Maintenance manual. Flight helmet LA100 PP

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Transcription:

Flight helmet LA100 PP010298-00

Table of Contents Page Table of Contents 1/21 - Warning notice 2/21 - Helmet description 3/21 - Introduction 4/21 1 Chinstrap 5/21 2 Inner liner elements 6/21 3 Edge roll 7/21 4 Inner visor 8/21 5 Outer visor 9/21 6 NVG hard cover 10/21 7 Earphones and hygiene parts of the ear cups 11/21 8 Oxygen mask receiver 12/21 General information 13/21 Inspection testing and maintenance table 13/21 Mandatory inspections and replacement criteria 14 to 21/21 1

WARNING NOTICE Thank you for putting your trust in MSA products. Read these instructions carefully before using your helmet. Failure to follow these instructions could reduce the level of protection provided by your helmet. The level of protection provided by the helmet is only guaranteed if it has all the original MSA parts. Therefore, any modifications made to your helmet or the absence of any of the parts forming the original helmet will make the equipment supplied non-compliant, releasing MSA from all liability. In order to keep improving its products, MSA reserves the right to modify them without prior notice. To provide sufficient protection, this helmet must be fitted and adjusted to the head size of its wearer. The helmet is made in such a way that any energy received during an impact is absorbed by the destruction of or partial damage to the shell and impact cap; even if this damage is not immediately apparent, replacement of the whole helmet is recommended after a major impact. Users' attention is also drawn to the danger of modifying or removing any of the original parts of the helmet except where the modification or removal is recommended by the helmet manufacturer. Under no circumstances should helmets be adapted so that accessories can be attached using a process not recommended by the helmet manufacturer. Do not apply paints, solvents, adhesives or stickers, except those recommended by the helmet manufacturer's instructions. After any obvious impact an inspection should be carried out by the maintenance department or specialist workshop. 2 The MSA LA100 flight helmet is designed solely for fixed wings pilots and flight crew equipped with oxygen and ejection seat, It provides maximum comfort and protection. It is available in two sizes, covering head circumferences from 52 cm to 64 cm. It has two visors and can be fitted with a wide range of communication systems, on request. Contact us for more details. Traceability is assured by a label showing a serial number.

FLIGHT HELMET LA100 HELMET DESCRIPTION Description: The shell of the helmet consists of: - an outer shell made from high performance composites, - an expanded polystyrene impact cap to absorb shocks, covered with an inner liner. The inner liner consists of a T-shaped comfort liner and a neck pad. The helmet is adapted to the shape of the wearer's head by personalising the T-shaped comfort liner and the neck pad and the adjustment pads for adjusting the pressure of the ear cups on the ears. The helmet has 2 protective visors, an inner visor and an outer visor. The ear protection system consists of: - two ear cups, containing a housing for installing the earphones. - two ergonomic comfort ear seals. The ear cups provide excellent ear protection and are fixed inside the shell by means of hook and loop pads. The helmet chinstrap is adjustable and fully removable. Every helmet is supplied with a protective bag and a personalisation kit. The helmet can be equipped with oxygen racks accommodate allowing the wear of oxygen mask, a wide range of communication systems and night vision goggle fittings, on request. WARRANTY 3 All models, accessories and spares are subject to stringent checks before leaving the factory. MSA helmets and accessories are guaranteed for 12 months, parts and labour, from the date of delivery to the buyer, against any failure during use under the conditions described in this manual. You also have a statutory warranty against hidden faults and defects subject to the conditions laid down in Articles 1641 ff. of the French Civil Code.

