Correction Procedures

TB 1-1520-251-20-01

NOTE

HPSM #1 S/N 8 and 37 have been previously reworked to the correct

configurations.

(1) If either HPSM #1 is numbered 1 through 38 (less S/N 8 and 37), or HPSM #2 is numbered

1 through 37, remove and replace in accordance with paragraph 9.c. Contact the logistical point of contact

in paragraph 16.b to coordinate replacement of the HPSM.

(2) If both HPSM #1 is not numbered 1 through 38 (less S/N 8 and 37), and HPSM #2 is not num-

bered 1 through 37, proceed to paragraph 8.b.

b. Inspect the aircraft historical logbook, DA Form 2408--13, DA Form 2408--15, and DA Form

2408--5--1 (Generators) to verifiy the either Apache retrofit service notice (RSN) 97D155R2 or 97D155R3

have been applied to the aircraft generators.

(1) If the aircraft records verify that either RSN has been applied, proceed to paragraph 8.c.

(2) If the aircraft records do not verify that Apache RSN 97D155R2 or 97D155R3 have been ap-

plied, contact logistical point of contact listed in paragraph 16.b for further guidance.

c. After verification that HPSM #1 is not numbered 1 through 38 (less S/N 8 and 37), HPSM #2 is not

numbered 1 throught 37, and the generator drive modification has been verified, proceed to paragraph 9.

d. Inspect retail repair parts stockage to determine is adapter, spline, P/N 1593588--9, NSN

3040--01--382--2814 is on hand and if it is yellow--green in color. If this part is on hand and is yellow--green

in color, it is Torlon and is not to be used on the AH--64D. Proceed to paragraph 10 for disposition instructions.

Correction Procedures.

a. After verifying that AH-64D aircraft have received the generator drive modifications and suspect

HPSMs have been replaced, change the condition status symbol of the cited aircraft to a circled red //x//.

The circled red //x// entry shall state "Aircraft restricted to day VFR flight operations in accordance with TB

1-1520-251-20-01." While the aircraft is on a circled red //x//, it may be reported as fully mission capable

(FMC).

b. For AH-64D aircraft that have not received both the generator drive modifications and have not re-

placed suspect HPSMs as required, clear the red dash //--// and change the condition status symbol of the

cited aircraft to a red //x//. The red //x// entry shall state "Aircraft grounded in accordance with TB

1-1520-251-20-01. Aircraft status may be changed to a circled red //x// per paragraph 9.a above, when both

the generator drive modifications and suspect HPSMs have been replaced." Aircraft in red //x// status will

be maintained in flyable storage with ground run-ups authorized.

Removal and replacement procedures for suspect HPSMs per reference 13.e:

(1) Perform IETM task module, switching high power, No. 1--

(a) System: Electrical power subsystem

(b) Subsystem: Power distribution system

(d) IETM element: Module, switching, high power No. 1

(e) Remove and install

(2) Perform IETM task module, switching high power, No. 2--

(a) System: Electrical power subsystem

(b) Subsystem: Power distribution system

(d) IETM element: Module, switching, high power No. 2