
ONY · Olney, TX
Destination
LAS · Las Vegas, NV
Airport
LAS · McCarran International, runway 19R, 9,770 × 150 ft, concrete

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot, aircraft N9186J
Age
49
Injuries
None
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Center
Flight hours
12,000 total · 400 in this make and model
Role
Pilot, aircraft N139LA
Age
39
Injuries
None
Certificates
Airline transport, Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
June 14, 2001
Seat
Center
Flight hours
3,713 total · 20 in this make and model · 3,379 as pilot in command · 30 in the last 90 days · 5 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
80° at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
54 °F, dew point 34 °F
Altimeter
30.01 inHg
Observed at
LAS

FAA reports on this event · 2

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

Other investigations on N9186J · 1

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