THE HANDLING OF THRUST LEVERS DURING LANDING WITH A DEACTIVATED THRUST REVERSER

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SAFETY REGULATION GROUP
FLIGHT OPERATIONS
DIVISION COMMUNICATION
32/2007
Applicability: All Operators of Airbus A318/319/320/321
THE HANDLING OF THRUST LEVERS DURING LANDING WITH A DEACTIVATED THRUST REVERSER
FOR AIRBUS A318/319/320/321 AEROPLANES
1 Introduction
1.1 The CAA has been advised by the Joint Aviation Authorities (JAA) of an operational procedure which is
thought to incur an unacceptable risk, namely the handling of thrust levers during landing with a thrust
reverser deactivated. This FODCOM is issued to advise operators of the manufacturer’s recommended
operational procedure to select idle thrust on both engines during a landing conducted with one
deactivated thrust reverser. The term ‘A320’ is used in the following paragraphs to refer to A318, A319,
A320 and A321 aeroplanes.
2 Background
2.1 There have been at least three similar accidents/incidents that have occurred because the flight crew
failed to retard both thrust levers to the IDLE detent for the flare and landing when the A320 aircraft
were dispatched with one thrust reverser deactivated as allowed by the Minimum Equipment List
(MEL). The thrust lever corresponding to the engine with the deactivated thrust reverser was left in the
CLIMB detent during the flare and touchdown. MAX REVERSE thrust lever position was selected on
the engine with the operative thrust reverser. In each instance, the auto thrust system remained
engaged in the speed mode until selection of reverse on one engine disconnected the auto thrust
system, and the thrust system reverted to the manual mode. This resulted in the thrust increasing within
the range of the CLIMB limit thrust setting in order to maintain the selected speed. When the auto thrust
disconnected, the thrust remained at the last commanded thrust level per the lockout feature. Ground
spoilers did not deploy and autobrakes, if selected, did not activate. The most recent accident resulted
in 199 fatalities.
2.2 The A320 auto thrust system utilizes six detents: TOGA, FLEX/MCT, CLIMB, IDLE, REV IDLE, and
MAX REVERSE, to establish the maximum full authority digital engine control (FADEC) computed
thrust for the ambient conditions. The thrust levers do not move automatically but are manually placed
in one of the detents by the pilot. The A320 design requires that both thrust levers be retarded to the
IDLE detent by the pilot on landing to disconnect the auto thrust system, to initiate the system logic for
the deployment of ground spoilers and the activation of autobrakes, and to avoid an undesired increase
in thrust during the landing roll. In the case of dispatch with one thrust reverser deactivated, the Master
Minimum Equipment List (MMEL) and the recent Airbus Accident Information Telex (TAM JJ3054
AIT 4, August 2, 2007) each call for the pilot to set both thrust levers to idle for the flare and after
touchdown during thrust reversers application, select BOTH thrust levers. In all cases, the systemdesigned
logic requires that both thrust levers be retarded to the IDLE detent for flare and landing.
Pilots should follow operator specific procedures for the selection of reverse thrust.
2.3 The MMEL operational procedure was amended in 2006 to require both levers to be set to maximum
reverse at touchdown when operating with one thrust reverser deactivated. The intent of the revised
procedure is to mandate a symmetrical selection of the thrust reverser levers when one reverser out of
two is inoperative. The procedure requires MAX REV selection in accordance with the Airbus Standard
Operating Procedure (SOP) (see FCOM 3.03.22P5). An Airbus review of the published MMEL
operational procedure 02-78-30-01 is planned by the next revision to take into account long runway, no
contamination configurations. The planned wording that is to be introduced will be as follows: "During
thrust reversers application, select BOTH thrust levers". (This new wording is already contained in
A330/A340 MMEL.) The revised procedure was introduced to standardise and harmonise with the
normal operating techniques when both reversers are serviceable, thereby minimising normal and
MMEL dispatch procedural differences. Operators may wish to incorporate the guidance resulting from
the Airbus review in advance of the MMEL amendment, since the requirement to set MAX reverse in all
FLIGHT OPERATIONS DIVISION COMMUNICATION - 32/2007
2
circumstances adds no safety value in less limiting circumstances. The level of symmetrical reverse
selection may be decided according to prevailing conditions.
2.4 The standardised procedure contained in the MMEL requires an additional 55 metres to be added to
the scheduled landing distance required, which is caused by the slightly increased N1 of the engine
with deactivated thrust reverse. In practice, this increase in landing distance may not be observed since
it may be more than cancelled out by the reverse thrust selected on the engine with the serviceable
reverser, but this effect cannot be acknowledged in the calculation of landing distance required as
credit for the use of reverse thrust during landing is not permitted. The MMEL operational procedures
also contain the instruction that reverse thrust must not be selected when both thrust reversers are
inoperative.
3 Applicability
3.1 The information contained above is applicable to those aircraft dispatched in accordance with the
MMEL for Airbus A318/319/320/321 item 78-30.
4 Recommendation
4.1 Operators should take note of, and ensure that all affected personnel are familiar with, the
content of this FODCOM and of the relevant section of the MMEL. Operations manuals should
be amended to reflect current Airbus procedures in this respect.
5 Queries
5.1 Any queries as a result of this FODCOM should be addressed to Head of Flight Operations Policy
Department at the following e-mail address: FOP.Admin@caa.co.uk.
15 November 2007
Recipients of new FODCOMs are asked to ensure that these are copied to their 'in house' or contracted
maintenance organisation, to relevant outside contractors, and to all members of their staff who could
have an interest in the information or who need to take appropriate action in response to this
Communication.
Review FOI(A) February 2010