Every day within the United States there are over 44,000 flights that carry over 2.7 million passengers. Given these large numbers, the airline industry is remarkably efficient, with airports and operators continuing to improve their turnaround times for planes while still maintaining all mandated safety protocol. The U.S. Federal Aviation Administration (FAA), along with its numerous partners, coordinates with airline operators to ensure that all aircraft which plan to fly the American skies are safe and ready to fly.
Predictably, this is a complex environment to navigate with many different models of aircraft in the sky at any given time being operated by numerous carriers. There are also many foreign flights entering U.S. airspace each day to land and take off across the country. A critical component of ensuring flight safety is the FAA’s Aircraft Certification Service, abbreviated as AIR. This group consists of more than 1,300 air industry professionals such as engineers, inspectors, pilots, and scientists that oversee the airworthiness certification process for all forms of civil aviation equipment. While AIR oversees an array of different aircraft, it deals mostly with commercial planes and helicopters.
Screenshot via FAA
AIR aside, the United States is far from the only country with an association that grants airworthiness certifications based on strict criteria. The effort is also international, with coordination between the FAA, International Civil Aviation Organization (ICAO), and other aviation authorities to maintain safe travel for all flights around the world. As airline manufacturers continue to innovate and release new, more technologically advanced versions of their aircraft, there’s a clear need to validate these planes for safe travel in addition to maintaining existing fleets. As such, there are a number of regulations that govern how airworthiness certifications are granted and what must be done to maintain them in good standing.
In this guide we will cover the following airworthiness-related topics:
In order for an aircraft to be considered capable of safe flight, referred to as ‘airworthiness,’ it must meet a couple of important criteria outlined by the FAA in FAR Part 21.183. Each aircraft that is manufactured is created based on a Type Certificate (TC) that includes the specifications, drawings, and data upon which it was designed. Additionally, an aircraft that receives field approved alterations can receive additional documentation such as a Supplemental Type Certificate (STC). One essential measure of airworthiness is that the aircraft conforms to all aspects of the TC, STC, and any approved alteration documentation. In the simplest terms, this means that the aircraft still retains all the original characteristics upon which it was designed.
The second determination of airworthiness has to do with the state of the aircraft. The aircraft must be in a well-maintained state with respect to any leaks, interior or exterior wear, tire condition, and much more. If the aircraft passes all maintenance checks and is clear of any operational issues otherwise deemed unsafe, it is considered airworthy and issued a standard certification. In some cases, an aircraft that does not meet some criteria from the above but is still deemed capable of flight can be issued a special airworthiness certification and be allowed to fly, sometimes with certain operating limitations.
Aircraft owners, operators, and manufacturers in the industry strive for continued airworthiness to keep their planes running and on schedule. An aircraft can sustain its airworthiness by meeting the two criteria:
The FAA maintains a database of Type Certificate Data Sheets (TCDS) which contain the make and model information for any aircraft, engine, or propeller flown in the United States. Within each TCDS is a formal description for each product that includes published limits for specifications such as airspeed, weight, and thrust. The TCDS documents are updated with any changes and the FAA tracks the revision history for each record. It is important to note that the electronic database on the FAA website is current from 1999. Historical records are held in local databases but may not be visible online.
Screenshot via ICAO
The Aircraft Certification Service of the FAA handles the airworthiness certification of nearly all U.S. civil aviation hardware including planes and parts. These members also collaborate with the International Civil Aviation Organization (ICAO) and other authorities to coordinate flight safety activities internationally.
As part of their program, the FAA designates certain qualified individuals or organizations the authority to perform select tasks related to airworthiness certification and other responsibilities. These parties are referred to as Organization Designation Authorizations (ODAs). Utilizing these resources allows the FAA to expand its technical resources while maintaining the standards they control.
The FAA has always had an active role in the certification of airworthiness. Because of this, it has been a longstanding rule that flight owners and operators are not allowed to process their own certifications. Each inspection must be done by the FAA or a designated ODA. The FAA also controls the certifications for any new proposed aircraft features or technology through the Flight Standardization Board (FSB). The airworthiness certification workflow is kept consistent among all individuals or organizations that perform the function.
The primary purpose of airworthiness certification to ensure that aircraft are ready to fly and good operational condition prior to beginning routine flights. As a result, requests for certification are often initiated when a new or used aircraft has changed owners or is planning to become operational again after being grounded for some time. The most common situations requesting an airworthiness certificate to be issued are:
The process of certification is robust and well established. During certification, the FAA or ODA will perform a review of any proposed design changes to the aircraft and the associated data that proves these changes are suitable for safe flight and comply with FAA regulations. Flight and ground tests are also performed to establish that the equipment is fully operational and performing to standards. The maintenance procedures and schedule are then reviewed to confirm whether or not the aircraft will be properly serviced and ready for flight. Upon successfully meeting all criteria, the FAA will either a standard airworthiness certificate (Form 8100-2) or a special airworthiness certificate (Form 8130-7) depending upon the condition and unique requirements of the aircraft.
