FliteDeck Pro - ETOPS

FliteDeck Pro is a mobile application (iOS & Windows) used by commercial pilots in the cockpit. When flying over large areas without suitable airports available to divert in case of emergency, pilots must utilize Extended-range Twin-engine Operational Performance Standards or ETOPS. In other words, sometimes pilots must fly over the ocean or over extremely rural areas, and certain regulations apply to let them know exactly how far away from an airport they are allowed to be. Some airlines must always stay within 60 minutes of an airport, while others are allowed to be 180 minutes or more. In order to allow pilots to visualize their location in relation to their limits, “ETOPS rings” are displayed on the map. This project is a redesign/improvement of an existing feature of the application.

 

Discovery

The initial implementation of ETOPS within FliteDeck Pro was relatively simple. Pilots could choose to hide or show the rings for their flight. When displayed, three rings appear around each airport along the route - 60 minutes, 120 minutes, and 180 minutes (shown below in dashed brown lines).

 
 

I conducted interviews with Product Management and customer pilots to understand where the initial implementation was falling short. We found that the depiction tended to clutter the pilot’s view of the map due to the intersecting rings over the route. We also found that having only preset values was too inflexible for rapidly changing daily operations because allowable ETOPS distances can change based on the weather forecast.

 

Initial Design & Testing

In order to solve the two main user problems, we first needed to expand the options available for ETOPS. In the initial implementation, rings were only allowed to be ON or OFF.

First, we tackled the the cluttered display issue. We introduced alternate ring style where lines in between intersecting rings would be hidden (see “scalloped” mode in the image below). One of our airline customers used this depiction method in their own charts, but it wasn’t a pervasive depiction in the industry. We also added the ability to hide one or more pre-defined rings from the map.

In addition to decluttering, we also wanted to solve the problem of inflexibility. To this end, we added the ability to create rings with custom distances. This would allow users to enter the specific ETOPS distance they were given on their flight plan in addition to or instead of the pre-defined distances.

Due to COVID 19, we were unable to conduct in-person usability testing as our normal rigor dictates. However, we are able to conduct virtual scenario-based testing with our airline customers using a clickable prototype and video conferencing software. The test script format I used is shown below.

 
 

Test results showed that users could not accurately predict what they would see if they selected “Scallop”. They also were not confident if the minutes and distance measurements were for their specific aircraft. We also determined that most pilots receive their day-of ETOPS information as a distance, rather than a time. Pilots also told us that it would be a good idea to place limits on the custom rings - a minimum and maximum distance allowable. Luckily, despite these drawbacks, the users really appreciated the value that the additional functionality would provide.

 

Design Iteration & Validation

For the next round of design concepts, we wanted to fix the three main usability issues we found in the first round of testing:

  • “Scallop” terminology unfamiliar

  • Unsure of applicability of data with current aircraft

  • Custom ETOPS rings should be based on distance rather than time

In order to fix the issue of the use of the word “scallop”, we made two changes. First, we determined “Combined” to be a more clear word. Additionally, we added a small pictogram of each style above the word and selection to hopefully make any terminology confusion moot.

In order to clarify that the pre-defined ETOPS distances were specific to the pilot’s currently selected aircraft, we were able to reuse an existing component from the application called “fleet tags”. These are small indicators throughout the application that display the user’s currently selected aircraft fleet. By placing the fleet tag at the top of the view, we hoped that users would intuit that the values below were directly applicable to their aircraft.

Lastly, we updated the custom distance entry to be in Nautical Miles rather than the previous entry in minutes. We also added the ability to delete custom distances so that users would be able to clean up their view and not keep around old custom distances from previous flights. After some additional review of what a “reasonable” range could be on a global scale, we added an allowable range for custom distances to be between 350 NM and 4000 NM. Updates to the ETOPS selector are shown below.

 
 

We were able to conduct an additional round of virtual tests with our users and the feedback was overwhelmingly positive. The addition of the pictogram to illustrate the difference between Rings & Combined displays was particularly well-received.

 

Implementation & Outcome

Out of the last round of user testing, I created a behavioral specification for the developers who would be implementing the feature. One of the items we added into the design during this phase was an error state for custom distances that were entered outside of the allowable range.

After the feature was implemented, we received overwhelmingly positive feedback from our users, particularly around the ability to declutter the map with the Combined display and the ability to add custom distances to match their flight plans “on the fly”. One user quote is shown below.

Loving the new combined ETOPS rings view. Our crews will love it now that we are crossing the pond, they are going to be so anxious to see [it] in the next build. - FliteDeck Pro Customer