Warplanes: Prop Driven Satellite Replacements

Archives

January 13, 2011: After six years of development, the full size version of the U.S. Air Force Global Observer UAV reconnaissance aircraft had its first test flight. With a 56.5 meter (175 foot) wingspan and four electrically powered propellers, the aircraft can stay aloft for over 160 hours (a week) while flying at 21 kilometers (65,000 feet). Carrying about 400 kg (880 pounds) of vidcams and communications gear, the one ton Global Observer uses liquid hydrogen to run a generator that powers the four props and the sensors. 

Global Observer is basically a powered glider, thus it cruises at about 250 kilometers an hour. There have been attempts to build long-endurance UAVs like this using solar panels in the wings. But those aircraft are not as robust, nor can they carry as heavy a payload (or generate as much power) as those using liquid hydrogen, although the solar powered aircraft can stay in the air longer. Global Observer UAVs, costing about $40 million each, would be replacements for space satellites, as well as providing the usual "persistent" observation of terrain below.

Global Observer may never make it into service. There are reliability and durability issues that more testing and tinkering will answer, one way or another. The last five years have been spent scaling up the original, smaller, models of this unique aircraft type. The final version may even be a little bigger. But if all goes well, Global Observer could be operational in 5-10 years.

 

 


Article Archive

Warplanes: Current 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 


X

ad
0
20

Help Keep Us Soaring

We need your help! Our subscription base has slowly been dwindling. We need your help in reversing that trend. We would like to add 20 new subscribers this month.

Each month we count on your subscriptions or contributions. You can support us in the following ways:

  1. Make sure you spread the word about us. Two ways to do that are to like us on Facebook and follow us on Twitter.
  2. Subscribe to our daily newsletter. We’ll send the news to your email box, and you don’t have to come to the site unless you want to read columns or see photos.
  3. You can contribute to the health of StrategyPage. A contribution is not a donation that you can deduct at tax time, but a form of crowdfunding. We store none of your information when you contribute..
Subscribe   Contribute   Close