Conversion Manuals -building a plane and trying to save the wrong $75.


If you were one of the people who thought the tone of my last story was a little harsh, let me share a little insight: I have been getting about one ‘special person’ a day lately, and the letter here Who is responsible for the parts we use? is just a sample of the kind of special stuff arriving lately.


Try this: A person in El Paso who sent in the distributor with the cut wire in this story: Ignition “issues” and I-U-S-F , who claimed it was defective although it ran fine, when directly questioned about some information he was missing, said that he made the choice that he wasn’t going to buy a conversion manual from me. His plan was to only buy the parts, and save the $75. His reason was that he was just going to read stuff on line and on my website.


Although he is building a Pietenpol he had never heard of my Corvair – Pietenpol Reference page,  Guest Writer: Pietenpol builder/flyer Kevin Purtee nor the Colleges he and Shelly put on in the same state, nor our Piet Vair discussion group update, notes on joining. So much for getting all the information needed.



Above is a sample instruction sheet that comes with all of our parts, including all the ones the person in El Paso purchased. The lines in yellow plainly state that you can not use the parts without a manual and have it be airworthy. Ask yourself, who reads this on all the sheets, and still thinks it is a good idea not to buy a Manual? Perhaps the man objected to my lavish $10/hr life style, and felt that it justified any action he might take to save $75. Your guess is as good as mine, as I have no understanding of that approach to aviation and expecting success.




Who is responsible for the parts we use?


I received the following letter in the comments on my short article: 1960, A great year of American manufacturing.  I have met the writer Mike McKosky, and he is obviously concerned about the issue he brings up in the letter, so I thought I would directly address his thoughts here rather than in the comments section of the Colt story:


Mike’s Letter:

Interesting article.
With regards to stuff being made in America, in years gone by, and not wanting to buy anything Chinese or generally Asian:

I recently bought a set of crankshaft main bearings from Clark’s. I did try to buy Clevite main bearings, was able to buy only the Clevite rod bearings . The main bearings are made for, not by, Clark’s.

I spent a fair amount of time trying to find Clevite main bearings, was not successful. Did ask around as to what was available, and in particular what Corvair mechanics were using, and asking who the manufacturer was.
When I asked the person at Clark’s sales, she had no idea where the bearing were made, and did not seem too interested in finding out for me.
The only outfit that was able/willing to tell me were the Clark’s main bearings were manufactured was California Corvair, the individual (forgot his name) was very quick to tell me, even after I told him that I was just gathering information, not buying. It was as I suspected, made in Taiwan.

I have no problem generally with Taiwanese manufactured products, mostly based on gut-feelings. I have no technical or rational basis for that, just based on impressions. The Taiwanese are, according to my simple research, very well educated, highly technical, and probably very dependable.
But, I don’t really know.

I did order, and received, the set of Clark’s bearings ($93.50 not counting shipping).
The outside packaging, a box, has one statement on the end tab with the info:
Engineered & manufactured Exclusively for Clark’s Corvair Parts
Genuine (what looks like a stylized symbol) GN Parts D0516

Elsewhere on the outside box it states:
Premium Bearings
Original Parts
Quality Products
Engineered and Manufactured
by Original Equipment

It also says, as a stylized symbol:
Quality Assured Firm

And also:
QS-9000 Certified and Approved

On the internal package the bearings are stamped with technical data, with the stylized symbol GN.

From Wikipedia, “QS-9000 is a quality system standard that focuses on helping automotive suppliers ensure that they are meeting/exceeding automotive customer requirements”.
I have yet to read in detail, but thus far I don’t think it is an ISO standard.

So, who manufactured the part?
Where was it actually manufactured? (had it been outsourced to an outfit in mainland China?)
What is the technical relationship to the original GMC bearing for the Corvair engine?
What documentation does anyone in the Flycorvair/Sports Perfomance Aviation complex have to trace the manufacture and testing of the bearings with regards to wear, materials, life-span, and whatever else would be relevant to main bearings that are used on car/aviation engines?

Dan claims that he has used the bearings, and has flown aircraft for a long time that used these bearings and finds that these Clark’s bearings hold up okay. Although I am very much inclined to trust Dan, the comment from one of Reagan’s speech writers always occur to me in this kind of situation “trust, but verify”.

