Airworthiness Manual Chapter 522 Subchapter D - Design and Construction - Canadian Aviation Regulations (CARs)

Content last revised: 2010/12/01


  • A (522.1-522.3)
  • B (522.21-522.255)
  • C (522.301-522.597)
  • D (522.601-522.885)
  • E (522.901-522.1193)
  • F (522.1301-522.1449)
  • G (522.1501-523.1589)
  • H (522.1801-523.1857)
  • J (522.1901-523.1947)


F, G, I, J, K


Subchapter D - Design and Construction

522.601 General

The suitability of each questionable design detail and part having an important bearing on safety in operations must be established by test.

522.603 Materials

The suitability and durability of materials used for parts, the failure of which could adversely affect safety, must -

  • (a) be established by experience or tests; and

  • (b) meet approved specifications that ensure their having the strength and other properties assumed in the design data.

522.605 Fabrication Methods

The methods of fabrication used must produce consistently sound structures. If a fabrication process (such as gluing, spot welding, heat-treating, or processing of plastic materials) requires close control to reach this objective, the process must be performed under an approved process specification.

522.607 Locking of Connections

An approved means of locking must be provided on all connecting elements in the primary structure and in control and other mechanical systems which are essential to safe operation of the glider. In particular self-locking nuts may not be used in any bolt subject to rotation in operation, unless a non-friction locking device is used in addition to the self-locking device.

522.609 Protection of Structure

Each part of the structure must

  • (a) be suitably protected against deterioration or loss of strength in service due to any cause, including

    • (1) weathering;

    • (2) corrosion; and

    • (3) abrasion; and

  • (b) have adequate provisions for ventilation and drainage.

522.611 Accessibility

Means must be provided to allow:
(amended 2000/11/25)

  • (a) inspection of principal structural elements and control systems;
    (amended 2000/11/25)

  • (b) replacement of parts normally requiring replacement; and
    (amended 2000/11/25)

  • (c) adjustment and lubrication as necessary for continued airworthiness.
    (amended 2000/11/25)

The means of inspection must be practicable for the inspection intervals established for the item during certification. This must be stated in the Maintenance Manual required under 522.1529.
(amended 2000/11/25)

522.612 Provisions for Rigging and De-rigging

The design of the glider must be such that during rigging and derigging by untrained persons, the probability of damage or permanent deformation, especially when this is not readily visible, is extremely remote. Incorrect assembly must be avoided by proper design provisions.

It must be possible to inspect the glider easily for correct rigging.

522.613 Material Strength Properties and Design Values

  • (a) Material strength properties must be based on enough tests to establish design values on a statistical basis.

  • (b) The design values must be chosen so that the probability of any structure being understrength because of material variations is extremely remote.

  • (c) Where the temperature attained in an essential component or structure in normal operating conditions has a significant effect on strength, that effect must be taken into account.

522.619 Special Factors

  • (a) The factor of safety prescribed in 522.303 must be multiplied by appropriate combinations of the special factors prescribed in 522.621 through 522.625, 522.657, 522.693 and 522.619(b).

  • (b) For each part of the structure not covered by 522.621 through 522.625, 522.657 and 522.693 but whose strength is

    • (1) uncertain;

    • (2) likely to deteriorate in service before normal replacement; or

    • (3) subject to appreciable variability because of uncertainties in manufacturing processes or inspection methods; the special factor must be chosen so that failure of the part due to inadequate strength is improbable.

522.621 Casting Factors

For castings the strength of which is substantiated by at least one static test and which are inspected by visual methods, a casting factor of 2.0 must be applied. This factor may be reduced to 1.25 providing the reduction is substantiated by tests on not less than three sample castings and if these and all production castings are subjected to an approved visual and radiographic inspection or an approved equivalent non-destructive inspection method.

522.623 Bearing Factors

  • (a) The factor of safety for bearings at bolted or pinned joints must be multiplied by a special factor of 2.0 to provide for:

    • (1) relative motion in operation; and

    • (2) joints with clearance (free fit) subject to pounding and/or vibration.

