新BSCU软件L4.11介绍

New BSCU Software L4.11 introduced

-参考资料Airbus IPC RIL ISI

-Reference: Airbus IPC RIL ISI

1.背景

Background

新BSCU软件标准L4.11已于2024年9月通过空客MOD 170252在生产中以及通过空客SB 32-1522/32-1523进行改装时推出。

New Braking & Steering Control Unit (BSCU) software standard L4.11 has been introduced in September 2024 through Airbus MOD 170252 in production and in retrofit through Airbus SB 32-1522/32-1523.

L4.9B 标准，P/N E21327X06

L4.9B Standard is P/N E21327X06

L4.10标准,P/N E21327X07

L4.10 Standard is P/N E21327X07

L4.11标准,P/N E21327X08

L4.11 Standard will be P/N E21327X08

有关BSCU PN演化的更多信息，请参见ISI 32.42.00062和ISI 32.42.00190。

More information related to BSCU PN evolution can be found in ISI 32.42.00062 and ISI 32.42.00190.

2.描述

Description

针对A321XLR飞机所引入的变更，已开发出新的BSCU软件标准L4.11。这些变更包括具有不同性能特性的新型刹车系统，需要对BSCU软件进行更新，以实现特定的防滞调校和压力上升率控制。此外，BSCU还为A321XLR飞机/刹车系统新增了专用的销钉编程设置。

The new BSCU software standard L4.11 has been developed for the changes introduced by the A321XLR aircraft. These changes such as new brakes with different performance characteristics require an update to the BSCU software; with specific antiskid tuning and pressure rise rate control. In addition, the BSCU has a new specific pin-programming setting allocated to A321XLR aircraft/brakes.

这款新的软件修改版本L4.11同样适用于A320FAM机队，并对刹车与前轮转弯控制系统（BSCS）引入了多项改进，主要变化如下:

This new software modification L4.11 is also applicable to the A320FAM fleet and introduces a number of additional improvements to the Braking and Steering Control System (BSCS), with the main changes detailed below:

正常伺服活门（NSV）漂移监控

Normal Servo-Valve (NSV) drift monitoring

在调查两起运行事件时发现，由于多种因素的综合作用，导致了具备增强可维护性与制造（EMM）BSCS的飞机上正常和备用刹车系统失效。经评估，NSV漂移是引发意外警告并随后导致刹车系统失效的主要原因。因此，在EMM前飞机上引入了检验SB 32-1483——“检查正常刹车伺服活门漂移”（详情请参见ISI 32.42.00165）。

During the investigation of two in-service events where a combination of different factors led to loss of normal and alternate braking systems on aircraft with pre-Enhanced Maintainability and Manufacturing (EMM) BSCS. The NSV drift was assessed to be a major contributing factor for the unexpected warning triggering and subsequent loss of braking system. As a result, an inspection SB 32-1483 - CHECK OF NORMAL BRAKE SERVOVALVE DRIFT was introduced on pre-EMM aircraft (please refer to ISI 32.42.00165 for further information).

BSCU软件L4.11修改了现有的单个NSV漂移第3类监控阈值（故障代码73-80 - BRK NORM SERVOVLVX(xxGG)），并引入了一种新的第1类监控，用于检测同一档位上两个NSV的漂移情况。因此，如果安装了BSCU软件标准L4.11，则无需再执行SB 32-1483检查。

The BSCU software L4.11 modifies the threshold of the existing single NSV drift class-3 monitoring (Fault codes 73-80 - BRK NORM SERVOVLVX(xxGG)) and introduces a new class-1 monitoring to detect if two NSV drift on the same gear. Therefore if the BSCU software standard L4.11 is installed it cancels the need for inspection SB 32-1483.

自动刹车解除阈值的修改

Modification of Autobrake disengagement threshold

调整自动刹车解除阈值的目的是降低因刹车踏板偏移导致的意外解除风险，并实现空客机队中自动刹车踏板解除阈值的一致性。以下阈值将根据AMM 32-42-00-00-*实施：

The modification of Autobrake disengagement threshold is to reduce the risk of inadvertent disengagement due to brake pedal deflections and provides harmonization across the Airbus fleet for Autobrake Pedal disengagement thresholds. The following thresholds will be implemented as per AMM 32-42-00-00 (*):

Table 1: Autobrake pedal disconnection - target thresholds for A320FAM

(*) 注意：AMM 32-42-00-00 目前正在修订中，以提供上述列出的所有相关阈值。

(*) NOTE: AMM 32-42-00-00 is currently under revision to provide all relevant thresholds as listed above.

冲出跑道预防系统（ROPS）step-3功能集成

Integration of Runway Overrun Prevention System (ROPS) step-3 function

ROPS Step 3 在 ROPSOPS 功能中引入了 RCDF（飞机级别跑道状况降级功能）。停止距离（ROP 距离）的计算方式已修改，以在每个机轮上包含一个低防滞激活布尔值，用于为 RCDF 提供输入（仅适用于 EMM BSCS）。

The ROPS Step 3 introduces RCDF (an aircraft level Runway Condition Downgrading Function) to the ROPS function. The computation of stopping distance (ROP distance) is modified to include a low anti-skid activity Boolean per wheel in order to feed the RCDF (for EMM BSCS only).

