No one understands these things.

How do Magnetos work?  If you are asking what a magneto is, you’re probably in the wrong Club.  Most of the time, it would be better just to say magic and fairy dust than the answers I’ve heard.  I would imagine all of you understand what a Magneto is.  But do you really understand what a magneto is?  And of course the follow-up question is, why should you care.  

Clear, Prop!
In this day and age, we take starting engines for granted.  In one of my Jeeps, I press a button and magically, it starts.  Airplane engines are waaaay behind the times.  Our vehicles are so far advanced that most of our airplanes have a kind of machine envy.  This is especially true for the airplanes that sit by the fence just tormented by all those pretty cars right outside the fence.  When we get in our trusty airplane to “slip the surly bonds of earth” we don’t think twice about what goes into keeping your engine running.  Hello Magneto.  Many of you are probably familiar with an alternator.  After all, you have one in your car, unless of course you have one of those electrical contraptions.  The alternator provides your engine with the sparks it needs to generate the combustion which is, of course, required for your combustion engine.  What happens though, when that alternator decides it is taking the day off?  No spark = No combustion = Hello, AAA?

The magnetos help with this problem by ensuring that as long as the engine is actually turning, the magnetos are also turning and, in a healthy magneto, creating a sufficient spark required for combustion.  When your engine fires up, the permanent magnet (hence the term magneto) inside the magneto rotates around a high output electrical coil, which then sends a spark to the spark plugs.  Each magneto is wired to a spark plug in each cylinder of your engine.  This is a slight oversimplification to the inner workings of the magneto but it gives you the basic concept.  The magneto is basically an alternator.  It generates alternating current as the poles of the magnet rotate around the coil.  

Impulse Coupling
The vast majority of pilots rarely take the time to really understand that big metal box they trust their’s and their families lives to.  

When you move the prop, say to push the plane back into its spot, sometimes you hear a “click” from inside the engine compartment.  Have you ever wondered what that was?  If you were to get in your car, start it up, and heard the cry of a chupacabra, would you be at all curious as to what may be in your engine compartment?  Of course you would.  

The impulse coupling is a clever little device really.  Its main job is to “charge” up the magnetos to be able to provide just a bit more energy during the start sequence.  Think of it this way.  Magnetos have been around for a LOOOONG time.  The theory of electromagnetic induction was discovered in 1831.  By 1914, magnetos were all the rage on Facebook and Twitter.  That’s 104 years of pretty-much the same technology.  Your magnetos are tired.  They just want to retire already, collect social security and travel the world in jet-powered airplanes, laughing at how they started all this flying rage.  Until then, they need help starting.  I would too at 104.  This is where our trusty Impulse Coupling comes to the rescue.  When the airplane is first attempting to start, the engine is turning very slowly.  This is problematic for the magentos which need a faster rotation to be effective.  The impulse coupling helps the start process by allowing the magneto shaft to build up energy, which is then released at the proper time to create that 20-30,000 Volt spark you need to get those 180+ horses working.  Ever have those wind-up toys as a kid that creates a cool looking spark when you release it and it moves all around the floor?  That is basically the same principle of the impulse coupling.  The next time you hear that click, you know what it is.

The Grounding Check
What is the grounding check for and why do we do it?  For some, it is because their instructor told them to.  Fair enough, but do you know why you are actually doing it and what you are checking for?  There have been several incidents (including some very local) where someone went to move a prop for one reason or another and the airplane started up, instantly killing the person.  The grounding check attempts to ensure that, when you power down the airplane, the chance of the engine restarting is nil.  When you turn the key from BOTH to OFF, you are grounding the P-Leads on both magnetos to ensure that they will not allow the engine to start once you pull the mixture to kill the engine.  Do you ever check grounding of the individual mags?  Can you?  While I grab a cup of coffee as you think about this question, think about your grounding check.  

When you are doing your runup, what are you checking?  You are checking each individual magneto to ensure that it will run independent of the other one should one of your magnetos decide on early retirement.  The only way for this to occur is for you to ground the other one.  So, when you turn your key from BOTH to L or R, you are grounding the other magneto.  The switch tells you what magneto you are actually running on, the opposite one being grounded.  

Putting it all together
Now that you have all of this amazing information, can you do anything with it aside from impressing your friends?  Let’s say you have a rough running engine on the ground.  Can you tell if it is a spark plug fouling or the entire magneto.  If you have an engine analyzer, it’s actually pretty easy.  When performing your run-up check and watching your EGT, look for a specific cylinder that has a lower EGT than the rest which will indicate a fouled plug.  This is the most common cause of a failed “mag check.”  If you have an entire magneto failing, you will likely see all of the cylinder’s EGT will be affected, not just one.

