# Boeing Alert Requirements Bulletin 737-55A1104 RB: No revision named

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- Title as filed: RB-737-55A1104-00--
- Pages: 43
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## Text

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### Page 1

Commercial 
Airplanes
737
Requirements Bulletin
ALERT
Number: 737-55A1104 RB
Original Issue: June 12, 2025
ATA System: 5510
SUBJECT: STABILIZERS - Horizontal Stabilizer - Pivot Hinge and Jackscrew Freeplay Inspection
EXPORT CONTROLLED - This technology or software is subject to the U.S. Export Administration Regulations
(EAR), (15 C.F.R. Parts 730-774). No authorization from the U.S. Department of Commerce is required for
export, re-export, in-country transfer, or access EXCEPT to country group E:1 or E:2 countries/persons per
Supp.1 to Part 740 of the EAR.
9E991ECCN:
Copyright © 2025 The Boeing Company
Treatment of this document and its content is governed by contract with Boeing. Rights to use this document
are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The
Boeing Company.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner,
BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and
Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in
connection with this document unless provided in writing by Boeing.
Original Issue: June 12, 2025
737-55A1104 RB
1 of 43
7.0

### Page 2

Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
2 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT
BLANK PAGE

### Page 3

Table of Contents
1. EFFECTIVITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
A. Airplanes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
B. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2. CONCURRENT REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3. COMPLIANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4. APPROVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5. ACCOMPLISHMENT INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
A. General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
B. Work Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
FIGURE 1: LEFT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
FIGURE 2: RIGHT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
FIGURE 3: HORIZONTAL STABILIZER JACKSCREW - FREEPLAY MEASUREMENT PROCEDURE. 36
FIGURE 4: HORIZONTAL STABILIZER PIVOT HINGES AND THE JACKSCREW - TOTAL FREEPLAY
MEASUREMENT PROCEDURE VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
APPENDIX H: FREEPLAY VALUE LIMITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
3 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 4

Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
4 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT
BLANK PAGE

### Page 5

Commercial 
Airplanes
737
Requirements Bulletin
ALERT
Number: 737-55A1104 RB
Original Issue: June 12, 2025
ATA System: 5510
SUBJECT: STABILIZERS - Horizontal Stabilizer - Pivot Hinge and Jackscrew Freeplay Inspection
THIS DOCUMENT IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN
EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS DOCUMENT TO THE NEW
OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE NEW OWNER.
THIS IS AN ENHANCED REQUIRED FOR COMPLIANCE DOCUMENT. THE BOEING PROCESSES USED
TO CREATE THE SERVICE BULLETIN (SB) AND THE REQUIREMENTS BULLETIN (RB) ENSURE THAT
THE INFORMATION BETWEEN "RC START" AND "RC END" IN THE SB ARE IDENTICAL TO THE
INFORMATION IN THE SAME SECTIONS (COMPLIANCE, WORK INSTRUCTIONS…) OF THE RB WHICH
THE SB REFERS TO AS THE RELATED DOCUMENT.
1. Effectivity
A. Airplanes
This bulletin is applicable to 737-600, 737-700, 737-700C, 737-800, 737-900, 737-900ER
Airplane(s), line number(s) 1-2598, 2600-2721, 2723-2813, 2815-2930, 2932-3068, 3070-3323,
3325-3425, 3427-3521, 3523-3611, 3613-3701, 3703-3791, 3793-3878, 3880-3915, 3917-3968,
3970-4013, 4015-4054, 4056-4098, 4100-4140, 4142-4180, 4182-4218, 4220-4255, 4257-4293,
4295-4330, 4332-4365, 4367-4398, 4400-4444, 4446-4480, 4482-4546, 4548-4608, 4610-4672,
4674-4727, 4729-4767, 4769-4812, 4814-4858, 4860-4897, 4899-4937, 4939-4977, 4979-5019,
5021-5057, 5059-5097, 5099-5137, 5139-5177, 5179-5217, 5219-5261, 5263-5297, 5299-5337,
5339-5367, 5369-5397, 5399-5427, 5429-5452, 5454-5457, 5459-5477, 5479-5509, 5511-5541,
5543-5566, 5568-5586, 5588-5601, 5603-5622, 5624-5655, 5657-5667, 5669-5679, 5681-5711,
5713-5727, 5729-5739, 5741-5764, 5766-5787, 5789-5795, 5797-5822, 5824-5850, 5853-5879,
5881-5901, 5904-5935, 5937-5947, 5949-5962, 5964-5991, 5994-6019, 6021-6033, 6035-6047,
6049-6073, 6075, 6077-6103, 6105-6113, 6115-6131, 6133-6153, 6155-6159, 6161-6187,
6190-6215, 6217-6221, 6223-6243, 6245-6249, 6251-6271, 6274-6289, 6291-6299, 6301-6307,
6309-6325, 6327, 6329-6343, 6345-6355, 6357-6359, 6361-6371, 6373-6383, 6386-6395,
6397-6407, 6409-6411, 6413-6419, 6421-6429, 6431-6439, 6442-6447, 6449-6455, 6457-6463,
6465-6467, 6469-6471, 6473-6480, 6482-6489, 6491, 6493-6498, 6500-6507, 6509-6514,
6516-6520, 6522-6527, 6529-6531, 6533-6534, 6536-6541, 6543-6547, 6549-6554, 6556-6559,
6561, 6563-6568, 6570-6574, 6576-6581, 6583-6588, 6590-6593, 6596-6597, 6599-6602,
6604-6606, 6608-6611, 6613-6615, 6617-6620, 6622, 6624, 6626-6629, 6631-6633, 6635-6638,
6640-6642, 6644-6647, 6649-6651, 6653-6656, 6659-6660, 6662-6665, 6667-6671, 6673-6676,
6678-6680, 6682-6685, 6688-6689, 6691-6694, 6696-6698, 6700-6703, 6705-6707, 6709-6712,
6714-6716, 6718-6719, 6721, 6723-6725, 6727-6730, 6732-6734, 6736-6739, 6741-6743,
6745-6748, 6751-6752, 6754-6757, 6759-6761, 6763-6766, 6768-6770, 6772-6775, 6777-6779,
6781-6782, 6786-6788, 6790-6791, 6793, 6795, 6797, 6799-6802, 6804, 6806, 6808-6809, 6811,
6813, 6815, 6817-6818, 6820, 6822-6824, 6826-6827, 6829, 6831-6833, 6835-6836, 6838, 6840,
6842, 6844-6845, 6847, 6849, 6851, 6853-6854, 6856-6858, 6860, 6862-6863, 6865, 6867,
6869-6871, 6873-6874, 6878-6880, 6882-6883, 6885, 6887-6889, 6891-6892, 6894, 6896, 6898,
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
5 of 43

