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Electronic Flight Bag
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|Category:||Loss of Control|
The term "Electronic Flight Bag" covers any portable electronic display hardware intended primarily for flight deck or cabin use. ‘EFB devices’ can store and display a variety of aviation data or perform basic calculations for aircraft performance or fuel loading purposes.
In the past, many of these functions were traditionally accomplished using paper references carried on board the aircraft or were based on data provided to the flight crew in various ways by an Operator’s ‘flight dispatch’ organisation. The goal is for a fully configured EFB system to be able to facilitate a paperless flight deck.
The scope of the EFB system functionality may also include various other hosted databases and applications. EFB Hardware may use various technologies, formats, and forms of communication. Devices which function as an EFB may be referred to as an Auxiliary Performance Computer (APC) or as a Laptop Auxiliary Performance Computer (LAPC).
EFB Hardware should be seen as part of an EFB system, in which the effectiveness of the hardware function is assured by its place in that system. It is expected that overall responsibility for maintaining the integrity of EFB systems will be specifically assigned.
There is broad NAA agreement on the approach which will be taken in respect of EFB systems. The remainder of this summary is therefore generic and the detail may be found in the references given under ‘Further Reading’.
Classes of EFB System Hardware
Three classes of EFB System Hardware have been defined by reference to their progressively increasing sophistication starting with Class 1:
Class 1 EFB Systems do not require NAA airworthiness approval. They can be used both on the ground and during flight, but must be stowed for takeoff and landing. They are limited to providing supplemental information only and cannot replace any required system or equipment.
The hardware is:
- generally Commercial-Off-The-Shelf (COTS)-based computer systems adapted for aircraft operational use
- connected to aircraft power through a certified power source,
- not attached to an aircraft mounting device,
- considered for regulatory purposes to be a controlled PED (Portable Electronic Device),
- normally without aircraft data connectivity except under specific condition
Class 2 EFB Systems require a limited NAA airworthiness approval. Although considered to be a portable electronic device, an entry in the Aircraft Technical Log is required to remove a Class 2 EFB from the aircraft. It can be connected to aircraft power and to the aircraft’s data link port and can exchange data with aircraft systems, enabling it to make interactive performance calculations. It can be used to compute weight and balance information as well as takeoff and landing speeds, and to display flight critical pre-composed data, such as navigation charts. Since it is not necessarily stowed for takeoff and landing, pilots can use it to display departure, arrival, and approach charts.
The hardware is:
- generally COTS-based computer systems adapted for aircraft operational use
- connected as required to aircraft power through a certified power source
- connected when in use to an aircraft mounting device, such as an arm-mount, kneeboard, cradle or docking station, during normal operations
- aircraft power and data connectable
- capable of quick-disconnection for egress if necessary
- considered for regulatory purposes to be a ‘controlled PED’
- allowed to be connected to aircraft avionics
Class 3 EFB Systems are installed aircraft equipment requiring an STC or a certification design approval as well as NAA Airworthiness approval. Paper charts may not be required. Depending on the model, it may be connected to the GPS or FMS and it may be able to combine GPS position with the locations and speed vectors of other aircraft and graphic weather information into a single, detailed moving map display. Its detailed database can also provide obstacle and terrain warnings.
The NAA approval will take particular account of:
- the integrity of the EFB hardware installation including its data storage function, the display, the keyboard and the power switching process including hardware and software qualification.
- The issues arising from the human-machine interface
Airworthiness Issues Relating to EFB Hardware
Class 1 EFB requires an assessment of the physical use of the device on the flight deck and risks associated with Electromagnetic interference and the use of Lithium Batteries should be addressed. The EFB power source should be designed such that it may be deactivated at any time. Depending on the use to which the EFB is put, it may be appropriate to have an alternate power supply available. The EFB may not be connected to any aircraft system but may be connected to non aircraft systems on the ground only.
Class 2 EFB requires an airworthiness approval for the mounting arrangement, its crashworthiness when installed and in respect of its data connectivity and power connection. It is expected that an assessment of the physical use of the device on the flight deck and any risks associated with Electromagnetic Interference and the use of Lithium Batteries will be made. The EFB power source should be designed such that it may be deactivated at any time. Data connectivity should to validated and verified to ensure non-interference and isolation from aircraft systems should be validated.