So, how does one verify that these bearings will serve the application properly?
What is your commitment to the use of these bearings?
Do you have documentation that shows source, quality control, country of origin and manufacturer in Taiwan?

I am motivated to know these things for a few reasons, amongst which are:
1. After a few years of arguing that Asian products, especially Chinese, are to be avoided, are we now to accept such products?
2. Is there now an acceptance of Asian-made tools, like torque wrenches?
3. Is there a process used by William Wynne and associates to verify such products?
4. At the core of a Corvair engine, the whole thing rests on the main bearings. This seems to be the foundation of a reliable engine, failure of main bearings means the failure of the whole engine, and possibly failure of the airframe, and maybe the failure of the pilot and co-pilot or passenger, and maybe failure of the lives of the people that the failed system descends upon.

Well, okay, maybe the foregoing is overly dramatic, but it does serve to convey my concerns. In the short term I am concerned about the possible loss of between $8000 (present parts cost) and $12000 (final costs?).

Any useful, insightful, comments?




My Response:


My words about the bearings are exactly the same as Dan’s. We have put them in engines, studied their installation, and found them to work satisfactory for us. You are correct that Clark’s as a matter of policy, does not reveal the sources of parts. It is a reasonable assumption they are imported. You have done homework, asked questions, and found what we know, which is they work.

Answering your four questions backwards:

#4- I know of no failures of these bearings. I think your claim “they are the foundation” implies they are the highest stressed part, which they are not.

#3- I do not ‘verify’ any part, other than to use them as we describe, and report the results. I am not in the certification business, nor do I offer warrantees or guarantees, expressed nor implied, on other peoples products.

#2- No. If you called and asked if you should put your engine together with a Chinese made torque wrench, I have the same evaluation process on the bearings, which is I have seen people try it, and the wrenches are not accurate, so they don’t work as I intend. Have you seen anywhere in my comments that I now suggest using Chinese tools? Perhaps you jumped to a large conclusion?

#1-I don’t know where the bearings are made. I do avoid imported parts when any good domestic option is available.

Your letter carries an implication that it is my personal responsibility to insure the quality of every nut and bolt I mention using in any of my writing. THIS IS NOT MY RESPONSIBLITY. THE CHOICE TO FOLLOW MY EXPERIENCE IS YOURS. YOU ARE 100% IN CHARGE OF BUILDING YOUR PLANE. I have never implied that I have the power or ability to ‘verify’ or materially evaluate every part any builder will use. Thus your engine is 100% your responsibility.

Mike, I trust that through simple observation, you have been able to comprehend that I do not posses the same resources as Pratt-Whitney, and hopefully you understand that it is ludicrous to express the same expectation of me that one might of Pratt-Whitney. They make certified engines, I do not. Pratt-Whitney made about 2 Billion dollars in 2014, the same year I worked about 2,600 hours and made $26,000. Now, just think how stupid your letter sounds to me, implying that I should be using all my excessive wealth to track down and monitor the output of a foreign bearing manufacturer to appease your personal need for some type of guarantee.

Here is what builders are entitled to expect for their fractional contribution to my $10/hr wage: They can expect me to tell the truth about my experience with the parts and systems I discuss. That is it, period. Anyone who really wants to build a Corvair powered plane will find that an outstanding value. People like yourself, looking for a guarantee, should get out of experimental aviation, because your letter shows that you are not willing to take 100% responsibility for your project.

I appreciate beyond words the support and patience of builders and friends during the last two years of my father’s life, when I spent as much time with him as I could. I was putting in one of those $10 hours in the shop when my sister in law called and said come right back to NJ. I bought a direct ticket, but with an hour to go, United canceled the flight. Took 14 more hours to get there, I was the only family member not present when my father passed. This leads to questioning what I have done with my life. For the most part I tell myself this mantra “I have done honest work. I have treated people fairly. I am privileged to know many good people.” Sometimes this works and I am ok, and other times I read some stupid fucking letter like yours with it’s implication that I owe you a guarantee and I have some mislead you, and implying  I am now about to endorse Chinese tools, and I think it was all a giant fucking waste of time.