### Page 6

6900-6903, 6905, 6907, 6910, 6912-6914, 6916, 6918-6919, 6921, 6923-6925, 6927-6928, 6930,
6932-6934, 6936-6937, 6939, 6943, 6945-6948, 6950, 6952, 6954-6955, 6957-6959, 6961-6962,
6964, 6966-6967, 6969, 6971-6972, 6977, 6979, 6981-6982, 6984, 6986-6987, 6989, 6992, 6994,
6996-6997, 6999, 7001-7002, 7007, 7009, 7011-7012, 7014, 7016-7017, 7019, 7021-7022, 7024,
7026, 7029, 7031-7032, 7034, 7036-7037, 7039, 7041, 7046-7047, 7049, 7051-7052, 7054,
7056-7057, 7059, 7061, 7063, 7066-7067, 7069, 7071-7072, 7076, 7078, 7081-7082, 7084,
7086-7087, 7089, 7091-7092, 7094, 7097, 7099, 7101-7102, 7104, 7106-7107, 7109, 7112,
7116-7117, 7119, 7121-7122, 7124, 7126-7127, 7129, 7131, 7134, 7136-7137, 7139, 7141-7142,
7146, 7149, 7151-7152, 7154, 7156-7157, 7159, 7161-7162, 7164, 7167, 7169, 7171-7172, 7174,
7176-7177, 7179, 7182, 7187, 7189, 7191, 7194, 7197, 7199, 7202, 7204, 7206, 7209, 7212,
7214, 7217, 7221, 7224, 7227, 7229, 7232, 7234-7235, 7239, 7242, 7244, 7247, 7249, 7251,
7257, 7259, 7262, 7264, 7266, 7269, 7272, 7274, 7277, 7279-7280, 7284, 7287, 7292, 7294,
7297, 7299, 7302, 7304, 7307, 7309, 7312, 7314, 7317, 7319, 7322, 7327, 7329, 7332, 7334,
7337, 7339, 7342, 7344, 7347, 7349, 7352, 7354, 7357, 7362, 7364, 7367, 7369, 7372, 7374,
7377, 7379, 7382, 7387, 7397, 7402, 7407, 7412, 7417, 7422, 7432, 7437, 7442, 7447, 7452,
7457, 7467, 7472, 7477, 7482, 7487, 7492, 7502, 7507, 7512, 7517, 7522, 7527, 7537, 7547,
7552, 7557, 7562, 7572, 7577, 7582, 7587, 7592, 7597, 8592, 9103, 9274, 9430-99999 in 1
Group(s). Where the effectivity is presented with hyphens between line numbers, the airplane
applicability means "through" and "inclusive", e.g. line numbers 1-9 means line numbers 1 through
9 inclusive.
The Variable Numbers and Group Information for the applicable airplanes is given below.
NOTE: Airplanes listed in the effectivity of this bulletin can be classified into one of the two
configurations specified in the group-configuration description table to determine initial
inspection threshold in accordance with this bulletin. Operators must determine airplane
configuration based on the definition given. Configuration is based on if the airplane has
previously accomplished any of the accepted freeplay measurement procedures of the
horizontal stabilizer pivot hinges and the jackscrew before the original issue date of
Requirements Bulletin 737-55A1104 RB, AND freeplay values are within Level 1 limits
specified in APPENDIX H or corrective action was taken to bring freeplay values to within
the Level 1 limits.
The Boeing Company documents that follow are considered accepted freeplay
measurement procedures of the horizontal stabilizer pivot hinges and the jackscrew:
MOM-MOM-22-0187-01B dated April 6, 2022,
MOM-MOM-22-0187-01B(R1) dated May 27, 2022,
737-600/700/800/900 AMM TR 27-09-91/601 dated July-2022,
737-600/700/800/900 AMM Task 27-09-91-200-804 October-2022 revision,
737-600/700/800/900 AMM Task 27-09-91-200-804 June-2023 revision,
737-600/700/800/900 AMM Task 27-09-91-200-804 October-2023 revision.
NOTE: The Variable Number table below includes affected airplanes available as of the issue
date of this bulletin. Affected airplane Variable Numbers added to MyBoeingFleet.com
after the issue date of this bulletin will be shown using the Maintenance Performance
Toolbox EFFECTIVITY search function result.
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
6 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 7

DESCRIPTIONCONFIGURATIONGROUP
737-600, 737-700, 737-700C, 737-800, 737-900, 737-900ER
Airplanes.
-1
Airplanes that have previously accomplished any of the accepted
freeplay measurement procedures of the horizontal stabilizer pivot
hinges and the jackscrew before the original issue date of
Requirements Bulletin 737-55A1104 RB. (The accepted procedures
ensure that the freeplay values are within Level 1 limits as specified
in APPENDIX H of this bulletin.)
1
Airplanes that have not accomplished any of the accepted freeplay
measurement procedures of the horizontal stabilizer pivot hinges and
the jackscrew before the original issue date of Requirements Bulletin
737-55A1104 RB.
2
Airplane Models:
737-600, 737-700, 737-700C, 737-800, 737-900, 737-900ER
GroupVariable Number
1YA001 - YA099
1YA101 - YA199
1YA201 - YA211
1YA221
1YA231 - YA242
1YA251 - YA256
1YA271 - YA272
1YA291
1YA301 - YA302
1YA311 - YA314
1YA321 - YA323
1YA336 - YA345
1YA351
1YA356 - YA357
1YA366 - YA367
1YA371 - YA377
1YA501 - YA536
1YA541 - YA552
GroupVariable Number
1YA571 - YA578
1YA601 - YA615
1YA621 - YA622
1YA626 - YA631
1YA635 - YA636
1YA641 - YA642
1YA645 - YA650
1YA656 - YA659
1YA666 - YA667
1YA671 - YA672
1YA681 - YA691
1YA701 - YA710
1YA721 - YA722
1YA731 - YA734
1YA751 - YA756
1YA801 - YA803
1YA809
1YA811 - YA814
GroupVariable Number
1YA831 - YA835
1YA841 - YA862
1YA881 - YA882
1YA891 - YA892
1YA961 - YA978
1YB001 - YB006
1YB101 - YB132
1YB151 - YB153
1YB156 - YB158
1YB161 - YB164
1YB171 - YB172
1YB181 - YB184
1YB201 - YB208
1YB271
1YB276
1YB301 - YB310
1YB371 - YB392
1YB501 - YB502
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
7 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 8

GroupVariable Number
1YB521 - YB526
1YB541 - YB544
1YB551
1YB561 - YB598
1YB601 - YB636
1YB651
1YB656
1YB671 - YB672
1YB851 - YB863
1YB871 - YB874
1YB881 - YB893
1YB901 - YB903
1YB911
1YB961 - YB975
1YB981
1YB986 - YB998
1YC001 - YC030
1YC051 - YC084
1YC091 - YC095
1YC101 - YC104
1YC111 - YC113
1YC121
1YC126 - YC127
1YC136 - YC141
1YC146 - YC147
1YC151 - YC156
1YC166 - YC171
1YC176 - YC179
1YC186 - YC190
1YC201 - YC203
1YC206 - YC207
1YC301 - YC305
1YC321 - YC387
GroupVariable Number
1YC391 - YC394
1YC396
1YC401 - YC417
1YC421 - YC422
1YC426 - YC428
1YC436 - YC439
1YC441 - YC448
1YC451 - YC455
1YC459
1YC461 - YC467
1YC471 - YC499
1YC501 - YC526
1YC571 - YC583
1YC587 - YC589
1YC591 - YC593
1YC601 - YC655
1YC681 - YC696
1YC701 - YC715
1YC720 - YC725
1YC727 - YC752
1YC761 - YC770
1YC781 - YC793
1YC801 - YC892
1YC901 - YC907
1YC921 - YC922
1YC931 - YC932
1YC941 - YC951
1YC971 - YC978
1YC981 - YC983
1YD001 - YD007
1YD021 - YD025
1YD041 - YD057
1YD081 - YD084
GroupVariable Number
1YD101 - YD117
1YD121 - YD126
1YD151 - YD159
1YD171 - YD172
1YD201 - YD203
1YD206 - YD209
1YD216 - YD219
1YD251 - YD254
1YD256 - YD257
1YD261
1YD301 - YD334
1YD391
1YD401 - YD410
1YD412 - YD424
1YD481 - YD485
1YD491 - YD499
1YD501 - YD512
1YD531 - YD535
1YD541 - YD547
1YD561 - YD564
1YD571 - YD572
1YD591 - YD595
1YD601 - YD612
1YD651 - YD655
1YE001 - YE020
1YE051
1YE101 - YE109
1YE151 - YE157
1YE171 - YE172
1YE201 - YE206
1YE301 - YE305
1YE321 - YE326
1YE371 - YE383
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
8 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 9

