Instruct: Classify Amazon reviews into positive or negative sentiment
Query: The best book on indoor aeromodeling!

Ron William's book Is an incredible resource for indoor flyers. Indoor models have seemed mysterious even to many outdoor flyers, but this book shows how to go from a simple Delta-Dart like glider to world class F1D planes weighing around 1 gram. Although the Aircraft types are a bit dated (Easy-Bee is now rather difficult, F1D planes are now much smaller and covered in plastic, Superthin plastics replaced many other coverings...)The building techniques are the same, and so are the formulas for loading and prop-form carving. Contest flyers should also get Lew Gitlow's newer book "indoor flying models" but William's Book is a truly indespencible resource.