
Mags left on accident
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Re: Mags left on accident
Woops, should have been quote from Pelmet, not sure what happened there. 

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Re: Mags left on accident
I personally don't for this exact reason, but I have witnessed 206 pilots push the mixture full rich and throttle full open to avoid having their less than coordinated right seat passenger bend the knobs in getting out of the seat. Perhaps this was the case here?
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Re: Mags left on accident
[quote="PilotDAR"] I don't know why the prop was being pulled through, but it sure seems odd if that was being done with the mixture set rich, but no intent to start the engine. But, odd things happen, I guess....[/quote]
The original TSB statement says "The privately operated Cessna U206F, C-GBPO, was having the prop turned over by hand due to the cold temperature. [u][b]The mags had inadvertently been left on [/b][/u]and the engine started with no one at the controls.
Based on this I assume the intent was not to start the engine. Isn't there an old wives tale about how pulling the prop through when cold loosens the oil.
The original TSB statement says "The privately operated Cessna U206F, C-GBPO, was having the prop turned over by hand due to the cold temperature. [u][b]The mags had inadvertently been left on [/b][/u]and the engine started with no one at the controls.
Based on this I assume the intent was not to start the engine. Isn't there an old wives tale about how pulling the prop through when cold loosens the oil.
Re: Mags left on accident
So again, why on a private plane would the mixture be in if they were not trying to start? I smell fish
Re: Mags left on accident
Mixture in, mags on AND throttle in.Maynard wrote:So again, why on a private plane would the mixture be in if they were not trying to start? I smell fish
Re: Mags left on accident
Maynard wrote:So again, why on a private plane would the mixture be in if they were not trying to start?
Of course we don't know.
One can only guess. The report says the pilot was pulling the prop through in cold weather. Perhaps he tried to start once, had difficulty, got out and accidentally left the mixture rich while pulling the prop through to "loosen oil" or get it to a better position for starting with a weak battery. Or maybe he is lying to investigators about what his intentions were when pulling the prop through which brings us back to the first post of how you should go about it.
These reports are available from the TSB daily reports that you can have emailed to you.
Last edited by pelmet on Tue Oct 22, 2013 5:32 pm, edited 1 time in total.
Re: Mags left on accident
The temperature records are above freezing overnight, but show a couple of degrees below by 10AM. High humidity too.
Battery cranking amps too low on a cooler morning could be the culprit ...
It's good to put a trickle charger on overnite for a few nights in a row at least a few times a year or after parked for a while ... everytime it's low on charge for any reason (best to immediately hook up a small battery charger than leaving it below capacity). Trying to start the engine with a low charge is real hard on those small batteries. Engaging the starter from a completely charged battery-state each time helps keep the available crank-amps at the maximum and extends battery-life.
EDIT: Minimal fibbing here if any. The phrasology: " had inadvertantly been left on" in the Cadors is in the 'second person' (the event described), IMO necessary information for the narrative.
Battery cranking amps too low on a cooler morning could be the culprit ...
It's good to put a trickle charger on overnite for a few nights in a row at least a few times a year or after parked for a while ... everytime it's low on charge for any reason (best to immediately hook up a small battery charger than leaving it below capacity). Trying to start the engine with a low charge is real hard on those small batteries. Engaging the starter from a completely charged battery-state each time helps keep the available crank-amps at the maximum and extends battery-life.
EDIT: Minimal fibbing here if any. The phrasology: " had inadvertantly been left on" in the Cadors is in the 'second person' (the event described), IMO necessary information for the narrative.
Re: Mags left on accident
I have heard that mentioned over the years and can't provode any more detail except what other more experienced persons might say......KISS_MY_TCAS wrote: ↑Fri Oct 18, 2013 9:12 pm Similar to alternator brushes, you can also potentially damage the vacuum pump by forcing the vanes to travel in the direction opposite to normal rotation.
"Some people say you can break a vacuum pump vane by turning the prop backwards, but I’ve never actually seen that in 25 years of maintenance.
Turning the prop backward is a normal procedure during compression testing and during mag timing. It also makes sense to turn the prop backward to put the tow bar on. Adopting this practice just might save a life one day.
Disclaimer: This does not apply to Rotax engines. It does apply to the typical direct-drive Lycomings and Continentals we see on many piston-powered airplanes.”
"Never turn a radial backwards. Doing so can suck oil into the intake manifold leading to possible hydraulic lock and a bent rod when the engine is then turned forward."
https://pilotworkshop.com/tips/turning- ... mpaign=tip
Re: Mags left on accident
It is a subject that is timeless(for our lifetimes anyways) and will be as important 20 years from now as it was 20 years ago. Perhaps you could add some helpful info so that 20 years from now, someone new to the aviation business might avoid serious injury.
I like to provide updates to earlier threads.
Here is a good article with a really interesting video for those interested in the subject....
https://www.flightsafetyaustralia.com/2 ... -the-prop/
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Re: Mags left on accident
God bless Pelmet's noble intentions. It's thanks to him afterall that aircraft aren't crashing as often as they once were!
*Cue Pelmet's inevitable dismissal and or personal attack*

*Cue Pelmet's inevitable dismissal and or personal attack*
Re: Mags left on accident
I always found it strange that the previous poster never added to a thread created to try to save lives/severe injury to a pilot or passenger and would just out of the blue made sarcastic/insulting remarks repeatedly.......and then claim that somehow I am the one making a personal attack. But it does show to newbies the kind of personalities they will encounter in this business.TeePeeCreeper wrote: ↑Fri Aug 14, 2020 5:16 am God bless Pelmet's noble intentions. It's thanks to him afterall that aircraft aren't crashing as often as they once were!![]()
*Cue Pelmet's inevitable dismissal and or personal attack*
I’ll let others decide which they prefer.
Re: Mags left on accident
TeePeeCreeper wrote: ↑Fri Aug 14, 2020 5:16 am God bless Pelmet's noble intentions. It's thanks to him afterall that aircraft aren't crashing as often as they once were!![]()
*Cue Pelmet's inevitable dismissal and or personal attack*



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Re: Mags left on accident
I would have to think that a 206 is not an easy machine to hand prop. The biggest engine I've ever hand propped was an O-320 though.
Re: Mags left on accident
Mine was an IO-360 on twin Cessna. Was actually on a date and fortunately it caught on the second attempt so a positive impression was made which paid off a few hours later.

Re: Mags left on accident
Another interesting comment by someone about turning the prop backwards........pelmet wrote: ↑Wed Aug 12, 2020 11:01 amI have heard that mentioned over the years and can't provode any more detail except what other more experienced persons might say......KISS_MY_TCAS wrote: ↑Fri Oct 18, 2013 9:12 pm Similar to alternator brushes, you can also potentially damage the vacuum pump by forcing the vanes to travel in the direction opposite to normal rotation.
"Some people say you can break a vacuum pump vane by turning the prop backwards, but I’ve never actually seen that in 25 years of maintenance.
Turning the prop backward is a normal procedure during compression testing and during mag timing.
"I have worked on many industrial vacuum pumps of various sizes, both wet and dry and can tell you from some authority and experience that If you turn a prop backwards and break a vane on a vacuum pump then you are doing the owner a favor because that pump is beyond worn out and ready to break anyway. Better to break it on the ground and have that show up on the next run up rather than some random place in the air. As a matter of fact you could consider turning the prop backwards as a mandatory pump safety check."