This is an excerpt from a report made to the Aviation Safety Reporting System. The narrative is written by the pilot, rather than FAA or NTSB officials. To maintain anonymity, many details, such as aircraft model or airport, are often scrubbed from the reports.
I was on a training flight with a student practicing maneuvers in the practice area when the Cessna 172 began to experience severe engine roughness.
With ZZZ being the closest airport, we made the decision to request priority handling and get clearance to land at ZZZ.
Once we had landed safely and gotten clear of the runway, we exited the aircraft and began to talk with the airport manager about what action to take next.
After talking with the airport manager, she advised me to call my boss (the owner of the flight school and head of maintenance).
While on the phone with him he told me to get in the aircraft and instructed me to run the engine up to full power for a few minutes to burn off any possible spark plug fouling. Afterward, he had me do multiple magneto checks at different RPMs to test if the problem had been fixed. Upon doing the tests, the engine was running smoothly again.
After informing him that the problem had been fixed, my boss, who is also an A&P/IA, advised me to fly the aircraft back to ZZZ1 airport.
From there I discussed with the airport manager and my boss as a group what action to take next. My boss told me that he informed that I was cleared to takeoff to return the aircraft to ZZZ1 airport as long as it was only me aboard the aircraft.
The airport manager discussed with the tower, who also said I was cleared to depart.
At this time my boss made it seem to me like this was the correct thing to do to bring the aircraft back and I felt pressured by my boss and did not want to go against his instructions.
Two days later my chief instructor contacted me about the situation advising me that I had taken the wrong course of action and should have never departed the airport.
After reviewing the regulations I now realize that I did not follow the proper protocol. I learned that as PIC I should not have let anyone influence my decision to fly or not to fly no matter what implications it may have.
Going forward I am going to make a better effort to create a better safety culture and encourage my fellow instructors to never fly no matter how pressured they may feel by external pressures.
Primary Problem: Aircraft
ACN: 2188549
When you click on the link it will take you to the ASRS Online Database. Click on Report Number and put the ACN in the search box, then click Search. On that page, click on “view only the 1 most recent report.”
Wow…so many RED flags in this one:
A pilot’s age isn’t revealed in ASRS reports, but I’m guessing this instrument and multiple-engine CFI is relatively young…and this was his/her first flight instructing job. I’m also going to bet that this CFI is a graduate of that same flight school.
Regardless, the fact that an 800-hour CFI isn’t familiar with the universally recognized ‘technique’ for clearing potentially fouled spark plugs…which obviously they didn’t even attempt in the air…is alarming.
The need to be directed by the airport manager to contact their “boss” for guidance is also interesting: That’s usually standard protocol with any ‘unusual’ incident involving a flight school’s operations. An emergency diversion due to an engine problem certainly qualifies as unusual.
But what is most disturbing …is how he/she got this far into a flying career without understanding the roles, responsibilities and authority that come with being PIC.
This school’s ‘safety culture’, if you could call it that, is in serious need of an overhaul. Having an owner/“boss” and a chief flight instructor so disconnected in their approach to a problem is dangerous for everyone.
I applaud the CFI’s determination to “…. to make a better effort to create a better safety culture and encourage my fellow instructors to never fly no matter how pressured they may feel by external pressures.”
The correct procedure as I was taught by graybeards was to lean aggressively during the run up. If that didn’t work, identify which mag set was rough and get out the wrenches. If you could wait until the engine cooled off you could start the engine on the suspect mag set for 30 seconds and you could often identify the bad plug by feeling for the cooler cylinder.
A severe engine roughness situation is do subjective on whomever is reporting. Sounds like there was plug fouling, which, most likely, could’ve been cleared in flight. Headed towards a divert airport a wise decision in case they couldn’t clear the plugs and it was something else.
Once clearing (burning off) the plugs on the ground and good mag checks why wouldn’t one take off? If the pilot is concerned then don’t take off.
A plug can fowl anytime, thanks to the lead in our fuel. There is a clearing technique many pilots use. and continue on their way.
The aircraft should be written up at home base and go in for maintenance If the instructor was not comfortable he could have said so and the school could send a mechanic to the airport or arrange maintenance …..
Until the FAA approves UL-100 as another approved fuel, fouled or bridged plugs will continue to occur, as well as stuck valves ……
Time to stop flying and instructing, it’s not really a group venue open to what to do next voting 🤔
I would have done what the boss suggested. If it cleared the plugs, maybe take a hop around the pattern to see if it’s good and then proceed home.
So, there is no info if the aircraft engine ran ok on the return flight ?
What was the problem ? Did the instructor try the usual checks.?
a lot of info missing that makes this article worthless.!!
Going forward it might be time for a new boss.