Jurors in the case of a teacher accused of having sex with a pupil in a plane toilet have failed to reach a verdict.
Eleanor Wilson, 29, of Dursley, Gloucestershire, denied four counts of sexual activity with a child under 18 while in a position of trust.
She was accused of having sex with the 16-year-old on a school trip in 2015.
The Bristol Crown Court jury was discharged by Judge Peter Blair QC after more than 10 hours of deliberations.
Prosecutors have asked for seven days to consider whether to seek a retrial.