INTRODUCTION Important: whenever you are handling the helmet, make sure you put it down on its carry bag. Tools required: - 7 mm flat spanner - 2 mm hexagonal screwdriver - Flat screwdriver 4 - Philips screwdriver

1. Chinstrap: Tools: Philips screwdriver. Dismantling duration: 15 seconds. Mounting duration: 30 seconds. The chinstrap is secured to the helmet by means of two screws on the left chinstrap bracket. To remove the chinstrap, unscrew the screws on the left side, then take out the chinstrap levers by holding them by the ends. To reinstall, engage each lever, making sure the chin cup is the right way round (the return part of the strap should be uppermost) and so are the levers. Lock by pressing in the middle of the lever. Tighten the 2 screws. You do not have to remove the chinstrap in order to take off the chin cup. Important: when reinstalling, the screws should be tightened 1/8 of a turn from when the tightening stress increases (screwing into plastic). Screws securing the chinstrap 5

Maintenance manual 2. Inner liner elements: Tools: None. Dismantling duration: 20 seconds. Mounting duration: 45 seconds. There are three inner liner elements: The comfort liner with its interchangeable foam pieces, each supplied in 3 thicknesses (4, 8 and 12 mm thick), The neck pad (XS, S and M or L, XL and XXL depending on the helmet size), The ear cups and their adjustment pads (3 on each side + 2 extra on each side), The comfort liner is adjustable in 4 areas with 3 possible thicknesses (N.B. When replacing the foam pieces, check that they are seated correctly). The neck pad is also supplied in 3 different thicknesses. The liner elements are fixed to the impact cap and shell with hook and loop tape, so no tools are needed. N.B. Be careful not to break the polystyrene core of the neck pad during removal or reinstallation. The audio cables must run between the edge roll and the neck pad (see audio cable section). 6

3. Edge roll Tools: None. Dismantling duration: 20 seconds. Mounting duration: 45 seconds.. The edge roll is replaceable. It is attached to the rim by means of press studs (3 on each side) and adjusts to fit the shell by means of two fastening pins. No tools are needed for its removal and reinstallation. When removing the edge roll, it is best to take out the ear cups and the neck pad first. Then detach the 6 press studs and remove the 3 pins. When removing the first pin, it is important to twist the edge roll then slide the pin along its slot. The second pin will then come out easily on its own. To reinstall the edge roll, engage the pins one after the other in the slots, then fasten the press studs. 7

4. Inner visor: Tools: None. Removal time: 15 seconds. Reinstallation time: 30 seconds. The inner visor is attached to its rotation system by means of clips. Move the visor to the lowered position. Important: the direction of removal of the inner visor is perpendicular to the 2 rivets of the visor attachments. To reinstall it, check that the control levers of the inner visor are in the lowered position. Engage the visor so that the clips will go into their housings correctly. Clip in by pressing on the ends of the visor. Rotation system in lowered position Reinstallation: Insert the clips into their housings and push to clip the visor in place Removal: Pull the visor at a right angle to the 2 rivets 8

5. Outer visor: Tools: 2 mm hexagonal screwdriver, Philips screwdriver. Removal time: 2 minutes. Reinstallation time: 2 minutes. Remove the hard cover (see section 6). Unscrew the 2 small BLACK M2, 2x6 TF POZIDRIV screws at the front. Lower the visor so that you can remove the outer visor guide assembly from the rail. Then pull the left and right guide systems away from the helmet. 9 For reassembly, perform the same operations in reverse. Warning When you are reinstalling the hard cover, check that the pin is correctly positioned in the base. Tighten the STAINLESS STEEL M3X8 TF HC screws on the right and left.

6. NVG hard cover: Tools: None Removal time: 10 seconds. Reinstallation time: 30 seconds. Release the side hooks of the hard cover left and right simultaneously and switch the hard cover backward. For reassembly, perform the same operations in reverse. Align cover pins in pinholes located on the helmet. 10 Warning When you are reinstalling the hard cover, check that the pin is correctly positioned in the base.

7. Earphones and hygiene parts of the ear cups: Tools: 5.5 mm (box or flat) spanner Dismantling duration: 3 minutes. Mounting duration: 4 minutes. To remove the earphones, take out the ear cups. For each ear cup: Remove the fabric seal. Remove the 2 acoustic foam pieces Pull the earphone cable away for easier access. 11 Unscrew the 2 nuts from the terminals. (Keep the nuts, etc.) Remove the 3 connectors. To reassemble, proceed in the reverse order.

