Names and architecture
In basic system architecture these displays are similar to the EFIS (electronic flight instrument system): the same chain the last lesson drew, data into a symbol generator, the generator's picture onto display units, with source switching behind it. What varies wildly is the naming, and the syllabus asks for the list:
multifunction display unit (MFDU) — the generic name;
engine indication and crew alerting system (EICAS) — the Boeing family's name;
electronic centralised aircraft monitor (ECAM) — the Airbus monitoring system;
engine and warning display (EWD) — the upper of ECAM's two screens;
systems display (S/D) — the systems page beneath it.
Five names, one idea: engine parameters, crew warnings, aircraft systems and procedures, on screens instead of dials and paper.
The computer's limits
Before trusting the drills these screens propose, understand what the machine behind them can and cannot know. The computer has a limited ability to assess a situation: it uses the exceedance of certain thresholds to trigger the main and subsequent events and the programmed actions. A parameter crosses a line, an alert fires, a checklist follows: that is the whole mechanism. The computer does not know why the parameter crossed the line, and that is why awareness of the consequences of the actions commanded by the automatic checklist is required: the checklist was written for the threshold, not for the cause, and the crew is the only party in the loop that can tell the difference.
Flying the electronic checklist
The appropriate procedure for an on-screen checklist after a failure has four disciplines, listed for the exam:
confirm the failure with the other flight crew member before performing any action — no drill is flown against a misread alert;
seek confirmation before manipulating any guarded switch or a thrust lever — the irreversible controls demand a second pair of eyes;
follow the checklist slowly and methodically — the screen's patience is infinite even when the crew's is not;
assess the possible implications of making certain selections — the syllabus's own example being opening the fuel cross-feed when there is a fuel leak, even though the electronic checklist may ask for the action.
The electronic flight bag
The electronic flight bag (EFB) replaces the paper the flight bag used to carry: charts, manuals, performance and loading calculations, on a screen. The typical equipment:
Certifying the EFB
Certification splits twice. The 'class' certification covers the hardware:
a portable EFB is a portable electronic device (PED) that can be used inside or outside the aircraft, is not part of the certified aircraft configuration, and needs no tools to remove it from its flight-deck cradle if one exists;
an installed EFB is an aircraft part, covered by the aircraft's airworthiness approval, and therefore a minimum equipment list (MEL) item when it fails.
The 'type' certification covers the software:
type A applications are those whose misuse or malfunction has no adverse effect on flight safety;
type B applications are those for which an evaluation of the hazards presented by misuse or malfunction is required.
A static copy of a manual on one side, a performance calculator whose wrong answer reaches the runway on the other.
When the EFB fails
In a fully electronic flight-deck environment the EFB is not a convenience, it is the library, and its malfunction has implications the syllabus lists: the mass and balance calculations, the performance calculations, the access to charts and the access to manuals can all be lost at once, with no paper behind them. A dead tablet before departure is a dispatch question, not an annoyance.
The head-up display
The head-up display (HUD), met briefly in the autoland lesson's hybrid landing systems, puts the flying picture between the pilot's eyes and the world. The components of a typical installation:
the HUD projector and its stowable combiner, the angled glass that folds away when not in use.
the HUD controls, such as declutter and dimmer.
the HUD computer that builds the symbology.
The reasons and benefits:
increased situational awareness — the primary flight information no longer requires looking inside;
lower minima for both departure and landing;
improved accuracy of flying — and with it a reduced susceptibility to entering an aircraft upset, the eyes never leaving the flight path while the data rides on the glass.