  • (b) For control surface hinges and control system joints, compliance with the factors prescribed in 522.657 and 522.693, respectively, meets subparagraph (a) of this paragraph.

522.625 Fitting Factors

For each fitting (a part or terminal used to join one structural member to another), the following apply:

  • (a) For each fitting whose strength is not proven by limit and ultimate load tests in which actual stress conditions are simulated in the fitting and surrounding structures, a fitting factor of at least 1.15 must be applied to each part of -
    (amended 2007/07/16)

    • (1) the fitting;

    • (2) the means of attachment; and

    • (3) the bearing on the joined members.

  • (b) No fitting factor need be used for joint designs based on comprehensive test data (such as continuous joints in metal plating, welded joints,and scarf joints in wood).

  • (c) For each integral fitting, the part must be treated as a fitting up to the point at which the section properties become typical of the member.

  • (d) For each seat, safety belt, and harness, its attachment to the structure must be shown, by analysis, tests,or both, to be able to withstand the inertia forces prescribed in 522.561 multiplied by a fitting factor of 1.33.

  • (e) When using only two hinges at each control surface, or wing-flap, the safety factor for these hinges and the attached parts of the primary structure must be multiplied by a factor of 1.5.

522.627 Fatigue Strength

The structure must be designed, as far as practicable, to avoid points of stress concentration where variable stresses above the fatigue limit are likely to occur in normal service.

522.629 Flutter

  • (a) The glider must be free from flutter, aerofoil divergence, and control reversal in each configuration and at each appropriate speed up to at least VD. Sufficient damping must be available at any appropriate speed so that aeroelastic vibration dies away rapidly.

  • (b) Compliance with subparagraph (a) must be shown by:

    • (1) a ground vibration test which includes an analysis and an evaluation of the established vibration modes and frequencies for the purpose of recognizing combinations critical for flutter, either by:

      • (i) an analytical method, which will determine any critical speed in the range up to 1.2 VD, or

      • (ii) any other approved method.

    • (2) systematic flight tests to induce flutter at speeds up to VDF. These tests must show that a suitable margin of damping is available and that there is no rapid reduction of damping as VDF is approached.

    • (3) Flight tests to show that when approaching VDF:

      • (i) control effectiveness around all three axes is not decreasing in an unusually rapid manner, and

      • (ii) no signs of approaching aerofoil divergence of wings, tail-plane and fuselage result from the trend of the static stabilities and trim conditions.

Control Surfaces

522.655 Installation

  • (a) Movable control surfaces must be installed so that there is no interference between any surfaces or their bracings when one surface is held in any position and the others are operated through their full angular movement. This requirement must be met:

    • (1) under limit load (positive or negative) conditions for all control surfaces through their full angular range; and

    • (2) under limit load on the glider structure other than control surfaces.

  • (b) If an adjustable stabilizer is used, it must have stops that will limit its range of travel to that allowing safe flight and landing.

522.657 Hinges

  • (a) Control surface hinges, except ball and roller bearing hinges, must have a factor of safety of not less than 6.67 with respect to the ultimate bearing strength of the softest material used as a bearing.

  • (b) For ball or roller bearing hinges, the approved rating of the bearing may not be exceeded.

  • (c) Hinges must have enough strength and rigidity for loads parallel to the hinge line.

522.659 Mass Balance

The supporting structure and the attachment of concentrated mass balance weights used on control surfaces must be designed for

  • (a) 24 g normal to the plane of the control surface;

  • (b) 12 g fore and aft; and

  • (c) 12 g parallel to the hinge line.

Control Systems

522.671 General

Each control must operate easily, smoothly, and positively enough to allow proper performance of its functions.

522.675 Stops

  • (a) Each control system must have adjustable stops that positively limit the range of motion of each movable aerodynamic surface controlled by the system.

  • (b) Each stop must be located so that wear, slackness, or take up adjustments will not adversely affect the control characteristics of the glider because of a change in the range of surface travel.

  • (c) Each stop must be able to withstand any loads corresponding to the design conditions for the control system.

