I agree, but the thread title is “everything installed” which is perhaps not what most would expect. We’ve had loads of posts saying you can fly (day VFR) without such and such an instrument. It’s probably not easy to find a clear reference on what equipment is mandatory. Some take the position is that all equipment used for the original certification (excluding options, like the fire extinguisher in a TB) must be present and working. In most light GA cases there is no MEL.
achimha wrote:
What if the MEL requires working low fuel lights?
Then you need a changed MEL after the STC.
With unserviceabilities, a reference is often made to the “original design specification”. If the equipment came installed on the original design, i.e. the type certificate was issued on the basis of it, without this equipment serviceable the plane is unairworthy. Unless there is approved documentation stating it is a permissible unserviceability. (An MEL fulfills that purpose, but normally private owners wouldn’t have a MEL? There are also the radio and navigation equipment requirements in the AIP, which may for example state that only 1 radio is required for VFR flight.)
Perhaps slightly off-topic. I don’t know about other aircraft, but my N-reg C172 AFM has an equipment list in section 6, Weight&Balance/Equipment List.
This is a table of all equipment available for installation on a new aircraft from Cessna (1979-era). The list is 10 pages long and grouped into sections A-J (powerplant, landing gear, electrical, instruments, cabin, placards/manuals, aux eqpt, avionics, special options). Each item in the list has a suffix R (required for FAA cert), S (std equipment), O (optional replacing req’d or std), or A (optional addition to req’d or std). After that is the factory weight & balance listing the items from the table applicable to the specific aircraft (itemized or grouped).
Subject to FAA regs regarding specific equipment requirements for various flight situations, anything in the above table with -R suffix (and evtl -O when replacing an -R part) is required for airworthiness/flight. One could consider this the manufacturer’s MEL.
AFAIK, any other equipment can be made and/or placarded inop, although certain additional option packages can’t really be placarded in this way (e.g. floatplane equipment kit).