GroupVariable Number
1YF001 - YF011
1YF021 - YF049
1YF051 - YF080
1YF086 - YF087
1YF106 - YF107
1YF111 - YF114
1YF116 - YF119
1YF121 - YF132
1YF176 - YF178
1YF191 - YF192
1YF201 - YF276
1YF401 - YF402
1YF431 - YF432
1YF436 - YF437
1YF441 - YF442
1YF451 - YF460
1YF501 - YF599
1YF601 - YF685
1YF691 - YF695
1YF701 - YF707
1YF801 - YF805
1YF831 - YF832
1YF836 - YF838
1YF871 - YF872
1YF901 - YF905
1YF921 - YF928
1YF951 - YF954
1YG001 - YG044
1YG061 - YG064
1YG066 - YG089
1YG091 - YG099
1YG101 - YG104
1YG111 - YG114
GroupVariable Number
1YG116 - YG149
1YG151 - YG152
1YG201 - YG205
1YG211 - YG214
1YG221 - YG224
1YG251 - YG252
1YG501 - YG517
1YG601 - YG602
1YG701
1YG711
1YG721 - YG722
1YH001 - YH012
1YH031 - YH055
1YH071 - YH080
1YH101 - YH132
1YH201 - YH202
1YH206 - YH207
1YH301 - YH307
1YH321 - YH322
1YH501 - YH542
1YH551 - YH594
1YH601 - YH606
1YH611 - YH620
1YH631 - YH632
1YH636 - YH637
1YH641
1YH681 - YH686
1YH701 - YH755
1YH801 - YH899
1YH901 - YH908
1YH911 - YH915
1YH951 - YH952
1YJ001 - YJ013
GroupVariable Number
1YJ021
1YJ471 - YJ480
1YJ501 - YJ517
1YJ531 - YJ579
1YJ591 - YJ599
1YJ631 - YJ632
1YJ671 - YJ694
1YJ801 - YJ867
1YJ871 - YJ880
1YJ901 - YJ904
1YJ908 - YJ929
1YJ931 - YJ937
1YJ941 - YJ956
1YJ961
1YJ976 - YJ977
1YK001 - YK007
1YK101 - YK104
1YK111 - YK112
1YK121 - YK122
1YK131 - YK133
1YK136 - YK139
1YK141 - YK142
1YK146 - YK148
1YK151 - YK154
1YK161 - YK167
1YK171
1YK176 - YK177
1YK186
1YK191
1YK196
1YK201 - YK202
1YK301 - YK314
1YK321 - YK340
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
9 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 10

