Managing Flying Risk – In flight equipment including radio

Content

• Pilot safety and comfort
• Instruments
• Radio
• Lithium batteries

Pilot safety and comfort

Please note that glider cockpits are designed for a range of pilot sizes and pilot weights. Whether tall or small, large or slender, it is important for every pilot in command to ensure they and any passenger or student pilot are correctly seated and secured.

Seat backs

Some gliders, for example the K21, have removeable seat backs which need to be fitted correctly. Others, for example the Puchacz, have an integral adjustable seat back that needs to be correctly secured after adjustment.

When not in use, removeable seat backs should be stowed safely and securely where they can be protected from damage and accessed by those who need them to fly.

Cushions

All cushions should be energy absorbent – conventional soft foam actually stores energy and can be dangerous in an accident. It is recommended that all pilots fly using an energy absorbent cushion (the foam is stocked by several suppliers). The cushions should have attachments compatible with the glider for which they are provided and be secured so that they cannot move or foul any controls during any phase of flight.

When not in use, cushions used to support smaller pilots should be stowed safely and securely where they can be protected from damage and accessed by those who need them to fly.

A safety briefing describing why pilots should fly with an energy-absorbing foam cushion is available here.

Ballast weights

Ballast weights should be physically fixed to the glider. They should have attachments compatible with the glider for which they are provided and be secured so that they cannot move or foul any controls during any phase of flight.

When not in use, ballast weights should be stowed safely and securely where they can be protected from damage and accessed by those who need them to fly.

Parachutes

Most glider pilots fly with an emergency parachute. As gliders tend to fly close to other gliders, that’s a reasonable precaution. Parachutes have saved glider pilot’s lives.

The regulatory position is clear; emergency parachutes are not subject to regulation. Emergency parachutes are neither installed on aircraft as a component nor are they required by the UK ANO or the retained EU Sailplane Air Operations rules. Emergency parachutes are not subject of Part-ML maintenance rules. There is a BGA Operational Regulation that requires glider occupants to carry emergency parachutes when flying in cloud.

Prior to flight, the pilot and second seat occupant should ensure that they know how to fit the parachute harness correctly and how to operate the parachute. Detailed guidance on how to control and land with a parachute can be obtained from any British Skydiving school. Parachute harnesses for those small in stature are commercially available.

It is recommended that an owner of an emergency parachute, ie the person responsible for keeping the emergency parachute in a proper condition, maintains the parachute in accordance with the approved instructions published by the manufacturer. Common sense suggests that parachutes should be kept dry and clean at all times and that advice should be sought from an expert if a parachute becomes wet or contaminated.

Oxygen

Atmospheric pressure reduces with altitude; halving every 18,000 ft. Healthy humans can compensate for some lack of oxygen but only down to 150 hPa partial pressure of oxygen which is reached at 10,000 ft.  Symptoms of hypoxia are similar to those of alcohol and may include a dangerous overconfidence.  Performance is degraded; consciousness may be lost above 15,000 ft; and without warning above 25,000 ft. Because of how oxygen is transferred in the body, attempts to over-breathe both precipitate the problem and give optimistic readings with oximeters. At altitude the necessary water vapour and exhaled carbon dioxide take an increasing share of the pressure available.  The partial pressure of oxygen can be maintained by adding supplementary oxygen, but increasing amounts are required with altitude and even with pure oxygen the ground level equivalent is reached by 30,000 ft and the limit of compensation at 40,000 ft. The elderly and those with lung damage will suffer adverse effects at much lower levels. Any ill effects at altitude should be assumed to be hypoxia and require an emergency descent to below 10,000 ft.

The Sailplane Air Operations rule (SAO.OP.150) requires that the pilot in command shall ensure all persons on board use supplemental oxygen whenever he or she determines at the altitude of the intended flight, lack of oxygen may result in impairment. The related AMC notes that if the pilot in command cannot determine how the lack of oxygen will affect those on board, he or she should ensure all occupants use supplemental oxygen above 10,000 ft.

Oxygen equipment should be secured so that it cannot move or foul any controls or injure the pilot, even under extreme attitudes or accelerations.

When not in use, oxygen equipment should be stored where it can be protected from damage.

Personal Locator Beacon

Personal locator beacons (PLB) are relatively low cost distress radio beacons that help to detect the location of the PLB while in distress. Personal locator beacons now feature GPS using the dedicated 406MHz frequency. Operated by the pilot in an emergency, a PLB transmits the precise GPS location to the global network of search and rescue satellites. Owners of PLBs are reminded of the need to register and maintain the PLB.

Instruments

Audio Variometers

To assist pilots in maintaining effective lookout, gliders operating from BGA sites should be equipped with audio variometers and the pilots trained in their use.

GPS Moving Maps

Infringements of controlled airspace are potentially dangerous and disruptive, and ultimately result in curtailment of the freedoms to fly that all pilots need and enjoy. Use of GPS moving maps is encouraged, particularly where flying cross country in areas of complex airspace. Pilots should ensure they use up to date map software and learn how to use the device on the ground.

The installation of installed or carry on equipment such as a GPS moving map should ensure that the pilot’s lookout and emergency egress is not impaired.

Electronic conspicuity and collision warning systems

The BGA encourages the widespread use of electronic conspicuity and collision-warning systems in gliders, motor gliders and tugs. FLARM is an increasingly popular system. Pilots should make their own decision on equipage based on compatibility with other systems and as to whether such a system is appropriate for their particular operation. Pilots are reminded that whilst electronic collision warning equipment can enhance pilots awareness by providing most useful warnings, such equipment cannot and must not replace a good systematic visual lookout scan, and that it is necessary to avoid any in-cockpit equipment from distracting from the visual lookout scan.

