Can’t read instructions?


To even apply for an aircraft mechanics license in the United States, The applicant must swear to and demonstrate they can read, write and converse in English. There is a very good reason for this. The instructions on how to work on planes are all written in English, and people who can’t read English can’t follow directions and do safe work in an English speaking system. Non aviation people might want to have some kind of “bias examining encounter group with safe spaces and neutral pronouns” but I’ll bet they wouldn’t want to take an airliner to such a conference if they were told the mechanics who just worked on the plane couldn’t read the maintenance instructions.


Here is a more practical problem I deal with: I have a number of builders who evidently can’t read English, or if there are too many words in a story they think it is justification for not following the content.  I have no sympathy for this. The average A&P mechanic with 25 years of experience, like myself, earns a whopping $36K /year. (Yes, the professionals who worked on the airliner that took your family to Disney World last year are paid less than your wife’s hairdresser.) And for this salary, they are willing and able to read the most convoluted Air-worthiness Directives, Instructions which are the mutant products of the FAA, Lawyers and Engineers, all to protect the safety of people they will never meet, people who’s sole criterion for selecting a ticket was how cheap they could buy it.


And that is why it stuns me that a guy who is fully planning on flying himself, his wife, his kids and his grandkids in a plane, can’t force himself to read a few paragraphs in English and follow the directions they contain. A&P mechanics do for strangers, what these people will not do for their own blood. Before anyone suggests that A&P’s are professionals, just remember that Physics Chemistry and Gravity don’t have a different set of laws for homebuilt aircraft, all the work on flying planes must be done to standards.



So, Lets look at an example form the previous story, about someone who either can’t read English, or has an attention span that didn’t carry them through 3 pages of instructions in big print with pictures. If you are a Corvair builder, what is wrong with the oil pressure sender above, besides the fact it is completely overloading the 1/8″-NPT threads?



The correct answer is the sender isn’t even screwed into the correct hole for pressure. The 3 pages of  instructions that are shipped with every Gold Oil filter housing clearly state the temperature sender goes in the 1/2″-NPT port, and the pressure sender goes in one of the two 1/8″-NPT ports.  That is just plain English. The guy who sent the picture to my friend reversed this. Result? He will be reading falsely high oil pressure, and falsely low oil temperature.  Give him an adjustable oil pressure regulator, and he will crank it down until he starves the bearings of oil; On cold days he will wait forever for the oil temperature to reach acceptable levels. On hot days he will have no real idea how hot is oil is. Who’s fault is this? It is 100% the fault of the guy who couldn’t be bothered to read three pages of big print and pictures to protect his family.


The really ironic part was the person who made the contraption was writing my friend because they noted the sender instructions required it point upward. So they followed the instrument makers instructions, but not the guy who wrote the book on the engine. Make sense of that.



I am sure there will be several people who claim they were justified in ignoring the directions because the sender their “glass cockpit” company sent wouldn’t thread in the hole I told them to put it in, so they stuck it in a different one. Here is reality: Top left is a common electrical temp sender in 1/8″-NPT. To put it in the 1/2″ NPT temp hole requires one AN-912-6D bushing, page 110 in the Aircraft Spruce catalog, it is going to set the builder back a whopping $6.50. That is what is pictured in the middle. The end is a brass version of the same idea with a temp sender in it, but I ripped it out of a plane because it is a dumb idea to have a Chinese fitting that weighs three times as much as it needs to in your plane, and probably costs the same.



If anyone consistently finds themselves missing simple instructions like the ones above. Seriously consider making a concerted effort to find out why, and how to bring more attention to bear. Do this now, in the building phase, because the later flying phase has very harsh penalties for people who make a lot of mistakes and have trouble following operational instructions.


If anyone thinks missing instructions or not following them is justified because I don’t write in short enough sentences, They should PLEASE, write that to me in an email. Because one day, when something bad happens, I’m really going to appreciate having that letter when the FAA, their insurance company or the lawyer their wife hired calls.


If this tone sounds offensive to anyone, stop and think of this: What if you had a 25 year family business, and some people never read the instructions you carefully wrote sent, and taught for free. How would you speak to such people if you had plenty of evidence that a good number of them were willing to take 0% responsibility for the outcome of their choice, and some of these people felt perfectly justified in hiring lawyers to lie on their behalf in an attempt to rob you?  What if you were raised under these ethics: Values of my Father. What tone would you have?  I firmly believe that people have a right to destroy their own lives. I just don’t believe that they can later hold other accountable for their choices, but obviously we have plenty of people in our country who find nothing wrong with that.