522.677 Trim System

  • (a) Proper precautions must be taken to prevent inadvertent, improper, or abrupt trim tab operation. There must be means near the trim control to indicate to the pilot the direction of trim control movement relative to glider motion. In addition, there must be means to indicate to the pilot the position of the trim device with respect to the range of adjustment. This means must be visible to the pilot and must be located and designed to prevent confusion.

  • (b) Tab controls must be irreversible unless the tab is properly balanced and has no unsafe flutter characteristics.

Irreversible tab systems must have adequate rigidity and reliability in the portion of the system from the tab to the attachment of the irreversible unit to the glider structure.

522.679 Control System Locks

If there is a device to lock the control system on the ground, there must be means to -

  • (a) give unmistakable warning to the pilot when the lock is engaged; and

  • (b) prevent the lock from engaging in flight.

522.683 Operation Tests

It must be shown by functional tests that the system designed to the loads specified in 522.397 is free from:

  • (a) jamming;

  • (b) excessive friction; and

  • (c) excessive deflection;

when operating the controls from the cockpit.

522.685 Control System Details

  • (a) Each detail of each control system must be designed and installed to prevent jamming, chafing, and interference from baggage, passengers, loose objects, or the freezing of moisture.

  • (b) There must be means in the cockpit to prevent the entry of foreign objects into places where they would jam the system.

  • (c) There must be means to prevent the slapping of cables or rods against other parts.

  • (d) Each element of the flight control system must have design features, or must be distinctively and permanently marked, to minimize the possibility of incorrect assembly that could result in malfunctioning of the control system.

  • (e) In gliders certificated for aerobatic manoeuvres, where necessary the rudder pedals must be provided with loops to prevent the feet from slipping off the pedals.

522.687 Spring Devices

The reliability of any spring device used in the control system must be established by tests simulating service conditions unless failure of the spring will not cause flutter or unsafe flight characteristics.

522.689 Cable Systems

  • (a) Each cable, cable fitting, turnbuckle, splice, and pulley used must meet approved specifications. In addition

    • (1) no cable smaller than 3 mm diameter may be used in primary systems;

    • (2) each cable system must be designed so that there will be no hazardous change in cable tension throughout the range of travel under operating conditions and temperature variations; and

    • (3) there must be means for visual inspection at each fairlead, pulley, terminal, and turnbuckle. The need for this requirement may be waived when it can be shown that airworthiness will not be affected within the service life of these components.

  • (b) Each kind and size of pulley must correspond to the cable with which it is used. Each pulley must have closely fitted guards to prevent the cables from being misplaced or fouled, even when slack. Each pulley must lie in the plane passing through the cable so that the cable does not rub against the pulley flange.

  • (c) Fairleads must be installed so that they do not cause a change in cable direction of more than 3°, except where tests or experience indicate that a higher value would be satisfactory. The radius of curvature of fairleads must not be smaller than the radius of a pulley for the same cable.

  • (d) Turnbuckles must be attached to parts having angular motion in a manner that will positively prevent binding throughout the range of travel.

  • (e) Tab control cables are not part of the primary control system and may be less than 3 mm diameter in gliders that are safely controllable with the tabs in the most adverse positions.

522.693 Joints

Control system joints (in push-pull systems) that are subject to angular motion, except those in ball and roller bearing systems, must have a special factor of safety of not less than 3.33 with respect to the ultimate bearing strength of the softest material used as a bearing. This factor may be reduced to 2.0 for joints in cable control systems. For ball or roller bearings, the approved ratings may not be exceeded.

522.697 Wing-flap and Air-brake Controls

  • (a) Each wing-flap control must be designed so that, when the wing-flap has been placed in any position upon which compliance with the performance requirements of this Chapter is based, the wing-flap will not move from that position except when:

    • (1) the control is adjusted; or

    • (2) the wing-flap is moved by the automatic operation of a wing-flap load limiting device; or

    • (3) movement other than in accordance with (1) or (2) is demonstrated not to be hazardous.

  • (b) Each wing-flap and air brake must be designed to prevent inadvertent extension or movement. The pilot forces and the rate of movement at any approved flight speed must not be such as to impair the operating safety of the glider.