Undercarriage Warnings

Fitting of undercarriage warning systems needs very careful consideration as an in-flight warning during the final stage of landing may lead the pilot to lower the undercarriage resulting in an accident due to loss of control. For the same reason, if a glider is seen wheel-up on the approach, no attempt should be made to warn that pilot.

Radio

The radio can be a very helpful situational awareness tool if used correctly. Planning ahead in terms of frequency selection and the message, using the correct call signs, and using clear, normal language all help to reduce the potential stress and distraction that can be associated with airborne use of radio.

Flight Radio Telephony Operator Licence (FRTOL)

An FRTOL is not required where a glider pilot is not communicating with any air traffic control unit, flight information unit or air/ground communications service unit, or is being trained in an aircraft registered in the United Kingdom to perform duties as a member of the flight crew of an aircraft (reference ANO Article 139).

Pilots who fly cross-country are encouraged to train for and obtain an FRTOL.

Emergency Frequency

The UK Distress and Diversion cell monitors channel 121.500. A position fixing service is available to any pilot who is lost or unsure of their position. Pilots are strongly advised to make themselves aware of how to get help from D&D. An FRTOL is not required to use this frequency.

SafetyCom

The SafetyCom channel, 135.480, is available to assist pilots to avoid potential collisions between arriving and departing aircraft where no airfield frequency is in use. Pilots may use this frequency to broadcast their intentions for safety purposes only.

Callsigns

Gliders should use “Glider” plus registration letters (where a glider is registered with the UK CAA); or “Glider” plus competition alpha-numeric or tri-graph

Vehicles should use either the suffix “mobile”, or “retrieve”

Portables should use the suffix “mobile”, “winch”, “launch” or “launch point”

Fixed should either use the suffix “base” or “glider base”

Situational awareness calls (eg “joining” or “downwind”) to other gliders in the air should be made with the suffix “traffic” (eg “Anytown Traffic, Glider AB downwind runway 23”)

Gliding Channels

The following table outlines the Primary and Secondary uses of the various channel assignments as determined by the BGA and agreed with the CAA and Ofcom. The alternative “Secondary Use” frequencies should only be used when the “Primary Use” channels are very busy.

Lithium batteries

Lithium-ion and lithium polymer batteries are the predominant type of rechargeable battery used to power the devices and vehicles that we use as part of our daily lives. They are used in sailplanes.

The batteries vary in size and configuration depending on their use and application. Batteries are arranged in series to increase voltage, and in parallel to increase capacity.

Fortunately, fire related incidents with these batteries are infrequent, but the hazards associated with lithium battery cells, which combine flammable electrolytes and significant stored energy, can lead to a fire or explosion from a single-point failure. These hazards need to be understood in order to suitably manage lithium-ion battery risks.

Lithium-ion batteries use liquid electrolytes; lithium-polymer batteries use solid or gel-like polymer electrolytes. Lithium-polymer batteries have an edge in safety due to their solid or gel-like electrolytes.

What do they look like?

There are several styles of Lithium rechargeable batteries: cylindrical, button, prismatic, and pouch cells. The cylindrical and button formats are inherently more robust than flat-format prismatic and pouch cells due to the structural properties of their shaped metal casings. Lithium glider batteries are similar only in size and shape to gelcel batteries but are significantly lighter.

What are the hazards?

If a battery cell creates more heat than it can effectively dissipate, it can lead to a rapid uncontrolled release of heat energy, known as ‘thermal runaway’, that can result in a fire or explosion.

This typically develops through the following events:

1. Temperature increase

2. Venting/gassing off of flammable/toxic electrolyte vapours

3. Flare

4. Steady burn

5. Flash fireball

6. Explosion

Ways that thermal runaway can start in batteries are;

• Damage to the battery

• Manufacturing defects

• Overcharging

• Over-discharging

• Short circuiting

• Water ingress

• Incorrect use of charger

• Poor quality battery – cell faults

• Poor condition of battery – cell faults

• Age of battery

Using Lithium batteries safely

• Only use batteries purchased from a reputable manufacturer or supplier.

• Do not leave/store batteries in contact with conductive materials.

• Always inspect batteries for any signs of damage before use and never use damaged or defective batteries.

• Only charge batteries with a suitable OEM (original equipment manufacturer) or compatible charger designed to safely charge the specific battery cells or battery packs in use.

• Do not leave batteries charging in unoccupied locations and disconnect/remove batteries from chargers after charging is complete.

• Handle batteries in well-ventilated areas and only use and store batteries in dry and reasonably cool locations, i.e. avoiding excessive humidity and heat. Avoid placing batteries in direct sunlight.

• Keep battery handling areas free from flammable or combustible materials, and free from sharp objects that may puncture battery cells.

• When not in use, lithium-ion batteries should ideally be kept in a bespoke enclosure such as a proprietary metal battery storage cabinet or fireproof safety bag

Additional Information

If a lithium battery cell explodes it can quickly spread to another battery, another device, or another flammable object. Fire extinguishers do not work on lithium-ion batteries fires. Water may not prevent a battery from burning and spreading. If you observe a lithium-ion battery fire, call the emergency services.

British Safety Council guidance

HSE – using batteries

IATA guidance

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