Chapter 2
Aerodynamics, Aircraft Assembly, & Rigging
Before approving the aircraft for return to service after the annual or 100-hour inspection, 14 CFR states that the engine must be run to determine satisfactory performance in accordance with the manufacturers recommendations. The run must include:
- Power output (static and idle rpm)
- Magnetos (for drop and switch ground)
- Fuel and oil pressure
- Cylinder and oil temperature
After the run, the engine is inspected for fluid leaks and the oil level is checked a final time before close up of the cowling.
With the aircraft inspection completed, all inspections plates, access doors, fairing and cowling that were removed, must be reinstalled. It is a good practice to visually check inside the inspection areas for tools, shop rags, etc., prior to close up. Using the checklist and discrepancy list to review areas that were repaired will help ensure the aircraft is properly returned to service.
Upon completion of the inspection, the records for each airframe, engine, propeller, and appliance must be signed off. The record entry in accordance with 14 CFR part 43, section 43.11, must include the following information:
- The type inspection and a brief description of the extent of the inspection.
- The date of the inspection and aircraft total time in service.
- The signature, the certificate number, and kind of certificate held by the person approving or disapproving for return to service the aircraft, airframe, aircraft engine, propeller, appliance, component part, or portions thereof.
- For the annual and 100-hour inspection, if the aircraft is found to be airworthy and approved for return to service, enter the following statement: “I certify that this aircraft has been inspected in accordance with a (insert type) inspection and was determined to be in airworthy condition.”
- If the aircraft is not approved for return to service because of necessary maintenance, noncompliance with applicable specifications, airworthiness directives, or other approved data, enter the following statement: “I certify that this aircraft has been inspected in accordance with a (insert type) inspection and a list of discrepancies and unairworthy items has been provided to the aircraft owner or operator.”
If the owner or operator did not want the discrepancies and/or unairworthy items repaired at the location where the inspection was accomplished, they may have the option of flying the aircraft to another location with a Special Flight Permit (Ferry Permit). An application for a Special Flight Permit can be made at the local FAA FSDO.
Other Aircraft Inspection & Maintenance Programs
Aircraft operating under 14 CFR part 135, Commuter and On Demand, have additional rules for maintenance that must be followed beyond those in 14 CFR parts 43 and 91.
14 CFR part 135, section 135.411 describes the applicable sections for maintaining aircraft that are type certificated for a passenger seating configuration, excluding any pilot seat, of nine seats or less, and which sections are applicable to maintaining aircraft with 10 or more passenger seats. The following sections apply to aircraft with nine seats or less:
- Section 135.415—requires each certificate holder to submit a Service Difficulty Report, whenever they have an occurrence, failure, malfunction, or defect in an aircraft concerning the list detailed in this section of the regulation.
- Section 135.417—requires each certificate holder to mail or deliver a Mechanical Interruption Report, for occurrences in multi-engine aircraft, concerning unscheduled flight interruptions, and the number of propeller featherings in flight, as detailed in this section of the regulation.
- Section 135.421—requires each certificate holder to comply with the manufacturer’s recommended maintenance programs, or a program approved by the FAA for each aircraft, engine, propeller, rotor, and each item of emergency required by 14 CFR part
- This section also details requirements for single-engine IFR passenger-carrying operations.
- Section 135.422—this section applies to multi-engine airplanes and details requirements for Aging Airplane Inspections and Records review. It excludes airplanes in schedule operations between any point within the State of Alaska.
Any certificated operator using aircraft with ten or more passenger seats must have the required organization and maintenance programs, along with competent and knowledgeable people to ensure a safe operation. Title 14 of the CFR, sections 135.423 through 135.443 are numerous and complex, and compliance is required; however, they are not summarized in this handbook. It is the responsibility of the certificated operator to know and comply with these and all other applicable equirements of 14 CFR, and they should contact their local FAA FSDO for further guidance.
The approved aircraft inspection program (AAIP) is an FAA-approved inspection program for aircraft of nine or less passenger seats operated under 14 CFR part 135. The AAIP is an operator developed program tailored to their particular needs to satisfy aircraft inspection requirements. This program allows operators to develop procedures and time intervals for the accomplishment of inspection tasks in accordance with the needs of the aircraft, rather than repeat all the tasks at each 100-hour interval.
The operator is responsible for the AAIP. The program must encompass the total aircraft; including all avionics equipment, emergency equipment, cargo provisions, etc. FAA Advisory Circular 135-10 (as revised) provides detailed guidance to develop an approved aircraft inspection program. The following is a summary, in part, of elements that the program should include:
- A schedule of individual tasks (inspections) or groups of tasks, as well as the frequency for performing those tasks.
- Work forms designating those tasks with a signoff provision for each. The forms may be developed by the operator or obtained from another source.
- Instructions for accomplishing each task. These tasks must satisfy 14 CFR part 43, section 43.13(a), regarding methods, techniques, practices, tools, and equipment. The instructions should include adequate information in a form suitable for use by the person performing the work.
- Provisions for operator-developed revisions to referenced instructions should be incorporated in the operator’s manual.
- A system for recording discrepancies and their correction.
- A means for accounting for work forms upon completion of the inspection. These forms are used to satisfy the requirements of 14 CFR part 91, section 91.417, so they must be complete, legible, and identifiable as to the aircraft and specific inspection to which they relate.
- Accommodation for variations in equipment and configurations between aircraft in the fleet.
- Provisions for transferring an aircraft from another program to the AAIP.
The development of the AAIP may come from one of the following sources:
- An adoption of an aircraft manufacturer’s inspection in its entirety. However, many aircraft manufacturers’ programs do not encompass avionics, emergency equipment, appliances, and related installations that must be incorporated into the AAIP. The inspection of these items and systems will require additions to the program to ensure they comply with the air carrier’s operation specifications and as applicable to 14 CFR.
- A modified manufacturer’s program. The operator may modify a manufacturer’s inspection program to suit its needs. Modifications should be clearly identified and provide an equivalent level of safety to those in the manufacturer’s approved program.
- An operator-developed program. This type of program is developed in its entirety by the operator. It should include methods, techniques, practices, and standards necessary for proper accomplishment of the program.
- An existing progressive inspection program (14 CFR part 91.409(d)) may be used as a basis for the development of an AAIP.
As part of this inspection program, the FAA strongly recommends that a Corrosion Protection Control Program and a supplemental structural inspection type program be included.