|
|
| ||
|
|
A SumpThis General Aviation Timeline |
|
|
|
1975-1978 |
|
|
Year |
|
Undetermined |
|
|
|
Aviation Safety's May 1983 issue also documents NTSB's further investigation of the procedures published in Owner Advisory SE82-36A. According to the May 1983 issue, the NTSB in February of 1983 arranged with the University of Illinois Institute of Aviation to perform tests. Aviation Safety published the results with indications that the procedures are unreliable noting that "water remained in the [Cessna 182Q's bladder tank]--trapped behind a prominent diagonal ridge on the floor of the cell, as well as in slight ridges and wrinkles elsewhere." |
1983 |
NTSB records indicate that 200 undetermined engine failures occurred in 1983. |
|
| |
1983 |
The NTSB begins to make Safety Recommendations to the FAA regarding the Cessna bladder tank problem. Report No: A-83-6 is a report of NTSB safety recommendations made to the FAA that documents debates between these two agencies over what the solution should be to solve the bladder tank problem. The correspondence contained in the report begins sometime in 1983 and concludes with a NTSB letter to the FAA dated March 25, 1986 that indicates Safety Recommendation A-83-6 has been classified as "Closed--Unacceptable Action." |
|
|||||
|
|
|
|
| |||
|
|
On May 4, 1984, the FAA issued Airworthiness Directive (AD) 84-10-01, a final rule, which was effective May 22, 1984. As issued, the AD was applicable to certain models and series of Cessna airplanes. The AD required inspection and modification of the fuel system. Its prescribed action identified airplanes having bladder fuel cells which tended to retain water contamination, provided fuel tank drainage provisions, and reduced the possibility that water may enter and be retained in the fuel tanks. Eventually, AD 84-10-01 was amended by amendment, 39-5940, that became effective on July 5, 1988. |
1984 |
Here's a side note about the importance of the history to this point and its significance to years that follow. Clearly the NTSB, the FAA and Cessna Aircraft Company were concerned about fuel contaminated with water and made efforts to offer solutions for positive detection of it, but the prescribed solutions were found unreliable in tests indicating that the solutions are unreliable for use in preflight inspections. People tend to trust the FAA and the NTSB on such matters, and rather than question the solutions, most people in general aviation just accept them. Over the years 1983 to 1986, behind the scenes the NTSB properly challenged the solutions, but its challenges were not public enough to get the public's attention. Another importance to years that follow is that metal ridges in Cessna's integral wing tank appear to dam water with the same effect as rubber ridges in Cessna's bladder tank.
|
Tests indicate that metal ridges and rubber ridges dam water. In future years, the FAA, the NSTB and Cessna appear to be less concerned about positive detection. The role each plays in general aviation is made easier if the topic of prevention of fuel contamination replaces the more important safety matter of positive detection. Industry literature seems to deliberately draw attention to prevention. Prevention is important, but detection is far more important.
NTSB records indicate that 166 undetermined engine failures occurred in 1984. |
|
|
|
|
1986 |
Cessna Aircraft Company shut down production of single-engine aircraft. "But in 1986, with just 3,000 employees, they [Cessna Aircraft Company] quit the piston aircraft business altogether. Why? Because of the phenomenal liability costs." |
NTSB records indicate that 165 undetermined engine failures occurred in 1986.
|
|
|
|
|
|
|
|
|
|
|
1975-1978 |
|
|
|
|
|
|
|
|
|
| |||
|
|
|
|
|
|
|
|