top of page

Block Lesson One

Course Instructions

We have found people learn in different ways. Some learn better by reading the material themselves, others by watching a video. Throughout our Blocks we have the course set up in two different ways; 

  • The first is a video you can watch with text to speech. The video is an MP4 which is not interactive. There is no capability to link anything. That being said, any part that requires you to interact with, you will need to find the link in the text, or watch another video further down the page.
  • The second part is set up with text you can read with all FARs and documents linked to the FAA’s website. Everything is interactive. When it is time to interact with the FAA’s website, or watch another video the capability is there for you.

You can choose which way you would like to precede. 

NOTE:  Each block covers specific FAR information in chronological order, and it is recommended that you work through them in that order. However, you are free to work through them in any order you wish. These Block Lessons are FREE to anyone to read, and work through as often as you would like, all year round. The course can also be used as a TRAINING TOOL so that everyone in your organization is following the same processes.

If you would like to use this course to meet the 8 hours of learning required by FAR 65.93, you are required to complete ALL 8 blocks of Learning, and then take the Final Quiz. About 65% of the questions on the Quiz can be found in these block lessons, the rest you should know. Some of the questions on the quiz can only be answered by going through the course. The Quiz consists of 96 questions and you will need 70% to pass. If you don’t pass the quiz the first time, you will be able to take the Quiz again at any time. Once you start the Quiz you can pause it at any time, in order to search for information on the FAAs website, or review one of our Block Lessons. Once you have completed the Quiz and received at least 70% correct, you will be able to print a certificate to then submit to the FAA.

At the end of Block One there will be a video demo you will need to watch and then read along with the reference on the FAA's website. There will be questions on the quiz related to the narrative on these Demos.

Welcome to Block Lesson One 

Hello, I am Peter Friedman.

I’m a certificated aircraft mechanic with an Inspection Authorization. In 2016 I received the FAA's Charles Taylor 50-Year Master Mechanic Award. I’ll be your guide throughout the "Inspection Authorization Refresher Training" seminar.  When you complete all of the course content, you’ll receive your renewal certificate.  

Before we begin I like you to know, that regulations in this course are referred to as FARs, Federal Aviation Regulations, but the actual legal references are found in, Title 14 of the Code of Federal Regulations, CFR.

Block Lesson One Will Cover

Block Lesson One Video

Inspection Authorization Refresher Training Lesson One.

Ten years ago, after conducting IA Seminars for twenty years, I created this FLOWCHART that literally will answer ANY question you might ask related to aircraft maintenance! Each time I conducted a Seminar I challenged the IAs to ask a question, and if I could not answer it with the FLOWCHART I would buy them dinner! I have NEVER had to pay off!  Just follow the FLOWCHART from right to left, based upon what your question is, to arrive at Airworthiness!

For a product or a part to be considered airworthy, two separate conditions must exist at all times:
             (1) it must be in a condition that assures its safe use during flight and,
             (2) it must adhere to the type certificate holder’s drawings and specifications.
  • The Type Design is defined by the Type Certificate Data Sheet, Airworthiness Directives, Aircraft Flight Manual ,or Pilot’s Operating Handbook for older aircraft, the Illustrated Parts Catalog, and the required Equipment List (describes what is required to be installed on the aircraft).

  • If the parts/product are not original equipment, have alterations been made?  Alterations alter the Type Design.

  • Type Design can be altered in four ways:
          (1) a Type Certificate Holder can alter their product;
          (2) by a Supplemental Type Certificate;
          (3) by a Form 337 FAA field approval;
          (4) and by an Airworthiness Directive.

  • If Type Design was altered by any other method, it is not an approved alteration.  As such, the condition for meeting the product/part’s type design is not met. The product is not considered airworthy!

  • For a product/part to be airworthy, the two conditions and all of the sub-factors must be in agreement and in sync. If one of the sub-factors produces a negative answer or is out of sync, then the corresponding condition fails. The product/part is not considered airworthy. If all of the sub-factors produce a positive result and are in sync, then the corresponding condition passes. The product/part is considered to be airworthy.

  • You can check out the Airworthiness Flowchart Video at the end of this page!

