WARNING: WHEN THE STATIC PORTS ARE COVERED, MAKE SURE THAT THE
_______ CONDITION IS VISIBLE FROM THE GROUND. FAILURE TO OBSERVE AND REMOVE COVERINGS OVER THE STATIC PORTS BEFORE FLIGHT MAY CAUSE LARGE ERRORS IN AIRSPEED SENSING AND ALTITUDE SENSING SIGNALS, WHICH MAY LEAD TO LOSS OF SAFE FLIGHT.
 (c) Seal the S1 static port on the lower left static probe.
 E. Mach Airspeed Warning Systems Test
 S 865-011
 WARNING: THE WARNING DEVICE (CLACKER) MUST NOT BE ENERGIZED FOR MORE
_______ THAN 5 MINUTES OR YOU CAN DAMAGE THE EQUIPMENT. PERMIT A MINIMUM OF 15 MINUTES BEFORE YOU ENERGIZE THE SYSTEM AGAIN.
 (1)  
Make sure the MACH WARN SYS-1 and -2, NO. 1 and NO. 2 AIR DATA and MACH AIRSPEED IND circuit breakers are closed on the P18 and P6 panel.

 S 865-013

 (2)
Push the MACH AIRSPEED WARNING TEST NO. 1 switch on the P5 panel.

 (a)  Make sure you hear the warning clacker.
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 (3)  S 865-014Release the test switch. (a) Make sure the clacker shuts off.
 (4)  S 865-015Do the previous steps again for the MACH AIRSPEED WARNING TEST NO. 2 switch.
 (5)  S 865-016Open the F/O's MACH AIRSPEED IND and MACH WARN SYSTEM-2 circuit breakers on the P6 panel.
 (6)  S 865-017Apply pressures to the captain's pitot-static system (mach airspeed warning system No. 1) as shown in Table 501.
 NOTE:____ You can use the pressure shown in Table 501 or the applicable altitude and CAS value.
 (a) (b)  At each test point, slowly decrease the static pressure until you are at the test altitude. 1) Do not go above the altitude value.Slowly increase the differential pressure until the warning clackers for the mach airspeed system come on.
 NOTE:____ Start from a value below the differential pressure tolerance.
 (c) (d)  1) Make sure the differential pressure is in tolerance.Decrease the differential pressure until the clackers go off. 1) Make sure the differential pressure is less than the differential pressure tolerance.Before you go to the next test altitude, do the step that follows: 1) Decrease the differential pressure to a value below the differential pressure tolerance of the next test altitude.
 NOTE:____ Use the flight deck instruments to cross check test instruments during this procedure.

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 Table 501. Mach Airspeed Warning System Test Limits

 ~.............................................................................. |ALT (FEET)| STATIC PRESSURE | PITOT PRESSURE | DIFF PRESSURE | CAS KNOTS | | (REF) | IN Hg ABSOLUTE | IN Hg ABSOLUTE | IN Hg ABSOLUTE | (REF) | ................................................................................ | 5,000 | 24.896 | 30.805 - 30.954 | 5.909 - 6.058 | 340.0 - 344.0| | 25,000 | 11.104 | 17.010 - 17.162 | 5.906 - 6.058 | 340.0 - 344.0| | 35,000 | 7.041 | 10.950 - 11.018 | 3.909 - 3.977 | 279.5 - 281.8| 2..........….................….................…................…..............1
 S 865-018
 (7)  
Open the captain's MACH AIRSPEED IND and MACH WARN SYSTEM-1 circuit breakers on the panel P18.

 S 865-019

 (8)  
Close the F/O's MACH AIRSPEED IND and MACH WARN SYSTEM-2 circuit breakers.

 S 865-020

 (9)  
Apply pressures to the first officer's pitot-static system (mach airspeed warning system No. 2) as shown in Table 501.

 NOTE: You can use the pressure shown in Table 501 or the applicable
____
 Altitude and CAS value.

 (a)  
At each test point, slowly decrease the static pressure until you are at the test altitude. 1) Do not go above the altitude value.

 (b)  
Slowly increase the differential pressure until the warning clackers for the mach airspeed system come on.