A Type Certificate, is awarded by aviation regulating bodies to aerospace manufacturers after it has been established that the particular design of a civil aircraft, engine, or propeller has fulfilled the regulating bodies' current prevailing airworthiness requirements for the safe conduct of flights under all normally conceivable conditions (military types are usually exempted). Airworthiness is a term used to dictate whether an Aircraft is worthy of safe flight Aircraft produced under a type certified design are issued a Standard Airworthiness Certificate. A standard airworthiness certificate is a certificate issued by a state's civil aviation authority to permit the operation of the Aircraft.
Supplemental Type Certificate A Supplemental Type Certificate (STC) is a document issued by the Federal Aviation Administration approving a product (aircraft, engine, or propeller) modification. The STC defines the product design change, states how the modification affects the existing type design, and lists serial number effectivity. It also identifies the certification basis listing specific regulatory compliance for the design change. Information contained in the certification basis is helpful for those applicants proposing subsequent product modifications and evaluating certification basis compatibility with other STC modifications.
Initially, the applicant aerospace firm shall submit documents to the aviation regulating body (initially of the firms' home country) detailing how the proposed design would fulfill the airworthiness requirements. After investigations by the regulator, the final approval of such documents (after the required comments and amendments in order to fulfill the laws), becomes the basis of the certification. The firm follows it and draws a proposed timetable of actions required for certification tests.
An initial design sample known as a prototype is built. This refers to either the aircraft, the engines or the propeller, depending on the basis of the certification. For the purpose of illustration, the discussion shall be limited to the aircraft. Normally a few prototypes are built, each subject to different tests. The prototypes are first used for ground and system tests. One of the prototypes (known as the 'static airframe') is subject to destructive testing, i. e. the prototype is subject to stress beyond normal and abnormal operations until destruction. The test-results are compared with initial submitted calculations to establish the ultimate structural strength.
Other prototypes will undergo other systems tests until the satisfaction of the regulators. With all ground tests completed, prototypes are made read for flight tests. The flight tests are flown by specially approved flight test pilots who will fly the prototypes to establish the ultimate flight limits which should be within the airworthiness rules. If a long range airliner is tested, the flight tests may cover the whole world. ETOPS testing may require tests over oceans or remote areas.
In parallel with aircraft testing, the applicant firm also draws up maintenance program to support continuous airworthiness after approval of the design. The program is drawn with inputs from tests results and also from initial customers' engineering departments. The proposed maintenance program is submitted to the regulators for comment and approval.
After successful completion of ground and flight tests, along with an approved maintenance program, the prototype is approved,and the firm is granted the type certificate for the prototype (as understood that it should include all furnished equipment for its intended role). The legal term for the firm is now the "type certificate holder". Subsequently the prototype now serves as a template for aircraft production. Hence the aircraft rolling out of the factory should be identical to the prototype, and each given a serial number (a "series aircraft").
As the aircraft enters into service, it is subject to operational wear and tear which may cause performance degradations. The approved maintenance program serves to maintain the aircraft airworthiness. Users have to comply in order to maintain their aircraft's airworthiness certificate. The maintenance may be light or heavy (such as overhauls) as dictated by the schedules and tasks in the aircraft's maintenance program.
Sometimes during service the aircraft may encounter problems that may compromise the aircraft's safety, which are not anticipated or detected in prototype testing stages. The aircraft design is thus compromised. The regulators will now issue an airworthiness directives to the type certificate holder and to all owners globally. The directives normally consists of additional maintenance or design actions that are necessary to restore the type's airworthiness. Compliance is mandatory. Airworthiness directives may also be raised with changes of the local or global aviation rules and requirements, e. g. requirement to fit armored cockpit doors for all airliners post 9-11.
[The CAA issues an AD when an unsafe condition is found to exist in a product (aircraft, aircraft engine, propeller, or appliance) of a particular type design. AD's are used by the CAA to notify aircraft owners and operators of unsafe conditions and to require their correction. AD's prescribe the conditions and limitations,including inspection, repair, or alteration under which the product may continue to be operated.
