Issue No.:

Date:

System:

AED11/08-020 (Rev 1 dtd 12Oct15) Page 1 of 1

This EB is issued to remind maintenance personnel to follow AMM/MP tasks

PREPARED BY:

2021-09-0030 R00

13-Sep-21

AIRBUS/BOEING - ALL -

ATA 10ENGINEERING BULLETIN

APPROVED BY:

Noriel M. Purigay / ATS / SSTR / Ryan James C. Manuel / Mgr. / SSTR /

TITLE: PARKING IN HIGH WIND CONDITIONS

When aircraft is on the ground under high wind conditions especially when there is a typhoon,

correct aircraft configuration is required to ensure aircraft stability.

BACKGROUND:

when there is a typhoon or high wind conditions.

Printed Name / Position Title / Division / Signature

/A/ Airbus ISI 10.10.00003

/B/ Airbus ISI 10.10.00004

and thrust reverser to ensure aircraft stability.

4. Refer to below attachment for additional information:

Printed Name / Position Title / Division / Signature

OBJECTIVE:

MAIN CONTENT:

installed.

1. Make sure that the aircraft is parked on a flat surface and wheel chocks are properly

2. Observe the correct aircraft maintenance configuration of flight control surfaces

3. Once clear of the typhoon, return the aircraft to its initial configuration.

If aircraft is undergoing parking or storage procedure, refer to initial parking/storage

task for reference.

Aircraft Type AMM for Wheel Chocks Installation AMM for Aircraft Maintenance ConfigurationA320 10-11-00-555-015-A 05-57-00-200-001-A

A321CEO 10-11-00-555-015-A 05-57-00-200-001-B

A321NEO 10-11-00-555-015-A 05-57-00-200-001-B

A330 10-11-00-555-820-A 05-57-00-200-801-A

A350 A350-A-10-11-XX-03001-170A-A A350-A-05-57-XX-00001-177A-A

B777 10-11-03-860-801 10-11-03-860-801

Aircraft Parking and Storage under High Wind Conditions

Reference: 10.10.00003 Issue date: 29-JUL-2020 Last check date: 29-JUL-2020 Status: OpenA/C type/serie: A319, A320, A321 ATA: 05-57, 10-10, 10-20Engine manufacturer: Supplier: Purpose / Reason for revision: Additional Guidance Information to AMM.

Scheduled Maintenance Status: Open

Applicability:Out-of-operation A320FAM aircraft preserved IAW AMM task 10-10-00-550-801-A “Parking and Storage Procedure”

References:AMM task 05-51-42-200-001 “Inspection after Very High Winds on Ground”AMM task 05-57-00-200-001 “Aircraft Stability”AMM task 10-10-00-550-801 “Parking and Storage Procedure”AMM task 10-20-00-556-001 “Mooring of Aircraft without Weight and Balance Provision on the Landing Gear Legs”

BackgroundAircraft in parking or storage preservation shall be protected against shifting or tipping under high wind conditions. This document gives additional guidance and alternatives beyond the information in the AMM.

DescriptionThe AMM task 10-10-00-550-801 “Parking and Storage Procedure” para. 3.B.(3) states:“If the aircraft is parked or aircraft storage is in high wind conditions: Do a check of the aircraft stability Ref. AMM TASK 05-57-00-200-001. If necessary, moor the aircraft Ref. AMM TASK 10-20-00-556-001.” However, mooring points are not always present in the parking area or they might exist in insufficient numbers or at inappropriate positions to allow a straightforward application of the AMM procedure. This document provides additional information for the interpretation of AMM tasks 05-57-00-200-001 and AMM task 10-20-00-556-001 and describes possible alternatives to secure the aircraft against high wind impact.NOTE: It is recommended to also consult the ACI advisory bulletin “Mitigating the risks created by overflow aircraft parking”, which can be found in its

current revision under the following link: https://aci.aero/wp-content/uploads/2020/06/200603-Updated-Airfield-Parking-Advisory-Bulletin-FINAL.pdf.

Solution / Recommendation1. Aircraft Stability

AMM task 05-57-00-200-001 provides charts to determine under which conditions the aircraft will not be prone to shifting or tipping (with a minimum of 1500 kg load on the NLG).The wind speeds shown are indicating mean wind values and cover calculations done with +15 kts (29 km/h) gusts on top of the mean value. The friction coefficients used are 0.5 for dry ground and 0.3 for wet ground. These values are used to cover all types of surfaces in various level of contamination. As the locally effective friction coefficients may vary widely, operators may calculate with different values.

