Book Review

Helicopter Life Book Review

Helicopter Aerodynamics made simple. An impossible oxymoron or teaching it right?

Geoff Day should know. Not only has he trained over 200 commercial pilots, he has been teaching for longer than most people have been flying. He has 21,000 hours of flying and an incredible 14,000 instructional hours. That is more than 2 years of non-stop flying and more than a year and a half of non-stop instruction.

In his book Geoff has attempted to make aerodynamics clear and simple for ab-initio helicopter students, the majority of whom do indeed find the how and why of helicopter flying very confusing.

The book starts by going back to basics and looking at Bernoulli's law. Then, with the help of diagrams, he puts this law into practice on a helicopter. Slowly he builds up the picture of flow into the blades, lift and drag and washout, before the moving onto the effects of controls.

Here he shows how all the factors looked at in the previous chapter affect the flying of the machine and how we use this knowledge to get the machine to do what we want it to. He works through the elements of flight, seeing how the aerodynamic principles affect the hover, transitioning, quickstops, autorotations and vortex ring, before moving on to the especially confusing bits.

The book has a chapter 'Awkward Bits' which looks at a number of aspects of helicopter aerodynamics which, he explains: "do not fit neatly into the chapters before." Here he spends time on the problems of: Flapping To Equality, Phase Lag, Advance Angle, (LTE) Loss Of Tail Rotor Effectiveness and Dynamic Rollover - all of which have had many a pilot perplexed in the past.

At the end of the book there is an appendix which looks at those things we know but sometimes forget: Axes Of Rotation, Stability and Tail And Main Rotor Heads.

In some ways you might call this a 'graphic aerodynamics book' as the intention is clearly to demonstrate the movement with pictures and then explain them in the text and this works very well.

More reviews

Purchasing Information

ISBN : 978-0-9566978-0-6
Price : £22.50 (£20 plus p&p)