A Recommended Method for Examining Aircraft Accidents Listed in this Petition: Examination of NTSB's CHI92FA020 Report

 The following examination of NTSB's CHI92FA020 report is an example of how the petitioner recommends that the NTSB review reports contained in his petition. The method of examination deliberately seeks clues for potential factors and potential causes that the NTSB either did not investigate or appears to have inadequately investigated. Specifically, within the context of the petition, clues to look for include opportunities for the NTSB to recognize as potential factors or potential causes an aircraft's fuel system design and preflight procedures for it. If NTSB had opportunity during an investigation to recognize these potentials, but either overlooked them, or did not adequately investigate them, then the relevant aircraft accident report should be reconsidered in light of the new evidence given in the petition. The petitioner's examination of NTSB's CHI92FA020 report should make his recommended review process clear.

In addition to using information from the NTSB's final report for CHI92FA020, this examination also uses information that is recorded in the attached factual reports and record of interviews. These latter documents are attached immediately following the pages of this examination.

The aircraft accident identified by NTSB Identification CHI92FA020 occurred Thursday, October 31, 1991 at ZION, IL. According to an attached record of interview with the pilot in command, the aircraft involved was a Cessna 172P equipped with Cessna's integral wing tanks. The aircraft's registration number recorded in NTSB's accident report is N5411K. The report also indicates that there was one serious injury resulting from the accident. The NTSB event number for this accident is 20001212X18260. According to NTSB's record, its final report was approved on Tuesday, December 15, 1992, which is more than thirteen months after the date of the accident.

NTSB's probable cause narrative for CHI92FA020 reads as follows.

"WATER CONTAMINATION OF THE FUEL, AND THE PILOT'S INADEQUATE PREFLIGHT OF THE AIRCRAFT. FACTORS RELATED TO THE ACCIDENT WERE: DARKNESS AND OBSTRUCTIONS (TREES & TRANSMISSION LINES) IN THE EMERGENCY LANDING AREA."

The petitioner's following remarks will focus on the above narrative's first line, "Water contamination of the fuel, and the pilot's inadequate preflight of the aircraft," which is a restatement of the sequence of events in the report's first occurrence, LOSS OF ENGINE POWER, recorded by the NTSB.

Occurrence: 1, LOSS OF ENGINE POWER

Phase of Operation: CLIMB - TO CRUISE

Sequence of Events for Occurrence Number: 1

1 ( Cause ) FLUID, FUEL / CONTAMINATION / (0)

2 ( Cause ) FLUID, FUEL / WATER / (0)

3 ( Cause ) AIRCRAFT PREFLIGHT / INADEQUATE / PILOT IN COMMAND

The NTSB's final narrative contains two clues that indicate an opportunity to recognize that the aircraft's fuel system and preflight procedures for it are potential factors or potential causes. The following two statements are the clues taken from the final narrative.

Clues

1.

"AN ON-SCENE INVESTIGATION REVEALED WATER IN THE CARBURETOR FLOAT AND ACCELERATOR PUMP CHAMBERS."

2.

"DURING AN INTERVIEW WITH THE PILOT, HE STATED THAT HE HAD TAKEN A FUEL SAMPLE FROM EACH FUEL SUMP ON THE AIRPLANE DURING HIS PRE-FLIGHT WALK AROUND INSPECTION."

The first statement is a clue for a potential factor or potential cause that directs attention to the fuel system. The second statement is a clue for a potential factor or potential cause that directs attention to preflight procedures. Clearly, these two statements show that the NTSB during its investigation was aware of these clues. Therefore, the method of examination for this report seeks to determine if an adequate investigation of these clues was performed.

The following excerpt is the second paragraph of the History of Flight taken from the attached factual report dated January 13, 1992.

During an interview with the pilot he stated he had taken a fuel sample from each fuel sump on the airplane while performing the pre-flight inspection. He stated that he did not notice any water in each of the three samples taken. According to the pilot, N5411K had sat outdoors during an eight-day period of almost continuous rain.

The following excerpt from the record of interview dated November 12, 1991 with the pilot in command, PIC, of N5411K provides more details about the comments made in paragraph two of the above factual report.

The PIC was asked to describe the pre-flight inspection he performed. According to [him], the preflight inspection was typical and did not reveal anything unusual. He described the inspection in detail. He stated that N5411K had been sitting outside during an eight-day period of almost continuous rain. [He] indicated that he was particularly careful when he checked his fuel because of this.

When asked how he examined the fuel in the wing tanks and fuel gascolator he stated that he took a sample of fuel using the cup provided (a small fuel sampler made of clear plastic which holds approximately 2-3 ounces of fuel and has a small metal shaft protruding upward from the sampler's internal center). He stated that he looked at the fuel using his flashlight and observed it to be blue in color. He stated that he did not observe any water in the fuel samples drawn.

