A number of American Airlines planes have been grounded in the US following an issue with on-board iPads used by pilots.
The unspecified problem, within an application on the iPads that provides mapping and flight planning information to pilots - understood to be the Jeppesen mobile terminal chart application - meant the planes were unable to take off.
Reports by passengers on Twitter suggest the iPads were shutting down unexpectedly, restricting the pilots from being able to access their flight plan.
American Airlines said in a statement a few dozen planes were affected and had to return to the gate to access a wi-fi connection in order to fix the issue.
It said it was working to remediate the problem.
In 2013 American Airlines announced it would deploy more than 8000 iPads to cockpits as a replacement for the pilot's flight bag, which contained 16kg worth of paper documents.
At the time the airline said it expected to save at least 400,000 gallons of fuel and US$1.2 million annually by removing the extra weight from the plane.
The iPad is loaded with reference materials pilots are required to carry. The pilots use software provided by Jeppesen, a division of Boeing Digital Aviation, on the devices.