  • (c) The air brake or other drag increasing device necessary to show compliance with 522.73 and/or 522.75 must comply with the following:

    • (1) Where the device is divided into several parts, all parts must be operated by a single control.

    • (2) It must be possible to extend the device at any speed up to 1.05 VNE and to retract the device at any speed up to VT, but not less than 1.8 VS1, with a hand force not exceeding 20 daN.
      (amended 2007/07/16)

    • (3) The time required for extension as well as retraction of the device may not exceed 2 seconds.

(Change 522-1 (87-08-31))

522.699 Wing-flap Position Indicator

There must be means near the wing-flap control to indicate to the pilot the position of the wing-flaps during and after operation.

522.701 Wing-flap Position Indicator

The motion of wing-flaps on opposite sides of the plane of symmetry must be synchronized by a mechanical interconnection unless the glider has safe flight characteristics with the wing-flaps retracted on one side and extended on the other.

522.711 Release Mechanisms

  • (a) Release mechanisms to be used for winch-launching must be so designed and installed as to release the towing cable automatically (i.e. to back-release) if the glider overruns the cable while it is carrying any appreciable load.

  • (b) The release mechanisms must be approved.

  • (c) It must be extremely improbable for bolts or other projections on the release mechanism itself or the structure surrounding the mechanism, including the landing gear, to foul the towing cable or its parachute.

  • (d) It must be shown that the release force will not exceed that prescribed in 522.143(c) when a cable load Qnom is applied in any direction (see 522.583), and that the release mechanism functions properly under any operating condition.
    (amended 2007/07/16)

  • (e) The range of travel of the release lever in the cockpit, including free travel, must not exceed 120 mm.

  • (f) The release lever in the cockpit must be arranged and designed so that the pilot force as defined in 522.143(c) can be easily applied.

  • (g) A visual inspection of the release mechanism must be easily possible.

522.713 Launching Hook

Depending on the launching method(s) for which certification is requested, the glider must be fitted with one or more launching hooks complying with the following:

  • (a) Each hook to be used for aerotow launching must be

    • (1) Designed to minimise the possibility of inadvertant release, and;

    • (2) Installed to minimise the possibility of dangerous upsets during aerotowing (see 522.151(a)(3) and to produce a nose-down pitching moment on the glider under the conditions of 522.581 (a)(3), but with an angle of not more than 25°.
      (amended 2007/07/16)

  • (b) Each hook to be used for winch and/or auto-tow launching must be equipped with a release device which is automatically activated when the glider overflies the towing winch or auto-tow vehicle.

  • (c) The release control system must be designed to actuate the release mechanism of each launching hook at the same time, where more than one launching hook is fitted.

(Change 522-2 (93-06-30))

Landing Gear

522.721 General

  • (a) The glider must be so designed that it can land on unprepared soft ground without endangering its occupants.

  • (b) Each glider fitted with retractable landing gear must be designed and constructed so that normal landings with the landing gear retracted are possible.

  • (c) The design of wheels, skids and tail skid and their installation must be such as to minimize the possibility of fouling by the towing cable.

  • (d) If the main landing gear consists only of one or more wheels, the glider must be equipped with mechanical braking devices, such as wheel brakes.

  • (e) A shock-absorbing element must be fitted to the tail skid.

522.723 Shock Absorption Test

The proof of sufficient shock absorption capacity must be determined by test. The landing gear must be able to absorb 1.44 times the energy described in 522.473 without failure although it may yield during the test.
(amended 2007/07/16)

522.725 Level Landing

  • (a) The shock absorbing elements (including tires) must be capable of absorbing the kinetic energy developed in a landing without being fully depressed.

  • (b) The value of kinetic energy must be determined under the assumption that the weight of the glider corresponds to the design maximum weight with a constant rate of descent equalling the value given in 522.473(b) and the wing lift balancing the weight of the glider.
    (amended 2007/07/16)

  • (c) Under the assumption of (b) the c.g. acceleration must not exceed 4.5 g.
    (amended 2007/07/16)

(Change 522-1 (87-08-31))

522.729 Retracting Mechanism

  • (a) Each landing gear retracting mechanism and its supporting structure must be designed for the maximum flight load factors occurring with the gear retracted.