To achieve the maximum stability, weight can be added e.g. in the following ways, individually or combined: Ballast of 3 000 kg in the FWD cargo compartment. Ballast of 3 000 kg on the passenger deck, uniformly distributed from 8 m to 13.5 m to respect running load limitation of 767 kg/m. Filling the aircraft with 18 600 kg of fuel.NOTE: AMM task 10-10-00-550-801 para. 3.B.(5) “Make sure that the Trimmable Horizontal Stabilizer (THS) pitch-trim control-wheel is set to two degrees aircraft nose up” is not required for A320FAM aircraft; it will be removed from the AMM. Especially under high wind conditions, follow AMM task 05-57-00-200-001.

2. Mooring2.1 Standard Procedure: In case the weighing of the aircraft is not sufficient to assure the stability of the aircraft under the expected wind speeds, mooring is

required. Depending on the wind conditions (wind direction in relation to the position of the aircraft, wind speed and wind stability), mooring of the aircraft, if required, has to be done either at NLG only, or at both NLG and MLGs. Two different mooring tasks are existing in the AMM, depending on the configuration of the landing gear either equipped or not equipped with weight and balance provisions. The weight and balance provision was deleted by MOD 23007, validated in May 1994. It is therefore applicable to only very few aircraft and is not covered here. According to AMM task 10-20-00-556-001 “Mooring of Aircraft without Weight and Balance Provision on the Landing Gear Legs” the mooring is to be done at the NLG and the MLG by winding two round slings around the sliding tube and below the axles, and fixing them on four ground rings by means of hooks, rings, strap ratchets and shackles. This procedure includes a post mooring inspection of the gears. NOTE: Using slings fixed on the NLG lower drag-brace and the MLG’s side stays is not approved. Studies by Airbus have concluded that this could overstress

landing gear components or cause other damage.

Fig 1 Installation of mooring items on NLG Fig 2 Installation of mooring items on MLG Fig 3 Position of mooring points

2.2 Insufficient or wrongly placed mooring points: According to AMM task 10-20-00-556-001, each aircraft should be moored on the ground by 12 ground anchors. Nevertheless, not all airports or parking areas are equipped with this number of ground anchors. As shown in AMM figure reference 10-20-00-991-00500-02-A, which details the position of the ground rings for the MLG, Min and Max angles are defining the areas in which ground ring can be positioned.

Fig 1 Installation of mooring items on NLG Fig 2 Installation of mooring items on MLG

Fig 3 Position of mooring points

Fig 4 Ground master rings and possible strap directions

There is a minimum limit for the distance between the ground rings and the gear but there is no maximum limit for this distance. Therefore, alternate proposal to moor the aircraft with only 2 anchor points per gear can be proposed, using the anchor points of the other gears (ref. Fig 5). Having only two mooring anchors, aligned with each MLG, is not sufficient for proper mooring. However, they can be used together with additional points as shown in Fig 6a and 6b.Nevertheless, please be advised that airports anchors points are not standard. Therefore Airbus is not in position to confirm that the proposed alternate solutions will totally comply with AMM requirements in each case. As a consequence, customers should ensure that the angles and limitations defined in AMM task 10-20-00-556-001 are complied with on parking areas where aircraft are moored.

Concrete blocks

Not to scale

Fig 5 Mooring with 6 mooring points Fig 6a Detail of NLG mooring Fig 6b Use of 4 mooring points and additional concrete blocks

2.3 Alternative of concrete blocks: For aircraft on ground parked or in storage in areas, where anchor ground rings are not present, the following alternative can be proposed: Two concrete blocks with a mass of at least 2.5t each (represented as green rectangles on the sketch below) are positioned forward and aft of the NLG and of each MLG. Wood or rubber mats are fitted underneath the concrete blocks to increase the friction coefficient. For each gear, slings are looped around the sliding tube and below the axle as per AMM task, and fixed to these concrete blocks. Airbus technically concurs with concrete blocks (or others similar anchor means) being used as anchor points, provided that: The mooring of the gears is performed as required by AMM 10-20-00 (in particular the position of the ropes and the anchor rings is compliant with the

AMM requirements); It must be assured that no damage can be induced to the gear by any movement of the blocks (or other similar anchor means). The anchors points are positioned at ground level.

NOTE: If the anchors points cannot be positioned at ground level, then their exact location will have to be communicated, so that the potential impact on the loads introduced in the gears can be studied by Airbus.

