Viking sold 4 engines this week.  They are identical to the engine sold to the above pictured aircraft. Viking has 15 OEM sales of the Viking 130 and over 120 individual sales to builders across the world.  The 130 engine has been flawless (other than minor updates) since it's introduction 4 years ago.  Several customers and Viking prototype engines have been flying with ECU software much older than the above aircraft.  
This month, the location in Sport Aviation magazine, reserved to brag about builder completions, was hijacked in order to rant about a personal dissatisfaction against Viking Aircraft Engines.  
The events that led to the above off airport landing were:
  • Customer took delivery of the engine
  • Engine + fuel and electrical system was installed by builder
  • Customer complained about the engine not starting / running properly
  • Viking offered to pay for return shipment to troubleshoot.  (If it turned out to be a fault of Viking)
  • The engine arrived and started / ran perfect 
  • Viking continued to inform customer that something was clearly wrong with the installation of either the fuel or electrical system to the engine.
  • Customer believed he knew better and continued to say the issues were caused by him living in Colorado at higher elevation than Florida.  
  • Viking disputed this since the engine ECU compensates for all parameters such as density altitude and temperature.  

  • Viking did a high altitude test to further show that the alleged issues were not related to altitude
  • Customer bought ECU tuning equipment, changed vital parameters such as fuel and ignition timing.  This had already been set through a careful dyno session using sophisticated equipment and skilled personnel.  
Statement from engine tuner:
  • "The engines are all calibrated on an engine dynamometer at steady state. The main fueling map is up to 32 x32 breakpoints of manifold pressure and engine speed. This means that every running point from 800-7000rpm and 200-100mBar MAP can be visited, with a resolution of 250rpm and 50mBar. Each point is held for several minutes against the brake and the air-fuel ratio is set to the optimum value, the ignition timing and variable cam timing are also optimized at the same time. Exhaust gas temperatures are monitored as well as the exhaust gas lambda and detonation using external knock sensing to ensure that the engine is running correctly in every condition. In use, environmental corrections are made for engine and charge temperature and closed loop knock control is used to protect against detonation from varying fuel quality." 

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Were the customer installation errors ever identified so that other customers who are in the installation process (like me) do not make the same mistakes?

It was difficult to get to the root cause since we had a widely different opinion about what the possible causes could be.

Because the customer only wanted to talk about altitude related issues, possibly related to his prior experience with carbureted engines on his Sonex, it was difficult to implement suggestions in regards on how to troubleshoot. A question would be asked and a non-related answer given. Finally we decided to retrieve the engine and test it ourselves. At that point, the customer indicated the engine would start and not continue to run. Once the engine came off the delivery truck, we immediately started it and it ran exactly as it should. Following this we made the high altitude starting test as seen in the video. The engine was returned and the customer immediately reported similar issues as prior to shipping the engine. 

At this point we knew for a fact that there was an issue of some sort with the customers installation. We also knew that it was not altitude related since the engine ECU automatically compensates for this. We found out through our ECU vendor that equipment had been bought and shipped from their shopping cart to Colorado. Once a customer changed the delicate and sophisticated tuning of the engine using a laptop computer it can no longer be considered a Viking engine and our interest in helping quickly dwindled. The tuning of the engine is everything, 30 seconds with the wrong ignition timing can do tremendous damage at 5000 RPM and the same is true about the fuel delivery. It is during this trial and error process we believe the engine was damaged. 

After all this, we finally convinced the customer to return the ECU to have the original software reinstalled. At that point, it was password protected making the customer angry that he no longer had access to "HIS" computer. 

If in fact the engine was damaged at this point the only person that has reported anything about whatever happened has been the customer himself. The NTSB was generated by the customer, any online forum posts were generated by the customer, any possible insurance claims etc. No other person or entity has researched any of the alleged happening. 

Now, back to your original question, Jan loves to review pictures submitted by any customer and usually can find several things that might need slight corrections. We want all of our customers to be as safe as possible and anyone, no matter how skilled would benefit from this service. 

Your doing all the right things by sending in your pictures and documenting along the way. 



At a minimum, EAA editors should allow Viking to present a response in the letters that are comments on each month's content.   I am no longer an EAA member.   Concerned EAA members might consider expressing via email their views on this story, which as Alissa points out in detail, does not tell all the history and is not fair to all parties.


Excellent point. I have been an EAA member for a long time and will voice my concern .


Glenn Davis


I saw Gary's article in sports aviation and rather than a rant, I think he was trying to include his allegations of why his previous engine failed as a side note to avoid being factually challenged. If had been a rant the EAA would have probably challenged it, but since he slipped it in as a side-note, they may have glossed over it.

I am disturbed by the whole situation with Garry's failure, because there has never been an objective postmortem on it engine and he would rather be "right" than allow other builders to learn from the situation. 

As a person who has shipped products to millions of customers, I want to learn the truth about how my product works, even when it is bad news, otherwise I can't make it better.

When we can't get an objective root-cause on failures then the whole community is robbed of the learning.

It sucks that someone has to die for the NTSB to intervene and find out why things broke instead of making a "No NTSB research was actually done on this case" finding.


"When we can't get an objective root-cause on failures then the whole community is robbed of the learning.

It sucks that someone has to die for the NTSB to intervene and find out why things broke instead of making a "No NTSB research was actually done on this case" finding."

You are right on the money there Jonathan.

When I reported the flight control system failure I had in the 650 to the NTSB they and the FAA got all lathered up about it. Once they found out there where no injuries or damage they lost interest.

Glenn Davis


Just to clarify my statement. I am sure Jan was very interested in doing whatever he could to find the root cause of this, or supported a independent investigation had there been access to do so. I don't see the lack on investigation as a lack of interest on Vikings part. The NTSB did not take possession of the wreck and force and investigation, so it was in the owners hands to decide to take part in an investigation or not. It certainly was in Gary's right to not pursue this, but I sure would love to know objectives facts about what led to the failure.

I have not seen any compelling evidence that there is anything for me to objectively worry about, and I guess I am betting my life on it since I will fly my Viking 130 powered cruzer in a few months.  

I agree with Jonathan.

What is the root cause analysis showing as the cause of the engine failure and what is the corrective action to prevent its reoccurrence?

If the builder made an installation error, what is it and how is it corrected?

If there is an engine design/programming problem what is it and how is it corrected.

Any Idea what installation errors were made??

It is very hard to tell.  We put fuel and electric to it when the engine came back and it ran perfectly.  We even made a video of it at the time.  

I too wish we could learn more about the complete story. Truthfully no one has enough information on the cause of the off airport landing to have an informed opinion.


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