HUMANITARIAN AIR DROPS: A COMPLEX, RISKY TASK

The UN wants Damascus to allow airdrops of food and medicine to civilians trapped in besieged areas which aid convoys cannot reach.

592K people live under siege in Syria, the majority surrounded by regime forces

4m live in hard- toreach areas

The planes sending aid need to be able to fly in a secure airspace, either with the agreement of warring parties, or by flying at very high altitude to escape missile

If Syria gives green light to the UN, tight coordination would be required between the Russia and the US who are both active in Syrian skies

If the planes do not have security guarantees, they will have to parachute aid packages from a very high altitude. Using a parachute, items can be dropped from up to to 8,000 metres.

Another alternative was using a helicopter which can make a drop from a few dozen metres. However, this is high- risk.

The load that a plane can carry is a lot less than the amount that a road convoy can take. There was also always a risk that cargo did not fall into the hands of those who needed help.

If security is ensured, the plane can descend to an altitude of 50m. In addition, finding those willing to send their planes into Syria to carry out the drops could be a challenge.