A Tory tax on air travel – flying a kite?

In a surprise move, the Tories have announced plans to tax air travel as part of their environmental policy. It was no surprise to hear the airlines criticise this, but disquiet about this policy has been expressed in traditional Tory circles and it amounts to a significant departure from the past for the party. Are they just flying a kite, or is this a serious policy initiative?

Tories reveal plans for green tax hike on air travel Guardian (11/3/07)
Tory plan for sky-high flight taxes Scotsman (11/3/07)
Airlines shoot down Tory ‘tax on fun’ Telegraph (12/3/07)
Green tax won’t help the planet or the Tories Telegraph (11/3/07)
Tories plan green tax on flights BBC News Online (11/3/07)

Questions

1. Why might a free market in air travel not result in an optimal number of flights.
2. Discuss the likely effectiveness of the tax on flying for reducing the demand for air travel. (You should consider the likely value of the price elasticity of demand in your answer.)
3. With the use of appropriate diagrams, assess the likely impact of the tax on flying on the equilibrium level of price and output in the market for air travel.