改进A321 MABS刹车的压力上升率控制。

Improvement of the Pressure Raise Rate control for A321 MABS Brakes.

在A321 MABS刹车飞行测试之后，引入了着陆时压力上升率控制的修改。

Following the A321 MABS brakes flight test, a modification of the pressure rise rate control at landing was introduced.

刹车解除监控

Retraction braking monitoring

现有的三级故障信息（故障代码901-L/G NORM CTL LEVER (6GA)/BSCU(10GG)）用于检测起落架控制手柄导致的预防刹车解除失效，现升级为一级故障信息，以确保飞行机组能够及时发现并报告该故障。

The existing class 3 failure message (Fault Code 901 - L/G NORM CTL LEVER (6GA)/BSCU(10GG)) that detects the failure of the landing gear control lever preventing retraction braking is upgraded to a class 1 failure message, to ensure that the detected failure is indicated to the flight crew.

L4.11 软件引入的所有更改列表详见 VSB E21327-32-3511。

The complete list of changes introduced by the L4.11 software is listed in the VSB E21327-32-3511.

3.可互换性

Interchangeability

BSCU软件L4.11（PNE21327X08）和BSCU软件L4.10（PN E21327X07）在所有A320FAM配置下均可完全互换，但有两个特定情况除外：

BSCU software L4.11 (PN E21327X08) and BSCU software L4.10 (PN E21327X07) are fully interchangeable on all A320FAM configurations, except for two specific cases:

-BSCU软件L4.11未在配备MABS刹车（P/N50115XX-X）的A321CEO飞机上通过认证。

-BSCU software L4.11 is not certified on A321CEO aircraft equipped with MABS Brakes (P/N 50115XX-X) ,

-BSCU软件L4.10未在A321XLR（A321-2XXNY）飞机上通过认证。

-BSCU software L4.10 is not certified on A321XLR (A321-2XXNY) aircraft.

上述BSCU标准之间的条件性互换性导致了空客工具在支持IPC建造过程中出现互换性中断。这种互换性的中断限制了可在IPC工具中展示的备件种类。因此，为了显示所有可安装在A320系列飞机上的潜在BSCU件号，空客已在IPC中引入了一项DTN（设计技术说明）。

The above conditional interchangeability between BSCU standards led to a break in the interchangeability chain in Airbus Tools supporting the IPC construction. This break in interchangeability limits the available spare parts that can be displayed in the IPC tool. Therefore, in order to show all potential BSCU part numbers that can be installed on A320Fam aircraft, Airbus has introduced a DTN (Design Technical Note) into the IPC.

DTN参考编号D00715337包含每种飞机型号的矩阵，其中ICY代码位于当前安装的BSCU件号与备件BSCU件号之间。

The DTN Reference D00715337 contain matrixes for each aircraft model with the ICY code between the current installed BSCU Part Number and the spare BSCU Part Number.

DTN D007153377 目前可通过空客全球机械图纸工具获取。引用 DTN D00715337 的 IPC 修订版将于 20255 年 11 月发布。如运营商需要安装当前其 IPC 中未显示但根据 DTNNN 矩阵技术上适用于该飞机的 BSCU件号，可应要求提前获取 IPC 的副本。

The DTN D00715337 is currently available through the Airbus World Mechanical Drawings tool. The IPC revision referencing DTN D00715337 will be available in November 2025. An advance copy of the IPC can be made available upon request, for example if an operator needs to install a BSCU part number currently not shown in their IPC but technically applicable to the aircraft as per the DTN matrix.

4.附加说明：

Additional Notes:

标准L4.11的实施将适用特定的商业政策。BSCU软件标准L4.11的改装所需材料，自SB 32-1522/1523文件发出之日起，将在5年内免费提供（FOC）。有关改装的具体条件，请参阅RIL SA32M24000205。

A specific commercial policy will apply to the embodiment of Standard L4.11. The material required for retrofitting the BSCU Software Standard L4.11 will be provided on a Free-Of-Charge (FOC) basis over a duration of 5 years from the date of dispatch of SB 32-1522/1523. Please refer to RIL SA32M24000205 for detailed retrofit conditions.

服务公告（SB）32-1522（CEO）和32-1523（NEO）于2025年10月发布，旨在为A320FAM机型引入BSCU新软件标准L4.11的在役改装。

Service Bulletins (SB) 32-1522 (CEO) and 32-1523 (NEO) were published in October 2025 to introduce in-service retrofit for BSCU new Software Standard L4.11 on A320FAM.

5.改装BSCU软件以符合标准L4.11

Modify BSCU software to standard L4.11

文件参考

DOCUMENT REFERENCES

内容

CONTEXT

(1)原因

Reason

A321超远程（XLR）飞机对刹车系统进行了多项改进，因此需要更新BSCU的软件。

The A321 Extra Long Range (XLR) aircraft introduced several changes to the braking system which required an update to the Braking and Steering Control Unit (BSCU) software.