  • (b) For retractable landing gears it must be shown that extension and retraction of the landing gear are possible without difficulty up to VLO.
    (amended 2007/07/16)

  • (c) A glider equipped with a non-manually operated landing gear must have an auxiliary means of extending the gear.

522.731 Wheels and Tires

  • (a) Each landing gear main wheel must be approved.

  • (b) The maximum limit load rating of each wheel must equal or exceed the maximum radial limit load determined under the applicable ground load requirements. Each individual wheel of twin and tandem landing gears must be designed to support 70% of the maximum allowable weight.

Cockpit Design

522.771 General

  • (a) The cockpit and its equipment must allow each pilot to perform his duties without unreasonable concentration or fatigue.

  • (b) A means must be provided to enable ballast provided in accordance with 522.31(c) to be stowed safely in the glider.

522.773 Cockpit View

Each cockpit must be free from glare and reflections that could interfere with the pilot’s vision, and designed so that:

  • (a) the pilot’s vision is sufficiently extensive, clear and undistorted for safe operation; and

  • (b) each pilot is protected from the elements. Rain and icing may not unduly impair his view along the flight path in normal flight and during landing.

522.775 Windshields and Windows

  • (a) Windshields and windows must be constructed of a material that will not result in serious injuries due to splintering.

  • (b) Windshields and side windows of the canopy must have a luminous transmittance value of at least 70% and must not significantly alter the natural colours.

522.777 Cockpit Controls

  • (a) Each cockpit control must be located to provide convenient operation, and to prevent confusion and inadvertent operation.

  • (b) The controls must be located and arranged so that the pilot, when strapped in his seat, has full and unrestricted movement of each control without interference from either his clothing (including winter clothing) or from the cockpit structure. The pilot must be able to operate all the controls necessary for the safe operation of the glider from the seat designated to be used for solo flying.
    (amended 2000/11/25)

  • (c) In gliders with dual controls it must be possible to operate the following secondary controls from each of the two pilots’ seats:

    • (1) release mechanism;

    • (2) air brakes;

    • (3) wing-flaps;

    • (4) trim;

    • (5) opening and jettisoning device of the canopy;

    • (6) throttle lever.

  • (d) Controls must maintain any desired position without requiring constant attention by the pilot(s), and must not tend to creep under system loads or vibration. A means of adjusting the freedom of operation of the throttle control during flight to achieve this, must be provided. Controls must have adequate strength to withstand loads without failure or excessive deflection.

(Change 522-1 (87-08-31))
(Change 522-2 (93-06-30))

522.779 Motion and Effect of Cockpit Controls

Cockpit controls must be designed so that they operate as follows:

(Change 522-1 (87-08-31))
(Change 522-2 (93-06-30))

Controls Motion And Effect
Aileron Right (clockwise) for right wing down
Elevator Rearward for nose up
Rudder Right pedal forward for nose right
Trim Corresponding to sense of motion of the controls
Air brakes Pull to extend
Wing-flaps Pull for wing-flaps down or extended
Towing cable release Pull to release
Canopy jettisoning Not prescribed - preferably pull to jettison
Throttle control Forward to increase power
Propeller pitch Forward to increase (r.p.m.)
Mixture Forward, or up for rich
Carburettor air heat or alternate air
(amended 2000/11/25)
Forward or upward for cold, or
alternate air off
(amended 2000/11/25)

522.780 Colour Marking and Arrangement of Cockpit Controls

Cockpit controls must be marked and located as follows:

Control Colour Location
Towing cable release yellow for left hand operation
Air brakes blue for left hand operation, or in the case of a two-seat glider
Trimmer (longitudinal trim only) green preferably for left hand operation
Canopy operating handle white* not prescribed
Canopy jettison handle red* not prescribed but must be within easy reach
Other controls to be clearly marked but not yellow, blue, green, white or red  
* If canopy opening and jettison are combined in one handle, the colour must be red.

