ACCESS Lavatory interior ariel view

Extendable lavatory brings comfort and dignity back to passengers

Details and Design banner with text on graph paper backgroundDignity is coming back to the airline lavatory, which in recent years has been a source of growing complaints from passengers. At best they find newly slimmed-down lavatories on narrowbody aircraft difficult to move in, or more seriously have to enter backwards if they cannot turn around once inside. Visits to constrained lavatories will grow as narrowbody aircraft fly more long-haul routes.

Even worse is the experience for people with reduced mobility (PRM), who may only be able to use a lavatory if the door stays open with just a flimsy curtain for privacy. PRMs may try to avoid a lavatory visit altogether, forgoing meals and fluids in-flight.

ST Engineering and Acumen’s new Access lavatory, debuting at the Singapore Airshow, has two goals: give practical room for passengers while satisfying airlines’ quest to reduce floorspace. The trick is realizing that these needs occur at different stages in the journey. Lavatories are mostly used in-flight while cabin configuration is strictest during takeoff and landing when aisles and exits need ample room, which becomes excess floorspace in-flight.

The Access design, with the same footprint as a D-lavatory, is proposed to be at the rear of the Airbus A320 and Boeing 737 on the right-hand side. Whereas the door would typically face the aisle, the Access door faces the galley.

Access lavatory interior showing d shape and extra space

An extendable sidewall and the door can be moved 13 inches into the galley, with part of the door frame flapped around the emergency exit and its slide pack. This creates 40% more floorspace and allows for a 24-inch diagonal entrance.

This is the first time a lavatory will have an “expander”, which creates more space for general passengers and those of size; Access is designed around a passenger in the 95th percentile. “We wanted a lavatory that felt bigger for everyone,” ST Engineering VP commercial business Hean Seng Tan says at the Singapore Airshow. They are also examining airline interest for an expander on an E-lavatory.

Tan says they partnered with other ST Engineering divisions to use weight-saving materials to offset the expander’s weight, resulting in no net weight gain.

The idea is partially prompted by the US Department of Transportation’s long-running evaluation of improving passenger accessibility on narrowbody aircraft. This culminated last December with a proposed rulemaking some see as weak, not applying to new aircraft until three years after the rule is finalized, and not requiring retrofits to existing aircraft.

However, ST is first pursuing certification with EASA, partially because of its familiarity as an EASA DOA, and also due to market expectations. “We feel Europe is more sensitive to the topic and will be implementing before the US,” Tan says. STC is aimed for October 2020 on the 737 and first quarter 2021 for the A320. The first certification goal is 737, which has limited room at the rear due to more prominent fuselage tapering. “That’s the harder aircraft,” Tan says.

ST largely kept the product quiet while securing patents before this week’s launch, opening the company to meeting airlines. “That’s what we’re doing at Singapore as well as AIX,” Tan says.

Aerial view of the Access Lavatory interior

There are already discussions with two undisclosed US airlines, with ST targeting what Tan describes as “experience airlines that have inclusiveness as part of their model. Regardless of the DOT ruling, they want to bring dignity back to flying.

Initial airline discussions are about sales and marketing and will next involve operations and maintenance. Cabin crew support will be important. They will operate the extender, and even when not in use passengers will have to enter and exit the lavatory via the galley, which many crews like to curtain off.

The additional space from Access is clear. So too is its modern interior. Less obvious is the interior redesign to make it PRM-friendly while also being cohesive and not appear as if a grab bar was randomly tacked on. ST Engineering observed PRMs used the sink and toilet for hand support.

Besides hygienic factors, those parts could be wet, creating a slipping hazard, or not designed for abuse loads. Access has a support bar near the toilet basin and one integrated into the sink module, which can be placed at different heights but is proposed to be lower than usual so a PRM can wash their hands from the toilet before being transferred off.

Airline-specific benefits include re-locating the water shut-off valve so it can be accessed without dismantling the shroud. ST hopes to later gain linefit status, but meanwhile its historical retrofit focus gives it insights how to improve products. “We wanted to know where OEM parts are failing, and work with PMAs [personal mobility aids],” Tan says.

sink in the ACCESS Lavatory interior

All images credited to and courtesy of Acumen

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  1. Sebastian Tivig

    Dear All,

    new solutions for PRMs are always a good idea. And the idea of expanding lavatories is a good one – but not new. Diehl has presented a fully extendable lavatory (using the space of doors 2 or 3 on A321, but adaptable to any door area) decades ago – there was even a 1:1 mock-up at the Diehl facilities for quite some time. Ultimately, the concept was ditched due to insufficient interest from airlines (as far as I know).

    There are also some inconsistencies and some remarks, which can be made.
    First, there are solutions for single aisle aircraft as of today, which are Skypax and Space-Flex v1 (Diehl and Airbus respectively), which provide full PRM access, while also increasing revenue space for the airline (an important aspect to consider in an ever competitive market).
    Second, pushing the door to the cross-aisle does interfere severely with the way the crew works. Whereas on Skypax / Space-Flex the aft space is essentially separated (left galley / right lavatory), in this case you have a full mixture of lavatory and galley spaces, which is very uncomfortable for the crew. Even with Space-Flex there are many airlines where cabin personnel is not too happy about the mixture of spaces; this will be even worse.

    Then, there are some inaccuracies as to the article itself:
    The statement that the counter-top and / or wash basin may not resist abuse loads is wrong. In accordance with EASA / FAA requirements (just recently re-inforced by a coordination memo), all parts which can be reasonably used and hand-holds / supports will resist 90 daN force (usually downwards and sidewards, push and where necessary pull), which is the case of all counter-tops, wash basins, faucets and more. It would be correct to say that grab bars typically have higher use loads, but even then, I have never seen a wash table be destroyed by abuse loads…
    The statement about dismantling the shroud for the water shut-off valve is also false. Security on the airplane mandates that it is possible to shut off water without the need for disassembly, in case of a leak. Again, this is a case of getting your lavatory certified. Some lavatories have the shut-off valve behind an access flap in the floor pan (again, easy access) or have a remote control behind the wash table door.

    All in all, while I highly commend ST Aerospace and Acumen for trying to do some good for the growing number of PRMs, the direction they are taking is neither new nor promising. And some of the article could have been researched a tad better.


    Some disclaimers: This is my personal opinion and not necessarily that of my employer. I am currently employed by Diehl Aviation, but have also worked for Airbus and on my own account. I have not been paid or otherwise incentived to make the above statement. And if you need additional information then please drop me a mail.