Presumably fearing some Desperado-like stowing of weapons in guitar cases, the British government has decided not to force airlines to permit musicians’ bringing their cases aboard. A petition brought the issue before the likes of one Lord Clement-Jones, who supported the measure, as reported by NME:
There are terrible cases where valuable and cherished instruments are smashed in the holds of aircraft as result of musicians not being able to take them on board with them.
It appears that flying with your instrument will remain a risky proposition.
Read the entire NME article right here.