GroupVariable Number
1YK361 - YK378
1YK401 - YK406
1YK426 - YK427
1YK431 - YK450
1YK456 - YK467
1YK471 - YK473
1YK476
1YK478
1YK480 - YK487
1YK491 - YK493
1YK495 - YK499
1YK511 - YK516
1YK521 - YK530
1YK551 - YK571
1YK576 - YK577
1YK580 - YK585
1YK601 - YK602
1YK606 - YK607
1YK611 - YK616
1YK621 - YK634
1YK641 - YK644
1YK651 - YK665
1YK671 - YK672
1YK676 - YK677
1YK681 - YK686
1YK691
1YK695 - YK699
1YK701 - YK713
1YK716 - YK719
1YK721 - YK741
1YK751 - YK770
1YK776 - YK778
1YK781 - YK785
GroupVariable Number
1YK791 - YK792
1YK796 - YK797
1YK801 - YK899
1YK901 - YK912
1YK918 - YK919
1YK921 - YK929
1YK941 - YK999
1YL001 - YL005
1YL011 - YL016
1YL021 - YL024
1YL051 - YL052
1YL056 - YL057
1YL061
1YL066 - YL069
1YL076 - YL077
1YL101 - YL137
1YL201 - YL237
1YL241 - YL242
1YL271 - YL272
1YL281 - YL284
1YL301 - YL303
1YL311 - YL314
1YL316 - YL321
1YL351 - YL353
1YL371 - YL374
1YL401
1YL421 - YL429
1YL431 - YL444
1YL461 - YL478
1YL501 - YL509
1YL531 - YL534
1YL541 - YL551
1YL561 - YL579
GroupVariable Number
1YL591 - YL598
1YL601 - YL606
1YL611 - YL612
1YL616 - YL617
1YL621
1YL626
1YL631 - YL634
1YL636 - YL637
1YL661 - YL664
1YL676 - YL691
1YL696 - YL697
1YL701 - YL707
1YL731
1YL751 - YL752
1YL756 - YL757
1YL761 - YL780
1YL796 - YL797
1YL801 - YL815
1YL901 - YL910
1YL921 - YL940
1YL951 - YL968
1YM101 - YM103
1YM201 - YM244
1YM251 - YM299
1YM301 - YM399
1YM401 - YM415
1YM471
1YM481 - YM484
1YM501 - YM515
1YM521 - YM522
1YM541
1YM551 - YM553
1YM571 - YM572
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GroupVariable Number
1YM581 - YM582
1YM591 - YM599
1YM631 - YM634
1YM641 - YM652
1YM671 - YM674
1YM691 - YM699
1YM701 - YM710
1YM761 - YM765
1YM771 - YM779
1YN001 - YN016
1YN021 - YN024
1YN061
1YN071 - YN082
1YN091 - YN092
1YN101 - YN112
1YN121
1YN126
1YN201 - YN202
1YN211 - YN219
1YN231 - YN236
1YN261
1YN501
1YN531 - YN534
1YN551 - YN566
1YN581 - YN585
1YN591 - YN593
1YN601 - YN606
1YN651 - YN653
1YN661 - YN663
1YN666 - YN667
1YN671 - YN674
1YN701 - YN702
1YN741 - YN746
GroupVariable Number
1YN756 - YN758
1YQ001 - YQ003
1YQ011 - YQ021
1YQ026 - YQ029
1YQ036 - YQ045
1YQ201 - YQ207
1YQ231
1YQ241 - YQ251
1YQ281 - YQ284
1YQ291 - YQ296
1YQ301 - YQ302
1YQ321 - YQ324
1YQ331 - YQ334
1YQ346 - YQ347
1YQ351 - YQ367
1YQ371
1YQ401 - YQ403
1YQ451 - YQ454
1YQ456
1YQ461
1YQ471
1YQ501 - YQ520
1YQ601 - YQ606
1YQ610 - YQ614
1YR001 - YR098
1YR101 - YR105
1YR111 - YR124
1YR126 - YR144
1YR166 - YR182
1YR186 - YR198
1YR201 - YR215
1YR231 - YR294
1YR296 - YR297
GroupVariable Number
1YR301 - YR334
1YR338 - YR341
1YR361 - YR366
1YR371 - YR373
1YR376 - YR377
1YR381 - YR382
1YR386 - YR388
1YR391
1YR396 - YR399
1YR401 - YR405
1YR411 - YR413
1YR416 - YR418
1YR421 - YR424
1YR426 - YR455
1YR457 - YR499
1YR501 - YR506
1YR511 - YR520
1YR526 - YR544
1YR546 - YR551
1YR556 - YR562
1YR571 - YR582
1YR591 - YR592
1YR601 - YR605
1YR616 - YR658
1YR661 - YR663
1YR671 - YR673
1YR676 - YR678
1YR681 - YR682
1YR701 - YR769
1YR771 - YR799
1YR801 - YR827
1YR831 - YR838
1YR841 - YR899
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GroupVariable Number
1YR901 - YR903
1YR931 - YR934
1YR938 - YR944
1YR951 - YR998
1YS001 - YS002
1YS006 - YS009
1YS031 - YS032
1YS051 - YS073
1YS101 - YS120
1YS126 - YS142
1YS146 - YS160
1YS166 - YS194
1YS196 - YS197
1YS201 - YS209
1YS221 - YS225
1YS231 - YS236
1YS271 - YS288
1YS295 - YS296
1YS301 - YS348
1YS351 - YS378
1YS381 - YS386
1YS393 - YS395
1YS401
1YS451
1YS456 - YS457
1YS462 - YS465
1YS467
1YS501 - YS502
1YS506
1YS511 - YS518
1YS531
1YS536 - YS538
1YS541 - YS542
GroupVariable Number
1YS546
1YS551 - YS556
1YS561 - YS578
1YS581 - YS595
1YS601 - YS690
1YS701 - YS716
1YS721 - YS762
1YS771 - YS780
1YS806 - YS810
1YS816 - YS818
1YS823 - YS825
1YS851 - YS863
1YS876
1YS881 - YS884
1YS891 - YS894
1YS896 - YS897
1YS901 - YS909
1YS911 - YS957
1YS961 - YS974
1YS976 - YS977
1YS981 - YS987
1YS991 - YS998
1YT001 - YT004
1YT006
1YT026 - YT027
1YT031 - YT032
1YT036 - YT038
1YT061 - YT068
1YT101 - YT138
1YT176 - YT185
1YT191
1YT196 - YT199
1YT201
GroupVariable Number
1YT206 - YT207
1YT211 - YT213
1YT251 - YT299
1YT301 - YT307
1YT311 - YT312
1YT321 - YT324
1YT326 - YT355
1YT371 - YT372
1YT381
1YT391 - YT396
1YT401 - YT403
1YT411 - YT417
1YT427
1YT461 - YT477
1YT491 - YT492
1YT501 - YT521
1YT551 - YT552
1YT556 - YT563
1YT565
1YT571 - YT578
1YT601 - YT606
1YT701 - YT708
1YT723 - YT726
1YT761 - YT781
1YT791 - YT794
1YT796 - YT797
1YT801 - YT804
1YT811 - YT813
1YT826 - YT827
1YT831 - YT832
1YT841 - YT852
1YT856 - YT863
1YT885 - YT887
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GroupVariable Number
1YT891 - YT895
1YT901 - YT998
1YU001 - YU060
1YU201 - YU218
1YU301 - YU329
1YU901 - YU931
1YV001 - YV012
1YV021 - YV023
1YV030 - YV034
1YV037 - YV042
1YV045 - YV047
1YV051 - YV059
1YV081
1YV083 - YV084
1YV097 - YV099
1YV101 - YV154
1YV201 - YV203
1YV251 - YV252
1YV256 - YV257
1YV301 - YV312
1YV351 - YV368
1YV381 - YV388
1YV391 - YV394
1YV401
1YV411 - YV413
1YV431 - YV433
1YV441 - YV454
1YV461 - YV464
1YV467 - YV470
1YV501 - YV512
GroupVariable Number
1YV521
1YV571 - YV586
1YV596
1YV601 - YV605
1YV651 - YV674
1YV676
1YV695 - YV696
1YV701 - YV702
1YV711
1YV722 - YV731
1YV741 - YV794
1YV801 - YV820
1YV831 - YV848
1YV881 - YV883
1YV901 - YV915
1YV923 - YV926
1YV971 - YV983
1YW001
1YW011 - YW099
1YW101 - YW164
1YW201 - YW212
1YW226 - YW240
1YW245 - YW261
1YW263
1YW267 - YW281
1YW283 - YW285
1YW292 - YW299
1YW351
1YW356 - YW358
1YW361 - YW366
GroupVariable Number
1YW371 - YW399
1YW401 - YW430
1YW441 - YW445
1YW451 - YW452
1YW471 - YW472
1YW491 - YW498
1YW531 - YW536
1YW541 - YW545
1YW551 - YW580
1YW585 - YW591
1YW595 - YW596
1YW601
1YW610 - YW613
1YW616 - YW623
1YW666
1YW696 - YW699
1YW701 - YW715
1YW726 - YW731
1YW766 - YW775
1YW801 - YW803
1YW811 - YW813
1YW821
1YW831
1YW881
1YW891 - YW893
1YW906 - YW910
1YW916 - YW918
1YW921 - YW925
1YW971 - YW976
--
B. Spares Affected
None.
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2. CONCURRENT REQUIREMENTS
None.
3. COMPLIANCE
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to
Requirements Bulletin 737-55A1104 RB. The Airworthiness Directive will make the compliance tasks and
times given in Requirements Bulletin 737-55A1104 RB mandatory.
NOTE: Airplanes listed in the effectivity of this bulletin can be classified into one of the two configurations
specified in the group-configuration description table to determine initial inspection threshold in
accordance with this bulletin. Operators must determine airplane configuration based on the
definition given. Configuration is based on if the airplane has previously accomplished any of the
accepted freeplay measurement procedures of the horizontal stabilizer pivot hinges and the
jackscrew before the original issue date of Requirements Bulletin 737-55A1104 RB, AND freeplay
values are within Level 1 limits specified in APPENDIX H or corrective action was taken to bring
freeplay values to within the Level 1 limits.
The Boeing Company documents that follow are considered accepted freeplay measurement
procedures of the horizontal stabilizer pivot hinges and the jackscrew:
MOM-MOM-22-0187-01B dated April 6, 2022,
MOM-MOM-22-0187-01B(R1) dated May 27, 2022,
737-600/700/800/900 AMM TR 27-09-91/601 dated July-2022,
737-600/700/800/900 AMM Task 27-09-91-200-804 October-2022 revision,
737-600/700/800/900 AMM Task 27-09-91-200-804 June-2023 revision,
737-600/700/800/900 AMM Task 27-09-91-200-804 October-2023 revision.
Accomplish the required action(s), based on the applicable condition(s) in Tables 1-4, in accordance with
Accomplishment Instructions.
When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When
more than one ACTION is given for a CONDITION or an OPTION, do all of the ACTION numbers for that
CONDITION or OPTION.
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Group 1, Configuration 1:
Table 1: Initial Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Boeing Recommended Compliance Time
(Whichever Occurs Later)
ActionCondition
Within 6,200 flight
hours or within 12
months after the
original issue date of
the Requirements
Bulletin 737-
55A1104 RB,
whichever occurs
first.
Within 18,000 flight
hours or within 3
years, whichever oc-
curs first, after accom-
plishment of any of
the accepted freeplay
measurement proce-
dures identified in Re-
quirements Bulletin
737-55A1104 RB.
Whichever occurs first:
1. Before 42,500 total flight
hours.
2. Within 8 years after the
date of issuance of the
original standard certificate
of airworthiness or the
original export certificate of
airworthiness.
ACTION 1:
Do the freeplay mea-
surement procedure of
the horizontal stabilizer
pivot hinges and the
jackscrew.
All
Airplanes.
At the times specified in Table 3.ACTION 2:
Do the applicable on-
condition actions speci-
fied in Table 3.
Group 1, Configuration 2:
Table 2: Initial Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Boeing Recommended Compliance Time
(Whichever Occurs Later)
ActionCondition
Within 6,200 flight hours or
within 12 months after the orig-
inal issue date of the Require-
ments Bulletin 737-55A1104
RB, whichever occurs first.
Whichever occurs first:
1. Before 42,500 total flight hours.
2. Within 8 years after the date of is-
suance of the original standard certifi-
cate of airworthiness or the original ex-
port certificate of airworthiness.
ACTION 1:
Do the freeplay mea-
surement procedure of
the horizontal stabilizer
pivot hinges and the
jackscrew.
All
Airplanes.
At the times specified in Table 3.ACTION 2:
Do the applicable on-
condition actions speci-
fied in Table 3.
Table 3: Repetitive Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Repeat Interval
(Not to Exceed)
Boeing Recommended
Compliance Time
ActionCondition
18,000 flight hours or 3
years, whichever oc-
curs first.
-Repeat the freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
CONDITION 1: ALL
FREEPLAY VALUES D1,
D2, D3 AND H WITHIN
LEVEL 1 LIMITS. (a)
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Table 3: Repetitive Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Repeat Interval
(Not to Exceed)
Boeing Recommended
Compliance Time
ActionCondition
-At the times specified in Table 4.Do the applicable on-
condition actions speci-
fied in Table 4.
CONDITION 2: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 1 LIMITS, AND
NONE ARE OVER LEV-
EL 2 LIMITS. (a)
-Before further flight.CONDITION 3CONDITION 3: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 2 LIMITS. (a)
(ACTION 1):
Replace or repair any
worn parts.
-Before further flight, after replace-
ment or repair of any worn parts.
CONDITION 3
(ACTION 2):
Do the freeplay mea-
surement procedure
and make sure freeplay
values D1, D2, D3, and
H are within Level 1
limits. (a)
18,000 flight hours or 3
years, whichever oc-
curs first.
-CONDITION 3
(ACTION 3):
Repeat the freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
(a) Level 1 and Level 2 limits are specified in APPENDIX H.
Table 4: Requirements for Repair Deferral of Horizontal Stabilizer Pivot Hinges and the Jackscrew
Repeat Interval
(Not to Exceed)
Boeing Recommended
Compliance Time
ActionCondition
-Within 3,100 flight hours or within
6 months after last freeplay mea-
surement procedure was done in
accordance with Requirements
Bulletin 737-55A1104 RB,
whichever occurs first.
Do an interim freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
CONDITION 2: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 1 LIMITS, AND
NONE ARE OVER LEV-
EL 2 LIMITS. (a)
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Table 4: Requirements for Repair Deferral of Horizontal Stabilizer Pivot Hinges and the Jackscrew
Repeat Interval
(Not to Exceed)
Boeing Recommended
Compliance Time
ActionCondition
-Within 3,100 flight hours or within
6 months after last interim freeplay
measurement procedure accor-
dance with Requirements Bulletin
737-55A1104 RB, whichever oc-
curs first.
CONDITION 2.1 (AC-
TION 1):
Replace or repair any
worn parts.
CONDITION 2.1: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 1 LIMITS, AND
NONE ARE OVER LEV-
EL 2 LIMITS. (a)
-Before further flight, after replace-
ment or repair of any worn parts.
CONDITION 2.1 (AC-
TION 2):
Do the freeplay mea-
surement procedure
and make sure freeplay
values D1, D2, D3, and
H are within Level 1
limits. (a)
18,000 flight hours or 3
years, whichever oc-
curs first.
-CONDITION 2.1 (AC-
TION 3):
Repeat the freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
-At the times specified in Table 3.Do the applicable on-
condition actions speci-
fied in Table 3.
CONDITION 2.1.1:
FREEPLAY MEASURE-
MENT PROCEDURE
VALUES OBTAINED.
-Before further flight.CONDITION 2.2 (AC-
TION 1):
CONDITION 2.2: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 2 LIMITS. (a)
Replace or repair any
worn parts.
-Before further flight, after replace-
ment or repair of any worn parts.
CONDITION 2.2 (AC-
TION 2):
Do the freeplay mea-
surement procedure
and make sure freeplay
values D1, D2, D3, and
H are within Level 1
limits. (a)
18,000 flight hours or 3
years, whichever oc-
curs first.
-CONDITION 2.2 (AC-
TION 3):
Repeat the freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
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Table 4: Requirements for Repair Deferral of Horizontal Stabilizer Pivot Hinges and the Jackscrew
Repeat Interval
(Not to Exceed)
Boeing Recommended
Compliance Time
ActionCondition
-At the times specified in Table 3.Do the applicable on-
condition actions speci-
fied in Table 3.
CONDITION 2.2.1:
FREEPLAY MEASURE-
MENT PROCEDURE
VALUES OBTAINED.
(a) Level 1 and Level 2 limits are specified in APPENDIX H.
4. APPROVAL
This Requirements Bulletin was examined by the Federal Aviation Administration (FAA). The changes
specified in this document comply with the applicable regulations and are FAA approved, as well as European
Union Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved
airplanes listed in this Requirements Bulletin effectivity. This document and its approval were based on the
airplane in its original Boeing delivery configuration or as modified by other Boeing changes.
If an airplane has a non-Boeing modification or repair that affects a component or system also affected by
this Requirements Bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this Requirements Bulletin.
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5.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF
METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED
MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE
BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES
CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE.
CAUTION
NOTE: 1. This is an Enhanced Required for Compliance document. There will be a separate
Service Bulletin (SB) and a separate Requirements Bulletin (RB). If an RB is mandated
by an Airworthiness Directive (AD), then all applicable requirements specified in the
RB must be done. In the RB, the "Refer to the listed procedures..." column of the
table(s) in the Work Instructions is for reference only. The procedures in that column
are not required by the AD and are for guidance only. For the related SB, some
locations are marked RC Start and RC End to identify the requirements that are
restated from the RB. For the related SB, the areas between RC Start and RC End,
including sub-steps and any figures identified between RC Start and RC End, must
be done to comply with the AD. Therefore, an Alternative Method of Compliance
(AMOC) is required for any deviations to steps between RC Start and RC End,
including substeps and identified figures. For the related SB, the steps not between
RC Start and RC End may be deviated from using accepted methods in accordance
with the operator's maintenance or inspection program without obtaining approval
of an AMOC; this is provided that the steps between RC Start and RC End, including
sub-steps and identified figures, can still be done as specified, and the airplane can
be put back in an airworthy condition. Figures not required for compliance are omitted
from the RB.
2. This is an Enhanced Required for Compliance document. The Boeing processes
used to create the Service Bulletin (SB) and the Requirements Bulletin (RB) ensure
that the information between "RC Start" and "RC End" in the SB are identical to the
information in the same sections (Compliance, Work Instructions...) of the RB which
the SB refers to as the related document.
3. The compliance times for the actions in WORK INSTRUCTIONS are in Compliance.
4. Boeing Service Letter 737-SL-51-042, Damage Reporting and Repair Plan/Design
Guidelines, is an acceptable procedure to request information from Boeing for
additional structural repair instructions. The Service Letter describes what information
must be provided to Boeing before a structural repair can be provided.
5. Unless shown differently, these dimensions and tolerances are used:
– Linear dimensions are in inches
– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus
or minus 0.03 inch
– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch
– Angular tolerance is plus or minus 2 degrees
– Hole dimensions for standard solid rivets and fasteners are in Structural Repair
Manual (SRM) Chapter 51
– Torque Values:
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— Values for structural fasteners are given in 737 Structural Repair Manual,
Chapter 51.
— Values for airframe maintenance tasks are included in Chapter 20 of 737
Aircraft Maintenance Manual (AMM).
— Values for electrical maintenance tasks are included in Chapter 20 of
Standard Wiring Practices Manual (SWPM).
— Values for engine maintenance tasks are included in Chapter 70 of 737
Aircraft Maintenance Manual (AMM).
— Non-standard torque values for maintenance tasks are included in the
applicable installation step.
6. These work instructions refer to procedures included in other Boeing documents.
When the words "refer to" are used and the operator has an accepted alternative
procedure, the accepted alternative procedure can be used. When the words "in
accordance with" are included in the instruction, the procedure in the Boeing document
must be used.
7. Where the work instructions include installation of a kept part, a new or serviceable
part with the same part number can be installed as an alternative to the kept part.
8. If it is necessary to remove more parts for access, you can remove those parts. If
you can get access without removing identified parts, it is not necessary to remove
all of the identified parts. Jacking and shoring limitations must be observed.
9. Use the approved fastener, process and material substitutions in accordance with
SRM Chapter 51.
10. When more than one OPTION is given for a CONDITION, do only one of the OPTION
numbers. When more than one ACTION is given for a CONDITION or an OPTION,
do all of the ACTION numbers for that CONDITION or OPTION.
11. The instructions in Work Instructions and the figures can include operation of tools
or test equipment. Boeing Engineering Tool Drawings, the Illustrated Tool and
Equipment Manual, and the Special Tool and Ground Handling Drawing Index contain
data on versions of the tools or test equipment that you can use. It is permitted to
use replaced tools. It is not permitted to use superseded tools.
12. If the length of any fastener specified in this service bulletin does not meet installation
standards given in SRM Chapter 51, then a fastener of the same specification, or
an approved substitute, with a length which meets the installation standards given
in SRM Chapter 51 may be used. In addition, washers may be installed for fastener
grip length in accordance with SRM Chapter 51. Refer to SOPM 20-50-01 for alternate
full threaded fasteners (screws) needed for installation in this service bulletin.
13. Use of colors in Figures is based on guidance from the ATA e-Business Program
(ATA) iSpec 2200.
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### Page 21