8- Oxygen mask receiver: Tools: 2 mm hexagonal screwdriver, Philips screwdriver. Removal time: 2 minutes. Reinstallation time: 2 minutes. - take out the left and right ear cups; - Unscrew the rear countersunk head screw with the black washer inside the shell; - Unscrew two button head screws with their two washers (one black + one star washer each) inside the shell. To reassemble, proceed in the reverse order. Important : during reassemble, the rear countersunk head screw must tighten one-eighth turn as soon as the clamping force increases (tightening in plastic material). button head screws, flat washer and star washer 12 rear countersunk head screw with the black washer

GENERAL INFORMATION This section concerns the tests and inspections required to determine the condition of any units withdrawn from service. Dispose of any defective parts. All defective parts should be disposed of and replaced with new parts from MSA only. All tests should be carried out on clean parts (see section on cleaning). Inspection, testing and maintenance table: Basic checks* Pre-flight Visors cleanliness and operation yes Presence and secure attachment of comfort elements yes (comfort liner, neck pad, edge roll) Condition of chinstrap and attachment points, operation of buckle yes Communication system test yes Attachment of hard cover yes Shell and hard cover (no cracks, no dents, aramid and carbon yes not visible, screws and inserts in their housings) General condition of helmet yes Periodic checks* Frequency Shell condition: particularly adhesion of chinstrap mounts, slight impacts 3 months due to normal use Condition of impact cap and rim: in particular adhesion of impact cap to rim 3 months Attachment of impact cap to shell 3 months Secure attachment and operation of visors on their bases, communication 3 months system, cable protector Condition and operation of visors and their attachment system 3 months Condition of comfort liner pads 3 months Condition of inner liner elements and ear cups 3 months Condition of chinstrap and fastening buckle 3 months Operation of chinstrap locking system 3 months Operation of communication system (with inspection of cable condition) 3 months Check that all screws are tight 3 months Check the play of moving sub-assemblies during operation 3 months Cleaning (in accordance with the instructions given in the user manual) 3 months Recommended replacement of main parts* Frequency Inner visor 5 years Outer visor 5 years Edge roll 2 years Comfort liner and neck pad 2 years Chinstrap attachment assembly 2 years Chinstrap 2 years Comfort ear seals 2 years LH 250 chinstrap assembly 2 years Impact cap 15 years Shell 15 years *: based on normal use of 200 hours per year and depending on the condition of the part. 13

MANDATORY INSPECTIONS AND REPLACEMENT CRITERIA This section explains the mandatory action to be taken and the inspections necessary when a helmet has suffered an impact OR when maintenance reveals damage caused by an impact. See criteria appendices. The mandatory action and necessary inspections are explained in the table below. ACTION TO BE TAKEN The helmet shell is designed to protect against a single impact. The integrity of the shell is considered to have been compromised after an impact. The shell of a helmet that has suffered an impact must be destroyed and replaced. Mandatory inspection Where damage caused by the impact is found. The helmet must be inspected to check for Dents, cracking or deformation of the composite fibres in the shell or hard cover; Damage to the composite shell consisting of composite fibres that have been cut or shredded; Removal of the outer coating leading to damage to the gel coat layer and exposure of the composite fibres; Movement of the impact cap; Damage to the visors and the visor movement mechanisms; Damage to the chinstraps at the chinstrap anchor points and the fastening buckle; The inspection must be recorded on the equipment monitoring sheet. If the inspection confirms an impact, the shell and the impact cap must be replaced. Condition Impact: IMPACT CONFIRMED Suspected impact: Mandatory inspections if an impact is suspected 14 User and maintenance workshop All helmet users and maintenance units are responsible for reporting known or suspected impacts and damage to helmets. MSA will not be held responsible for failure to remove from service a shell that has been damaged or has suffered an impact. Only MSA distributor is authorized to remove the impact cap. In case of doubt about the integrity of the impact cap or the shell, contact your MSA distributor.

