Warplanes: April 26, 2002

Archives

The Defense Advanced Research Projects Agency is investigating ways that new materials could be used to create an aircraft able to change shape in flight. This would provide benefits in low-observability and performance. The fixed shape of an aircraft determines what mission it is best suited for and how it will perform. A shape good for speed may be bad for range; a shape harder to spot on radar may cost performance or weapons load. The only workable design-change aircraft to date have been the "swing wing" designs such as the F-111, B-1, and F-14, but these designs have a major problem (the weight of the wing-change gear box is considerable) and they have only a couple of options on their shape. What DARPA wants as a first step is an unmanned recon aircraft with a wing span under 40 feet that can fly at high subsonic speed. They want this aircraft to be capable of a 200 percent change in aspect ratio, a 50 percent change in wing area, and a 20-degree change in wing sweep. Most of the change will be in the wings, but other structures could change in more advanced versions. The engine inlets could be reconfigured for different speeds and altitudes, and the fuselage might even contract as fuel is burned. Another fascinating concept is the "virtual rudder", which could be extended when the aircraft needs to maneuver and retracted when cruising in straight and level flight. Control surfaces are major problems for a stealthy aircraft as they cause more reflection than a smooth surface. The B-2 uses split flaps to turn, and when they are deployed the aircraft is much easier to spot on radar. Making radical maneuvers in an attack run actually make the B-2 vulnerable to enemy air defenses.--Stephen V Cole


 


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