Use of Statistical Tools to Improve Modeling and Simulation of Store Separation
Abstract
The MK-82 Joint Direct Attack Munition (GBU-38) is cleared for carriage and employment for the entire F/A-18C aircraft flight envelop from the BRU-55 Canted Vertical Ejector Rack (CVER). The GBU-38 was certified for carriage and release through a series of flight tests. For the first flight where the store was released form the BRU-55, the wind tunnel Captive Trajectory System (CTS) data, as well as NAVAIR and Boeing pre-flight predictions, showed no resemblance to the flight test results. The original NAVSEP and Boeing predictions considerably underpredicted the roll rate, and had the yaw rates in the opposite direction from the flight test telemetry results. Since the wind tunnel CTS trajectories had the same errors, the simulations obviously were missing an important feature of the trajectories. For the flight from the CVER there was a spike in the rolling moment during the ejector stroke. This roll spike was attributed to the misalignment between the ejector force line of action and the store c.g. A statistical approach was used to modify the ejector force characteristics to best match the flight test data. This modification gave an excellent match with the flight test results for all the succeeding test points.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2004
- Accession Number
- ADA468593
Entities
People
- A. Cenko
- A. Piranian
- J. Rupert
Organizations
- Naval Air Systems Command