(I) In recent years, there has been a dramatic increase in
flying. (II) Cheap flights, bigger airports and the
convenience of Internet-ticketing have made flying a far
more accessible form of transport. (III) However, this
increased freedom has come with a huge environmental
price. (IV) There are some modest technological
improvements that have made aircraft cleaner, but this
is not enough to compensate for the growth in flying that
continues. (V) The maintenance of an aircraft requires
an experienced staff, but engineers play the most
important role.