While the U.S. Military has had fighter aircraft capable of supersonic flight for many years, such fighters typically had to slow down to lower speeds to deploy munitions correctly. The bane of every warfighter, the attack sequence is most stressful and vulnerable point during a sortie.
Bombs released at supersonic speeds cannot effectively exit a conventional bomb bay. Air vectoring can actually push the bomb back towards the aircraft at very high speeds.
Boeing and the U.S. Air Force have announced a new technology called High Frequency Excitation Active Flow Control for Supersonic Weapon Release (HIFEX) that enables the safe release of munitions from a weapons bay at high supersonic speeds. The demonstration of the HIFEX technology was performed using a rocket sled. The active flow control technology itself consists of a tandem array of microjets upstream of the weapons bay that disrupt the high-speed airflow enough for munitions to exit the bomb bay.
"As it was, the active flow control microjets reduced the unsteady pressures inside the weapons bay and modified the flow outside the bay to ensure that the test vehicle went out of the rocket sled nose up," said Bill Bower, Boeing Phantom Works program manager for HIFEX.
The sled the tests were performed on was powered by two pusher sleds and achieved 438,000 pounds of thrust for about 5.9 seconds on the first stage, 575,000 pounds of thrust for 3 seconds on the second stage and 115,000 pounds of thrust for 3.6 seconds on the third stage.
The JDAM (Joint Direct Attack Munition) test weapon was released from the sled at a velocity of about 2000 feet per second. Additional full-scale tests of the HIFEX system will be conducted by Boeing and the U.S. Air Force 846th Test Squadron in 2008.
This technology could lead the way or new fighter aircraft like the F-35 being able to drop smart munitions from supersonic speeds, allowing them to coast miles to the target greatly reducing the threat to U.S. soldiers.