9 Replies to “Can’t read instructions?”

  1. Does the AN-912-6D bushing also change the temperature reading? I would assume that since there are not one, but two thread joints for the heat to pass through, and additional mass to heat up because of the bushing that the reading would be slower to heat up or cool down.

    1. Dan, the sender body being in the oil flow is all that counts, the housing is essentially the same temp at the oil because it has 2 gallons of it per minute flowing through it.

  2. I was wondering if the subject of that port being designated for the oil temp sensor was going to come up, I did read the instructions and it left me scratching my head. For my own I needed a bushing to make it fit, there are such a wide variation on direct and electronic senders out there but you made the port big enough for whatever comes along apparently and AN bushings are cheap.

  3. Philosophical comment – I have owned a bonded-metal certified airplane, built a riveted metal airplane from a kit (and installed a Corvair motor in it), and now own a plans-built wood airplane. The mechanical expertise required for each “epoch” in my aviation skills development is different. Personally, I enjoy the education and challenge that was the original reason for creating the experimental-amateur built category. I feel the risk is manageable.

    But I understand that this is not for everyone. The development of the erector-set style kit a la Van’s, with very detailed instructions and matched-hole parts, has made the E-AB category accessible to a huge number of folks who still face a major challenge but would otherwise be excluded. The “factory-assist” and semi-professional builders have pushed it pretty far from the vision of the founders of the EAA.

    But the level of skill in the amateur-built world varies immensely. There are E-AB aircraft out there that I would never fly in, despite the base design being solid. Similarly, there are E-AB motors out there that I would never fly behind. In the particular case of the Corvair, IMO William has done a magnificent job making this option available to the amateur builder. If the instructions are followed judiciously, you get a reliable motor that will not break your pocketbook to operate.

    If you don’t follow the instructions carefully (something I’ve been known to do), you’ll very probably get a less reliable motor. But that is both the core nature of E-AB, and the conundrum that vendors serving the industry have to resolve. Can they, in the modern legal environment, and without undue risk to themselves and their families, reasonably provide their product to us?

    I personally was caught up in the 601XL wing fiasco that might have put Zenith out of business. Zenith may have over-estimated the skill set of the average builder when they entered the mass-produced kit market. Zenith chose to “play ball” with the NTSB & FAA and is still around. The owners of well-built and well-proven 601XLs were effectively forced by the insurance companies into major rebuilds.

    Van’s recently got out from under an aggressively and publicly pursued (and meritless) lawsuit that cost them years of travail and lots of money. The suit, brought by the mother of a 4-year-old killed in an RV-10 accident, clamed that Vans “Exploits (a) regulatory loophole to mass-produce “kit” airplanes while avoiding critical design, safety, and airworthiness requirements.” 2 years later the lawsuit was dismissed, but who knows what long-term damage was done to Vans or to the E-AB community in general.

    So… Everyone please appreciate and defend the all work the WW and his RDT&E team have done and continue doing, his support staff (Grace & ScoobE!), and the folks who host the *free* Corvair colleges, and as well as the folks at SPA, LLC, who have helped “standardize” the Corvair flight motor parts and made it easier to acquire and build. Their risk in not negligible.


  4. I am astounded WW has had to keep writing these rants. But clearly he does. I would have thought the type of person who decides to build their own plane and plane engine, has decided to do all sorts of similar things on their own and been through the process of learning highly technical knowledge informally and recognize that every scrap and crumb is vital. That attempting to do what normally takes a formal education followed by apprenticeship journeymanship and mastery could not possibly be winged with the half assed approach WW keeps describing. However its clear hes telling the truth because i recognize the type I am just astounded they exist in experimental aviation.Well if they kill themselves they were certainly warned. I think hes right people cant read wont read I have found every endeavor i have attempted i end up better informed than the masters i at first seek knowledge from and its always few people out of academia will read the damn science.

  5. I have a question William, If one wanted to put a oil pressure switch in to say activate a hobbs meter would the best way to do that be to use a T with the 1/8 NPT and put the mechanical pressure gauge on one side of the T and remote mount the switch and run a line to it from the other side of the T? And I want to also tell you that our litigious makes me as sick as it does you. If more people would take responsibility for their own actions maybe it would not be that way? Good article. Thanks

  6. And I want to also tell you that our litigious society makes me as sick as it does you. If more people would take responsibility for their own actions maybe it would not be that way?

    1. David, just look at the Suit against Cessna and Lycoming, that was responsible for Cessna not building a Non-Commercial Single Engine aircraft for a Decade, When they did come back, it was at a price point of 220%, which has steadily increased because of Liability Insurance premiums. it took the price of a new Aircraft from that of a high-end Sports Car, to that of a Home….or in some areas of the country Twice that of a Home. For an accident that was 100% Pilot Error (Controlled Flight into Terrain)

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