TM 1-1520-238-10 4-10 Change 9 Section  II.    ARMAMENT 4.7   AUTHORIZED ARMAMENT CONFIGURATIONS. For authorized configurations, refer to figure 7-18 or figure 7A-18 . 4.8   AREA WEAPON SYSTEM 30MM, M-230E1. WARNING In the event of IHADSS failure with gun selected, the gun will be commanded to the fixed forward position. Once in this position, the gun can still be fired with- out having to re–action the gun. Prior to initiating AWS FD/LS check, en- sure the pilot ground override (PLT/GND ORIDE)  switch  is  in  the  OFF  position. Failure to perform this action may result in  uncommanded  gun  turret  slewing  or uncommanded gun firing during a AWS FD/LS manual abort. CAUTION If  ECP  1206  (Mechanical  Gun  Stops)  is installed,  but  not  ECP  1251  (Electronic Gun  Stops),  the  M230E1  AWS  may  be used with the following restrictions: · If  external  tanks  are  installed,  limit AWS azimuth travel to 45 degrees. · If external tanks are not installed, limit AWS azimuth travel to 70 degrees. If both ECPs are installed, the AWS is not restricted   when   external   tanks   are mounted. If neither ECP is installed, the AWS is re- stricted  from  use  when  external  tanks are mounted. The M-230E1, 30mm gun (fig 4-5) is a single barrel, exter- nally  powered,  chain  drive  weapon  using  M788/789  or ADEN/DEFA  type  ammunition.  The  30mm  gun  is mounted in a hydraulically driven turret capable of slewing the gun 100° or 86° / left or right of the he- licopter centerline and up 11° to 60° down. In the event of loss of hydraulics, the turret will lock in the current azimuth position and the gun will return to the elevation stow posi- tion of 11° up. The rate of fire is set for 600 to 650 rounds per minute. The maximum capacity of the linkless storage subsystem is 1200 rounds. The FCC limits the fire control solution to a maximum range of 4000 meters. The maxi- mum range of the 30mm gun is approximately 4000 me- ters. The gun duty cycle is as follows: WARNING Failure  to  adhere  to  the  published  gun duty  cycle  may  result  in  a  catastrophic failure, loss of aircraft, injury or death. · Six 50 round bursts with 5 seconds between bursts followed by a 10 minute cooling period. · For BURST LIMITER settings other than 50, the duty cycle can generalized as no more than 300 rounds fired within 60 seconds before allowing the gun to cool for 10 minutes, after which the cycle may be repeated. 4.8.1   AWS Dynamic Harmonization / . Dy- namic harmonization is the capability of the flight crew to apply an in flight boresight correction procedure. Dynamic harmonization corrects for AWS system variations and fir- ing characteristics for different aircraft and AWS combina- tions. The procedure involves live-fire of the 30mm gun to fine tune the system in addition to the CBHK static bore- sight. Performance of dynamic harmonization is not a require- ment but a crews option. This procedure is not intended to replace the CBHK static boresight or proper AWS mainte- nance. Any modification of boresight correctors must be entered in the aircraft logbook. Correctors remain in the FCC until changed via the boresight procedures.