此外，该软件的更新还引入了安全性和操作方面的改进，在运营中解决以下问题：

In addition, the updates to this software introduce safety and operational enhancements, which enables us to address the following in service events:

-由于刹车失效导致的低速滑行异常，其中正常伺服活门（NSV）漂移是促成因素之一，仅适用于增强可维护性与制造（EMM）前的飞机。

-Low speed taxiway excursion due to loss of braking where Normal Servo Valve (NSV) Drift was a contributing factor, applicable to pre- Enhanced Maintainability and Manufacturing (EMM) aircraft only.

-因着陆时无意踩下刹车踏板导致的自动刹车系统断开。

-Autobrake disconnection caused by inadvertent brake pedal deflectionat touchdown.

(2)解决方案

Solution

空客SB系列A320-32-1522和A320-32-1523版本发布，旨在说明BSCU软件标准L4.11的引入。该软件开发用于适配A321 XLR系统的变化，并对A320系列飞机的刹车与转向控制系统（BSCS）进行多项改进，例如：

Airbus SBs A320-32-1522 and A320-32-1523 are issued to describe the introduction of BSCU software standard L4.11. The software was developed to accommodate the A321 XLR changes and integrate several improvements to the Braking and Steering Control System (BSCS) for the A320 family fleet, such as:

-增强型NSV漂移监控

-Robustified NSV drift monitoring

-自动制动解除阈值提高

-Increase of the autobrake disengagement threshold

-A321 MABS刹车压力提升率控制的改进

-Improvement of the pressure raise rate control for A321 MABS brakes

-将起落架手柄失效信息重新分类，以确保飞行机组得到正确通知

-Reclassification of landing gear control lever failure message to ensure proper flight crew notification

改进后的软件可通过重新编程机载可更换模块（OBRMs）来实现。重编程可在供应商的车间（Safran Landing Systems）进行，或在运营商内部车间完成，前提是该车间已配备相应设备。

The improved software can be incorporated by reprogramming the On Board Replaceable Modules (OBRMs). The reprogramming will be done in the supplier’s shop (Safran Landing Systems) or in-house, if the operator shop is equipped.

(4)优势

Benefit

空客SB系列A320-32-1522和A320-32-1523的完成将带来以下改进：

The accomplishment of the Airbus SBs A320-32-1522 and A320-32-1523 will introduce the following enhancements:

-引入了对同一起落架上NSV漂移的检测，因此取消了为缓解预EMM飞机因NSV漂移导致制动系统失效而发布的SB A320-32-1483检查要求。更多信息请参见ISI 32.42.00165。

-Introduces the detection of NSV drift on the same gear. Therefore, cancelling the need for inspection SB A320-32-1483, issued to mitigate the loss of braking system due to NSV drift on pre-EMM aircraft. Please refer to ISI 32.42.00165 for more information

-降低因刹车踏板偏移导致自动刹车系统意外脱开的风险。

-Reduces the risk of inadvertent autobrake disengagement due to brake pedal deflection.

-改善了解除刹车监控功能。

-Improves retraction braking monitoring.

改装过程

RETROFIT PROCEDURE

说明1：空客A320-32-1522 R01和A320-32-1523 R01机型提供了三种方案以完成服务公告。本RIL支持的改装活动仅涵盖其中两种方案，请见下文对应说明：

Note 1:Airbus SBs A320-32-1522 R01 and A320-32-1523 R01 propose three options to accomplish the Service Bulletins. The retrofit campaign supported by this RIL only covers two of these options, please find below the correspondence:

-SB 选项1-“通过更换飞机上的BSCU进行升级”：本次升级的完整BSCU不在本次活动范围内，因此不包含在此RIL中。

-SB OPTION 1 – “Upgrade by Replacement of BSCU on Aircraft”: the upgrade of the full BSCU is not within the scope of the campaign, therefore it is not included in this RIL.

-SB选项2-“根据VSB对BSCU OBRM进行重编程升级”：描述了本RIL中“内部重编程”的操作流程。

-SB OPTION 2 – “Upgrade by Reprogramming of BSCU OBRMs in accordance with VSB”: describes the procedure for “In-house reprogramming” in this RIL.

-SB选项3-“通过更换飞机上的BSCU OBRM进行升级”：描述了本RIL中“与供应商合作”程序。

-SB OPTION 3 – “Upgrade by Replacement of BSCU OBRMs on Aircraft”: describes the procedure for “Turnaround with vendor” in this RIL.

说明2：如果选择“内部重编程”，则BSCU OBRM单元的重编程责任由操作员承担。因此，此选项仅限于有权进入并配备有执行该升级的授权车间的操作员使用。

Note2:If "In-house reprogramming" is selected, the responsibility for reprogramming the BSCU OBRM units lies with the operator. Therefore, this option is reserved to operators with access to a shop that is authorized and equipped to perform this upgrade.

航材清单

LIST OF MATERIAL

内部重新编程

IN-HOUSE REPROGRAMMING

供应商合作

TURNAROUND WITH VENDOR