Passenger Systems — Part 1

Passenger Service & Entertainment Systems Explained:
Besides the standard “fascination with aviation” and a geek-like interest in electronics, what truly lured me into the airline business, was the travel benefits. Sipping Mai Tais and chatting up flight attendants at the Honolulu Interline Club, high atop the Reef Hotel on Waikiki Beach, was a pretty cool perk for a young, single guy. Being single also meant that my parents were able to enjoy the benefits of nearly free interline travel.

Decades later, my dad (now almost 90) STILL brags about flying first class on a British Airways 747, and being served rack of lamb, carved to order at his oversized upper deck seat. Although this is a far cry from the bag of chips and stale sandwich that must be ordered and paid for in advance on many of today’s flights, we must nonetheless never lose sight of the fact that the primary function of an airline is to move people from place to place around the globe, and that we must provide them with a certain level of comfort and accommodation.

As maintainers, we tend to focus on “the machine” that is, the aircraft, rather than the “living space” that is the passenger cabin. Avionics types tend to focus on the cramped little room at the front of the machine, with its instruments, radios and controls. Mechanics tend to focus on engines, flight controls and undercarriages.

(A puzzled RAF engineer once asked me: “Why do you Yanks call it a ‘landing gear’? Don’t you use it for taxi and take off as well?” He has a point, so I’ve called it an undercarriage ever since.)

We tend to think of the passenger service items as “luxury add-ons” rather than priority items. When introducing my students to passenger service systems, I always present them with the following scenario: “If an airplane arrives at your base with two snags: 1. the autopilot will not stay engaged, and 2. the passenger entertainment system in the first class cabin is inoperative, and you only have time to fix one before the aircraft departs for Sydney Australia, which would you fix?” Invariably, most of them opt for fixing the autopilot snag. It doesn’t occur to them that the passengers will never know that the pilots had to hand-fly the aircraft, but a passenger paying over $10,000 for a one-way ticket to Australia who can’t even watch an inflight movie will NEVER fly on your airline again! A commuter aircraft doing a 7 a.m. business fight of the “Toronto/Montreal” or “New York/Washington” ilk MUST have serviceable coffee-makers to provide the bleary-eyed business travelers with their morning java. Failure to do so would, once again, mean a loss of future custom from these passengers.

It is therefore not only a good maintenance practice, but also a good business practice to ensure the integrity and operation of all customer comfort related aspects of the aircraft. In the competitive airline market of today, we must realize the importance of winning and securing customer loyalty. In Canada, we face the allure of cross-border airline shopping where discount flights aboard US carriers are often a short drive away. Failure to address passenger service issues could easily cost an airline the loss of a valuable patron. What then can we, as maintainers, do towards this end?

The first step, I believe, is the realization that the Cabin Logbook, usually filled out by flight attendants, deserves as much of our attention as the Cockpit Logbook filled out by pilots. Notwithstanding NO GO items, snags associated with passenger convenience and comfort should be given the appropriate amount of time and attention they deserve. Replacing burned out reading lights may seem like a trivial and tedious task, and is often deferred until the next A Check, but consider how many bored passengers will become annoyed at being unable to pass the time on a long flight by reading a newspaper, magazine or book. Between the time that the snag occurs and when the next A Check rolls around, failing to complete that two-minute task could result in the loss of several future passengers.

While rack of lamb carved at your seat may be a thing of the distant past, most long-distance flights do offer hot meals and hot drinks. Having a technician check the integrity and operation of the galley fixtures could prevent a future inflight failure or departure delay. Coffee-maker hoses should be checked to ensure that there is no pinching, chaffing or kinks. Oven power receptacles can be checked for correct voltages and ground connections as well as signs of overheating and misalignment. Switch and timer functions should be verified to confirm that the appropriate power is delivered at the appropriate time.
Oven, coffee-maker, and hot cup circuit breakers are pulled and reset far more often than most aircraft C/Bs
and thus tend to wear out more quickly. A check of the tension required to open these breakers could signal the need
for replacement before an actual failure occurs.

It is noteworthy also that galley accidents are the number one cause of flight attendant injuries. The risk can be reduced if we ensure that all appropriate lighting is operational, non-slip surfaces are intact, and all locks and latches are fully functional.
Shifting our focus from the galley to the passenger seat, it’s fair to say that passenger entertainment systems have been constantly evolving since the introduction of the “Inflight Movie” in the 1960s. From the early days of in-flight movies, employing monstrous film projectors and even more monstrous reels of celluloid film, to the current individual seat video, with choice of live satellite feed TV, internet connections and an array of feature films, nothing passes the time on a long, boring flight like a little audio-video entertainment.

What most passengers don’t know, however, is that the same system that allows them to listen to so many different channels of audio on the headset plugged into their arm rest also controls their reading light, call button, oxygen mask, and in some cases, even toilet flush motors in the lavs at the rear of
the cabin!

To find out how all these items tie together and how we can better maintain them, be sure to read  “Passenger Accommodation: Explained Part 2” in the next issue of AMU.

Q: What procedures should be followed when checking an aircraft’s galley oven receptacles?

Answer to last issue’s question:

Q: How do recombinant gas, relief valve lead acid batteries prevent the spillage of electrolyte?

A: The electrolyte is absorbed by the glass mats, and the case is sealed