Asked by: Billy Doyle, by email
Many airports do have slightly sloping runways – the small landing strip at Santa Catalina near Los Angeles is one example. But a decline doesn’t aid take-off, or an upwards slope help with landing. Given the power needed to get airborne, a slope makes little difference either way. The most important factor is wind: planes take off with the wind to maximise airspeed, and land into it.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.
![By Leonid Faerberg [GFDL 1.2 (http://www.gnu.org/licenses/old-licenses/fdl-1.2.html) or GFDL 1.2 (http://www.gnu.org/licenses/old-licenses/fdl-1.2.html)], via Wikimedia Commons](https://images.immediate.co.uk/production/volatile/sites/4/2009/07/Sukhoi_Su-47_Berkut_S-37_in_2001-698c004.jpg?quality=90&resize=620%2C413 "By Leonid Faerberg [GFDL 1.2 (http://www.gnu.org/licenses/old-licenses/fdl-1.2.html) or GFDL 1.2 (http://www.gnu.org/licenses/old-licenses/fdl-1.2.html)], via Wikimedia Commons")
