Military

G-1. Firing safety is paramount and every secondary independent check (verification) is designed to ensure rounds fired impact and detonate on the desired target. Failure to conduct secondary independent checks is the primary contributing factor to M109A6 Paladin firing incidents. Conducting procedurally correct crew drills can help prevent firing incidents from occurring. The most frequent types of firing incidents during Paladin live-fire operations that can be prevented by secondary independent checks are:

• Firing at load elevation.
• Degraded Operations (Appendix A) - the leadership must be proactive under degraded operations.
• Charge error.

Target location and verification of target location are important segments in fire mission processing as well. The POC has the responsibility to verify target location at the battery level. Targets must be physically plotted and checked to ensure they plot safely and do not violate any FSCM. The following techniques aid the FDC in ensuring that all target grids are cleared for safe engagement.

G-2. Safety is computed IAW the standards of FM 6-40 and can be derived from automated range safety. The FDO computes safety from the center of radius grid used in the move order. The safety data is valid for howitzers firing within a 750 meter radius of the surveyed grid. Using the range fan, the FDO maximizes his safety box by determining his own limits within an approved impact area. The left and right limits are input on the move order message format. The FDO determines minimum and maximum quadrants. The minimum and maximum quadrants and charge specific are sent to the howitzers by digital means on a SYS;PTM. The section chief enters the data into the AFCS. Min QE is entered into the AFCS. Maximum QE is input as maximum tube elevation. The FDO must specify charge using this technique. He must select the optimum charge to fire based on the tactical situation. Every mission sent to the howitzer must be checked, and the specified charge must be sent down to the howitzers. The POC must check and resolve intervening crests. (See Figure G-1.)

G-3. This technique requires the FDO to shrink the perimeter of the selected impact area 300 meters or IAW local range safety regulations (which ever is safest) to account for PEs. The minimum quadrant to fire is computed using the lowest optimum charge to the closest minimum range of the impact area. The POC transmits min QE to the howitzer using the SYS;PTM format, and the COS inputs min QE into the AFCS. The FDO does not send the howitzers a maximum QE. Not sending a maximum QE, allows the platoon greater flexibility to engage targets within their sectors and enables firing of different charges per mission. The FDO determines the left and right azimuth limits using the outermost edges of the shrunken impact area. The limits are sent to the howitzers on the movement order format. All data is safe as long as howitzers remain within a 750 meter radius of the occupation grid. (See Figure G-2.) The following are key points in unboxed safety:

• Min QE is computed using the lowest optimum charge.
• Left and right limits are sent on the movement order format.
• Multiple charges can be fired.
• Impact area is reduced by 300 meters or IAW local range safety regulations (which ever is safest) to allow for probable errors.
• Howitzer pairs work within a 750 meter radius.

G-4. Combat safety (see Figure G-3) is similar to unboxed safety with the following exceptions:

• The min QE is computed to the minimum range line (i.e., FLOT/brigade coordinated fire line (CFL)).
• Left and right limits are computed to the brigade boundaries and sent in the move order.
• The POC must check intervening crests.

G-5. Illumination safety (see Figure G-4) is similar to boxed safety and is computed using an approved safety box in an impact area. Computations are made in accordance with the procedures in FM 6-40. The FDO computes minimum and maximum quadrants. Maximum QE is computed using range to impact. The POC transmits the calculated data/safety "T" to the howitzers via SYS;PTM. The chief records the data but does not enter the safety "T" limits into the AFCS. The key points are:

• Similar to boxed safety.
• Illumination safety "T" is sent to guns via SYS;PTM.
• Howitzer section chief does not enter Safety "T" data into AFCS, but records the data.