522.781 Cockpit Control Knob Shape

The towing cable release control must be so designed to be capable of operation by a gloved hand exerting the force specified in 522.143(c).

(Change 522-2 (93-06-30))

522.785 Seats and Safety Harnesses

  • (a) Each seat and its supporting structure must be designed for an occupant weight in accordance with 522.25(a)(2) and for the maximum load factors corresponding to the specified flight and ground conditions including the emergency landing conditions prescribed in 522.561. Each seat and its supporting structure must also be designed to withstand the reaction to the load specified in 522.397(b).

  • (b) Seats including cushions must not deform to such an extent that the pilot when subjected to loads corresponding to 522.581 and 522.583, is unable to reach the controls safely, or that the wrong controls are operated.

  • (c) Each seat in a glider must be designed so that an occupant is comfortably seated, whether he wears a parachute or not. The seat design must allow the accommodation of a parachute worn by an occupant.

  • (d) The strength of the safety harness must not be less than that following from the ultimate loads for the flight and ground load conditions and for the emergency landing conditions according to 522.561(b) taking into account the geometry of the harness and seat arrangement.

  • (e) Each safety harness installation must be designed so that each occupant is safely retained in his initial sitting or reclining position under any acceleration occurring in operation.
    (amended 2003/01/15)

  • (f) Each seat and safety harness installation must be designed to give each occupant every reasonable chance of escaping serious injury under the condition of 522.561(b)(1) and 522.561(b)(2).
    (amended 2010/05/27)

522.786 Protection from Injury

  • (a) Rigid structural members or rigidly mounted items of equipment, must be padded where necessary to protect the occupant(s) from injury during minor crash conditions.

  • (b) Structural members, which by the nature of their size or shape are capable of piercing the instrument panel, must be designed or positioned such that injury to occupants is unlikely, under the conditions of 522.561(b)(2).

(Change 522-1 (87-08-31))

522.787 Baggage Compartment

  • (a) Each baggage compartment must be designed for its placarded maximum weight of contents and for the critical load distributions at the appropriate maximum load factors corresponding to the flight and ground load conditions of this Chapter.

  • (b) Means must be provided to protect occupants from injuries by movement of the contents of baggage compartments under an ultimate forward acceleration of 15.0 g.
    (amended 2010/05/27; previous version)

522.788 Headrests
(amended 2003/01/15)

  • (a) A headrest must be provided to protect each occupant from rebound injuries in the event of a crash landing. It must be equipped with energy absorbent padding protected against wear and weathering encountered in normal operation. If an adjustable headrest is provided it must be capable of being positioned such that the point of head contact is at eye level.
    (amended 2003/01/15)

  • (b) Each headrest must be so designed to minimize the possibility of clothing or the parachute becoming caught when bailing out.
    (amended 2003/01/15)

  • (c) Each headrest in its most critical position must be designed for an ultimate load of at least 135 daN normal to a vertical plane which touches the contact point of the head.
    (amended 2003/01/15)

  • (d) The width and design of the headrest must not unduly restrict vision from either seat.
    (amended 2003/01/15)

522.807 Emergency Exit

  • (a) The cockpit must be so designed that unimpeded and rapid escape in emergency situations during flight and in any normal or crash attitude on the ground is possible with the occupant wearing a parachute.
    (amended 2012/03/27)

  • (b) The opening and where appropriate, jettisoning, of each canopy or emergency exit must not be prevented by the presence of the appropriate aerodynamic forces and/or the weight of the canopy at speeds up to VDF or by jamming of the canopy with other parts of the glider. The canopy or emergency exit attachment fittings must be designed to permit easy jettisoning, where jettisoning is a necessary feature of the design.

  • (c) The opening system must be designed for simple and easy operation. It must function rapidly and be designed so that it can be operated by each occupant strapped in his seat and also from outside the cockpit.

