My favourite aeroplane of all time... the Mudry Cap 10b. Developed by a Frenchman by the name of Claude Piel, the Cap 10 is an aerobatic derivative of his earlier "Emeraude" design. It has a Lycoming IO-360 developing 180 horsepower, and weighs just 1850 lbs (that is 50 pounds more than a Cessna 150). It is such a delight to fly, and is very responsive and manoeuvrable, but at the same time predictable and honest. Just what you need for teaching aerobatics.
The other photo was taken by a friend of mine whilst he was in another Cap 10b flying below us. We were inverted in what is known as "Mirror" formation, and our canopies were about 10 feet apart (vertical fins much less than this). My good friend Dave Robson was flying the second Cap 10 and we used to do this sort of thing quite often in the early 90's as the Cap 10b was quite unique in Australia at the time. These were the only two aircraft flying in Australia at that time. I still feel quite priveleged to have been involved as I was.
