Recently I was asked to sign what I would consider a penalty clause at a school where I am adding to my woes by taking helicopter instruction.
When you sign things in the UK and you are entering the contract as yourself (i.e. not acting in capacity of employee/director of a company) ... there is a lot of protection under UK law !
UCTA and UTCCR are two big names ...
Unfair Contract Terms Act and Unfair Terms in Consumer Contracts Regulations
The OFT provide a few examples of unfair terms ....
http://www.oft.gov.uk/shared_oft/rep...311annexea.pdf
To put it in a simplistic fashion, if a term is unfair, then it is not enforceable, even if you signed a piece of paper agreeing to it.
Companies trying to incorrectly exclude death, injury is quite a common occurence....
Unfortunatley PPRuNe is no place for legal advice, suggest you talk to a lawyer about your concerns.