Class 3 EFB requires a full airworthiness approval based upon compliance in relation to the intended function and safety of the interfaces with aircraft avionics data sources. A Class 3 EFB may form part of a network supporting other functions. A human factors assessment should be conducted.
EFB Applications Classification
Three classes of progressively increasing sophistication are defined starting with Type A. In summary, they are as follows:
- TYPE A APPLICATIONS - document storage and retrieval
- TYPE B APPLICATIONS - applications software which enables the independent performance of calculations needed for the operation of the aircraft, the display of aeronautical charts without actual aircraft position, use of electronic checklists, uses the Internet and/or other aircraft operational communications, displays weather information or facilitates aircraft video camera surveillance displays
- TYPE C APPLICATIONS - relate to the active control of the aircraft in flight and/or duplicate any certified avionics system and/or which, due to automatic interactions with other aircraft systems, displays and controls, raise significant human factors issues
EASA Proposed Amendment (NPA 2012-02)
During 2012 EASA proposed NPA 2012-02 ‘Airworthiness and operational criteria for the approval for Electronic Flight Bags (EFBs)’ which includes three major aspects:
- Improved definitions of EFB classes and types to make them more precise and objective, i.e. better delimiting the boundary between what has to be considered as part of the on-board avionics and the ‘non-avionics’ part of the flight crew compartment.
- The proposed data connectivity between EFBs and avionics is:
- not allowed for class I EFBs;
- allowed from the avionics to the EFBs for class II (i.e. ‘one way’);
- allowed in both directions for class III; redefinition of the roles and responsibilities of the competent authorities at national level and of the Agency, taking into account the provisions of the Basic Regulation and the related imminent Implementing Rules, in particular for air operations and for Operational Suitability Data (OSD).
- Redefinition of the roles and responsibilities of the competent authorities at national level and of the Agency, taking into account the provisions of the Basic Regulation and the related imminent Implementing Rules, in particular for air operations and for Operational Suitability Data (OSD).
The NPA outlines that the EASA is aware that the EFB issue can be controversial. Nevertheless, the EASA deems that: the improper use of EFBs may cause safety concerns; continuous progress of Information Technology on the commercial market outside aviation, leading to increasing use and requests for EFB applications, requires rulemaking initiative from the Agency in the earliest possible time. EASA reserves the right to take any position after the consultation. These positions will be published in the subsequent Comment-Response Document (CRD).
Accident & Incident Reports
The following accidents and incidents involved crews using an EFB.
- B742, Halifax Canada, 2004 (HF GND LOC FIRE): On 14 October 2004, a B742 crashed on take off from Halifax International Airport, Canada, and was destroyed by impact forces and a post-crash fire. The crew had calculated incorrect V speeds and thrust setting using an EFB.
- A345, Melbourne Australia, 2009 (RE HF): On 20 March 2009 an Airbus A340-500, operated by Emirates, commenced a take-off roll for a normal reduced-thrust take-off on runway 16 at Melbourne Airport. The attempt to get the aircraft airborne resulted in a tail strike and an overrun because insufficient thrust had been set based upon an incorrect flight crew data entry in the EFB performance calculation. The ATSB report into this incident includes some specific references to the use of EFBs:
- B733, Chambery France, 2012 (LOC HF): A B737-300 failure to become airborne from runway 36 at Chambery following rotation at the calculated speed and subsequent tail strike.
- EASA NPA No 2012-02 ‘Airworthiness and operational criteria for the approval for Electronic Flight Bags
- FAA Advisory Circular 120-76B; "Guidelines for the certification, airworthiness and operational approval of Electronic Flight Bag computing devices", 2003
- FAA Advisory Circular 91-78 2007; "Use of Class 1 or Class 2 Electronic Flight Bags", 2007
Transport Canada Transport Canada Advisory Circular 700-020: Electronic Flight Bags
- JAA SIC No.7 Information on findings and recommendations related to the use of an Electronic Flight Bag, 2006
- JAA Temporary Guidance Leaflet 36: "Approval of Electronic Flight Bags (EFBs)" 2004