With increasing in-service experience, the type certificate holder may find ways to improve the original design resulting in either lower maintenance costs or increased performance. These improvements (normally involving some alterations) are suggested through service bulletins to their customers as optional (and may be extra cost) items. The customers may exercise their discretion whether or not to incorporate the bulletins.
Often the basic design is enhanced further by the type certificate holder. Major changes beyond the authority of the service bulletins require amendments to the type certificate. For example, increasing (or decreasing) an aircraft's flight performance, range and load carrying capacity by altering its systems, fuselage, wings or engines resulting in a new variant may require re-certification. Again the basic process of type certifications is repeated (including maintenance programs). However, unaltered items from the basic design need not be retested. Normally, one or two of the original prototype fleet are remanufactured to the new proposed design. As long as the new design does not deviate too much from the original, static airframes do not need to be built. The resultant new prototypes are again subjected to flight tests.
Upon successful completion of the certification program, the original type certificate is amended to include the new variant (normally denoted by a new model number additional to the original type designation). Typical examples are; the Boeing 737NG (737-600, 737-700, 737-800 and 737-900) which replaced the 737 Classic family (737-100, 737-200, 737-300, 737-400 and 737-500) and the Airbus A340-500 and the A340-600 which is based on the Airbus A340-200 and the A340-300. The Boeing Company is a major Aerospace and defense corporation originally founded by William E Airbus SAS (ˈɛərbʌs in English, Airbus2ogg|/ɛʁbys/]] in French, and /ˈɛːɐbʊs/ in German) is an aircraft manufacturing
Any additions, omissions or alterations to the aircraft's certified layout, built-in equipment, airframe and engines, initiated by any party other than the type certificate holder, need an approved supplementary ("supplemental" in FAA terminology) type certificate, or STC. The scope of an STC can be extremely narrow or broad. It could include minor modifications to passenger cabin items or installed instruments. More substantial modifications may involve engine replacement, as in the Blackhawk modifications to Cessna Conquest and Beechcraft King Air turboprops, or a complete role change for the aircraft, such as converting a B-17 or Stearman into an agricultural aircraft. The Cessna 441 Conquest II was the first Turboprop designed by Cessna and was meant to fill the gap between their jets and Piston -engined This article is about 90 and 100 Series King Airs For 200 and 300 Series King Airs see the Beechcraft Super King Air article A turboprop engine is a type of aircraft powerplant that uses a Gas turbine engine to drive a Propeller. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout STCs are applied due to either the type certificate holder's refusal (frequently due to economics) or its inability to meet some owners' requirements. STCs are frequently raised for out-of-production aircraft types conversions to fit new roles. Before STCs are issued, procedures similar to type certificate changes for new variants are followed, likely including thorough flight tests. STCs belong to the STC holder and are generally more restrictive than type certificate changes.
The type certificate holder keeps the type certificate valid by continuously following airworthiness directives, issuing service bulletins and as well as providing spares and technical support to keep the aircraft current with the prevailing rules. This is true even if the production of the type has stopped. This is what is meant by supporting the type and in this manner many out-of-production aircraft continue useful lives. Typical examples are old Boeings, Airbuses, McDonnell Douglasses, Lockheeds, Fokkers, Dorniers and many others. McDonnell Douglas was a major American Aerospace manufacturer and Defense contractor, producing a number of famous commercial and military aircraft The Lockheed Corporation (originally Loughead Aircraft Manufacturing Company was an American aerospace company founded in 1912 which merged with Martin Marietta Fokker was a Dutch Aircraft manufacturer named after its founder Anthony Fokker. STCs are also bound by the same rules. When the holder decides to stop supporting the aircraft type (due to many reasons mainly economic), the type certificate is returned to the regulators and the remaining aircraft fleet permanently grounded. In this manner the whole Concorde fleet was finally grounded when Airbus SAS surrendered its type certificate. WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Airbus SAS (ˈɛərbʌs in English, Airbus2ogg|/ɛʁbys/]] in French, and /ˈɛːɐbʊs/ in German) is an aircraft manufacturing