14. Airplanes listed in the effectivity of this bulletin can be classified into one of the two
configurations specified in the group-configuration description table to determine
initial inspection threshold in accordance with this bulletin. Operators must determine
airplane configuration based on the definition given. Configuration is based on if the
airplane has previously accomplished any of the accepted freeplay measurement
procedures of the horizontal stabilizer pivot hinges and the jackscrew before the
original issue date of Requirements Bulletin 737-55A1104 RB, AND freeplay values
are within Level 1 limits specified in APPENDIX H or corrective action was taken to
bring freeplay values to within the Level 1 limits.
The Boeing Company documents that follow are considered accepted freeplay
measurement procedures of the horizontal stabilizer pivot hinges and the jackscrew:
MOM-MOM-22-0187-01B dated April 6, 2022,
MOM-MOM-22-0187-01B(R1) dated May 27, 2022,
737-600/700/800/900 AMM TR 27-09-91/601 dated July-2022,
737-600/700/800/900 AMM Task 27-09-91-200-804 October-2022 revision,
737-600/700/800/900 AMM Task 27-09-91-200-804 June-2023 revision,
737-600/700/800/900 AMM Task 27-09-91-200-804 October-2023 revision.
B. WORK INSTRUCTIONS
Actions Required For Compliance
1. Requirements
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 22