Fig 7 Mooring with concrete blocks Fig 8 Example for concrete mooring block

2.4 Stopping lateral movement with concrete blocks for front-loaded aircraft: Vertical stability of the aircraft NLG may be achieved by use of ballast

and fuel. Wheel chocks are applied securely and the parking brakes are fully effective to prevent unwanted aircraft movement. NOTE: The park brake pressure depletes over time (~ 12 h). To maintain 100% braking, the accumulator may need to be replenished if the parking brake is

applied for long periods of time.In this above mentioned configuration, Airbus concurs to ensure full lateral stability of the aircraft by putting concrete blocks (or other similar anchor means) on each side of the NLG in contact with the wheels, to stop lateral movement with the following conditions: Put some protective material (e.g. sand bags) between the gear and the concrete blocks (or other similar anchor means), to avoid any direct contact and

damage on the gear and / or wheels; Ensure that only the tire sidewalls are loaded (no load applied on the wheel structure); Ensure that the concrete blocks (or other anchor means) have a sufficient height so that the load is applied on the full circumference of the tires; The NLG drag brace (or any other sprung component) must not be restrained by any form of strapping to allow free movement of the shock absorber.

3. InspectionAfter a high wind event, it is advised to consult AMM task 05-51-42-200-001 “Inspection after Very High Winds on Ground”.

Survey for the Scheduled Maintenance section

Annex

General InformationPotential impact:

Key information:

Solution benefit:

First issue date: 29-JUL-2020 Issue date: 29-JUL-2020 Last check date: 29-JUL-2020

Technical parametersATA: 05-57, 10-10, 10-20

A/C type/serie: A319, A320, A321

Engine:

Engine manufacturer:

Fault code/ECAM warning:

FIN:

Part Number:

Supplier:

Attachments N/A

Links N/A

© Airbus SAS, 2020. All rights reserved. Confidential and proprietary document.The technical information provided in this article is for convenience and information purposes only. It shall in no case replace the official Airbus technical or Flight Operations data which shall remain the sole basis for aircraft maintenance and operation. These recommendations and

information do not constitute a contractual commitment, warranty or guarantee whatsoever. They shall not supersede the Airbus technical nor operational documentation; should any deviation appear between this article and the Airbus or airline's official manuals, the operator must ensure to cover it with the appropriate document such as TA, FCD, RDAS.

Access to WISE is supplied by Airbus under the express condition that Airbus hereby disclaims any and all liability for the use made by the user of the information contained in WISE. It shall be used for the user's own purposes only and shall not be reproduced or disclosed to any third party without the prior consent of Airbus.

A330 Aircraft Parking and Storage under High Wind Conditions

Reference: 10.10.00004 Issue date: 10-NOV-2020 Last check date: 10-NOV-2020 Status: OpenA/C type/serie: A330 ATA: 05-57, 09-10, 10-10, ...Engine manufacturer: Supplier: Purpose / Reason for revision: Additional Guidance Information to AMM.

Scheduled Maintenance Status: Open

Applicability:

Out-of-operation A330 aircraft preserved IAW AMM task 10-10-00-555-801 “Parking and Storage Procedure”

References:

AMM task 05-51-42-200-801 “Inspection after Very High Winds on Ground”AMM task 05-57-00-200-801 “Aircraft Stability”AMM task 09-10-00-554-8XX “Towing by the Nose Landing Gear […]” AMM task 10-10-00-555-801 “Parking and Storage Procedure”AMM task 10-20-00-556-801 “Mooring of the Aircraft”Weight and Balance Manual (WBM)

Background

Aircraft in parking or storage preservation shall be protected against shifting or tipping under high wind conditions. This document gives additional guidance and alternatives beyond the information in the AMM.

Description

The AMM task 10-10-00-555-801 “Parking and Storage Procedure” para. 3.B.1.(3) states: “If the aircraft is parked in high wind conditions: Do a check of the aircraft stability Ref. AMM TASK 05-57-00-200-801. If necessary, moor the aircraft Ref. AMM TASK 10-20-00-556-801.” However, mooring points are not always present in the parking area or they might exist in insufficient numbers or at inappropriate positions to allow a straightforward application of the AMM procedure. This document provides additional information for the interpretation of AMM task 05-57-00-200-801 and AMM task 10-20-00-556-801 and describes possible alternatives to secure the aircraft against high wind impact.