  • (d) A canopy or emergency exit jettison system must be actuated by not more than two controls, either or both of which must remain in the open position. The canopy jettisoning controls must be capable of being operated with a pilot effort of between 5 and 15 daN. If two controls are used they must both move in the same sense to jettison the canopy. If there are controls for each pilot, both controls or sets of controls must move in the same sense. If a single control is used for jettisoning, it must be designed to minimise the risk of inadvertent or unintentional operation towards the jettison position.

  • (e) In order to enable the occupants to bail out under acceleration conditions, sufficiently strong cabin parts, or grab-handles, must be available and suitably located so that the occupants can lift themselves out of their seats and support themselves. These parts must be designed to an ultimate load of at least 200 daN in the anticipated direction of force application.

(Change 522-2 (93-06-30))

522.831 Ventilation

  • (a) The cockpit must be designed so as to afford suitable ventilation under normal flying conditions.

  • (b) Carbon monoxide concentration must not exceed one part per 20,000 parts air.

(Change 522-1 (87-08-31))

522.857 Electrical Bonding

  • (a) Electrical continuity must be provided to prevent the existence of differences of potential between components of the powerplant including fuel and other tanks, and other significant parts of the powered glider which are electrically conductive.

  • (b) If the glider is equipped for winch or auto launching, electrical continuity must be provided between the metallic parts of the cable release mechanism and the control column.

  • (c) The cross-sectional area of bonding connectors, if made from copper, must be less than 1.33 mm2.

(Change 522-1 (87-08-31))

522.881 Ground Handling

There must be reliable carrying and lifting provisions for the glider.

522.883 Ground Clearance

  • (a) There must be at least 0.10 m of ground clearance for the tail-plane with the wing-tip touching the ground.

  • (b) With the wing-tip touching the ground, the associated aileron may not touch the ground when deflected fully down.

522.885 Fairings

Removable fairings must be positively attached to the structure.

522.891 Water Ballast Tanks: General
(amended 2007/07/16)

Each water ballast tank, its surrounding structure, hoses, valves and fittings, must be able to withstand, without failure, the vibration, inertia, fluid head (partial and full tank, wing deflections in flight and filling procedures) loads from filling procedures and structural loads that may be encountered in service.
(amended 2007/07/16)

522.892 Water Ballast Tanks: Tests
(amended 2007/07/16)

Unless loads from 522.891 are higher each water tank including hoses, valves and fittings, must be able to withstand a pressure of 0.20 bar without failure or leakage.
(amended 2007/07/16)

522.893 Water Ballast Tank Installation
(amended 2007/07/16)

  • (a) General. The surrounding aircraft structure must be appropriately protected from any likely damage (corrosion, debonding, etc.) from water ballast leaks.
    (amended 2007/07/16)

  • (b) Water ballast tanks which are not an integral part of the structure must be supported so that the loads resulting from the mass of the water ballast are not concentrated. In addition:
    (amended 2007/07/16)

    • (1) Means must be provided to prevent chafing between each tank and the supporting structure.
      (amended 2007/07/16)

    • (2) Each tank compartment must be vented and drained.
      (amended 2007/07/16)

  • (c) For integral tanks the surrounding structure must either be shown to be impervious to ballast absorption, or suitably protected.
    (amended 2007/07/16)

522.894 Water Ballast Tank Vents
(amended 2007/07/16)

Integral and other non flexible tanks must be vented.
(amended 2007/07/16)

522.895 Water Ballast System
(amended 2007/07/16)

  • (a) The water ballast control and jettison system must be designed so that any single malfunction will not produce a lateral or longitudinal movement of the centre of gravity that prevents continued safe flight and landing.
    (amended 2007/07/16)

  • (b) Water contamination of the pitot/static system, or water collection in any parts of the glider where it could cause corrosion or produce significant centre of gravity changes, must be prevented.
    (amended 2007/07/16)

522.896 Water Ballast Drains
(amended 2007/07/16)

There must be means to allow drainage of the entire water ballast system with the glider in the normal ground attitude.
(amended 2007/07/16)

522.897 Water Ballast Additives
(amended 2007/07/16)

If water ballast additives are permitted by the Flight Manual, they must be shown to have no adverse or damaging effects on structure or systems critical to flight safety.
(amended 2007/07/16)