Article 59a of the UK Air navigation Order says
No person shall, while in an aircraft:
Use any threatening, abusive or insulting words towards a member of the crew of an aircraft; behave in a threatening, abusive or insulting or disorderly manner towards a member of the crew of an aircraft;or
Intentionaly interfere with the performance, by a member of the crew of the aircraft of his duties.
This offence covers the behaviour up to the assault and of the specific air offences may well be the most appropriate coupled with a charge under the offences against the person act (it is difficult to be specific without full circumstances). This offence is very general and will cover most cases of disruptive pax.
AP