LAX99LA240

NTSB accident investigation · Cessna 421B · Polacca, AZ · July 2, 1999

Accident · Minor injuriesLimited investigationFinal report
Date
July 1, 1999, 18:50 local (Jul 2, 1999, 01:50 UTC)
Place
Polacca, AZ
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N5943MCessna 421B
Weather
Visual (VMC) · Dusk
Status
Completed · report April 6, 2001
Report
Approved by Office Director
FAA report
19990701008009A
Case key
46727

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 pilot's inadequate preflight inspection, which failed to determine the fuel supply in each fuel tank, and his mismanagement of the fuel supply, which resulted in fuel starvation.

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(total) - nonmechanicalTakeoff - initial climb
1 engineCause
Fluid,fuel - starvationCause
Aircraft preflight - inadequatePilot in commandCause
Fuel supply - not verifiedPilot in commandCause
Loss of engine power(total) - nonmechanicalManeuvering - turn to landing area (emergency)
Fluid,fuel - starvation
2 engines
Aircraft preflight - inadequatePilot in command
Fuel supply - not verifiedPilot in commandFactor
Induction air ducting - disconnected
Maintenance,installation - improperCompany maintenance personnel
Forced landingEmergency descent/landing
Terrain condition - none suitable
In flight collision with objectDescent - emergency
Object - tree(s)

Analysis

During the initial climb after takeoff, both engines lost power and the pilot force landed in the desert. The airplane was on a positioning flight following a right engine change because of a previous engine failure, which had occurred about 1 month prior to the accident. The airplane had remained parked on the ramp at the airport without security. The operator said that they usually provided security for airplanes parked in remote locations due to past incidents of vandalism and fuel theft, but did not do so on this occasion. The pilot of the accident airplane did not visually check the fuel quantity; instead, he relied on the fuel gauges. He did not open the cowling on either engine but relied on the mechanic's word that the aircraft was ready for flight. After takeoff, when he changed the left fuel selector from the main to the auxiliary tank, the engine quit. He turned toward the runway, switched the fuel selector back to the main tank, and turned the left fuel boost pump switch to high. The left engine fuel flow was near zero and there was no effect with the boost pump. He then noticed that the right engine was losing power. He did not feather either propeller. When he determined he would not reach the runway, he stalled the airplane into bushes to cushion the landing. Postaccident examination revealed that there was no fuel found in either the left or right main tip tanks. The left tip main tank was broken open during the forced landing with no evidence of fuel spray on the surrounding vegetation. Aircraft recovery personnel found 18 gallons of fuel in the left auxiliary tank and 23 gallons of fuel in the right auxiliary fuel tank. The right engine air induction tube was disconnected at the inlet flange to the fuel/air metering control unit. Fuel consumption calculations on the preceding flights and ground runs failed to account for approximately 74 gallons of fuel. Both engines operated to manufacturer's specifications during postaccident examinations in test cells. Fuel analysis of samples from the various tanks contained high particulate contamination consisting of rust, dirt, iron, and flakes of aluminum.

Factual narrative

History of flight

On July 1, 1999, at 1850 hours mountain standard time, a Cessna 421B, N5943M, collided with the ground during an emergency descent near Polacca, Arizona. According to the pilot, he experienced a loss of power in both engines during the initial climb after takeoff. The commercial pilot received minor injuries. The airplane was substantially damaged. The airplane was owned and operated by Scenic Aviation of Blanding, Utah, and was on a positioning flight under 14 CFR Part 91 when the accident occurred. Visual meteorological conditions prevailed and a flight plan had not been filed. During the flight, the pilot planned to obtain company flight following. The flight was originating at the time of the accident.

According to the operator, on June 2, about 1 month prior to the accident, the right engine failed and the pilot had landed at Polacca. The airplane remained parked on the ramp while a new engine was obtained. According to the pilot, the engine had failed because of a mechanical malfunction of the accessory-drive gear. In the days preceding the accident, company mechanics changed the right engine.

On the afternoon of July 1, 1999, the pilot said the company dispatcher notified him that the airplane was ready for flight. In a telephone interview, the pilot told the Safety Board investigator that he did a preflight inspection of the airplane prior to departure. He stated he did not "stick" the fuel tanks, nor did he visually check to verify the fuel quantity. The pilot said he sampled fuel from both the main tanks and the aux tanks. He also said he did not open the cowling on either engine, but took the mechanic's word for it that the airplane was ready for flight.

The pilot reported that the fuel gauges onboard the airplane read as follows:

Left main tank: 15 gallons Left auxiliary tank: 25 gallons Right main tank: 25-30 gallons Right auxiliary tank: 15 gallons

The pilot stated that he did one run-up in the parking area of the airport and that everything appeared to be within limits. He stated that the engine start and warm-up was normal. He stated that he performed a standard run-up while he was on the tarmac area. He said that he taxied down to the end of the runway and performed another partial run-up, this time he again checked the magnetos and propellers. He estimated that 6-10 minutes had elapsed during the startup to completion of the second engine run-up.

