If airlines and aircraft manufacturers were to characterise just one physical property of aeroplanes as the ultimate enemy, it would be weight. Weight increases drag and fuel consumption and reduces payload, so carriers and builders fight all the time to reduce it without sacrificing friendly properties such as strength, durability and efficiency.
Today, however, airlines are choosing seats which weigh 10-15kg more than they need to for structural reasons, without being more comfortable, and which have no underseat bag-stowage space. They are also sacrificing space which could otherwise be used for wardrobes for passengers' coats and jackets, or for accommodating more carry-on baggage. The god to which they are making these sacrifices of weight and space is sophisticated inflight entertainment (IFE). The price of passengers' entertainment is the cost of IFE installation and maintenance, the extra fuel for keeping it airborne, and for the payload lost - an IFE system can weigh at least 680kg. How long, therefore, before the no-frills scheduled-operator phenomenon comes to long-haul routes?
Seat-design emphasis
Rapidly expanding UK-based Britax Rumbold, one of the world's largest prestige passenger-seat manufacturers, admits that IFE has shifted the emphasis in seat design away from pure weight, comfort and good looks. Technical director John Higgins says: "Seats have become electronics racks." This particularly applies to Rumbold, because the company specialises in business- and first-class seats, which contain the most complex IFE/communications systems.
IFE equipment adds to the seat-frame and floor-anchorage weight - and ultimately to that of the floor. This effect has been exaggerated by the new, fully implemented European and US requirement that seats in new-design aircraft should be able to withstand 16g acceleration in dynamic testing. The old rule was 9g static loading. This ruling so far affects only the Airbus A330/A340 series and the Boeing 777; other types are still subject to the earlier, lower standards under "grandfather" rights.
Static testing consists of applying the 9g loads using a rig with hydraulic rams. Dynamic testing incorporates the shock-loading effect by requiring that the seat on the rig (attached to its floor-mountings) is propelled along rails, then subjected to 16g deceleration. The US Federal Aviation Administration, however, has seriously worried the US airline industry by giving notice that it is considering applying the 16g requirement retrospectively to the entire US fleet. If the FAA were to push through the retroactive 16g ruling, the Boeing 747 and 767 would be particularly vulnerable, says Rumbold, because their floor-strengths are relatively low.
Those apprehensions are heightened by US-based IFE- and furniture-manufacturer BE Aerospace (BEA), which confirms its belief that the FAA legislation is definitely on the way by predicting a phased implementation during the next four years.
Higgins says that Rumbold has, from the engineering and the safety-regulation points of view, become an IFE "systems integrator", in the sense that each seat is now a multi-unit, multi-mode IFE system. The underseat equipment for a full audio-visual system with a telephone will normally include:
A signal decoder; two communications boxes for the passenger telephone; a control/connector box for a reading light; a power-transformer box for the personal-computer power-supply point (the crew has to be able to switch this off from the cockpit); a personal video-player (for those airlines which offer an on-board video library) wiring looms to the seats and within them.If aisle-path lighting is wanted on the side of the seats, as it often is because airlines have found that floor-level-lighting is too vulnerable to damage, that means another in-seat box, more cables and a standby battery.
Heat dissipation
The equipment-stowage area needs ventilation to dissipate heat from units such as transformers and video players, but also shrouding which protects the equipment from damage, including liquid spillage. The shrouding has to look smart, and provide easy access for maintenance, but pose no danger from detachment in an accident.
Electrically controlled first-class seats with a full IFE/communications suite need full shrouding of the underseat space, Higgins says, pointing out that first-class seat-pitches are so generous that this does not create a problem for the passenger. With business-class seats and bag stowage, however, seat pitches are usually such that underseat foot-room is necessary.
