OPERATIONS MANUAL PART A INSTRUCTIONS AND TRAINING REQUIREMENTS FOR THE AVOIDANCE OF CONTROLLED FLIGHT INTO TERRAIN AND POLICIES FOR THE USE OF GPWS

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1 PAGE: 1 Table of Contents A.GENERAL /CHAPTER POLICIES FOR THE USE OF GPWS GPWS and Upset Training Requirements GPWS General Alerts and Warnings Levels of GPWS and Actions Required on Receipt of Alert /Warning Basic GPWS Advanced GPWS Terrain Awareness and Warning System Unwanted Warnings... 5

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3 PAGE: 3 A. GENERAL / CHAPTER REQUIREMENTS FOR THE AVOIDANCE OF POLICIES FOR THE USE OF GPWS 31. Instructions and Training Requirements for the Avoidance of Controlled Flight into Terrain and Policies for the use of GPWS 31.1 GPWS and Upset Training Requirements All ACA Flight Crew Members are required to satisfactorily complete GPWS and Upset prevention and recovery training. GPWS training and Upset training is covered in the following ACA training courses: Initial Training; Conversion Training; Upgrade Training; Recurrent Training. Note: See OM, 4 Part D. Training for specific training modules and training times for GPWS and Upset training GPWS General The ground proximity warning system (GPWS) is to be turned on and used throughout the entire flight unless it has become unserviceable and the MEL for the particular aircraft type permits It to remain so for a specified period. The following paragraphs are intended as a guide to the purposes and use of GPWS generally; specific technical details of particular equipment will be Included in the approved AFM for the aircraft type. GPWS automatically provides aural warnings, which may be supplemented by visual signals, on one of the following: Sink rate, Ground proximity, Altitude loss after take-off or go-around, Incorrect landing configuration, and downward glideslope deviation. These warnings and alerts require immediate action by the Flight Crew. Flight Crews need to be aware of the following: An Immediate and positive response must be made to all GPWS alerts and warnings. GPWS response action may result in high pitch angles. Investigation of the reason for an alert/warning must take second place to the response action. The crew must react to a Ground Proximity Warning by the GPWS. In VMC, by day and visual with the ground, if the obstacle is clearly visible, modify the airplane flight path accordingly. In all other case: The illumination of the red PULL UP light must result in a go-around; All other alarms must be acknowledged and accomplish the appropriate flight changes Alerts and Warnings Alerts and warnings are defined as follows: (a) Alert - a caution generated by the GPWS equipment. (b) Warning - a command generated by the GPWS equipment which may be: (i) Genuine, i.e. in accordance with its technical specification; (ii) Nuisance, i.e. although the equipment is operating as intended, the pilot is following an authorized, safe procedure; (iii) False, i.e. the equipment is not operating as designed and the warning is spurious. Irrespective of their nature, all alerts and warnings are to be reported to ACA so that the circumstances may be investigated and the reliability of the equipment established. Flight crews must beware of becoming slow to react to GPWS alert/warnings purely on the basis of previous suspect performance.

4 PAGE: 4 GPWS is intended to provide warning of unintentional closure with the ground as a result of which remedial action can be taken. It is not infallible, but an immediate and positive response must be made to all its alerts and warnings. During GPWS response action high pitch angles may result. Investigation of the reason for the alert/warning must take second place. ACA policy on GPWS requires that: Except in clear daylight VMC when the Flight Crew can immediately and unequivocally confirm that an impact with the ground, water, or an obstacle will not take place: React immediately to a GPWS warning. Carry out the terrain avoidance maneuver for your aircraft type. Continue the escape maneuver until climbing to the minimum sector safe altitude or until visual verification can be made that the aircraft will clear the terrain or obstacle, even if the GPWS warning stops. Note: - Although some manufacturers of GPWS equipment may show in their literature Too Low Terrain to be an alert, the response to this must be as for a warning Levels of GPWS and Actions Required on Receipt of Alert / Warning Basic GPWS As indicated in the above Table, basic GPWS equipment gives warnings, rather than alerts, in all modes except Mode 5, Descent below Glideslope. In this mode, activation will cause the aural warning Glideslope to be repeated, and the Flight Crew must take immediate action to regain the glideslope as quickly as possible until the alert ceases Advanced GPWS The more advanced GPWS equipment indicates the mode of operation and provides alerts as well as warnings (see Table above). The immediate action on receiving an alert will vary according to the stage of flight and aircraft configuration but should involve correcting the condition for which the alert was valid. No attempt should be made to recover the original flight path until the cause of the alert has been positively established and eliminated. Whenever a warning is received, however, the immediate response must be to level the wings and initiate a maximum gradient climb to the (MSA) for the sector being flown, except as above. Warnings - Discretionary Action by Pilot-in-Command The response to a warning, as outlined above, may be limited to that appropriate to an alert only if: The aircraft is being operated by day in conditions which enable it to remain within a distance of 1 nm horizontally and 1000 feet vertically from cloud, and in-flight visibility of at least 5nm; and It is immediately obvious to the Pilot-in-Command that the aircraft is in no danger in respect of its configuration, proximity to terrain or current flight maneuver Terrain Awareness and Warning System Existing GPWS equipment does not have a forward-looking facility so that little or no warning may be given if the aircraft is approaching sharply rising terrain. Alerts and warnings in Modes 1 and 2 are only given when the aircraft is less than 2,500 feet above the local terrain. If no corrective action is taken, a maximum of some 20 seconds will elapse between initial receipt of the alert/warning and contact with the ground, and this will be lessened if the rate of descent is excessive, or there is rising ground beneath the aircraft. In addition to the basic or advanced GPWS equipment, the TAWS functions give forward-looking warnings to the Flight Crew. This information is not only based on Radio Alliance but also uses a database with terrain Information. Terrain Awareness and Warning Systems automatically provide visual and aural signals. This information is displayed on a Terrain Awareness Display. It gives the Flight Crew sufficient alerting time to prevent "Controlled Flight into Terrain"- events (CFIT). It also provides forward looking capability and a terrain clearance floor. Whenever a warning is received, and a response is required, the immediate response must be to level the wings and initiate a maximum gradient climb to the minimum safe altitude (MSA) for the sector being flown.

5 PAGE: 5 The PF performs the maneuver, but the Pilot-in-Command has/keeps the responsibility for the effectiveness and safety of this maneuver Unwanted Warnings Unwanted (i.e. false or nuisance) warnings may be received during normal, safe operations when, for example, the aircraft is being vectored by ATC and is descending in an area of hilly terrain particularly at high speed with a high closure rate and/or intense rising sandstorm. A Mode 5 (glideslope) alert may be triggered when the aircraft is being flown outside the validity area of the glideslope signal, such as when maneuvering visually to land on a non-instrument runway following an approach to the ILS runway. An alert/warning may also be triggered if the approach is flown with the flaps set to a different position from that normally used for landing. Provided that Flight Crews remain fully aware of these limitations of the equipment, however, and follow the recommended procedures immediately on receipt of GPWS alerts and warnings, its use may well avoid an otherwise inadvertent closure, or contact, with the ground. It is emphasized that even if a warning is anticipated or suspected to be false or nuisance, immediate and aggressive action is required by the crew unless it is beyond doubt.

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