Sources of data for airport, ATM, passenger etc data

The main sources of data are:

CAA    Covering all traffic into and out of the United Kingdom – www.caa.co.uk/airportstatistics
 
Figures for all reporting UK airports for the month before come out around 15th of each month – though final statistics await reports from the airports which are slower to submit figures.   Provisional till finalised.  (Once finalised, there are very slight differences between the provisional and the final figures – for which no explanation is given).
 
BAA    News releases –   Figures for the month before, at BAA’s airports, come out around 10th of each month.
 
IATA   Press releases on global traffic – Include an overview of the previous month, around 4 weeks later around 25th of each month
 
AEA   Figures for European airlines, weekly, monthly and anually. http://www.aea.be/research/traffic
 
RDC AviationIntra European Capacity Statistics.
RDC produce a free analysis each month of all airports and airlines in Europe.  Only free if you register to have them emailed to you.     Intra European Capacity Reports. For example  Intra European Capacity Report June 2010
RDC Aviation – UK Passenger and Cargo Monitor    
RDC produce a free analysis each two months of all airports and airlines in the UK.   Only free if you register to have them emailed to you  UK Passenger and Cargo Monitor
 
Anna Aero   European Airport Traffic Trends   and  European Airline Traffic Trends    These show data for Europe, and all European airports, not only those in the UK