APPENDICES: Replacement criteria - LH 250 PM and GM shell and fittings Sub-elements - Defects Criteria - Action Aramid fibres Cracks and/or damaged* Replace Shell scratches Aramid fibres not damaged* Nothing to report Impacts Height of fall > 1 m Replace Height of fall < 1 m Nothing to report Riveting Defective Replace Rail Attachment Coming apart Replace Breakage Defective Replace Wear Defective Replace Riveting Defective Replace Chinstrap mount Attachment Coming apart Replace Breakage Defective Replace Wear Defective Replace Edge seals Attachment Coming apart Rebond with glue. 15

Cosmetic defects (paint scratches, etc.) do not require replacement of the shell. Paint scratch Scratch to paint and gel coat but no damage to aramid or carbon. Defect where the aramid and/or carbon are showing The appearance of aramid and/or carbon filaments means Deep scratch affecting the aramid (yellow) or carbon (black) in the shell. 16 Hole following an impact revealing the aramid (yellow) or carbon (black) in the shell.

Cracks with or without replacement of the shell If a helmet has one or more paint cracks on the outside and white marks (delamination of the aramid) on the inside, the shell must be replaced. Impacts Warning: cracked paint can signal an impact or that the shell has been tightly squeezed; in this case the impact cap must be removed to check the condition of the aramid inside the shell. If a helmet has one or more traces of impacts on the outside and white marks (delamination of the aramid) on the inside, the shell must be replaced. Specific traces of an impact inside the shell: concentric white lines matching the cracks on the outside. 17 Paint Gelcoat Resin Carbon fibre The appearance of carbon filaments in the area where the visor mechanism is located means that the shell must be replaced.

Complete PM and GM aviation impact caps The impact cap/rim assembly must be replaced in the following cases - deformed impact cap, - impact cap unstuck from its rim, - rim showing white marks. Sub-elements Defects Criteria - Action Rim Impact cap Inner liner Press stud White mark on the carbon Part close to leather + rayon** Nothing to report Breakage Defective Replace Weld Crack Replace Attachment Coming apart Replace Deformation Defective Replace Breakage Defective Replace Attachment Coming apart Replace Crimping Excessive play or missing Replace part near leather + rayon 18 Examples of white marks on the carbon rim of the impact cap.

PM and GM inner visor assembly Zones on inner visor: PM and GM outer visor assembly Zones on outer visor: 19

Zone Defects Criteria Action Spots of paint Ø 0.1 mm Quantity > 3 Replace part Spots of paint Ø > 0.1 mm Quantity = 0 Replace part Zone 1 Scratches: length < 5 mm, Quantity > 8 Replace part depth < 0.05 mm Spots of paint 0.1 mm < Ø < 0.2 mm Quantity > 5 Replace part or Black spots 0.1 mm < Ø < 0.2 mm Quantity = 2 Replace part Zones 2 and 3 or Scratches: length < 5 mm; Quantity > Replace part depth < 0.05 mm 16 Zone 4 All None Sub-elements Defects Criteria Action Coming apart Minor Nothing to report Velcro hooks Coming apart Major Replace part Lateral interfaces Riveting Excessive play or missing Replace part Lateral interface Breakage Defective Replace part Visor inserts Coming loose Defective Replace part Spring stuck Operation of hooks Outer visor guide or lost Replace sub-assembly Slider Defective Replace sub-assembly Inner visor rotation tests It must be possible to rotate the visor using either of the knobs with one hand (thumb/index finger). N.B.: The two screws holding in place the inner visor controls should be tightened 1/8 turn from when the tightening stress increases, with the 2 mm hex screwdriver. 20 Outer visor locking tests Starting from the raised position, the visor is locked and unlocked in the lowered positions

Chinstrap assembly Sub-elements Defects Criteria Action Locking clip Play Free Replace chinstrap assembly or locking clip Replace chinstrap Chinstrap lever Crack Defective assembly or chinstrap or scale attachment Strap Stitching Defective Replace chinstrap assembly or strap Screw Missing Defective Replace chinstrap assembly or screw Strap Wear Defective Replace chinstrap assembly or strap Keeper Wear Defective Replace chinstrap assembly or keeper 21