aircraftcompare.com
contentzone.eurocontrol.int/aircraftperformance
ourairports.com
airliners.net
airlines-inform.com
http://www.skybrary.aero/
http://planes.findthebest.com/
http://www.the-blueprints.com/
http://www.greatcirclemapper.net/
http://flightaware.com/
http://www.b737.org.uk/techspecsdetailed.htm
http://m-selig.ae.illinois.edu/ads/aircraft.html
http://www.airlineroutemaps.com/
Weather
1- http://www.holiday-weather.com/averages/
2- http://www.weatherbase.com/weather/
3- http://www.esrl.noaa.gov/psd/data/gridded/data.20thC_ReanV2.pressure.mm.html
4- http://iridl.ldeo.columbia.edu/maproom/Global/Atm_Circulation/Sea_Level_Pres.html?T=Oct%202013
airports
http://www.worldaerodata.com/