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Meet  Robert E. Scovill, Jr. _______________________________

Education: BS Psychology with a Minor in Aviation; Masters in Psychology.
Aviation: Commercial pilot, airplane single and multiengine land instrument airplane. AOPA Member (00787333) since 1982. Owner of a 1981 Cessna 172P Skyhawk II.
Occupation: Entrepreneurial endeavors in real estate, and rental properties. Licensed General Contractor.

Hi, I'm Robert E. Scovill Jr, shown above in a photo in the mid 80's, flying my 1981 Cessna 172P. This photo illustrates my love of aviation, as if to say "Man this is fun! I love it!" Most of my 34-years in aviation has been recreational, although safety has always been an overriding concern.

After years of enjoying aviation, on August 24, 1997, during a flight in my Cessna 172P, I experienced a rough running engine that I eventually came to realize was a consequence of fuel contaminated with water. Following this event, during three other flights, I experienced total engine failure. I now know that the underlying cause of the engine failures was fuel contaminated with water, and I also know that this cause can occur because of a problem with the design of Cessna's integral wing tank.

My objective is to alert others to the problem and perhaps provide an opportunity for someone to offer a solution that will address the design flaw. Additionally, I would like to raise awareness over the FAA's apparent inability to respond quickly, alerting the public to findings that involve life-threatening situations although they are obligated to do so under existing regulations. Finally, I would like to address the current classification and reporting of aircraft accidents, by the National Transportation Safety Board. My review of the NTSB aircraft accident reports indicates a need for a careful public review of the current system, which may allow serious problems to go undetected.





















 A New Attitude Unveiled

Below is an image of me taken during an inspection while performing a test on one of Cessna's integral wing tanks.

In the image, I am holding cups that are used to sample fuel during a preflight check. The cups are shown containing water with red food color added. To perform the test, hazardous quantities of water, such as that shown in the image, were added to integral wing tanks containing fuel. Then samples of fuel were taken from sump drains to determine if the water that was added could be detected. As shown in the image below, none of the colored water could be collected in the cups"

The procedures for performing the tests and the results of them are in the documentation section of this web site.

If water is in the fuel tank, regardless of how it got there, a pilot must be able to detect it. Both CARS and FARS require a means of detection for FAA certified aircraft. For years, Cessna has been manufacturing their integral wing tank with FAA certification, but my tests show that the wing's drainage system can permit water to go undetected. Furthermore, the drainage system does not drain all hazardous quantities of water, which is also a certification requirement.

Over the years, thousands of pilots have sampled fuel from sump drains on Cessna integral wing tanks as part of their preflight checks. I now know that this precautionary safety measure may have been misleading on many occasions to many pilots because when water is present as a fuel contaminant in a Cessna integral wing tank, it is possible that the water will not flow to a sump drain.

How effective is certification testing?

Cessna profits from FAA certification; people buy FAA certified aircraft because of the FAA's airworthiness standards. FAA regulations for type design require tests to be performed and data from those tests to be recorded that demonstrate proper functioning of an aircraft's fuel drainage system. With regard to these regulations, Steve Brooks, Manager, Technical Information Services of Cessna Aircraft Company, in his letter dated October 4, 1999 says, "Certification testing of the integral fuel tank has demonstrated the original fuel drain (1 each per wing) to sufficiently allow detection of contaminants with the airplane at a level normal ground attitude."

Some aircraft equipped with Cessna's integral wing tank are listed in Type Certificate Data Sheet No. 3A12 where production basis shows that the FAA issued Cessna Aircraft Company a production certificate and a delegation option to manufacture the aircraft in question. Given these certifications, it is difficult to understand how a Company like Cessna and a government agency like the FAA could both overlook a flaw in the drainage system of aircraft manufactured with the integral wing tank.

What of NTSB accident reports?

In order to demonstrate how the flaw may have gone unnoticed on aircraft that are in service, I need to state some observations that I have made about NTSB reports. First, NTSB reports cannot be used as evidence in court, which means that plaintiffs in product liability cases would have less reason to rely on or give extensive review to facts available in NTSB reports. Also, NTSB does not report conclusive findings. They only report probable cause. (Note: the purpose of my efforts is not to use my circumstance to file a product liability case. On the contrary, I am trying to prevent such a case from occurring. Such a case will require one to be injured, killed or property damaged before it can become a product liability case. That is how our system works. And it makes what I am trying to do difficult.)

