The initial investigation was conducted by local law enforcement in conjunction with the FAA. Now the National Transportation Safety Board will take over.

The NTSB’s job will be to examine the wreckage and attempt to determine if the crash was caused by a defective aircraft part, negligent maintenance, or pilot error. The NTSB concedes, however, that it lacks the manpower, the technical expertise, and the funding to do that job properly on its own. Therefore, as a matter of long-standing policy, it will seek engineering assistance from the companies that manufactured the aircraft components in question. In this case, the NTSB will recruit the help of Cessna Aircraft, which manufactured the aircraft involved in the accident, Cessna N5225J, and Teledyne Continental Motors, which manufactured each of the aircraft’s two 260 horsepower C-310 File Photo by Kensavition.comengines. The NTSB will exclude members of the victims’ families and their technical representatives from the investigation, feeling that they have nothing to offer. (Sad but true.)

Of course, the NTSB’s practice of asking the manufacturers for help – a practice it calls “the party system” — presents a conflict of interest.  After all, the manufacturers themselves might be the ones responsible for the accident. Some say that the NTSB’s party system is akin to asking the suspects for help in solving a crime. Nonetheless, the conflict – discussed further here – is ingrained in all NTSB investigations.

It’s no surprise that most NTSB final reports often favor the manufacturers who have “assisted” the NTSB investigators in their work. But perhaps it doesn’t make any difference because, by federal regulation, the NTSB’s probable cause findings are not binding on anyone. The families are free to conduct their own investigation, and in the event of a lawsuit, the NTSB’s conclusions are given no deference whatever. In fact, in the event of litigation, the NTSB conclusions are not even admissible. Aviation attorneys who conduct their own independent investigations find that the NTSB’s conclusions are wrong about 50% of the time.

In one recent example, a Teledyne Continental engine similar to those installed on N5225J quit

and the plane crashed. The NTSB asked Teledyne Continental Motors to participate in its investigation and help it determine why the engine failed. Not surprisingly, after hearing only Teledyne’s side of the story, the NTSB determined that the engine failed because of poor maintenance, and not because of anything that Teledyne did. In fact, the NTSB cleared Teledyne completely of any blame. After hearing all the evidence in the case — not just the evidence favorable to Teledyne — the jury disagreed, determining that it was an error in Teledyne’s maintenance manuals that caused the failure.Teledyne Engine Being Disassembled After Failure

Though it takes the NTSB from 18 months to 4 years or more to release its report of an accident’s probable cause, the NTSB is typically finished with the wreckage in just a few months. At that point, the NTSB will release the wreckage to whoever owns it. The owner – usually an insurance company at that point – is then free to sell, salvage, or destroy the wreck, unless the families or their attorneys have interceded. More on that here

Some basic things that should be looked into when examining 5225J’s wreckage:

Flight Control (steering) system:

  • Is there system continuity? In other words, do all the cables leading from theAttitude Indicator control yoke connect where they are supposed to connect?
  • Are the controls “correct”? Or were they inadvertently reversed around a pulley during maintenance, causing the aircraft to turn in a direction opposite to the pilot’s inputs? (Not uncommon; example here.) 

Instruments (used for keeping the plane straight and level in fog or clouds):

  • Disassemble the Attitude Indicator (‘artificial horizon") and Heading Indicator (similar to a compass) to determine whether either failed in flight.
  • Disassemble the vacuum pumps used to power the gyroscopic instrumentsHeading Indicator to determine whether one or both failed before impact.


  • Look for rotational damage on spinner, propellers and associated surfaces that would indicate that engines were turning on impact.
  • If crankshaft can be turned by pulling on the propeller, determine whether engine will operate on a test stand. If so, look for  evidence that the engine, as installed in aircraft, had been deprived of the fuel, air, or electrical spark needed to support combusion.
  • If crankshaft cannot be turned, disassemble engine to identify the internal damage that prevents rotation.  Determine if damage was the result of impact forces (for example, bent crankshaft) or rather, instead, whether the damage was the cause of the engineInside of Vaccum Pump failure (for example, failed piston).
  • Send questionable parts to appropriate laboratories to assist in failure analysis. 

The NTSB investigator will not necessarily take all of even these basic steps if he or she feels that they are not necessary. For example, in the case involving the failure of the Teledyne Continental engine mentioned above, the NTSB didn’t even bother to disassemble the engine, apparently relying on Teledyne’s view that it wouldn’t be productive. 

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