CrowdStrike Outage Clips Delta’s Wings

Key Takeaways:

• Mobile web was the platform of choice for stranded passengers, comprising over 50% of total US users for each airline in the cohort, per Sensor Tower’s proprietary desktop and mobile web panel data

• While Delta’s rivals have seen a downtick in traffic on their US mobile web and desktop sites since the peak of the outage, Delta’s traffic continues to be high, as it faces ongoing scheduling and performance issues

  • Looking at the growth of the average number of DAUs on the cohort’s mobile web sites over a rolling 7-day basis and compared to the same day the prior week, Delta’s mobile users are up an average of 23% WoW from 7/19 to 7/24, compared to 14% WoW and 6% WoW for United and American, respectively

• The cohort’s mobile app trends differed from the cadence of desktop and mobile web trends, with both United and American seeing accelerated app usage growth on a rolling basis in the days following the outage, on a rolling basis, each up 11% WoW on July 23. In contrast, Delta’s mobile app saw only 7% WoW growth on July 23

  • This suggests that American and United’s surge in activity is likely related to normal business issues versus the outage

• As expected, user engagement on the mobile web and desktop sites for each of the airlines rose in the period surrounding the outage, though Delta saw the greatest gains. Delta’s weekly average session count on desktop rose 12% WoW for the week of 7/14, followed by another 7% WoW gain for the partial week of 7/21

Mobile Web is Platform of Choice for Stranded Passengers

As fliers scrambled to make alternative flight arrangements amidst the fallout from the CrowdStrike outage, all of Delta’s US digital properties saw significant surges in traffic. Mobile web had the largest penetration of users for Delta and its rivals, American Airlines and United Airlines. On average, US mobile web comprised 61%, 53% and 52% of all users for American, Delta and United, respectively, from July 19 through July 24. This was an increase of nearly 6ppts, 3ppts and 2ppts for Delta, American and United, respectively, from the prior week. This is likely due to travelers, who may not have the mobile app or did not have access to a desktop computer, searching the companies’ mobile websites to get in touch with agents to make flight changes from the airport. The fall in mobile app penetration from July 19-24 may also suggest that the mobile apps did not have the functionality to deal with travelers’ issues due to the nature of the system outage.

Delta’s Mobile Web and Desktop Traffic Remains Elevated While Rivals Return to Normalized Levels

While Delta’s rivals have seen a downtick in traffic on their US mobile web and desktop sites since the peak of the outage, Delta’s traffic continues to be high, as it faces ongoing scheduling and performance issues. Per Sensor Tower data, on July 19th, US mobile web DAUs spiked 71%, 47% and 34% DoD for United, Delta and American, respectively. However, Delta continued to see DoD growth, up another 4% DoD on July 20 and 18% DoD on 7/22. Looking at the growth of average number of daily users on the cohort’s mobile web site over a rolling 7-day basis and compared to the same day the prior week, Delta’s mobile users are up an average of 23% WoW from 7/19 to 7/24, compared to 14% WoW and 6% WoW for United and American, respectively, over the same period.

Trends were similar on the airlines’ US desktop websites, though the rate of growth was smaller, given the user preference for mobile web, as described above. Looking at the growth of the average number of DAUs on the cohort’s desktop websites over a rolling 7-day basis and compared to the same day the prior week, Delta’s desktop users are up an average of 22% WoW from 7/19 to 7/24, compared to 5% WoW and 4% WoW for American and United, respectively, over the same period.

The cohort’s US mobile app trends differed, with both United and American seeing accelerated app usage growth on a rolling basis in the days following the outage, with each up 11% WoW on July 23. In contrast, Delta’s mobile app saw only 7% WoW growth on July 23. From 7/19 to 7/23, United had an average daily WoW user growth of 8% compared to 5% for both Delta and American. This suggests that American and United’s surge in activity is likely related to normal business issues versus the outage.

Desktop and Mobile Web Engagement Jumps

As expected, user engagement on the mobile web and desktop sites for each of the airlines rose in the period surrounding the outage, though Delta saw the greatest gains. Delta’s weekly average session count on desktop rose 12% WoW for the week of 7/14, followed by another 7% WoW gain for the partial week of 7/21. While United saw a 3% WoW increase in session count the week of 7/14, average session count fell 3% WoW for the partial week of 7/21, while American had <1% WoW gains for both weeks. This suggests that users may have needed multiple sessions/attempts to reach a Delta representative to make flight arrangements. Even more interesting, comparing average weekly session count on desktop for the partial week of 7/21 compared to the week of 6/23 shows a 22%, 8% and 3% jump in sessions for Delta, American and United, respectively. Similarly, average session count/day on mobile web for the partial week of 7/21 rose 15% WoW for Delta, while both American and United saw a fall in session counts, down 21% and 18% WoW, respectively. While Delta saw gains in mobile web session count, its rivals saw flat to declining session count for the week of 7/14 and 7/21.

Growth in average time spent on the desktop websites and mobile web differed from average session count trends, and skewed to mobile web, though both platforms saw a jump the week of 7/14; Delta in particular, saw a 26% WoW increase in mobile web time spent, followed by United at 8% WoW and -6% WoW at American. Desktop time spent rose 17% for Delta for the week of 7/14, followed by an additional 4% WoW gain the partial week of 7/21. While United saw a 12% WoW jump in desktop time spent for the week of 7/14, this fell 9% WoW the week of 7/21, American’s trends were the opposite, down 8% WoW the week of 7/14 and up 9% WoW for the week of 7/21. The difference in time spent trends versus session count trends align with usage trends, with more engagement growth on mobile web versus desktop, though on an absolute basis, time spent is traditionally higher on desktop.

Delta Gets Back on Its Flight Plan

Fortunately for Delta, it seems that the situation is slowly getting under control, with CEO Ed Bastian stating that “Thursday is expected to be a normal day, with the airline fully recovered and operating at a traditional level of reliability." However, Delta could continue to face a financial hit from refunds and any fines levied by the government. After Southwest’s snafus in 2022, it was fined a record $140mn.

For more information around this report or Sensor Tower's offerings, please contact sales@sensortower.com.