General Definitions

Now let's take a look at the General Definitions. You can open another link FAR 1.1 to 1.3 to the Definitions on the FAAs website,, to follow along.

FAR 1.3   Rules of Construction.

 "Shall", and “Must”, are used in an imperative sense;
"May", is used in a permissive sense to state authority or permission to do the act prescribed.


Who is the "Administrator"?

As the FAR states, it could be the actual Administrator of the FAA in Washington, D.C., or any entity to whom a designation has been given by the "Administrator".

What is an “Aircraft”?

It is any device that can be used to achieve flight in the air. It could be an airplane, a helicopter, a balloon, an airship, or a glider.

What is an “Airframe”?

An airframe is any structure of an aircraft not including an engine, propeller, or appliances.

What is an “Airplane”?

It is a fixed-wing device, with or without an engine, such as a glider, that is intended to be used for flight in the air.

What is an “Appliance”?

Appliances are the same as Accessories.

They include everything other than an airframe, engine, or propeller such as avionics, instruments, and the like. It is interesting to note that the word accessory is not defined by the FAA, only the word appliance as a synonym. It is also interesting to note that FAA certificated repair stations are issued Accessory Ratings, not Appliance Ratings.

What does “Approved” mean?

The word approved means that whatever is involved has been approved for aviation use by the Administrator.

The word approved means that whatever is involved has been approved for aviation use by the Administrator. Like real estate, the approval must be in writing to be legal. Approval can be issued by Administrator’s Designees, such as a DER, but it must be in writing and it must state that it was FAA Approved, nothing less. The person approving must be legally entitled to issue the approval as well. Data indicating approval by any person other than the Administrator, such as a Canadian DER, is not lawful to use to maintain or alter a US-registered aircraft

What is a “Civil Aircraft”? 

A Civil aircraft is one that is regulated by the FAA and has a US Airworthiness Certificate issued to it.
Aircraft used for personal and business purposes, such as transporting goods or passengers, rather than for military purposes. 
They are the opposite of Public Use aircraft, which are usually operated by governmental agencies such as the US military, or Federal, State, or local governmental entities such as police departments and the like.

What does “Fireproof” mean?

Fireproof means that whatever is involved can withstand direct fire as good as steel.

When the FAR requires a fireproof dataplate on both the fuselage and engine, it can not be made of aluminum, brass, or other material inferior to steel.

What does “Flame Resistant” mean?

Flame resistant means not having the ability to continue to burn, beyond safe limits, after the ignition source is removed.

This is very important when choosing fabrics and other materials to either repair or alter cabin interior headliners, seat covers, carpeting and the like.
As long as smoking is not allowed in the aircraft, and appropriate no smoking placards have been installed, the interior materials only need to be flame resistant.

What does “Flammable” mean?

It means, with any actual ignition source, it will immediately catch on fire or explode.

What does “Flash Resistant” mean?

It means that material will not burn burn violently when ignited. Oil and AVGAS are not flash resistant.

What is an “Instrument”?

An instrument is generally any appliance that supplies specific information to the pilot with respect to operation of the aircraft. 

These include gages such as airspeed, engine, oil pressure, oil temperature, attitude indicator, altimeter, compass, and the like whether or not it is an analog-needle type indicator or a digital display. Radios are not instruments.

What is “Maintenance”?

The word maintenance as defined only includes inspection, repair, overhaul, and the replacement of parts. 

It does not include alterations, which change type design. Understanding the term maintenance can be very critical when defending a violation – were you performing maintenance or were you performing an alteration? Always remember, maintenance as defined relates to performance that restores a product to its originally-designed condition. An alteration changes the product’s original design. Also remember that the design belongs to the Type Certificate holder.

An example of a Major alteration would be changing the engine in a cessna 172 to a Mercedes-Benz engine

What is a Major Alteration?

Simply put, it is any change in the original type design that, if not accomplished in accordance with FAA-approved data, could lead to a loss of life. Under the definition it says any appreciable difference. The word appreciable as defined in the dictionary means noticeable. Therefore, if a person can notice a difference between the original design and an altered design, it becomes by definition a Major Alteration.

