51FWI21-107 governs procedures and responsibilities for using the Hush House noise sound suppresser during installed engine runs.
View 51FWI21-107 on armypubs.army.mil
It covers aircraft delivery, configuration, staffing, engine-run approvals, emergency precautions, fire suppression, and post-run inspections. It requires compliance with applicable checklists, technical orders, local directives, and specified safety procedures.
A minimum of four people will be required on all installed engine operations. (paragraph 2)
Installed engine runs will be accomplished by the requesting organization and will furnish ground restraints, an engine operator, a ground supervisor, and a fireguard. (paragraph 2)
If the HH fire suppression system is not operational, the Fire Department must be present during all engine run operations, IAW OSANABI 32-2001, Fire Prevention Program. (paragraph 2)
Open fuel cell maintenance is not permitted inside the HH. (paragraph 2)
Upon completion of aircraft functional checks, the owning organization using the HH will remove the aircraft from the HH as soon as possible and perform an engine Foreign Object Damage (FOD) inspection. (paragraph 2)