Airworthiness a read..

How to keep the Cessna 170 flying and airworthy.

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T. C. Downey
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Airworthiness a read..

Post by T. C. Downey »

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N2255D
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Re: Airworthiness a read..

Post by N2255D »

Article page 15 or PDF page 15?
Walt Weaver
Spencer Airport (NC35)
T. C. Downey
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Re: Airworthiness a read..

Post by T. C. Downey »

N2255D wrote:Article page 15 or PDF page 15?
The whole link is a PDF, hit the link, and scroll down to page 15.
voorheesh
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Re: Airworthiness a read..

Post by voorheesh »

Excellent article. However, the statement on page 17: "an alteration that affects weight and balance is a major alteration" is simply not true. To quote:

Appendix A to Part 43 Major Alterations, Major Repairs, and Preventive Maintenance; (a) Major Alterations; (xi) "Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft"

An alteration that affects empty weight and/or cg within an aircraft's certificated limits is not in and of itself a major alteration.

The regulations have to be read carefully. We should not read in elements or ideas that are not there. Magazine article such as this are very helpful to aircraft owners and pilots because they summarize basic requirements. They are not a substitute for the actual regulation.
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falco
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Re: Airworthiness a read..

Post by falco »

Yep
T. C. Downey
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Re: Airworthiness a read..

Post by T. C. Downey »

Did you notice who wrote the article? and who's publication it was in?

You'd be hard pressed to show a modification that does not exceed the published limits of the W&B change for a Major or Minor. I believe we have beat this dead horse already.
T. C. Downey
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Re: Airworthiness a read..

Post by T. C. Downey »

voorheesh wrote:Excellent article. However, the statement on page 17: "an alteration that affects weight and balance is a major alteration" is simply not true. To quote:

Appendix A to Part 43 Major Alterations, Major Repairs, and Preventive Maintenance; (a) Major Alterations; (xi) "Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft"

An alteration that affects empty weight and/or cg within an aircraft's certificated limits is not in and of itself a major alteration.

The regulations have to be read carefully. We should not read in elements or ideas that are not there. Magazine article such as this are very helpful to aircraft owners and pilots because they summarize basic requirements. They are not a substitute for the actual regulation.
What does that statement mean to you? Did your modification change the empty weight of the aircraft?

What is the Empty weight limit of any aircraft?
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Bruce Fenstermacher
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Re: Airworthiness a read..

Post by Bruce Fenstermacher »

T. C. Downey wrote:An alteration that affects empty weight and/or cg within an aircraft's certificated limits is not in and of itself a major alteration.
Tom, first I don't quite understand the purpose of the red type in your first quote of Vorrhessh. Perhaps if was not as you intended, maybe you made no attempt to make type red in it. No matter you must read the sentence as a whole.

It says to me that an alteration that adds weight without exceeding the aircrafts certified gross weight limit or certified CG limits, by the addition of the weight itself, is not a major alteration.

Yes like many FARs, it appears to be worded poorly because it talks about empty weight confusing the issue. Our 170s can have an empty weight between 0 and 2200lb depending on the cg at the upper limits, and be within certified weight and CG limits. And meet the criteria of the statement.

Interesting, many of the helicopters I fly can not meet this statement because there is a stated minimun weight above 0 which they don't meet or the empty CG is outside the limits to start. We are required to load these aircraft correctly to shift the weight and CG inside the limits to fly. Many smaller pilots say 140 or less actually have to fly with a sand bag when no other crew is on board in order to achieve limits.
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Bruce Fenstermacher
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Re: Airworthiness a read..

Post by Bruce Fenstermacher »

Tom's point, that this is an FAA publication and it does have a statement that when taken literally is not completely correct, is understood. And I think when ever possible such half statements shouldn't be made.

However it is certainly understandable because to go into detail for such an article would be simply rewriting the FARs, which is not what this article is intended to be. Remember, the entire publication, is not approved or regulatory.
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T. C. Downey
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Re: Airworthiness a read..

Post by T. C. Downey »

My point was, the article misquoted the actual FAR which says

"(xi) Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft."

When the author places a " and/or " in his statement it changes the meaning of the FAR and typical of some inspectors belief that either an empty weight change "OR" a change of CG will be a major alteration.

My intention in linking this article was to show the guidance the FAA gives us in evaluating airworthiness during a preflight.
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