NOTE: It is recommended to also consult the ACI advisory bulletin “Mitigating the risks created by overflow aircraft parking”, which can be found in its current revision under the following link: https://aci.aero/wp-content/uploads/2020/06/200603-Updated-Airfield-Parking-Advisory-Bulletin-FINAL.pdf.

Solution / Recommendation1 Aircraft Stability 1.1 Stability Limits:

AMM task 05-57-00-200-801 provides diagrams to determine under which conditions the aircraft will not be prone to shifting or tipping.The wind speeds shown are indicating mean wind speed values and cover calculations done with +15 kts (29 km/h) gusts on top of the mean value. The friction coefficients used are 0.5 for dry ground and 0.3 for wet ground. These values are used to cover all types of surfaces in various level of contamination. As the locally effective friction coefficients may vary widely, operators may calculate with different values.

1.2 Adding Ballast:To achieve the maximum stability, weight can be added in the form of ballast, individually or combined: Ballast of maximum 3 174 kg at ULD position 11 or 4 626 kg at ULD position 11P in the FWD cargo compartment. Ballast of maximum 3 174 kg at ULD position 12 or 4 626 kg at ULD position 12P in the FWD cargo compartment. Ballast of maximum 2 000 kg on the passenger deck at Frame 18, uniformly distributed. When adding ballast, the limits for the maximum load on the cabin floor, the maximum load on the FWD cargo compartment floor and the maximum load on the jacking points must not be exceeded. These limits are described in the Weight and Balance Manual (WBM) sections CTL-LIM-CAB-FLL, CTL-LIM-FWD-FLL and CTL-LIM-JACK.

1.3 Adding Fuel: Furthermore, weight can be added in the form of fuel, however this is normally quite limited: The AMM tasks 09-10-00-554-8XX “Towing by the Nose Landing Gear […]” all state in para. 1. “Reason for the Job”: “This procedure is for the towing of the aircraft in the maintenance configuration (Unloaded Aircraft). Operational towing (i.e. towing of an aircraft that contains passengers, fuel or cargo) from the terminal gate or parking area to a remote location is not permitted.” The aircraft weight for such a maintenance tow is therefore limited to the Operating Weight Empty (OWE) plus Fuel at Landing (FAL), where FAL is approximately 10% of the fuel tank capacity. The fuel weight required to achieve stability in high wind conditions or the fuel requirement for engine runs are typically higher than this limit. Airbus has therefore conducted an engineering study, which has just been concluded. The results permit during the exceptional parking and storage period induced by the global pandemic crisis to perform towing operations of an aircraft with a total aircraft weight up to a maximum of 75% of the Maximum Ramp Weight (MRW) = Maximum Taxi Weight (MTW); this allows for more than 50 000 kg of fuel on board, reduced by the amount of ballast installed. For the exact values for the specific A330 Weight Variant see the WBM. At this weight, up to 500 towing load applications are permitted on each aircraft. A towing load application is considered as a single movement, this can either be a pushback or forward start/stop. Each movement is considered as one load application.Some examples for scenarios which can be mixed providing the TOTAL number of load applications is not exceeded: 100 x short towing operations, consisting of up to 5 load applications (e.g. 1 pushback and 4 forward tow movements), or 50 x medium towing operations, consisting of up to 10 load applications (e.g. 1 pushback and 9 forward tow movements), or 25 x long towing operations, consisting of up to 20 load applications (e.g. 2 pushbacks and 18 forward tow movements). The towing activity must be performed in accordance with AMM task 09-10-00-584-802-A or AMM task 09-10-00-584-808-A.

Operators that want to apply this measure can request a Technical Adaptation (TA) from Airbus within the “Engineering” domain of TechRequest, ATA 09.

1.4 Trim Tank:The AMM task 10-10-00-555-801 para. 4.B.(2) states: “If necessary, refuel each fuel tank (wing tanks and trim tank) to have a minimum of 10% of their total capacity”. This is equivalent to ~ 500 kg of fuel in the trim tank. This requirement moves the Centre of Gravity (CG) rearward and increasing the risk of tipping. It is acceptable to empty the trim tank for a maximum 7 days. A fuel transfer from the trim tank to the inner tanks can therefore be performed in case of an expected high-wind condition.