He said he was climbing out and had reached 800-1,000 feet above ground level (agl) and was setting climb power when he changed the left fuel selector from the main to auxiliary tank. The engine lost power and quit. He then switched back to the main tank on the left engine and turned the left fuel boost pump switch to "high." He stated that there was no effect and after about 10 seconds, he returned the pump to low. He stated that the left engine fuel flow was down "near zero" and he put the left boost pump on high with no change in fuel flow.

As the pilot was going through the abnormal procedures checklist for engine failure, he said he noticed that the right engine was also losing power. He noticed that the right manifold pressure was only 23-24 inches and decreasing. The pilot stated he never changed the right engine fuel selector position during the power loss. He said he verified that he had mixture, props, and throttles full forward, and noticed that the left manifold pressure gauge was reading "about 15 inches of pressure, and the right manifold pressure gauge was reading less than 25 inches."

The pilot said he did not feather either propeller as he attempted to make it back to the airport because he was hoping that he could regain some engine power. He maneuvered to land on some bushes when it became apparent to him that he was not going to make the runway. He said he was getting a "stall/buffet" as he landed off airport. The pilot stated that he realized that he was not going to be able to make it back to the airport, so he deliberately selected a clump of Tamarisk bushes to cushion his landing.

Airplane recovery

Recovery personnel arrived on scene the following day. They reported that the left main tip tank was ripped in half and there was no evidence of any fuel spray on nearby shrubs. No fuel found in the left main tank. Approximately 18 gallons of fuel was removed from the left auxiliary tank.

Eight ounces of fuel was in the intact right main tank. According to the recovery personnel, the right auxiliary tank was undamaged and they off-loaded approximately 23 gallons of fuel. The right engine air induction tube was found disconnected at the inlet flange to the fuel/air metering control unit. The clamp, which held the air hose on, was tight. Both fuel selector handles were in their respective main tank selections.

Personnel information

Review of Federal Aviation Administration (FAA) Airman Records disclosed that the pilot held a commercial pilot certificate, with airplane ratings for single engine land, multiengine land, and instruments. His most recent second-class medical certificate was issued on May 26, 1999, without limitations.

According to all sources of information, the pilot had accrued a total flight time of about 8,800 hours, with 2,400 hours in multiengine aircraft, and 1,200 hours in the Cessna 421B.

The company had employed the pilot for approximately 6 months. His most recent flight checks, in accordance with the provisions of 14 CFR Part 135, were completed in May 11, 1999, in a Cessna 421. Additionally, the pilot was recommended by the chief pilot as a company instructor in the Cessna 421B and C model after a company check ride was completed on May 12, 1999.

Maintenance history

A review of the aircraft maintenance logbook revealed that on July 1, 1999, company mechanics installed a Western Skyways remanufactured engine GTSIO-520-H, S/N 128347, in the right-hand position. The log noted that they had replaced the engine mount bushings with new ones; installed all new fuel and oil hoses; and installed an overhauled propeller governor. All operational checks were found "normal" as noted in the logbook. An Airframe and Powerplant mechanic, who is also an IA who did work on the airplane prior to calling for the pilot, said that they worked on only the right engine. All the engine runs were completed on the day of the accident. He said that the mechanics performed five ground-run's totaling approximately 13 minutes. Additionally, he said that they performed a full power ground run for about 7-8 minutes. He stated that the fuel selectors were all on the main tanks during the engine runs. The mechanics checked the fuel quantity on the auxiliary tanks by looking at the gauges, and then returned the fuel selector to the main tanks. They did not do a specific preflight inspection of the airplane. They did do a thorough inspection on the right engine. He stated that they did not "stick" or visually check the fuel, and did not pop the cowling on the engines.

Another pilot, who works for the company, submitted a statement concerning the amount of fuel onboard the airplane before the accident. He stated that on June 2, 1999, after completion of an air ambulance flight from Chinle to Tucson, Arizona, he wanted to verify the fuel gauges were reading correctly in the airplane. He said he noted the gauge readings on the main (tip) and auxiliary tanks, and confirmed the readings as the line crewman topped each tank. He said he determined that both the main and auxiliary fuel gauges were reading correctly, (within 1-2 gallons). He said he did not check the nacelle tanks.

The pilot provided fuel consumption calculations estimating there was about 70 gallons of useable fuel at the time of the accident departure. A total of 41 gallons of fuel was found in the auxiliary fuel tanks during the recovery of the airplane wreckage.

Component examin

Aircraft

Registration
N5943M
Reported as
Cessna 421B
Category
Airplane
Serial number
0316
Airframe hours
4,056
Engine
Continental GTSIO 520, 375 horsepower, reciprocating
Damage
Substantial damage
Flight
Positioning · Part 91
Registered owner
Scenic Aviation Inc.
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · July 1, 1999 · 12 hours before
Destination
BDG · Blanding, UT
Airport
4PH · Polacca Airstrip

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
53
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Left
Flight hours
8,800 total · 1,200 in this make and model · 8,500 as pilot in command · 130 in the last 90 days · 30 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Dusk
Wind
240° at 16 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
93 °F, dew point 39 °F
Altimeter
29.00 inHg
Observed at
KFL

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 N5943M · 1

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