Released: 5 Aug 1998
EGLIN AIR FORCE BASE, Fla. (AFNS) -- An Advanced Medium Range Air-to-Air Missile, or AMRAAM, special test asset called an Instrumented Measurement Vehicle will soon start flight tests here.
This is the first of four IMVs built to measure the flight environment AMRAAM missiles experience when flown on fighter aircraft.
"We are excited about this new test vehicle because it will do a better job of gathering AMRAAM vibration data and give us confidence in our hardware improvements before they are fielded," said Judy Stokley, system program director of the Air-to-Air Joint Systems Program Office.
During the past decade, the AMRAAM has had a number of structural and component changes made to lower its cost and improve its performance.
AMRAAM engineers and managers decided it was time to re-measure its flight environment to ensure all parts of the missile would have long life. To accomplish this, a new, state-of-the-art IMV was proposed by Raytheon and approved by the JSPO.
After 16 months of design, manufacture and test, the new IMV is a reality.
After being checked for weight and balance and cleared for flight, the IMV will be mounted on a 46th Test Wing F-15 and flown for a series of 12 flight tests during August and September.
The primary purpose of these tests will be to measure the vibrations AMRAAM missiles experience when carried by fighters in various combat conditions.
Up to 48 sensors inside the IMV measure vibration levels, temperatures, pressures, and accelerations on AMRAAM missile critical structure, guidance, control, and warhead components.
"We can measure the environmental impact of flying on the missile in the real world," said Jean Marie Moore, Raytheon program manager.
Those measurements are signal conditioned and recorded by a device called a "flash random access memory," which is similar to the hard drive in a personal computer.
Upon landing, the data is downloaded to a personal computer where it can be analyzed by engineers and processed for test reports.
Disturbed airflow caused by abrupt maneuvering and engine throttle changes can cause missile fin failures and internal component damage. Because of this, it is important for engineers to understand the vibration levels the missile must withstand so they can design and test parts to survive them.
An essential design feature is ease of use. It will fit on any regular AMRAAM missile launcher with no aircraft modification required, according to Dave Brown, Raytheon senior scientist.
"The biggest feature is there is no aircraft modification required to carry it," he said. "Before, it would take two to three months and hundreds of thousands of dollars to modify the aircraft to carry the missile; not having to do that is a real plus."
Flexible record times are also possible. The IMV can record 90 minutes of data continuously or be switched on and off as required. Rapid turn around is another feature. After a flight, the data can be quickly downloaded and the IMV prepared for another flight without being removed from the aircraft.
This IMV looks just like the latest version of the AMRAAM missile. It has the weight, structure and same internal components as the Block 5 AIM-120C-5 missile that will be delivered to war fighters starting in 1999. The main differences between the IMV and a tactical missile are the IMV has an inert warhead, and its rocket motor case houses a data recorder rather than propellant.
In December 1998, two of the new IMVs will go to Edwards Air Force Base, Calif., to support the Air Force's F-22 Raptor flight-test program. (Courtesy of Air Force Materiel Command News Service)
RELATED SITES
* Edwards Air Force Base, Calif.
* Eglin Air Force Base, Fla.
