Solar Powered Unmanned Aerial Vehicle "Zephyr"

The Solar Powered Unmanned Aerial Vehicle "Zephyr" is part of a class of aircraft called HAPS, or "High Altitude Satellite Mimicry". The Zephyr produced by Airbus in the United Kingdom, the Phasa 35 produced by BAE Systems, the Skydweller produced by Leonardo, and other Stratospheric Platforms are in the HAPS class. These vehicles fly in the stratosphere, the layer of the atmosphere we call the stratosphere, at altitudes of 70,000 feet or more, for a very long time without landing.

As the name suggests, HAPS aircraft can perform some of the tasks performed by satellites at a much cheaper cost. They can be used in areas such as reconnaissance, intelligence, image reception and transmission, control of land borders, control of maritime borders, atmospheric observation, communication signal transmission, 5G broadcast point, meteorological information collection, and they attract the attention of armies, commercial institutions, scientific research centers and government agencies.

The reason why the US Army of the Future Command, which has a large number of satellites, spy planes and drones, is using the UK-built Zephyr 8 HAPS class aircraft, despite its other capabilities, is that this vehicle is much cheaper than satellites and can be controlled from the ground to perform new missions at high altitude and slow speed between different geographical regions thousands of miles apart.

At 4 a.m. on August 19, the Zephyr 8 aircraft broke the record for the longest drone flight before crashing over the Arizona desert in the United States. The Zephyr 8 crashed over the Arizona desert, hours before it was set to break the record for the longest time in the air, 64 days and 22 hours, set 60 years ago by a Cessna 172 aircraft with two pilots on board.

Zephyr flew 30000 nautical miles (about 55000 kilometers) in its 64-day flight. The Zephyr aircraft weighs only 75 kilograms, but the distance between the tips of its wings is 25 meters and there are many solar cells on its wings. The aircraft is powered by solar cells during the day, but at night it uses lithium sulphur batteries to store the energy collected during the day. It is stated that the reason for the aircraft's crash may be that the lithium sulfur batteries lose their energy storage capacity after a large number of charge-discharge cycles. The fact that this very light aircraft encountered turbulence at high altitude could also be the cause of the crash. The Zephyr aircraft could be controlled via SATCOM from three different locations: Huntsville, Alabama; Yuma, Arizona; and Farnborough, UK. 

In addition, while the aircraft was over US airspace, direct data transfer was possible via datalink from the ground. Although the Zephyr was in the air for 64 days, it did not break the record for the longest time in the air. This record belongs to pilots Bob Timm and John Cook, who flew a Cessna 172 named Hacienda for 64 days and 22 hours between December 4, 1958 and February 7, 1959. The plane was able to stay in the air for so long because it was refueled at regular intervals through a hose from a truck carrying fuel underneath. It took about three minutes for the plane to fill its fuel tank. This record-breaking flight was an advertisement for a casino in Las Vegas. Today, the record-breaking airplane is on display at Las Vegas International Airport.

The record-breaking Cessna 172 airplane named Hacienda.