How Things Work - Afterburners
Jets get no kick from champagne, but a little fuel in the tailpipe...
- By Damond Benningfield
- Air & Space magazine, July 2007
Airman Apprentice Nathan Laird, U.S. Navy
(Page 3 of 3)
With afterburners, the open tailpipe welcomes enemy radar waves, which enter the hole and bounce back a strong signal even when the afterburner is not lit.
It is also nearly impossible to hide the infrared emissions from a lit afterburner and its nozzle—structures that stealth airplanes like the B-2 and F-117 don’t have.
Using a turbofan, which mixes cool air with the turbine exhaust gases, helps decrease the signature a little.
Future designs, featuring afterburner nozzles built into the fuselage and cooled with bypass air, may mask the jetpipe’s infrared emissions. Engineers also are evaluating construction materials that absorb heat, similar to space shuttle thermal tiles, and other engine designs that would create stealthier afterburners.
But there is no way to fully hide a plume of hot air roaring from the back of a warplane. The only way to preserve stealth is to reduce the reliance on afterburners. The F-22A, for example, can cruise at about 1.5 times the speed of sound without lighting the afterburner.
Still, aviation engineers say afterburners will remain in use well into the 21st century. Although carrier takeoffs are the most common of current uses of the afterburner, extra speed is always useful in combat. As long as military pilots might need extra bursts of power, afterburners are likely to remain the solution.