Arena test produce goliath data

  • Published
  • By Airman 1st Class Anthony Jennings
  • 96th Air Base Wing Public Affairs
EGLIN AIR FORCE BASE, Fla. --  Standing 1,500 feet away, tightly tucked in the safety of a bunker, they stand and wait. This is the moment most have been working to complete for weeks. While looking at the multitude of screens in the room, the silence is only overcome by heavy breathing of the customers, fire fighters, explosive ordinance disposal team, base leadership and contractors that helped make this possible. Finally a bright flash appears on the screen, and only a moment passes before it is felt. The sudden jolt that sweeps beneath their feet catches them off guard, but prepares them for one of the loudest booms few people get the opportunity to hear. Well, at least hear and live to tell about it. 

At the request of the 685th Armament System Squadron, a horizontal arena test of BLU-109X/B filled with AFX-757 explosive in accordance with the Joint Munitions Effectiveness Manual was conducted by the 780th Test Squadron. This was the first of two horizontal tests, and a number of vertical arena tests required to sample the entire beam spray of the munitions. 

The purpose of these tests is to collect fragmentation and blast characteristics data for the Joint Air-to-Surface Weaponeering System, a database containing detailed information on the performance of munitions. 

"The test went without a hitch," said Captain Rowland Rosario, 46th Test Wing executive officer. "The bomb went off as planned, safely with a lot of data collected." 

The BLU-109X/B has the same case as the BLU-109/B with a few modifications including the upgraded, insensitive explosive fill, ventilated base plate assembly, PBXN-110 booster and reinforced fuse well assemble. The 595 lbs. of upgraded insensitive explosive fill is more energetic and less likely to detonate unintentionally compared to the 525 lbs. of net explosive weight of tritonal explosive fill used in the BLU-109/B. 

Seventy-four 16-ft fiberboard collection bundles have been positioned in a 180 degree, horseshoe-shaped arena to catch the fragments from a portion of all 36 polar zones without deforming them. The 36 polar zones are five degree angular slices surrounding the test item. 

Velocity screens are "make" screens consisting of cardboard with aluminum on both sides, and have been placed on the face of each bundle to record fragment velocities by five degree polar zones. The fragment velocities are calculated by differencing the time between the event occurring when a given fragment completes the circuit between the two foil layers on the face of the bundle and the initial flash of the warhead detonation. Six piezoelectric pressure transducers have been situated in three different radials centered on the test item to collect pressure data in a range from 300 pounds per square inch, down to one psi. 

"By combining the velocity screens and transducers, we'll be able to pull a vast amount of information from this one test," said Ruth Ezell, Tech Director of Air to Surface Tests.
In subsequent weeks, the fiberboard collection bundles will be analyzed for fragment location (x, y and z coordinates). Each of the thousands of fragments will be removed from the bundles, cleaned, weighed and placed into a separate bag or envelope.