Not quite as straight forward as Genghis the Engineer thinks. If criminal charges are brought against those involved then it is likely that the matter will be brought before the Crown Court and it will be up to a jury to decide the verdict. That will be a lay jury and given all the complex and technical nature of such a case, the AAIB investigation report, together with the opinions of expert witnesses for both the prosecution and defence will be crucial to such a trial.
The offence most likely facing the defendant(s) would be:
"SERA.3101 Negligent or reckless operation of aircraft
An aircraft shall not be operated in a negligent or reckless
manner so as to endanger life or property of others".
If the above is proven, the crime of involuntary manslaughter, where there was no intention to kill or cause serious harm but death was the result of an unlawful act or from gross negligence, must therefore follow.