Spatial Disorientation, Not Vacuum Pump, Most Likely Cause Of Crash

By ANN Correspondent Juan Jimenez

For some time now I have been following the events of the crash that killed Missouri Gov. Mel Carnahan, his son Randy, and another passenger in their Cessna aircraft on October 16, 2000. It was certainly a sad day; three good people died, and it was a tragedy for their families and loved ones, for the state of Missouri and for the nation.

However, it is clear that what has developed into a legal case is nothing but a blatant attempt by attorneys to get their hands on money they simply do not deserve, based on a sham of an argument.

The NTSB report for this accident clearly shows that a great deal of effort was expended to determine a probable cause. A complete analysis of the conditions of the vacuum pumps, the vacuum system failure indicators and the attitude indicators was performed. Radio contact with the pilot clearly indicated that he was having problems with the primary attitude indicator. The NTSB report states:

"The pilot indicated to ATC several times that he was having problems with the airplane's primary attitude indicator. He also told ATC that he was trying to use the right-side attitude indicator, which indicates that the airplane did not experience a total vacuum system failure. Examination of the wreckage revealed rotational marks in the left and right engine vacuum pumps, which indicates that they were most likely functioning at the time of impact. Further, one of the vacuum gage system failure indicator buttons exhibited evidence of having been in almost the fully retracted position (the other indicator button was found in the partially retracted position), which indicates that adequate vacuum existed for the airplane's instruments to operate."

It doesn't get any clearer than this. The vacuum pumps were most likely working just fine before the crash, so the reason had to lie somewhere else. We're left with two explanations, the ones that the NTSB concluded were the most likely probable causes for the crash:

"The National Transportation Safety Board determines that the probable cause of this accident was the pilot's failure to control the airplane while maneuvering because of spatial disorientation. Contributing to the accident were the failure of the airplane's primary attitude indicator and the adverse weather conditions, including turbulence."

The investigation of the accident included a complete analysis of the left-side attitude indicator, and the determination was made that it was most likely not spinning at full speed at the time of the crash. This was based on a number of observations, not the least of which was the finding that the gyro had scoring marks in the direction of rotation. In addition, the face of the instrument was inverted at the time of the crash, opposite to the attitude of the aircraft when it impacted trees.

Even if one of the vacuum pumps had failed, the system on the Cessna 335 incorporates a check valve into the design that serves to isolate the malfunctioning pump from the rest of the system. Either one of the pumps would have sufficient capacity to drive the entire system - that is why the system was designed to be redundant. A search of the NTSB records and the FAA Service Difficult Report (SDR) database revealed no record of problems with the check valve.

The NTSB analysis of the vacuum indicator revealed that there were no problems with the vacuum failure indicators, and they determined that there was no evidence of a failure indication of either pump at the time of the crash.

The records of radio contact with the aircraft show that he pilot reported that he was using the right-side attitude indicator, which led the NTSB to conclude that indicator was working just fine. Clearly, the vacuum system was working.

The problem with this situation, however, is that in a 335 the right side indicator sits several feet to the right of the pilot. That means that to reference it, he would have had to repeatedly move his head to look at that indicator, then back to reference his own instrument cluster. Combine that with IMC, turbulence and the obvious stress the situation was causing, and add to that the possibility that the pilot was not current for flight in IMC, and you have pretty much all the ingredients for spatial disorientation, not vacuum pump failure.

I hear a bell ringing. Anyone who's read the analysis of another high profile crash involving a politician's son up there where Martha used to grow grapes ought to hear it as well.

We are then left with the task of trying to understand why the Carnahan family is suing Parker-Hannafin, the manufacturers of the vacuum pumps, when there is no evidence that their products contributed in any way to this accident.

For one possible answer to that, we need to go back to the NTSB report to see what other parties might be involved in this issue from a legal standpoint. The attitude indicator/flight director was provided by Sigma-Tek as an overhauled unit in 1996. It had been repaired eleven months prior to the crash and reinstalled on the aircraft. Chances of a good payday from that angle would be nil.

They could have blamed the mechanics who worked on the aircraft in the months prior to the crash, but that has even less of a chance of jackpot award. Besides, there is no evidence that anything the mechanics did had anything to do with the crash - other than the fact that one of them replaced the left engine vacuum pump some two weeks before the crash. The system was tested after that, and it was working properly.

Where do we go from here? Parker-Hannafin, a Cleveland, Ohio company with nearly $6 billion in revenues in 2001, some 46,000 employees as of that year and, of course, deep pockets. Clearly, that was the juicy target, so an argument had to be concocted that the companies products were prone to failure and that over 20 years the company has allegedly known that their products fail.

This "Duh Moment" has been brought to you courtesy of our country's fine tort system, the judges that run it to the benefit of their own, and the politicians who have yet to grow the organs necessary to take on the overdue task of its total overhaul and reform.

FMI: www.ntsb.gov