Mike Busch, A & P extraordinaire put out a great article on the Mag Check and you can dive more into some common troubleshooting that can be done if you experience some of these issues.  For now though, the next time someone asks you what a Magneto is, you’ll have a good answer!

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Plus One Flyers - Membership Agreement

Section A:  Agreement

I hereby certify that all the information on this membership form is true to the best of my knowledge.  I understand that any falsification shall be grounds for disqualification or forfeiture of my membership.  I have received, read, understand, and agree to abide by the Plus One Flyers, Inc. (the “Club”) Bylaws and Operational Rules.  In particular, I acknowledge that I have read and agree to be bound by Section 4.8 of the Bylaws, which states that I shall be responsible for any damages or abuse to an aircraft that I am using.  I also acknowledge that I have read and agree to be bound by Section 4.8.3 of the Bylaws, which provides that I shall not seek to hold Plus One Flyers, Inc. legally responsible for my acts while operating a Club aircraft which results in damages or injuries, whether to myself or others. I further acknowledge that I have read and agree to be bound by Article VII of the Bylaws, which provides that I shall be fiscally responsible for my dues, timely flight payments and any collection fees.

In the event that any damages are assessed against the Club as a result of my acts or negligence, I shall be solely responsible for the payment of those damages and for any legal fees or costs incurred by the Club in defending itself.  As set forth by Article VII in the Plus One Flyers Inc. Bylaws, each member, and their heirs, successors, personal representative and assigns, release, acquit, and covenant not to sue, and  shall indemnify, defend, and hold harmless the Club, its officers, directors, agents and employees for any liability, losses, or damages that I or the Club may suffer as a result of an act by, or negligence of, the member while operating a Club aircraft. Each member must acknowledge and agree that he or she is accepting and using any and all Club aircraft in a used, “as is” condition and that the Club does not and has not repaired, reconditioned, or maintained any Club aircraft.  Each member must agree to assume all risks, and assumes full responsibility for risk of bodily injury, death or property damage associated with any Club aircraft and not to seek to hold the Club legally responsible for any such defects in Club aircraft before being allowed to use and fly Club aircraft.

Finally, I understand, should I resign from the Club, my resignation notice (form) must be given in writing at least thirty (30) days prior to leaving the Club and that I will return my club key(s) on or before my resignation date, which is effective the 1st day of the next month following that 30 day period. Membership remains effective until terminated under the terms of this Agreement.

I also agree and understand that:

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E.     I will maintain and promptly notify the Club of any changes to my telephone numbers, billing address, email, and credit/debit card(s) information by updating this information myself in Schedule Master.          Initial here_________

F.     I will promptly notify Plus One Flyers if I am involved in an aircraft accident, even if it is not a Plus One Flyers Aircraft.

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I will promptly and regularly submit updated copies of my Medical Certificate and Flight Review to the Club’s Membership Officer.


Section B:  Automatic Payment and Credit/Debit Card(s) Guarantee

The credit/debit card(s) you provide on this form and/or in Schedule Master serve as your payment guarantee and is required in your Schedule Master Membership account to enable and maintain your airplane scheduling privileges. Plus One Flyers will charge your card(s) and email you an invoice for any payment shortages.  Any dispute regarding a charge can be handled by the Club Membership Officer.  If an error results in an amount owed you, Plus One Flyers will credit your Schedule Master account balance unless you request a refund check.

Membership Dues are $29.00 monthly, charged to your credit/debit card(s) or if available, against a pre-paid credit balance.  Paying Annual Dues means you maintain a pre-paid credit balance that is reduced by $31.00 monthly until zero and if you elect to continue to pay Annual dues, you are responsible for pre-paying the appropriate amount each year.  There is a $129.50 initiation fee for new members and renewing members, except for those members renewing while serving active duty in U.S. Armed Services.  If there is a change in dues you will receive a thirty day notice by email and a message will be posted in Schedule Master. Your account will be charged on the 1st of every month if you choose the monthly option.  An email invoice will be sent to you every month.  It is your responsibility to view your invoices/account to verify that your payment has been made.  You are responsible for ensuring your card(s) remains current and that if it expires or your billing address changes you alone are responsible for updating that information in Schedule Master.  If your bill has not been paid your scheduling privileges will be automatically suspended until it is paid.  If three consecutive dues invoices remain unpaid your membership will automatically terminate and a $99.00 initiation fee plus the past due balance will be required to reinstate your membership.  If you take no action your account may be sent to a collection agency.

Keep your billing address and email address and card(s) current in your Schedule Master Membership Account. Plus One Flyers is not responsible for ensuring your email system allows Schedule Master or other Club emails to reach you.  You will receive an automatic email one month prior to the expiration of your card in Schedule Master.  Plus One Flyers is a PCI-DSS-compliant e-commerce and POS credit card processing merchant.  See the Club’s Privacy Policy for more about how we protect your private information.                                                                                              

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