Group 1, Configuration 1:
Table 1: Initial Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed procedures
in SB 737-55A1104 Original
Issue or later approved revi-
sions as an accepted proce-
dure.
Method of ComplianceActionCondition
PART 1: OPEN ACCESS-ACTION 1:All Airplanes
PART 4: PREPARATIONDo the freeplay measure-
ment procedure of the hori-
zontal stabilizer pivot hinges
and the jackscrew.
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight ap-
plication example.
PART 2: CLOSE ACCESS-
--ACTION 2:
Do the applicable on-condi-
tion actions specified in Ta-
ble 3.
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 23

Group 1, Configuration 2:
Table 2: Initial Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed procedures
in SB 737-55A1104 Original
Issue or later approved revi-
sions as an accepted proce-
dure.
Method of ComplianceActionCondition
PART 1: OPEN ACCESS-ACTION 1:All Airplanes
PART 4: PREPARATIONDo the freeplay measure-
ment procedure of the hori-
zontal stabilizer pivot hinges
and the jackscrew.
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight ap-
plication example.
PART 2: CLOSE ACCESS-
--ACTION 2:
Do the applicable on-condi-
tion actions specified in Ta-
ble 3.
Table 3: Repetitive Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed proce-
dures in SB 737-55A1104
Original Issue or later ap-
proved revisions as an ac-
cepted procedure.
Method of ComplianceActionCondition
PART 1:-Repeat the freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
CONDITION 1: ALL
FREEPLAY VALUES D1,
D2, D3 AND H WITHIN
LEVEL 1 LIMITS. (a)
OPEN ACCESS
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4
and APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
PART 2:-
CLOSE ACCESS
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 24

Table 3: Repetitive Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed proce-
dures in SB 737-55A1104
Original Issue or later ap-
proved revisions as an ac-
cepted procedure.
Method of ComplianceActionCondition
--Do the applicable on-
condition actions speci-
fied in Table 4.
CONDITION 2: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 1 LIMITS, AND
NONE ARE OVER LEV-
EL 2 LIMITS. (a)
PART 3:-CONDITION 3CONDITION 3: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 2 LIMITS. (a)
PARTS REPLACEMENT(ACTION 1): Replace
or repair any worn
parts.
PART 1:-CONDITION 3
OPEN ACCESS(ACTION 2): Do the
freeplay measurement
procedure and make
sure freeplay values
D1, D2, D3, and H are
within Level 1 limits. (a)
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4
and APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
PART 2:-
CLOSE ACCESS
PART 1:-CONDITION 3
OPEN ACCESS(ACTION 3): Repeat
the freeplay measure-
ment procedure of the
horizontal stabilizer piv-
ot hinges and the
jackscrew.
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4
and APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
PART 2:-
CLOSE ACCESS
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 25

Table 3: Repetitive Inspection Requirements of the Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed proce-
dures in SB 737-55A1104
Original Issue or later ap-
proved revisions as an ac-
cepted procedure.
Method of ComplianceActionCondition
(a) Level 1 and Level 2 limits are specified in APPENDIX H.
Table 4: Requirements for Repair Deferral of Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed proce-
dures in SB 737-55A1104
Original Issue or later ap-
proved revisions as an ac-
cepted procedure.
Method of ComplianceActionCondition
PART 1:-Do an interim freeplay
measurement proce-
dure of the horizontal
stabilizer pivot hinges
and the jackscrew.
CONDITION 2: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 1 LIMITS, AND
NONE ARE OVER LEV-
EL 2 LIMITS. (a)
OPEN ACCESS
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
PART 2:-
CLOSE ACCESS
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 26

Table 4: Requirements for Repair Deferral of Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed proce-
dures in SB 737-55A1104
Original Issue or later ap-
proved revisions as an ac-
cepted procedure.
Method of ComplianceActionCondition
PART 3:-CONDITION 2.1CONDITION 2.1: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 1 LIMITS, AND
NONE ARE OVER LEV-
EL 2 LIMITS. (a)
PARTS REPLACEMENT(ACTION 1): Replace
or repair any worn
parts.
PART 1:
OPEN ACCESS
-CONDITION 2.1
(ACTION 2): Do the
freeplay measurement
procedure and make
sure freeplay values
D1, D2, D3, and H are
within Level 1 limits. (a)
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
PART 2:-
CLOSE ACCESS
PART 1:-CONDITION 2.1
OPEN ACCESS(ACTION 3): Repeat
the freeplay measure-
ment procedure of the
horizontal stabilizer piv-
ot hinges and the
jackscrew.
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
--Do the applicable on
condition actions speci-
fied in Table 3.
CONDITION 2.1.1:
FREEPLAY MEASURE-
MENT PROCEDURE
VALUES OBTAINED. PART 2:--
CLOSE ACCESS
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 27

Table 4: Requirements for Repair Deferral of Horizontal Stabilizer Pivot Hinges and the Jackscrew
Refer to the listed proce-
dures in SB 737-55A1104
Original Issue or later ap-
proved revisions as an ac-
cepted procedure.
Method of ComplianceActionCondition
PART 3:-CONDITION 2.2CONDITION 2.2: ANY
FREEPLAY VALUE D1,
D2, D3 OR H IS OVER
LEVEL 2 LIMITS. (a)
PARTS REPLACEMENT(ACTION 1): Replace
or repair any worn
parts.
PART 1:-CONDITION 2.2
OPEN ACCESS(ACTION 2): Do the
freeplay measurement
procedure and make
sure freeplay values
D1, D2, D3, and H are
within Level 1 limits. (a)
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
PART 2:-
CLOSE ACCESS
PART 1:-CONDITION 2.2
OPEN ACCESS(ACTION 3): Repeat
the freeplay measure-
ment procedure of the
horizontal stabilizer piv-
ot hinges and the
jackscrew.
PART 4:
PREPARATION
-FIGURE 1, FIGURE 2,
FIGURE 3, FIGURE 4 and
APPENDIX H
APPENDIX A: Weight Applica-
tion requirements and calcula-
tion of total reverse load.
-
APPENDIX C: Freeplay mea-
surement procedure weight
application example.
--Do the applicable on
condition actions speci-
fied in Table 3.
CONDITION 2.2.1:
FREEPLAY MEASURE-
MENT PROCEDURE
VALUES OBTAINED. PART 2:--
CLOSE ACCESS
(a) Level 1 and Level 2 limits are specified in APPENDIX H.
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 28 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
ELEVATOR
EFT STABILIZEI
PIVOT HINGE (D1
FRONT SPAR•  FRONT SPAR
CENTERLINE  CENTERLINE OF
OF LEFT  / STA 1154  RIGHT STABILIZER
STABILIZER  (STABILIZER
HINGE LINE)
FRONT SPAR OF  FRONT SPAR OF
RIGHT STABILIZER  LEFT STABILIZER
B
VIEW LOOKING AFT FROM FRONT SPAR OF LEFT AND RIGHT STABILIZERS  2997274
A-A
FIGURE 1: LEFT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 1 OF 4)
Original Issue: June 12, 2025
Export Controlled ECCN: 9E991  737-55A1104 RB
See page 1 for details  28 of 43

### Page 29 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
1.5 INCH
RADIUS MAX
RETAINER
EXISTING
FASTENER
LOCATION
BSTA
1156
REF
INBD
LEGEND:
I DIAL PLUNGER CONTACT AREA
LEFT SIDE IS SHOWN
(LEFT PIVOT HINGE INSPECTION IS SHOWN)
3009904
FIGURE 1: LEFT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 2 OF 4)
Original Issue: June 12, 2025
737-55A1104 RB
Export Controlled ECCN: 9E991
See page 1 for details  29 of 43

