Questions

Cryogenic Engines find applications in Rocket technology. A cryogenic rocket engine is a rocket engine that uses a cryogenic fuel or oxidizer, that is, its fuel or oxidizer are gases liquefied and stored at very low temperatures. Notably, these engines were one of the main factors of NASA's success in reaching the Moon by the Saturn V rocket.

The U.S. e-commerce giant, Amazon has been awarded a patent for launching a giant flying warehouse that would acts as a launch pad for drones to deliver items within minutes.The patent reveals plans for setting up an “Airborne Fulfillment Center” (AFC) such as an Airship or Blimp, floating at an altitude of around 45,000 and stocked with lots of products especially in area where the demand for certain items is expected to be high. When a customer places an order, a drone or unmanned aerial vehicles (UAV) will fly down and deliver the package. The patent claims that this would require little or no power because the drone would be gliding down rather than having to take off and land.