Site Selection
Although difficult to achieve, good site selection including soil composition and drainage, is most important as boggy strips prevent more landings than any other factor.
Some pointers to natural surface airstrip site selection
- Look for areas that are naturally well drained and not subject to flooding or water ponding.
- Look for areas without frequent surface undulations. Ideally there should be a gentle fall along the length of the airstrip and a very slight camber on the runway. Pronounced one way slopes across the runway should be avoided - they can cause surface scouring.
- Give preference to sites having soil types that, from local experience, remain smooth and compact when trafficked.
Avoid:
- very sandy soils;
- rocky terrain;
- soils that become boggy or slippery when wet
Make sure that the selected site:
- can comfortably accommodate required airstrip dimensions and physical characteristics and is aligned into the stronger prevailing surface winds;
- avoids penetration of the approach and take off surfaces and the lateral transitional surfaces (where required) by immovable objects;
- remains accessible to normal surface transport at all times when the airstrip in useable.
Endeavour to select a site where:
- no hills (or terrain) or man made objects (masts, buildings, etc.) more than 45 metres above airstrip elevation exist within 2500 metres (ideally 4000 metres) of the site;
- aeroplanes will not fly close to or over residential or built up areas, particularly during normal landing and take-off phases of flight;
- future use of the airstrip is not likely to be compromised by the growth of obstacles around it.