Others and I have been studying NTSB reports. There is an important observation that we have all made that does not seem to be statistically reasonable. Our study of NTSB accident reports indicates that for general aviation aircraft accidents, a lack of sufficient numbers of probable cause due to design flaw is statistically significant. That is, general aviation accidents are too likely to be the fault of people using aircraft technology; rarely is the manufacturer of the aircraft technology the blame. We doubt that the technology is really that good, but more research is needed to reveal if hidden facts support our doubts. Cessna's integral wing tank design is about twenty years old, and it is easy to understand why the flaw has gone undetected for 20 years: The NTSB, aircraft owners and pilots for twenty years have assumed that the drain system works properly. When this assumption is removed, NTSB reports actually encourage testing to see if Cessna's integral wing tank drainage system is flawed.

For example, NTSB uses a probable cause phrase similar to Weather conditions conducive to carburetor ice. This probable cause is often used when no evidence of what caused an engine failure can be found. It implies that ice formed on the carburetor, but melted before being witnessed as evidence. In a case where water is found in the fuel tanks, a probable cause may state a phrase similar to Pilot performed insufficient preflight check.

In accidents where an engine failure is known to occur, but no evidence remains after a crash to determine the cause of an engine failure, it appears that NTSB may report that probable cause was Weather conditions conducive to carburetor ice. If an aircraft involved in an accident occurring from engine failure is equipped with Cessna's integral wing tank, evidence of water can be lost either because the wings are destroyed, or their contents are drained from holes caused by damage from a crash. NTSB may determine that an engine failed, but they may have no evidence to explain why it failed, so a report could be filed with probable cause stating Weather conditions conducive to carburetor ice, but the real cause could have been something else.

If water is present in the fuel tank after an accident, NTSB could possibly report that the probable cause is Pilot performed insufficient preflight check. But if a pilot involved in such an accident performed his preflight check on a Cessna integral wing tank, there is a good chance that he could not have detected water contamination in a perfectly sufficient preflight check. This circumstance is not the pilot's fault. It's the manufacturer's fault, but the pilot gets blamed, and the manufacturer continues to sell the design flaw with FAA certification.

The above examples of incorrect probable cause hint at the danger of assuming that the integral wing tank's drainage system functions properly.

I am not trying to show that the NTSB is deliberately making false reports. I am, however, suggesting that a public review of these reports is needed to determine if NTSB is overlooking (unintentionally) manufacturer design flaws in general aviation aircraft. NTSB's primary mission is to investigate major airline crashes. General aviation accidents involving small aircraft receive secondary attention from NTSB, yet the bulk of air operations and accidents occur in general aviation aircraft.

To substantiate my observations made in the NTSB reports, I need only refer to one of my engine failure experiences. I had an in-flight engine failure that resulted in my landing in a field. The history of this event may be read in my letter to the FAA dated April 19, 1999. It's available in the document section of this web site. Interested readers should refer to the August 28, 1998 history in the letter, and hypothetically consider how the NTSB's final report would have reported probable cause if I had crashed, not survived and the wings were damaged in a way to permit their contents to drain. Using this hypothetical scenario add to it that without evidence of water at the scene of the accident, if the NTSB questioned the mechanic who witnessed me sampling the fuel in my preflight check, they would have learned that there was no water detected. This hypothetical situation would have no doubt been written with probable cause stated as Weather conditions conducive to carburetor ice, when in fact, the cause was water that was not detected during the preflight check because of a manufacturer's design flaw.

I survived one rough running engine and three engine failures. After reviewing NTSB reports, I can clearly see that I am lucky to have survived any one of them. And if I had not survived, I would not be here to speculate NTSB's probable causes unintentionally hiding manufacturer design flaws by assuming that Cessna's integral wing tank drainage system functions as certified. It is as if there is too much confidence placed in the certification process. A confidence that dangerously assumes that if certified, it can't be wrong.

There appears to be a need to add some additional probable cause phrases to NTSB's canned phrases. Here is an example that stresses my point: Probable cause: Manufacturer performed insufficient type design test.

It is clear that NTSB reports can easily direct attention to the wrong probable cause, and that is how Cessna's integral wing tank design flaw may have been overlooked for almost twenty years. To err is human. Humans fly aircraft. Humans manufacture aircraft. Humans investigate aircraft accidents: Another phrase needed for Probable Cause is Conditions conducive to NTSB err.

Public Action Needed

Public action is needed that seeks remedies to the problems that I have identified. Solutions need to be found and presented to Congress and the Department of Transportation. Any volunteers? I want aviation to be fun. But more importantly, I want it to be safe. I am concerned. The FAA is concerned. The NTSB is concerned. Cessna Aircraft Company should be concerned. Are you?

Thank you for visiting Sump This. Please help spread the news. Read the documents and view the images. If you are someone who would like to volunteer to help on the issues that I've presented, send me an email stating your interest.

Robert E. Scovill, Jr.


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