Screens and handsets have to be stowed away, and manufacturers have to prove that they will not emerge to cause damage or obstruction during the deceleration tests. Safety in accidents is not the only strength consideration, however. Video-screen arms, for example, have to be able to take a 120kg "abuse load", which means that they must not be easy to damage by mistake. Passenger-restraint systems have to be considered, together with matters such as passenger head-strike on a screen or other parts of the IFE equipment. This means either that padding has to be built-in, or that the system has to have a set break-away limit. Telephone cords must be designed so that they cannot be passed across an aisle, creating a trip hazard.
Finally, there has to be connection to the central cabin IFE-control station, and power-supply to the in-seat equipment. All this creates weight, not to mention power demand on the aircraft's engine-driven generators. The wiring "raceways", says Higgins, are now complex where they used to be simple. Because seat layout has to be either customer tailored or completely flexible, the option of underfloor wiring is too cumbersome, so the raceways have to be in under-carpet conduits, which is particularly problematic when they have to pass through doorways or past aisle bulkheads.
Furthermore, he observes, the IFE revolution is taking place at a time when airlines are becoming progressively more "discerning" about first- and business-class seats themselves.
In this market sector, he explains, there is no such thing as a standard seat. Every customer wants its own seat design, and seats are becoming more electrical (for adjustment) at the same time as becoming more electronic (for IFE). To add to the combinations the manufacturer has to meet, Rumbold supplies seats fitted with IFE equipment from every main manufacturer and, as Higgins points out, there is no standardisation yet in the inflight-entertainment equipment market. So everything from fasteners and connectors to screen size and telephone handsets varies. ARINC standards are being drawn up, but complete agreement and implementation will take years.
The one blessing, Higgins confirms, is that the demands of IFE in seats, despite the heat and additional electrical equipment, have not caused the regulators to demand a change of materials used - yet. These are already considered to have been proven safe. The demand for IFE has increased the need for flexibility, which has its effect on lead times and prices. Seats are also designed with a degree of built-in adaptability to allow for IFE updates or even supplier-changes, says Higgins.
Economy fits
The real challenge is to provide the economy long-haul passenger with IFE while not taking up any of the already limited space available. BEA, uniquely a maker both of furniture and IFE equipment, claims that, by coming a little later into the IFE market, it is the only company which has been able to make use of technology to take the equipment out of seats and centralise it. "Ours was the only system designed for nose-to-tail installation," says BEA's marketing chief Marco Lanza: "We changed the whole architecture to take it away from the seat and centralise it."
BEA's centralised IFE control systems do take up more space than those for seat-centred systems, Lanza admits, but the amount of space is far less than that taken by the seat-based equipment, he claims. Not only that, but as much of the BEA system as possible is located in unused areas such as the ceiling or above the galleys.
If the BEA system follows such impeccable logic, why does not every airline choose it? Lanza says that in its certificated form the equipment has been ready only since January 1997, and the first system was delivered to Japan Air Lines in March. British Airways has had the equipment installed for testing, but that took it through its "teething troubles" stage, Lanza insists. The system works well in its non-interactive form, showing a reliability rate of more than 99%, he says, but in its interactive form, the complexity is such that it there is some way to go yet.
Nevertheless, Lanza points out, airlines will persist with IFE because of the limitless on-board sales and marketing opportunities which a fully interactive system will offer. There are still some trade-offs which airlines have had to make for weight reasons, he says. Despite the fact that the BEA system can add as little as 2kg to an economy seat, that is extra weight, and airlines have tended to look for savings elsewhere: for example, by not offering a leg rest.
Maintenance has to be acomplished in quick turnarounds, Lanza says, explaining that BEA has made its seat-console equipment modular to help this. Any problems tend to occur in the mechanical components such as cable reels.
Some of these problems may diminish as IFE equipment becomes more digitised and therefore more compact, and as airframe manufacturers adapt their designs to the developing electronic technologies. It seems unlikely that, in the near future, the airline seat will revert from being a padded electronics rack to mere pieces of furniture on which passengers sit.
Source: Flight International