### Page 30 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
REAR SPAR  FRONT SPAR
OUTBOARD
LE STA
LE STA  LE STA 198.23  188.94  LESTA LE STA  207.53  226.13
179.64  LE STA  LE STA
216.83  244.72
LE STA  235.43  LE STA  263.30
/LE STA /  LE STA
254.02  281.91
LE STA  LE STA
272.62  300.51
LE STA  LE STA
291.21  319.23
LE STA
309.00 LE STA
327.33
ELEV STA
94.07  12.00
ELEV STA  INCHES
121.59  MAX /
EDGE  TRAILING  ELEV STA  149.12  ELEV STA  176.64
BEAM  ELEV STA
195.00  ELEV STA
TRAILING  231.70
EDGE  ELEV STA  213.32  ELEV STA  250.04  STAB BL  254.66  STAB BL
ELEV STA  281.81
265.45
D
INBD
RIGHT STABILIZER IS SHOWN
(LEFT PIVOT HINGE INSPECTION IS SHOWN)
LEGEND:  B-B
WEIGHT APPLICATION AREA  3009905
FIGURE 1: LEFT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 3 OF 4)
Original Issue: June 12, 2025
Export Controlled ECCN: 9E991  737-55A1104 RB
See page 1 for details  30 of 43

### Page 31

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)(i)1STD-1238DIAL INDICATORAttach1
(a)(b)(i)1STD-1279MOUNTAttach
MOVEMENT OF EQUIPMENT OR PERSONNEL INSIDE THE FUSELAGE CAN CAUSE
FLUCTUATIONS IN THE DIAL INDICATOR READING. MAKE SURE THE READING IS
STABLE AT ZERO BEFORE PROCEEDING.CAUTION
(c)1STD-1238DIAL INDICATORAdjust2
(d)(e)--WEIGHTSApply3
MOVEMENT OF EQUIPMENT OR PERSONNEL INSIDE THE FUSELAGE CAN CAUSE
FLUCTUATIONS IN THE DIAL INDICATOR READING. MAKE SURE THE READING IS
STABLE, THEN MEASURE THE FREEPLAY VALUE.CAUTION
(f)--DIAL INDICATOR
VALUE
Record4
(g)(h)--WEIGHTSRemove5
-1STD-1238DIAL INDICATORRemove6
-1STD-1279MOUNTRemove
(a) Attach dial indicator with a mount or equivalent to the left side of the fuselage at the Station (STA) 1156
Pivot Bulkhead. Refer to 737-600/700/800/900 AMM 27-09-91 as an accepted procedure.
(b) Make sure the dial indicator plunger does not slip on the contact area surface during the freeplay mea-
surement procedure. Make sure the plunger is not in contact with any fastener head. Position indicator
to allow for subsequent plunger extension and dial travel of 0.13 inch minimum.
(c) Set dial indicator to zero.
(d) Calculate the total reverse load according to weights and locations selected. A total reverse load of 2500
+/- 200 lbs. is required. Make sure the weights do not cause damage.
(e) Place weights as required on top of the right side stabilizer front spar in the area shown.
(f) Record the value from the dial indicator reading as "D1". This value should represent the magnitude of
the extension of the plunger of the dial indicator.
(g) Remove the weights from the right side stabilizer.
(h) After removal of all weights, make sure the dial indicator value returns to 0 +/- 0.003 inch. If this is not
met, the freeplay value obtained is not valid. To troubleshoot, check the plunger contact, the mount, and
the function of the dial indicator, and then redo all the steps in the step table.
(i) Refer to 737-600/700/800/900 AMM, Front Matter, Paragraph 18 for Tool Lists and Paragraph 19 for
Supplier List. Any approved equivalent parts are acceptable.
FIGURE 1: LEFT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 4 OF 4)
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Original Issue: June 12, 2025
737-55A1104 RB
31 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 32 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
ELEVATOR
RIGHT STABILIZER
PIVOT HINGE (D2)
FRONT SPAR
CENTERLINE  •FRONT SPAR
OF LEFT  CENTERLINE
STABILIZER  STA 1154  OF RIGHT
(STABILIZER  HINGE LINE)  STABILIZER
4X6
FRONT SPAR OF  FRONT SPAR OF
RIGHT STABILIZER  LEFT STABILIZER
B
VIEW LOOKING AFT FROM FRONT SPAR OF LEFT AND RIGHT STABILIZERS  2997197
A-A
FIGURE 2: RIGHT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 1 OF 4)
Original Issue: June 12, 2025
737-55A1104 RB
Export Controlled ECCN: 9E991
See page 1 for details  32 of 43

### Page 33 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
1.5 INCH
RADIUS MAX
RETAINER
EXISTING
FASTENER
LOCATION
BSTA
1156
REF
INBD
LEGEND:
DIAL PLUNGER CONTACT AREA
RIGHT SIDE IS SHOWN
(RIGHT PIVOT HINGE INSPECTION IS SHOWN)
3009915
FIGURE 2: RIGHT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 2 OF 4)
Original Issue: June 12, 2025
Export Controlled ECCN: 9E991  737-55A1104 RB
See page 1 for details  33 of 43

### Page 34 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
OUTBOARD  FRONT SPAR  REAR SPAR
LE STA
198.23  LE STA
LE STA  188.94
LE STA  226.13  207.53  LE STA
LE STA  LE STA  179.64
244.72  216.83
LE STA  LE STA
263.30  235.43
LE STA  \ LE STA
281.91  254.02
LE STA  LE STA
300.51  272.62
LE STA  LE STA
319.23  291.21
LE STA
LE STA  309.00
327.33
З
12.00  ELEV STA
INCHES  94.07
MAX  ELEV STA
121.59
ELEV STA  176.64  ELEV STA  149.12  TRAILING  EDGE
ELEV STA  BEAM
ELEV STA  231.70  195.00  TRAILING
STAB BL  ELEV STA  ELEV STA  EDGE
STAB BL  254.66  250.04  213.32
281.81  ELEV STA
265.45
F
D
INBD
LEFT STABILIZER IS SHOWN
(RIGHT PIVOT HINGE INSPECTION IS SHOWN)
LEGEND:  B-B
L WEIGHT APPLICATION AREA  3009913
FIGURE 2: RIGHT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 3 OF 4)
Original Issue: June 12, 2025
737-55A1104 RB
Export Controlled ECCN: 9E991
See page 1 for details  34 of 43

### Page 35

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)(i)1STD-1238DIAL INDICATORAttach1
(a)(b)(i)1STD-1279MOUNTAttach
MOVEMENT OF EQUIPMENT OR PERSONNEL INSIDE THE FUSELAGE CAN CAUSE
FLUCTUATIONS IN THE DIAL INDICATOR READING. MAKE SURE THE READING IS
STABLE AT ZERO BEFORE PROCEEDING.CAUTION
(c)1STD-1238DIAL INDICATORAdjust2
(d)(e)--WEIGHTSApply3
MOVEMENT OF EQUIPMENT OR PERSONNEL INSIDE THE FUSELAGE CAN CAUSE
FLUCTUATIONS IN THE DIAL INDICATOR READING. MAKE SURE THE READING IS
STABLE, THEN MEASURE THE FREEPLAY VALUE.CAUTION
(f)--DIAL INDICATOR
VALUE
Record4
(g)(h)--WEIGHTSRemove5
-1STD-1238DIAL INDICATORRemove6
-1STD-1279MOUNTRemove
(a) Attach dial indicator with a mount or equivalent to the right side of the fuselage at the Station (STA) 1156
Pivot Bulkhead. Refer to 737-600/700/800/900 AMM 27-09-91 as an accepted procedure.
(b) Make sure the dial indicator plunger does not slip on the contact area surface during the freeplay mea-
surement procedure. Make sure the plunger is not in contact with any fastener head. Position indicator
to allow for subsequent plunger extension and dial travel of 0.13 inch minimum.
(c) Set dial indicator to zero.
(d) Calculate the total reverse load according to weights and locations selected. A total reverse load of 2500
+/- 200 lbs. is required. Make sure the weights do not cause damage.
(e) Place weights as required on top of the left side stabilizer front spar in the area shown.
(f) Record the value from the dial indicator reading as "D2".This value should represent the magnitude of
the extension of the plunger of the dial indicator.
(g) Remove the weights from the left side stabilizer.
(h) After removal of all weights, make sure the dial indicator value returns to 0 +/- 0.003 inch. If this is not
met, the freeplay value obtained is not valid. To troubleshoot, check the plunger contact, the mount, and
the function of the dial indicator, and then redo all the steps in the step table.
(i) Refer to 737-600/700/800/900 AMM, Front Matter, Paragraph 18 for Tool Lists and Paragraph 19 for
Supplier List. Any approved equivalent parts are acceptable.
FIGURE 2: RIGHT HORIZONTAL STABILIZER PIVOT HINGE - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 4 OF 4)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: June 12, 2025
737-55A1104 RB
35 of 43
REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 36 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
ELEVATOR
FRONT SPAR  FRONT SPAR
CENTERLINE  CENTERLINE OF
OF LEFT  STA 1154  RIGHT STABILIZER
STABILIZER  STABILIZER _
HINGE LINE)
FRONT SPAR OF  FRONT SPAR OF
RIGHT STABILIZER  LEFT STABILIZER
VIEW LOOKING AFT FROM FRONT SPAR OF LEFT AND RIGHT STABILIZERS  3006725
A-A
FIGURE 3: HORIZONTAL STABILIZER JACKSCREW - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 1 OF 5)
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737-55A1104 RB
Export Controlled ECCN: 9E991
See page 1 for details  36 of 43