All Major Alterations must be accomplished using FAA-approved instructions – no exceptions. AN IA can only accept a Major Alteration if the instructions used have been verified as FAA-approved, and the alteration had been accomplished in accordance with the FAA-approved instructions. AN IA is not legally entitled to approve Major Alteration instructions. FAA Advisory Circulars 43.13-1B and 43.13-2B may be used as F.A.A-approved data with some exceptions.

Note: FAA Advisory Circular 43.13-2B has an exception as to when it can be used as FAA approved data: This advisory circular contains methods, techniques, and practices acceptable to the Administrator for the alteration of non-pressurized areas of civil aircraft, only when there are no manufacturer alteration instructions.

What is a “Major Repair”?

A Major Repair is similar to the scope of a Major Alteration in that it must be accomplished using only FAA-approved instructions. It is different from a Minor Repair in that if it is not accomplished in accordance with FAA-approved data, could lead to a loss of life. Most Major Repairs are accomplished in accordance with Structural Repair Manuals, and most of these are automatically FAA-approved when they are published by the Type Certificate holder. However, some are not, or portions of them are not such as the manual published by Gulfstream and Cessna. In some cases the FAA AC43.13-1B publication may be used as FAA-approved data. Always remember that a repair by definition restores a product to its original type design condition. To determine whether or not you are involved with a repair or an alteration, you must decide whether the work to be done restores it or changes it?

What is a “Minor Alteration”?

By definition, a Minor Alteration has no appreciable effect on the product. It is the opposite of a Major Alteration. An example might be replacing solid rivets with blind rivets as long as the alteration is not structural and appropriate FAA-acceptable instructions are used. FAA-approved instructions are not required for Minor Alterations. You should always consult the Type Certificate holder’s maintenance manuals for acceptable Minor Alterations, or FAA AC43.13-2.

What is a “Minor Repair”?

By definition, a Minor Repair has no appreciable effect on the product. It is the opposite of a Major Repair which requires appropriate FAA Acceptable Instructions.

An example of a minor repair to a Piper Comanche fuel bladder would be to, remove the bladder inspect it, cleaning it thoroughly inside and out, and resealing it and patching leaks using 3M Scotch-Weld EC-776. Remember,  FAA-approved instructions are not required for Minor Repairs. You should always consult the Type Certificate holder’s maintenance manuals for acceptable Minor Repairs, or FAA AC43.13-1B.

Who is a “Person” when this term is used in an FAR?

By definition a Person can be any entity such as an individual, repair station, manufacturer, or any other entity to whom the FAA has designated for the situation involved.

  • Individual
  • Repair station
  • Manufacturer
  • Any other entity

What is a “Public Aircraft”?

A Public Aircraft, or Public Use Aircraft, is any aircraft that is owned, operated, and maintained by any governmental entity such as the Military, or any Federal, State, or local law enforcement agency.

Public Aircraft are not regulated by the Federal Aviation Administration as they do not have airworthiness certificates issued to them. They must, however, abide by certain flight operational regulations and restrictions. 

An IA has no involvement whatever with a Public Aircraft.

What is a Small Aircraft?

By definition a Small Aircraft is any aircraft having a maximum gross takeoff weight of 12500 pounds or less.

An I.A. can only perform Annual or Progressive inspections on Small Aircraft that are U.S. registered. Examples of small aircraft include Cessna, the entire range of propeller driven aircraft from the Cessna 120 up to the Cessna CaravanPiper, all models including the Chieftain, Beechcraft, the light models such as the Baron, and many foreign built small aircraft imported into the U.S.

Many aircraft used commercially for freight, sightseeing, photography and scheduled flights are small aircraft.

What constitutes Time-in-Service?

This is one of the most critical definitions for an IA. By definition Time-in-Service is that time between an aircraft’s wheels leaving the ground and when next the aircraft’s wheels touch the ground. Time-in-Service is vitally important in the FARs and to an IA when accomplishing an Annual or Progressive inspection. FAR 91.417 requires each aircraft owner or operator to assure that Time-in-Service is appropriately recorded in the aircraft maintenance records for each airframe, engine, and propeller – all type-certificated products. It is commonly known, especially on single-engine, fixed gear aircraft, that keeping Time-in-Service using the tachometer or Hobbs meter is not legal. The manufacturers of tachometers admit that the time on a tachometer usually is seven to eight percent ahead of actual Time-in-Service, and Hobbs meters are usually ten to twelve percent ahead of actual Time-in-Service.

