Well for anyone who wants to practise loops in a (civilian) ((gyroplane)) there is at least one firm that builds one sturdy enough to loop if you've got the moxie to loop a GyroPlane -
"Vortex Breaks New Territory for Gyros". Jim Vanek performs world's First Loop in a Vortex gyroplane at the PRA Convention in Mentone, Indiana, Summer 1997.
If you would like to witness this for yourself, tapes showing five loops & more exciting flying footage are available.
hover lover