Skyscanner,
LH 2010 (Page 49 of financial report)
Cost of Equity = 10.5%
Cost of Debt = 5.4%
Group WACC = 7.9%
A good spot but a few flaws with this. Firstly it is based off European debt rates which are structurally lower than Australia. The Lufthansa annual report claims a risk free rate of 4.2%, you can probably add 1-1.5% to this for Australian mid cycle risk free rates. Secondly, debt spreads at 1.2% look too low. Thirdly, it isn't independent, it has been calculated by Lufthansa to compare with their rate of return in order to cast this in a more flattering light (it is very easy to estimate beta to be anything you want it to). By contrast Goldman Sachs, (sorry no link) have a WACC for Qantas of 10.4%.
Also all of the above uses the CAPM which academics love since is theoretically pure but investors don't much use since the assumptions don't fit with reality and calculated betas aren't stable. In practice investors know how risky airlines are and most investors will demand a significant premium hence my comment that many would argue Qantas cost of capital should be significantly higher than 10%.