This is especially critical when there are recurring airworthiness directives involved or life-limited parts subject to Time-in-Service.

An example might be a one-hundred hour recurring inspection requiring disassembly of parts, non-destructive testing and the like. If Time-in-Service is being recorded using a Hobbs meter, such as used by rental aircraft operators, expensive recurring inspections might be accomplished at ninety hours each time instead of the required one-hundred hours Time-in-Service . Further, an aircraft with Hobbs’ recorded time of five thousand hours may actually only have forty five hundred hours Time-in-Service, which might impact the resale value of the aircraft.

What is “FAR Part 21”?

FAR Part 21 defines the applicability of this Part to the FAA certifications and procedures for type-certificated products such as aircraft, engines, and propellers, and parts of those products. It also details the procedures required for approving alterations to those products. It also covers Part Manufacturer Approval or PMA, and TSO parts or TSO.

What Constitutes an Aircraft “Type Design”?

By definition the Type Design includes all of the drawings and processes necessary to define the structural integrity of the aircraft, and includes a listing of all design data to define the FAA-approved configuration of the aircraft. In short, Type Design includes every manufacturing production drawing, process specification, such as welding, heat-treating, and material specifications, operating instructions and manuals, maintenance manuals, structural repair manuals, the Type Certificate Data Sheet, and any other data the FAA decides is necessary to either operate maintain, or alter the aircraft. As an example if one were to place all documentation covering the FAA approval for a Cessna 150 aircraft on the floor, it would probably rise to over twenty feet high. To synthesize the data necessary for an IA to adequately accomplish an Annual or Progressive inspection on a Small Aircraft, the FAA issues a Type Certificate Data Sheet for every Type-certificated products, aircraft, engines, and propellers. These data sheets describe the minimum items that an IA must inspect on each product during Annual and Progressive inspections, along of course, with the list of items contained in FAR 43, Appendix D. The aircraft, to continue to be legal and in compliance with its FAA-issued airworthiness certificate as well as any policy of insurance, must always meet its Type Design or properly altered condition.

Now that we have learned about Type Design let us take a look at a real FAA Type Certificate Data Sheet. We will look at the Data Sheet A3SO that covers the Piper Cherokee Six for example.

A3SO Video Demo

Data Sheet A3SO-pdf covering the Piper Cherokee Six, is an FAA Type Certificate Data Sheet. This video explains how to read and better understand it.   

Data Sheet A3SO 

To begin, all Data Sheets are formatted in the same way. At the top you find the application statement, then the revision status, then the name and address of the current holder of the Type Certificate, and on down to each specific model in chronological order which has been approved. After the models are defined, you come to the Certification Basis such as CAR 3 or FAR 23, required equipment, data pertaining to all models, and it culminates in notes that are specified for particular models. The notes mentioned in the body of the Data Sheet paragraphs, and then spelled completely at the end, are of vital importance. For example, what is the Certifications Basis of Piper model PA32-260? Or, what engine can legally be installed in a Piper model PA32-260? Or, what propeller governor assembly can be installed on a Piper PA32-260? Lastly, what flight manual must be available in a Piper PA32-260 with the serial number 32-7300248? 

You should now see how important the Type Certificate Data Sheet is, and why it should be used as a checklist by an IA accomplishing an Annual or Progressive inspection. It is as necessary as the aircraft manufacturer’s checklist and FAR 43, Appendix D. How else can an IA verify that the aircraft meets its Type Design

End of Block Lesson One

Now you have finished Block One, and may review the remaining blocks in any order you would like. After reviewing all 8 blocks of learning, you are ready to take the quiz. I hope you have enjoyed, this lesson and have learned something that will help you and keep you out of trouble with the FAA.

Thank you for taking our Online Inspection Authorization Refresher Training Seminar!

bottom of page