Manifold Pressure and More
A high MP low RPM setting uses less fuel than a low MP high RPM setting for the same output power. The energy required to overcome pumping losses makes the difference. The further open the throttle the less work the engine has to do moving the pistons against atmospheric pressure on the intake stroke.

Power in an engine is the product of Manifold pressure, displacement, and RPM. We can vary Manifold pressure and RPM, but displacement is fixed. Performance is determined by available power. The air volume and density used by the engine is determined by RPM and displacement. The lower the MP the lower the air density in the intake manifold, and the less air is moved at any given RPM. RPM has a greater effect on the amount of air than does MP. A higher RPM for any given power will result in more fuel burned for that power.

Since POWER is proportional to the product of MP and RPM you can get the same power at many different combinations of the two. You can increase MP and decrease RPM and keep the power the same. The lowest fuel consumption for any given power output would be at the combination that gives the highest MP and the lowest RPM. An increase in MP and a lower RPM will increase the pressure and temperature inside the engine. You will eventually reach the pressure point where detonation occurs. You will ruin the engine if it continues this operation.

The POH gives operational figures that preclude detonation. The figures that have highest MP/lowest RPM give the lowest fuel burn for the power setting. Higher altitudes will reduce the available MP. As you climb a higher RPM will be required to reach or maintain the power percentage desired. At 7500 feet and full throttle will give you 75% power for a normally aspirated engine.

A&P Inspection Authorization
--Is A & P who is responsible in assuring of highest levels of trust, responsibility and values of the A & Ps.
--Inspection Authorization under FARs..
--65.91 Applicant must meet requirements and is actively engaged in aircraft maintenance (35 hours a week with a work place phone number)
--65.92. Every March 31 IA must be renewed.
--65.93 Must perform one annual inspection for every 90 days certified, two major repairs or alterations, a progressive inspection , taken eight-hour renewal meeting, or oral quiz by FAA inspector
--65.95 AI can perform annual inspections, supervise progressive inspections. inspect major repairs, inspect major alterations. notify FSDO of any change in AI location.

AI Authorization
The Federal Aviation Administration, reposing special trust and confidence in your integrity, diligence, and discretion and finding that he or she has the necessary knowledge, skill, experience, and impartial judgment, to merit special public responsibility the FAA, now grants/renews your Inspection Authorization.
History
-- The AMEs were the first designees
--Pilot designees appeared in 1941.
--FAA created in 1958 along with annual inspection requirement.

About the Annual Inspection
--Get several references for any AI before you get involved.
--Having every annual inspection done at the same place may not be wise.
--Owner should pre-arrange right to participate and not pay AI to watch work being done.
--FAR Part 43 lists inspection items required.
--The annual is an inspection only by a mechanic with an inspection authorization using a checklist.
--Inspection is complete when aircraft logbook entries are completed by the AI.
--AI's opinion cannot be appealed only complied with.
--AI can be expected to document every decision by means of specification and documentation.
--All items making aircraft unairworthy are listed as a part of the inspection logbook entry.
--It is an expensive mistake to stop the inspection to fix a discrepancy. Complete inspection then repair.
--Any AD's must be complied with and logged properly.
--Owner is responsible for compliance with AD's as to when, where and how compliance was performed.
--Repair requires a certified mechanic. The AI and the A&P need not be the same person.
--A&P must make logbook entry certifying aircraft safe for ferry permit flight …or
--A&P must make logbook entry certifying all of AI's entries have been complied with and aircraft airworthy.
--Final responsibility of airworthiness lies with owner. Airworthiness is determined before each flight.
--Aircraft must meet specifications of type certificate in equipment and tolerances of components.
--AC 43-13 gives approved repair procedures

Annual Inspection by Checklist Phases
--Paperwork and ADs
--Past records reviewed
--Compliance with all ADs confirmed on plane and in logs
--New and recurrent ADs added to checklist
--Class I appliances (major components) type certificate data sheet (TCDS), STC and alterations comply.
--Run-up and systems
--Washing and disassembly
--Inspection
--Table of limits and specifications to determine if serviceable
--Preventative maintenance
--Owner can do preventative maintenance if IA inspects work
--Lubrication and adjustments are part of preventative maintenance
--Reassembly
--Owner can disassemble and assemble as long as AI inspects procedure
--Post-annual run-up and systems check
--Logbook entries
--When inspection is complete unairworthy items must be corrected before airplane is returned to service
--Research inspection items to confirm tolerances specified
--AI must list all discrepancies
--A & P must complete log for every discrepancy satisfied.

PART 145 Repair Stations
--Created in 1939
--Regulations codified in 1962
--5000 repair stations exist
--New 2001 rule is 151 pages long at http://
--Effective date is April6, 2003
--Contains new terminology and definitions
--Requires quality control of work and parts
--Requires stable location
--No change in certification of repairmen or operating specifications

FAA Approved Interior
--Only FAA certified items and materials can be used on or in an aircraft.
--Only original or certified at meeting type requirements materials can be used.
--Any installation must be capable of being inspected and maintained.
--A minor change uses acceptable recorded materials and parts such as originally used.
--Aircraft materials must be flash resistant and flame resistant by certified test.
--Approved FAA Repair Stations can perform the Part 23 burn test and recorded in logbooks.
--Keep all records, invoices and samples of materials and an additional set separately
--A major change uses material or parts that require creation of data for acceptance.
--Approved data requires check by rated Designated Engineering Representative, an STC or field approval.
--Any STC includes instructions for maintenance and Instructions for Maintaining Continued Airworthiness  (IMCA)
--The IMCA are put into the logbooks along with a replacement parts list.
--Interior installation and maintenance requirements are the most frequently overlooked airworthiness requirement.

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