The unmanned aircraft will make deliveries using a biodegradable parachute.
A service using drones to deliver blood to far-flung clinics and hospitals was launched on Friday in Rwanda, a move that has pleased doctors in the region who are often stranded without life-saving blood supplies.
Rwanda uses about 650,000 units of blood per year. Almost half of that goes to mothers who suffer postpartum bleeding and another third is for children under the age of five who have malaria-induced anaemia, according to Keller Rinaudo, a 28-year-old Harvard graduate, who is the CEO of the drone project.
Zipline, a California-based robotics company, launched the service using drones to deliver blood to clinics and hospitals in hard to reach places in the East African nation that is also known as The Land of a Thousand Hills.
"Our long-term goal is to deliver the entire medical supply chain. So we plan to deliver vaccines, rabies prophylaxis, anti-venom, oxytocin as well as a whole host of other medical products that hospitals might have run out of," said Rinaudo.
The 13-kilogram (29 pounds) drones will be able to make a round trip of 150 km (93 miles), he said, as a small drone flew by a crowd of onlookers on Thursday before dropping a packet of blood to a waiting nurse in a demonstration.
The drones are launched into the air using a catapult and deliveries are made using a biodegradable parachute.
Espoir Kajyibwami, medical director of Kabgayi Hospital, said the service would help provide scarcer blood types that the hospital did not usually have at hand.
"When we need it we will have it quickly."
Rinaudo said the Rwandan government had signed a deal to pay for each delivery, but did not give any more details.
The Rwanda scheme is backed by a partnership between Zipline, global logistics company UPS and Gavi, an international vaccine alliance supported by governments and private donors.