1.5 THS Setting:The AMM task 10-10-00-555-801 para. 3.B.3.(4) states: “Make sure that the Trimmable Horizontal Stabilizer (THS) pitch-trim control-wheel is set to two degrees aircraft nose up”. While this is required to allow efficient water drainage, it can be waived for limited periods of high wind conditions. Readjust in such a case the THS setting as per AMM task 05-57-00-200-801 para. 3.A.(2).

Fig 1 Mooring Kit-98F10201000002

2 Mooring2.1 Standard Procedure:

The weight of the aircraft and the CG with ballast and fuel are calculated as per WBM and compared with the appropriate diagram in AMM task 05-57-00-200-801. In case the stability of the aircraft cannot be confirmed under the expected ground conditions and wind speeds, there is a need to moor the aircraft as per AMM task 10-20-00-556-801-A “Mooring of the Aircraft”. A Mooring Kit-NLG ref. 98F10201000000 (replaced by 98F10201000002) is to be installed between the towing fittings of the nose landing gear and the mooring point. This tool must be used vertically only and cannot be applied with non-aligned mooring points. No alternative tool for the mooring of the A330 NLG has been qualified.

Fig 2 Example for concrete mooring block

NOTE: If the anchors points cannot be positioned at ground level, then their exact location will have to be communicated, so that the potential impact on the loads introduced in the gears can be studied by Airbus.

2.3 Stopping lateral movement with concrete blocks for front-loaded aircraft:Assumption: Vertical stability of the aircraft NLG by use of ballast and fuel is confirmed, wheel chocks are applied securely and the parking brakes are fully effective to prevent unwanted aircraft movement. NOTE: The park brake pressure depletes over time (~ 12 h). To maintain 100% braking, the accumulator may need to be replenished if the parking brake is

applied for long periods of time.In this above mentioned configuration, Airbus concurs to ensure full lateral stability of the aircraft by putting concrete blocks (or other similar anchor means) on each side of the NLG in contact with the wheels, to stop lateral movement with the following conditions: Put some protective material (e.g. sand bags) between the gear and the concrete blocks (or other similar anchor means), to avoid any direct contact and

damage on the gear and / or wheels; Ensure that only the tire sidewalls are loaded (no load applied on the wheel structure); Ensure that the concrete blocks (or other anchor means) have a sufficient height so that the load is applied on the full circumference of the tires; The NLG drag brace (or any other sprung component) must not be restrained by any form of strapping to allow free movement of the shock absorber.

3 InspectionAfter an event with a wind speed of more than 80 knots (150 km/h), an inspection in accordance with AMM task 05-51-42-200-801 “Inspection after Very High Winds on Ground” shall be performed.

Survey for the Scheduled Maintenance section

2.2 Missing or wrongly placed mooring points: Airports anchors points are not standardized and the mooring point geometry as described in AMM 10-20-00 differs between e.g. the A320FAM and the A330 programme. If it is not possible / allowed to off-set the axis of the aircraft to bring the NLG aligned with the mooring point, as an alternative, Airbus technically concurs with a concrete block (or others similar anchor means) being used as anchor points under the following conditions: The concrete block(s) has/have a mass of at least 9 000 kg, positioned

forward of the NLG. Wood or rubber mats are fitted underneath the concrete block to

increase the friction coefficient. It must be assured that no damage can be induced to the gear by any

movement of the block (or other similar anchor means). The anchors points are positioned at ground level.

Annex

General InformationPotential impact:

Key information:

Solution benefit:

First issue date: 10-NOV-2020 Issue date: 10-NOV-2020 Last check date: 10-NOV-2020

Technical parametersATA: 05-57, 09-10, 10-10, 10-20

A/C type/serie: A330

Engine:

Engine manufacturer:

Fault code/ECAM warning:

FIN:

Part Number:

Supplier:

Attachments N/A

Links N/A

© Airbus SAS, 2020. All rights reserved. Confidential and proprietary document.The technical information provided in this article is for convenience and information purposes only. It shall in no case replace the official Airbus technical or Flight Operations data which shall remain the sole basis for aircraft maintenance and operation. These recommendations and

information do not constitute a contractual commitment, warranty or guarantee whatsoever. They shall not supersede the Airbus technical nor operational documentation; should any deviation appear between this article and the Airbus or airline's official manuals, the operator must ensure to cover it with the appropriate document such as TA, FCD, RDAS.

Access to WISE is supplied by Airbus under the express condition that Airbus hereby disclaims any and all liability for the use made by the user of the information contained in WISE. It shall be used for the user's own purposes only and shall not be reproduced or disclosed to any third party without the prior consent of Airbus.