N7077N

Substantial
Minor

WSK PZL Mielec M-18AS/N: 1Z023-03

Accident Details

Date
Tuesday, August 23, 2005
NTSB Number
LAX05TA277
Location
Elko, NV
Event ID
20051019X01690
Coordinates
41.020000, -115.754997
Aircraft Damage
Substantial
Highest Injury
Minor
Fatalities
0
Serious Injuries
0
Minor Injuries
1
Uninjured
0
Total Aboard
1

Probable Cause and Findings

the pilot's failure to adequately plan for the wind direction and speed during a fire retardant delivery flight, which led to a loss of true airspeed, failure to attain a proper climb rate, and the in-flight collision with mountainous terrain. Contributing factors were the high, gusty, tailwind conditions.

Aircraft Information

Registration
N7077N
Make
WSK PZL
Serial Number
1Z023-03
Year Built
1993
Model / ICAO
Mielec M-18A

Registered Owner (Historical)

Name
SLYS AIRCRAFT SERVICE
Address
PO BOX 754
Status
Deregistered
City
PLATTE
State / Zip Code
SD 57369-0754
Country
United States

Analysis

On August 23, 2005, at 1412 Pacific daylight time, a WSK PZL Mielec M-18A airplane, N7077N (call sign Tanker 426), impacted terrain while maneuvering through a fire retardant drop 12 miles north of Elko, Nevada. The Bureau of Land Management (BLM) was operating the aircraft as a public-use firefighting tool under the provisions of 14 CFR Part 91. The commercial pilot, who was the sole occupant, sustained minor injuries. The airplane was substantially damaged. Visual meteorological conditions prevailed and a company flight plan was filed. The local flight departed the Elko Regional Airport at 1403, and was dropping retardant on the Sherman Fire when the accident occurred.

According to the BLM personnel, the pilot reported dropping a fire retardant load (approximately 500 gallons or 4,035 pounds) downhill in a downwind condition. He dropped the fire retardant at an indicated airspeed between 95 and 100 miles per hour (mph), about 60 feet above the ground, with 30 degrees of flaps extended. After dropping the load, the pilot applied full power, raised flaps to 10 degrees (incrementally), and attempted to climb. According to the pilot, the airplane was incapable of climbing without losing airspeed; however, the engine was producing full power and there were no noted anomalies with the airplane or engine. When the pilot realized he would be unable to clear the ridgeline in front of him, he maintained a wings level attitude and slowed the airplane as much as possible before colliding with terrain.

The airplane impacted the ground at the 7,044-foot level of the 7,090-foot ridge, resulting in the separation of the landing gear, and substantial damage to the wings and flight control surfaces. The pilot was picked up by a ground vehicle and transported to a hospital with minor injuries.

According to the pilot's written statement, the flight was uneventful until reaching the ridgeline near the fire. When the airplane crossed the top of the ridgeline it "encountered turbulence and a down draft." The pilot completed the drop and added power to full throttle and retracted flaps to 10 degrees with an airspeed of 110 mph. The pilot reported that all engine indications were normal and there were no anomalies noted with either the airplane or engine.

The pilot continued to raise the nose to arrest the descent rate and slowed the airplane to 95 mph, but the airplane continued to lose altitude. He then realized the airplane would be unable to clear the next ridgeline and elected to maintain full power while pitching up and slowing the airspeed as much as possible. When the airplane was 20 feet above the ground, the pilot maintained a nose high pitch attitude until the airplane stalled and contacted the ground with little forward speed. He secured the airplane and exited the aircraft.

The pilot reported the wind from the west-southwest at 20 knots with gusts to 40 knots at the time of the accident. At 1456, the Elko Regional Airport's weather observation facility (field elevation of 5,140 feet mean sea level) reported the wind from 260 degrees at 19 knots with gusts to 25 knots. BLM personnel indicated that ground units near the accident site were reporting winds up to 30 knots.

The pilot reported accumulating a total of 13,460 flight hours, of which 550 hours were accrued in the same make and model as the accident airplane.

When asked what could be done to prevent a similar accident from occurring, the pilot suggested the following:

1) Once it is determined that gusty wind conditions exist, tanker pilots should conduct at least one dry pass at a minimum of 100 feet above the ground before making retardant delivery pass.

2) If a lead airplane experiences turbulence or gusty wind conditions they should report the information to dispatch as soon as possible for dissemination to the other air crews.

3) Downwind retardant deliveries over a ridgeline should be avoided in all cases when winds are reported to be over 25 mph.

4) Pilots should never rely on power alone to get out of a downdraft situation.

Data Source

Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# LAX05TA277