[32起落架] 空中模式设置的三种方式及注意事项

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Service Request ID:  4-4946405681

SUBJECT: Questions about Put the Airplane in the Air Mode with Deactuators

DESCRIPTION:

When China Southern perform REF/A/ and they choose put the airplane in the air mode with deactuators, they found the REF/B/ deactuator cannot set the airplane into air mode, they checked it several times and check the status in PSEU and confirmed the REF/B/ can not set it.

In REF/A/ STEP H (2) there is a note "NOTE: As an option, deactuators can be constructed as follows: Material: 5052, 6061, 7075,or 2024 aluminum or sheet copper. For rectangular sensors - 1.5 in. (38 mm) x 0. 75 in.(19 mm) x0.05 in. (1.27 mm). For round sensors-1.0 in. (25 mm) x 1.0 in. (25 mm) x0.05 in. (1.27 mm) ". So the thickness should be 0.05 in, but as in the REF/C/ drawing the thickness of the REF/B/ is 0.025in.

So China Southern tried with two REF/B/ to get enough thickness to set the airplane into air mode and it do worked. 

RESPONSE AND/OR REQUIRED ACTION:

1.China Southern want to ask how many deactuators should be used to put the airplane in the air mode with deactuators, China Southern think it should be 6, two for nose landing gear and four for main landing gear, but in tooling set A27092-106, there is only one REF/B/, China Southern suggest make it clear in Tool/Equipment descriptions like "6 sets of A27092-106 needed" or add more REF/B/ in tooling set A27092-106, or operators may need to solve this problem when they perform the task.

2.Please check if the thickness is enough for REF/B/ to set the airplane in air mode, as to China Southern's experience the thickness need to be doubled to set the airplane to air mode.

3.Please advise if the AMM will be revised.

RESPONSE:

Boeing has reviewed China Southern Airlines' inquiry and offers the following response:

Q1: China Southern Airlines want to ask how many deactuators should be used to put the airplane in the air mode with deactuators, China Southern think it should be 6, two for nose landing gear and four for main landing gear, but in tooling set A27092-106, there is only one REF/B/, China Southern suggest make it clear in Tool/Equipment descriptions like "6 sets of A27092-106 needed" or add more REF/B/ in tooling set A27092-106, or operators may need to solve this problem when they perform the task.

A1: Boeing concurs with China Southern Airlines' assessment for using six sets of A27092-106 or adding more -62 deactuators into the A27092-106 tool set to perform the Ref /A/ AMM TASK 32-09-00-860-801.

Q2: Please check if the thickness is enough for REF/B/ to set the airplane in air mode, as to China Southern's experience the thickness need to be doubled to set the airplane to air mode.

A2: Boeing has No Technical Objection (NTO) to the use of two -62 deactuators (0.025 in. thickness) to create a deactuator that has a total thickness of 0.05 in. to set the airplane to Air Mode, per the NOTE in Step H(2) of Ref /A/ AMM task.

Boeing confirms that, in some cases, the required thickness for the deactuator needs to be 0.05 in. to put the airplane in Air Mode. Boeing recently replaced the A27092-106 tool set with A27092-139 (Drawing A27092, Sheet 1, Revision "T") for future procurement to improve tool functions. The -139 contains the new -140 deactuator assembly with a -142 deactuator plate of 0.050 in. thickness. The -142 deactuator plate (0.05 in. thickness) replaces the -65 deactuator plate (0.025 in. thickness).

Boeing recommends that the A27092-106 be replaced with A27092-139, per the latest A27092 drawing, if the A27092-62 deactuator fails to put the airplane in Air Mode. 

Q3: Please advise if the AMM will be revised.

A3: Boeing has reviewed the Ref /A/ AMM TASK 32-09-00-860-801 and confirms that the TASK is correct as is. There is no plan to revise the Ref /A/ AMM task at this time.

The term No Technical Objection (NTO) is used by The Boeing Company in circumstances where Boeing has undertaken a limited review of a proposed technical or airplane operating procedure change as initiated by an operator. This review is solely based on the supporting data provided by the requesting operator and is intended to determine any obvious technical, operating procedure, or other flight crew interface issue. This NTO is not a formal approval or certification, nor is it an assurance that the operator proposal will function as intended by the operator. Any coordination with regulatory authorities regarding the use of this NTO is the sole responsibility of the operator. This Boeing No Technical Objection (NTO) is based upon the airplane being in the original delivered configuration as modified by applicable Boeing service bulletins (not specific operator STCs or non-Boeing airplane modifications) and the procedures or checklists furnished by the operator for review in conjunction with this request. The operator should periodically review any changes to its procedures as well as future Boeing revisions to operating procedures and checklists to ensure the contents of this NTO remain valid. If there are any questions, the operator should contact The Boeing Company immediately.