# TM 1-70-23AW-2

TECHNICAL MANUAL
AIRWORTHINESS LIMITATIONS MANUAL FOR

SIKORSKY MODEL S-70 FOREIGN MILITARY SALES AND COMMERCIAL HELICOPTERS

OPERATING UNDER FEDERAL AVIATION ADMINISTRATION CERTIFICATION

THIS MANUAL SUPERSEDES TM 1-70-23AW-2 DATED 1 FEBRUARY 1999, WITH CHANGE INFORMATION. CHANGE 3- 15 APRIL 2012 HAS BEEN INCORPORATED IN THIS ISSUE AND MAKES THIS A COMPLETE MANUAL.

WARN NG:
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MIS DOCUMENT, CR AN EMBODIMENT OF IT IN ANY MEDIA, DISCLOSES INFORMATION WHICH IS PROPRIETARY. IS THE PROPERTY OF SIKORSKY AIRCRAFT CORPORATION AND/OR ITS SUBSIDIARIES, IS AN UNPUBLISHED WORK PROTECTED UNDER APPLICABLE COPYRIGHT LAWS. AND IS DELIVERED ON THE EXPRESS CONDITION THAT IT IS NOT TO BE USED, DISCLOSED, REPRODUCED, IN WHOLE OR IN PART (INCLUDING RE. PRODUCTION AS A DERIVATIVE WORK), OR USED FOR MANUFACTURE FOR ANYONE OTHER THAN SIKORSKY AIRCRAFT CORPORATION AND/OR ITS SUBSIDIARIES WITHOUT ITS WRITTEN CONSENT, AND THAT NO RIGHT IS GRANTED TO DISCLOSE OR SO USE ANY INFORMATION CONTAINED HEREIN, ALL RIGHTS RESERVED. ANY ACT IN VIOLATION OF APPUCABLE LAW MAY RESULT IN CIVIL AND CRIMINAL PENALTIES.EXPORT WARNING: THESE COMMODITIES, TECHNICAL DATA OR SOFTWARE ARE SUBJECT TO THE EXPORT CONTROL OF EITHER THE INTERNATIONAL TRAFFIC IN ARMS REGULATIONS (ITAR) OR THE EXPORT ADMINISTRATION REGULATIONS (EAR) AND CANNOT BE E XPORTED WITHOUT THEPRIOR AUTHORIZATION OF EITHER THE DEPARTMENT OF STATE OR THE DEPARTMENT OF COMMERCE. THE TERM "EXPORT' INCLUDES DISCLOSURE AND/OR PROVISION OF ACCESS TO COMMODITIES, TECHNICAL DATA OR SOFPNARE TO OR BY FOREIGN NATIONALS (WHETHER LOCATED IN THE UNITED STATES OR ABROAD). THIS REQUIREMENT ALSO APPLIES ro FOREIGN NATIONAL EMPLOYEES OE U.S. COMPANIES AND THEIR FOREIGN SUBSIDIARIES.

SIKORSKY AIRCRAFT CORPORATION - 24 MARCH 1997 CHANGE 3- 15 APRIL 2012 SIKORSKY AIRCRAFT CORPORATION

24 MARCH 1997

### TM 1-70-23AW-2



### TECHNICAL MANUAL AIRWORTHINESS LIMITATIONS MANUAL

FOR SIKORSKY MODEL S-70 FOREIGN MILITARY SALES AND COMMERCIAL HELICOPTERS

OPERATING UNDER FEDERAL AVIATION ADMINISTRATION CERTIFICATION

TABLE OF CONTENTS

Change 3a. Determine number of hours on component.
b. Determine the percentage of life used using the following equation: 

### No. of hrs on component = % of life used Life Limit where the life limit is from the aircraft the component was removed from.

c. Multiply the "% of life used" calculated above by the "Life Limit" of the part for the new model aircraft to determine the equivalent number of component hours consumed on the new aircraft. Two sample calculations are presented as follows: EXAMPLE A: Life limits provided by Sikorsky Aircraft: Life Limit Aircraft 10000 Hours A 7000 Hours
I 5000 hours were consumed while the component was on aircraft A. (Step 1)

50% of the component life has been consumed. 0.5 x 7000 = 3500 Hours (Step 3)3500 equivalent hours have been consumed on aircraft B and the life limit of the component on aircraft B remains at 7000 hours. EXAMPLE B: Life Limits Provided By Sikorsky Aircraft: Life Limit 3000 Hours 5000 Hours Aircraft 

### 5000 Hours = 0.5 = 50% (Step 2) 10000 Hours PARA 1.1 TM 1-70-23AW-2
1.1.3 Component Life Prorating.

NOTE Many components on the S-70A aircraft are common to several other models which have different component life limits due to different usage and flight loads. It is not recommended to transferany components between aircraft models. If the history of an aircraft component is unknown, that component CAN NOT be used on an S-70A aircraft.However, if an aircraft component is going to be used on a different aircraft model with different life limits and a known part history, prorating will have to be used to determine the equivalent life consumed for the new aircraft model the part is to be installed on. The procedure below can be applied to any life-limited component transferred between aircraft models with differentlife limits. Part transfer cannot be performed if the component has an "Unlimited" or"On Condition" life limit on one aircraft model and a "Limited Life" or"On Condition" life limit on another aircraft model, unless a methodology to conservatively estimate the component life is determined and approved by Sikorsky Aircraft. To prorate the component lives, the life limits for both the aircraft the part was removed from and the aircraft the part is being installed on will need to be known. Contact Sikorsky Aircraft at I -800-WINGED-S (1-800-9415-4337) or v i a e-mail a t sikorskywcstOsikorsky.com , in order to determine the appropriate life limits for aircraft models.The percentage of life is used to determine the component life consumed on the new aircraft. The new aircraft's component life limit is not changed with this procedure.

Change 3 1-25Table 2. Aircraft Prorate Calculation

1) Aircraft component was removed from: 2) Recommended retirement time on old aircraft: 3) Original time since new (Step I): 4) % of life used (Line 3/Line 2) (Step 2): 5) S-70A recommended retirement time: 6) Equivalent time used on S-70A (Line 4 x Line 5) (Step 3): 1200 hours were consumed while the component was on aircraft C. (Step I) 1200 Hours = 0.4 = 40% (Step 2) 3000 Hours 40% of the component life has been consumed. 0.4 x 5000 = 2000 Hours (Step 3)2000 equivalent hours have been consumed on aircraft D and the life limit of the component on aircraft D remains at 5000 hours. The calculated information shall then be documented in the REASON FOR REMOVAL section of the components log card in the following form:
A/C removed from: Original time since new:
Calculated % time used: Equivalent time used on S-70A: TM 1-70-23AW-2 PARA 1.1



# I The calculated information shall then be documented in the REASON FOR REMOVAL section of the components log card in the following form: Original time since new (Line 3): Calculated % time used (Line 4): Equivalent time used on S-70A (Line 6): A/C removed from 

### (Line 1):

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