In the case of an imported aircraft, the FAA may coordinate with international civil aviation authorities to confirm approval of airworthiness prior to certification. In all situations, the local FAA servicing offices are an important contact point for any questions regarding airworthiness certifications.
Receiving an airworthiness certificate is an important initial step in getting an aircraft into the air and operational. Upon receipt of the certificate, the owner or operator must display the certificate in the aircraft so that it is visible to all occupants. The certificate is valid unless it is surrendered, suspended, revoked, or passes any termination date set by the FAA. It is also important to note that airworthiness certificates can be transferred to another party upon sale (14 CFR 21.179) if all other conditions and requirements are met and maintained.
The owner and operator of an aircraft also have a number of important responsibilities to keep their airworthiness certificate in good standing. According to 14 CFR parts 21, 43, 91, the condition of the aircraft must be safe for operation and all maintenance and alterations properly performed. Any required inspections must be completed according to protocol, and the certificate must be made available to the FAA for inspection at any time.
On occasion, the FAA will issue Airworthiness Directives (ADs) which are legally enforceable rules meant to correct an unsafe condition found in an aircraft, engine, propeller, or appliance. The rules that dictate these directives are found in 14 CRF part 39, and the FAA maintains a current listing of all active ADs on their website. All aircraft owners and operators must comply with any ADs that impact their aircraft and follow the required actions.
Advisory Circulars (ACs) are another form of notifications that provide guidance on certification, compliance with regulations, recommendations, and other information. For instance, AC 43-213A provides parts marking identification guidance, while AC 45-2E offers non-mandatory guidance on identification and registration marking. AC 45-4 provides information on “identification, marking, and placarding of aircraft issued special airworthiness certificates in the light-sport category (S-LSA) and aircraft issued experimental certificates for the purpose of operating light-sport aircraft (E-LSA),” including requirements for aircraft identification plates, displaying nationality and registration marks, and displaying placards on aircraft in these categories.
Another series of notifications the FAA reviews are Service Bulletins (SBs) that are sent from aircraft manufacturers to the operators notifying them of a safety-related equipment improvement. In many cases, the FAA will issue an associated AD in reference to an SB which will make any outlined changes a requirement. Some SBs are released as alert bulletins, meaning that they require immediate follow-up. Alert bulletins and any SB referenced in an AD can directly impact the airworthiness certification of an aircraft and must be complied with, while any other general SBs are usually considered optional.
The ultimate responsibility for determining the airworthiness of a civil aircraft for each flight rests with the pilot. They must perform the necessary due diligence and consider all factors both pre-flight and during flight to determine if at any time the aircraft is un-airworthy due to an issue. In those situations, the flight should be stopped and proper safety arrangements made. Failure to comply with any of these requirements would require the owner or operator to forfeit the airworthiness certificate to the FAA.
The grounding of the Boeing 737-MAX in March 2019 after the crash of Ethiopian Airlines Flight 302 has brought national attention to airworthiness certification and how the FAA and coordinating organizations manage the situation. The fleet is still grounded as of September 2019, and the Joint Authorities Technical Review (JATR) Panel that is overseeing the review process is preparing to release its findings shortly.
Given the complexity of the situation, it makes an interesting study in airworthiness. After the initial crash of Lion Air Flight 610 on October 29, 2018, the FAA released AD 2018-23-51 with guidance related to the flight controls of the Boeing system. Later, in March of 2019 when there were suspected similarities between the Lion Air and Ethiopian Airlines incidents, the FAA issued a Continued Airworthiness Notification outlining its investigation. A few days later, this was followed by an Emergency Order directing the grounding of the 737-MAX pending satisfactory resolution of the investigation.
With the investigation is ongoing and focused on the Maneuvering Characteristics Augmentation System (MCAS), it remains to be seen exactly how the investigation will conclude and when airworthiness can be reinstated. There are also ongoing communications between the FAA and other international entities, such as the European Union Aviation Safety Agency (EASA) as to what will constitute a satisfactory resolution. It places clear pressure on all parties involved to maintain coordination during the extensive review of the design, certification, regulations, and training, related to the 737 MAX. It is a clear reminder of the need for robust flight safety protocols and the resources that can be coordinated to solve identified issues.
Airworthiness certification has broad influence in the aviation industry and plays a major part in ensuring flight safety. As you can see from this guide, it represents a critical checkpoint in the ongoing inspection and maintenance of aircraft. Achieving airworthiness certification requires close coordination between the FAA, its technical partners, and aircraft operators. Understanding the important aspects of this process will help ensure the future airworthiness for aircraft in the future.
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