### Page 37 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
JACKSCREW 4
FITTING
STABILIZER
TRIM
JACKSCREW
V
BODY STATION
DIAL INDICATOR  CONTACT AREA  1088 (BULKHEAL  STRUCTURE)
STABILIZER
CENTER
SECTION
• FITTING
₴ 40
JACKSCREW
FITTING
3006729
FIGURE 3: HORIZONTAL STABILIZER JACKSCREW - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 2 OF 5)
Original Issue: June 12, 2025
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Export Controlled ECCN: 9E991
See page 1 for details  37 of 43

### Page 38 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
FUSELAGE
WEIGHT
APPLICATION
AREA
3 5
STAB
STA
83.50  - FORWARD AND
INBOARD CORNER
OF INSPAR SKIN
FRONT SPAR
BEND POINT•
12 INCHES  25.6 INCHES
FORWARD EDGE OF
UPPER INSPAR SKIN  STABILIZER
UPPER INSPAR
SKIN
D
INBD
LEFT STABILIZER IS SHOWN,
(RIGHT STABILIZER IS OPPOSITE)
3009950
FIGURE 3: HORIZONTAL STABILIZER JACKSCREW - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 3 OF 5)
Original Issue: June 12, 2025
Export Controlled ECCN: 9E991  737-55A1104 RB
See page 1 for details  38 of 43

### Page 39

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)(i)1STD-1238DIAL INDICATORAttach1
(a)(b)(i)1STD-1279MOUNTAttach
MOVEMENT OF EQUIPMENT OR PERSONNEL INSIDE THE FUSELAGE CAN CAUSE
FLUCTUATIONS IN THE DIAL INDICATOR READING. MAKE SURE THE READING IS
STABLE AT ZERO BEFORE PROCEEDING.CAUTION
(c)1STD-1238DIAL INDICATORAdjust2
(d)(e)--WEIGHTSApply3
MOVEMENT OF EQUIPMENT OR PERSONNEL INSIDE THE FUSELAGE CAN CAUSE
FLUCTUATIONS IN THE DIAL INDICATOR READING. MAKE SURE THE READING IS
STABLE, THEN MEASURE THE FREEPLAY VALUE.CAUTION
(f)--DIAL INDICATOR
VALUE
Record4
(g)(h)--WEIGHTSRemove5
-1STD-1238DIAL INDICATORRemove6
-1STD-1279MOUNTRemove
(a) Attach dial indicator with a mount or equivalent to the Station (STA) 1088 bulkhead structure. Refer to
737-600/700/800/900 AMM 27-09-91 as an accepted procedure.
(b) Make sure the dial indicator plunger does not slip on the contact area surface during the freeplay mea-
surement procedure. Make sure the plunger contact point is at least 0.05 inch away from the peripheral
fillet radius of the designated contact area. Position indicator to allow for subsequent plunger contraction
and dial travel of 0.13 inch minimum.
(c) Set dial indicator to zero.
(d) Place weights as required on top of the left and right stabilizer front spars in the areas shown. Application
area perimeter to be within +/- 2 inches of the perimeter shown. Weights to be applied within the application
area. A total of 1000lbs +/- 40lbs is required, equally placed with 500lbs +/- 20lbs on each side.
(e) Distribute the weights evenly within the region shown to avoid localized high pressure at contact. Protect
the upper surface of the horizontal stabilizer as required to make sure that the weights do not cause
damage.
(f) Record the value from the dial indicator reading as "D3". This value should represent the magnitude of
the contraction of the plunger of the dial indicator.
(g) Remove the weights from the left and right side stabilizers.
(h) After removal of all weights, make sure the dial indicator value returns to 0 +/- 0.003 inch. If this is not
met, the freeplay value obtained is not valid. To troubleshoot, check the plunger contact, the mount, and
the function of the dial indicator, and then redo all the steps in the step table.
FIGURE 3: HORIZONTAL STABILIZER JACKSCREW - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 4 OF 5)
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### Page 40

More DataQtyIdentificationNameTaskStep
(i) Refer to 737-600/700/800/900 AMM, Front Matter, Paragraph 18 for Tool Lists and Paragraph 19 for
Supplier List. Any approved equivalent parts are acceptable.
FIGURE 3: HORIZONTAL STABILIZER JACKSCREW - FREEPLAY MEASUREMENT PROCEDURE
(SHEET 5 OF 5)
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 41 (OCR)

REQUIREMENTS BULLETIN 737-55A1104
ALERT  ALERT
ELEVATOR
LEFT STABILIZER PIVOT
HINGE FREEPLAY VALUE (D1)
FRONT SPAR  CENTERLINE  OF LEFT  RIGHT STABILIZER PIVOT  HINGE FREEPLAY VALUE (D2)
STABILIZER
FRONT SPAR
- TAIL CONE  CENTERLINE
STA 1154  OF RIGHT
(STABILIZER ~  STABILIZER
HINGE LINE)
STABILIZER JACKSCREW
FREEPLAY VALUE (D3)
3006830
FIGURE 4: HORIZONTAL STABILIZER PIVOT HINGES AND THE JACKSCREW - TOTAL FREEPLAY
MEASUREMENT PROCEDURE VALUE
(SHEET 1 OF 2)
Original Issue: June 12, 2025
Export Controlled ECCN: 9E991  737-55A1104 RB
See page 1 for details  41 of 43

### Page 42

More DataQtyIdentificationNameTaskStep
(a)--TOTAL HORIZONTAL
STABILIZER
FREEPLAY VALUE
Record1
(a) Use the values D1, D2, and D3, to calculate and record the total freeplay of the horizontal stabilizer, "H".
H= 1.25 X D3 + [(D1+D2)/2].
FIGURE 4: HORIZONTAL STABILIZER PIVOT HINGES AND THE JACKSCREW - TOTAL FREEPLAY
MEASUREMENT PROCEDURE VALUE
(SHEET 2 OF 2)
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REQUIREMENTS BULLETIN 737-55A1104
ALERTALERT

### Page 43

This page defines the limits to adhere to when carrying out the freeplay measurement procedures at the following
support locations of the horizontal stabilizer: the left side pivot hinge ("D1"), the right side pivot hinge ("D2"), the
jackscrew ("D3"), and the combined value ("H"). Use the freeplay value limits together with the freeplay values
measured to determine applicable on-condition corrective action.
Level 2 LimitLevel 1 LimitValue ID
0.0800.066D1 (left pivot)
0.0800.066D2 (right pivot)
0.0560.056D3 (jackscrew)
0.0950.078H (combined)
APPENDIX H:  FREEPLAY VALUE LIMITS
(SHEET 1 OF 1)
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REQUIREMENTS BULLETIN 737-55A1104
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