MIL-STD-2088-SUP-2 Bomb Rack Unit BRU, Single Store, AircraftThis standard establishes the general guidelines and criteria for the design and development of a single store bomb rack unit BRU for carriage and release of airborne stores excluding air-to-air missiles from fixed wing and rotary wing aircraft using a single suspension point or suspension points spaced at 14 or 30 inches. This standard addresses detailed requirements for gravity non-ejected, pyrotechnic, hydraulic, and pneumatic powered BRUs. Mechanical aircraft armament interoperable interfaces are incorporated to enhance cross utilization and servicing capabilities between military aircraft and aircraft stores see 3.1 of all services of the Department of Defense DoD and North Atlantic Treaty Organization NATO nations.

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MIL-STD-2088B

With both the electrical and mechanical interrupts removed, the safety interlock shall be in its ARMED position. With the electrical interrupt in place and the mechanical interrupt removed, the safety interlock shall be in its GROUND position. The BRU shall provide both local and remote status indication of the safety interlock mechanism. Local status indication shall provide visual indication of the safety interlock mechanism's position. The position indicator shall be mechanically linked to the safety interlock and be visible from a distance of 15 feet (line of sight permitting) during daylight hours. The safety interlock shall only be capable of being set to the SAFE position with both store supports fully latched. The BRU shall provide discrete signals to remotely indicate the status of the safety interlock to the aircraft or aircraft systems monitoring equipment. The safety interlock status shall be sensed such that no single sensor failure shall provide the aircraft with an erroneous SAFE status.

5.1.6.2 Interrupt removal. During ground operations or during aircraft in-flight preparations for store release, the first event shall remove the electrical interrupt, and the second event shall remove the mechanical interrupt from the BRU allowing store support latch release operation. The first event shall not be permitted to occur unless the mechanical interrupt is in place. If sufficient energy is present on the electrical control circuit when the electrical interrupt is removed, initiation of the BRU store release may occur. If store release is initiated while the mechanical interrupt is still in place, a "Lock-Shut-Firing" of the BRU shall result. The mechanical interrupt shall be designed so that it cannot be removed by manual or automated means while the BRU is in the "Lock-Shut-Fire" state. The second event shall not be permitted to occur until time has elapsed, with the electrical interrupt removed, to permit a BRU

"Lock-Shut-Firing" if release energy is present.

5.1.6.3 Alternative interrupt removal. As an alternative, the release control circuit may be monitored for the presence of electrical energy to initiate the release of the BRU's stored energy. If insufficient electrical energy is present to cause the release of energy, then the electrical and mechanical interrupts may be removed simultaneously. To ensure the accuracy and integrity of the voltage monitoring system, it shall be verified against other electrical circuit energy levels that are independently verified.

5.1.6.4 Safety interlock ground operation. During ground loading and unloading

operations, the safety interlock mechanical interrupt shall be removed without the removal of the electrical interrupt. To ensure maximum protection with the mechanical interrupt removed while the electrical interrupt is in place, the electrical interrupt shall be prevented from being removed until the mechanical interrupt is replaced (SAFE position).

5.1.6.5 Safety interlock control. The safety interlock shall be designed for either manual or remote operation. Remote operation shall be controlled through the safety interlock drive mechanism using aircraft power and commands. The safety interlock mechanism shall be capable of being latched in the GROUND position for store loading or downloading operations. The safety interlock shall not be latched in the ARMED position and shall return to its SAFE position when power is removed from the drive mechanism (provided the store supports are in