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Answers To Frequently Asked Questions: Show all FAQ'sGeneral

 

Why ask a question? Owner maintenance? What is Mogas? Courtesy Car Physical exam Oil change schedule Weight-shift-control aircraft Q: Why ask a question? Why would I ask a technical question on this website? A: Because all questions are answered by a very competent certified professional - and the service is free. Why wouldn't I ask a question on this website?    Q: Owner maintenance? As an airplane owner, am I allowed to change a switch on the instrument panel? A: Well there are a couple of qualifiying questions, first are you an A&P mechanic and if not is this airplane a home built/experimental airplane built by you? If the answer is no to both than you must visit FAR 43.3 par G. Assuming you are a holder of a pilot certificate under Part 61 you may perform preventive maintenance. Now you must visit FAR part 1 Definitions and Abbreviations, And it says Preventive maintenance means simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations. My opinion is that a switch on an instrument panel is a complex disassembly assembly operation, so no you cannot do the work yourself.    Q: What is Mogas? What is the difference between Mogas and 100LL? A: Jean, Hi! I have heard a few people use the term Mogas and I believe they are refering to Auto fuel. The difference between Auto fuel and 100LL is pretty significant. First of all the Auto fuel used in airplanes can not have alcohol in it. I have had quite a few airplane owners who use Auto fuel complain of water condensing in the tanks. Now 100LL is manufactured to a very strict aviation standard with lead added, aviation fuel also gets very careful handling to insure octane rating. I'm sure Auto fuel does not get the same treatment. Auto fuel costs a lot less than 100LL. I always look at Auto fuel as just that, with Auto fuel if you get a bad batch you just coast to the side of the road, unfortunatly you can't do that in an airplane.    Q: Courtesy Car Question from Phyllis: When you use a courtesy car from the airport, why do you pay fuel for the airplane instead of gas for the courtesy car? A: The life blood for those FBO's is the income they make off of Aviation fuel both 100LL and JetA and tie down fees. The courtesy car is an after thought and by the way might be a 1968 Buick Rivera running on three cylinders or a 10 pasenger van with a video screen. Pilots just automatically put a few bucks in the tank before returning it - returning the courtesy you might say.    Q: Physical exam Question from Mary: Mike, Is it necessary to have a physical exam to be able to learn to fly? And, if necessary, can I use my family doctor? A: Two answers, first, if you want to fly what is called Light Sport aircraft and you have a drivers licenses you do not need a physical. Now to fly a certificated airplane you need to get a medical certificate from an AME (Aviation Medical Examiner). Your family doctor may be one, if not, He or She could tell you where to find one.    Q: Oil change schedule Question from Jim: What do you recommend as the interval between oil changes? A: This is a question that has many answers. It depends on how the aircraft is being used, what kind of oil is being used, what type of filter if any is installed,and so on. Care and maintenance of an aircooled engine is challenging, internal corrosion caused by moisture, residue(carbon , lead) from combustion cycles (100's of thousands between oil change). Another factor is how is the airplane stored between flights? I think 25hrs is a good interval, 50hr if the airplane is flown regularly, and for mineral oil 25hr. This is a question that has many answers. It depends on how the aircraft is being used, what kind of oil is being used, what type of filter if any is installed,and so on. Care and maintenance of an air-cooled engine is challenging, internal corrosion caused by moisture, residue(carbon , lead) from combustion cycles (100's of thousands between oil change). Another factor is how is the airplane stored between flights? I think 25hrs is a good interval, 50hr if the airplane is flown regularly, and for mineral oil 25hr. You also asked about whether oil changes can be accomplished by aircraft owners, which is a good question. Opinion varies on this. Is it complex or is it simple? I think this comes down to the same conclusion anthropoligists reached after observing a troop of chimps. The fat ones had learned how to use tools (sticks to dig ants out of holes, rocks to crack nuts and so forth). The skinny ones sat around and waited for a banana to fall out of a tree. The conclusion was some chimps have a natural ability to use tools and some don't. Some airplane owners are capable, some are not. My opinion is that the only thing about an oil change that can be considered mildly complex is the the safety wire on the filter.    Q: Weight-shift-control aircraft One of the 'types of aircraft' on the FAA master list is called 'weight-shift-control'. Can you clarify, what is that type of aircraft? Jim A: Jim, I was expecting to have to go through page after page of FAA certification and technical data to get this answer. But it turns out you have to be a flyer of LSA or Trikes to appreciate weight shift control. A fixed wing flyer has hard limits on cg (unless you fly an aircraft with an active cg like a Concorde or 747-400 ie: moving fuel forward in the case of the concorde to attain super sonic flight). But LSA and Trike drivers use the weight of their bodies and in some cases their passengers bodies to determine the optimum cg by weight shift control. Shift back to climb, forward to decend. Fly safe.