The PIC was asked if he took more than one sample of fuel from each of the fuel sumps. He stated that he did not. He stated that he made sure that one of the fuel caps was the "vented" type during his pre-flight inspection of N5411K.

Other parts of the factual report indicate that the NTSB reviewed the aircraft's logbook, surveyed the wreckage, inspected the carburetor, vacuum pump and gyro-powered instruments. There is no indication that the NTSB investigated the fuel tank design or the aircraft's published preflight procedures, both of which are directly related to the causes listed by the NTSB in the first occurrence of the final report, loss of engine power.

Occurrence: 1, LOSS OF ENGINE POWER

Phase of Operation: CLIMB - TO CRUISE

Sequence of Events for Occurrence Number: 1

1

( Cause ) FLUID, FUEL / CONTAMINATION / (0)

2

( Cause ) FLUID, FUEL / WATER / (0)

3

( Cause ) AIRCRAFT PREFLIGHT / INADEQUATE / PILOT IN COMMAND

The final report does not substantiate NTSB's findings for the cause of the third event. There is no documentation in the report that reveals how or with what evidence the NTSB used to arrive at its conclusion that the PIC's aircraft preflight was inadequate. It appears that the NTSB is simply saying that water was found in the carburetor float and accelerator pump chamber, so an additional cause for engine failure is that the PIC performed an inadequate preflight check. It seems practical to expect that with more than thirteen months spent on this investigation that the NTSB could have provided some information that substantiates its findings. This lack of substantiation is a clue that the NTSB performed an inadequate investigation for the third event of occurrence one.

For example, further above, it was pointed out that clue one directs attention to the fuel system. The NTSB investigated the carburetor and accelerator pump. It also noted in the factual report that "An on-scene investigation of the N5411K's fuel tanks revealed both were structurally compromised and devoid of fuel." There is no indication that the NTSB investigated the fuel tanks from a preflight perspective. Yet fuel tank design and its sump drains are relevant factors in the PIC's preflight check. The NTSB does not explain how the PIC's preflight check is inadequate with regard to the fuel system. Oddly, an aircraft system component, the fuel tank, that is a significant factor in the PIC's preflight check is given little attention in the investigation. Compare the attention given to other components that are discussed in the factual report. For example, the gyro-powered instruments are given a great deal of attention. The new evidence contained in the petition indicates that the NTSB should include fuel system design among its list of system components to be adequately investigated.

Further above, the second clue given in the report's final narrative directs attention to preflight procedures. Specifically, the cause of the third event states without narrative substantiation that the aircraft preflight was inadequately performed. A question is raised here. What preflight procedure or procedures were performed inadequately? Safety in general aviation demands an answer to this question. The final narrative, the factual report and the record of interview with the PIC clearly establish that the PIC took fuel samples during his preflight check. Is the PIC's fuel sampling the procedure that was performed inadequately? If so, how was it performed inadequately? If not, what procedure was performed inadequately that makes it relevant to the causes of occurrence one, loss of engine power? The petitioner believes that the NTSB means to imply that the PIC performed and inadequate fuel sampling procedure, but lack of substantiation on this matter makes it impossible to know for sure.

For the NTSB to find the aircraft preflight inadequate based on fuel sampling procedures, it must disregard the PIC's statements that discuss his aircraft preflight, which is exactly what the NTSB did. Otherwise, if the PIC's statements are not disregarded, the NTSB must investigate to determine an answer to the question, "Why did the PIC, who took a fuel sample during his aircraft preflight, not detect water"? An investigation into this matter would have lead investigators to inspect the fuel system design and the aircraft preflight procedures for it, but the NTSB did not investigate this matter. Thus, the investigation was inadequate.

During an aircraft preflight, a pilot uses published preflight procedures to interact with the fuel system to take fuel samples for the purpose of detecting fuel contamination. Examination of the CHI92FA020 aircraft accident report reveals that the NTSB investigated the PIC, but chose to ignore what it learned from him. Additionally, the NTSB completely ignored the fuel system and its preflight procedures from an aircraft preflight perspective. These factors, like the PIC, must function adequately to detect fuel contamination. If the PIC performed an inadequate aircraft preflight, the NTSB must show that the fuel system and preflight procedures for it are adequate. In this investigation, the NTSB failed to show the latter, so its ruling of the third event for occurrence one should be reconsidered.

The petitioner recommends that the NTSB use the examination method just demonstrated or similar methods to examine the aircraft accidents listed in his petition.