TB 1-1520-240-20-99
graphs 6 and 7 shall be annotated to read "CH-47-97-ASAM-10, One Time Inspection of ANVIS/HUD Pow-
er Supply, must be complied with prior to installation."
(1) Wholesale Stock. Report receipt of this TB in accordance with paragraph 14C( 1). Upon re-
ceipt of TB, all serviceable items (condition codes "A", "B", "C", "D", and "E" listed in paragraphs 6 and 7 lo-
cated in wholesale depot storage shall be placed in condition code "J" and tagged with a suspended tag/label
- material, DD Form 1575/DD Form 1575-1. Do not remove original condition tags. Report compliance with
(2) Retail Stock. Upon receipt of this TB, Commanders and others maintaining retail stock at
installation level and below shall contact the supported aviation unit to perform the inspection required by
materiel will be in accordance with paragraph 10. Report compliance with this message in accordance with
g. Components/ Parts in Work (Depot Level and Others). Items listed in paragraphs 6 and 7 in work
will not be issued until compliance with this TB is complete.
Task/Inspection Suspense Date. Within next 10 flight hours/ 14 days.
2.
Reporting Compliance Suspense Date. No later than 20 Oct 97 per paragraph 14.a of this TB.
3.
Summary of the Problem.
4.
a. The AN/AVS-7 heads up display provides operational symbology to pilots during aviator's night vi-
sion imaging system (ANVIS) operations by overlaying the symbology on the image provided by the ANVIS.
It was recently discovered that a component part power supply was changed by the vendor without approval,
causing the AN/AVS-7 to be susceptible to some power line transients. The AN/AVS-7 system will reset
when certain power spikes are received, causing the display to blank for a ten to fifteen second interval while
completing the power up sequence. Upon completion of the power up sequence the system will return to its
normal start up condition of full dim on the display and display page 1N.
c. The purpose of this TB is to:
(1) Require a one-time inspection of all AN/AVS-7 systems to verify installation of the correct
power supply component.
(2) Restrict flight operations with the AN/AVS-7 if an incorrect power supply component is
installed.
5.
End Items to be inspected. All CH-47D and MH-47D aircraft with the AN/AVS-7 installed.
Assembly Components to be Inspected.
6.
NOMENCLATURE
PART NUMBER
NATIONAL STOCK NUMBER
AN/AVS-7 SIGNAL DATA CON-
CV-4229(V)1/AVS-7(V)
5895-01361-8986
VERTER
7.
Parts to be Inspected.
NOMENCLATURE
PART NUMBER
NATIONAL STOCK NUMBER
CIRCUIT CARD ASSEMBLY
125118-001
(CCA) A5, POWER SUPPLY
MODULE
Inspection Procedures. Reference TM 11-5855-300-23&P for detailed instructions.
8.
a.
Remove the signal data converter from the aircraft in accordance with reference 13, section 2-17.
2