.  
ICAO – Human Factors Training Manual (Doc 9683).

.  
ICAO – Human Factors Digest No 8 – Human Factors in Air Traffic Control (Circular 241).

.  
FAR 121.406, 121.419, 121.421 or 121.422 -CRM Training.

.  
FAR 121.542 – Sterile cockpit rule.

.  
JAR-OPS 1.945, 1.955 or 1.965 - CRM Training.

.  
JAR-OPS 1.085(d)(8) – Sterile cockpit.

Intra-Cockpit Communications – Managing Interruptions and Distractions in Cockpit
Page 6

AIRBUS INDUSTRIE Getting to Grips with
 Flight Operations Support                         Approach-and-Landing Accidents Reduction

Introduction
Operators with international routes are exposed to different standards in terms of:
.  
Altitude measurement (i.e., feet or meters);

.  
Altitude reference setting-units (i.e., hectopascal or inch-of-mercury, QNH or QFE); and,

.  
Environmental conditions (i.e., atmospheric pressure changes and/or low OAT operation).

This Briefing Note provides a review and discussion of the following aspects, highlighting the lessons learned from approach-and-landing incidents and accidents:

.  
Barometric-altimeter reference ( QNH or QFE );

.  
Use of different units for altitude measurement (i.e., feet versus meters) and altimeter setting (i.e., In.Hg versus hPa);

.  
Setting of baro-altimeter bug and radio-altimeter DH;

.  
Radio-altimeter callouts; and,

.  
Low-OAT operation.

Statistical Data
Deviation from the intended vertical flight profile (caused by omission of an action or by an incorrect action) is frequently observed during line checks and audits.
The lack of situational awareness, particularly the lack of vertical situational awareness, is a causal factor in 50 % of approach-and-landing accidents (this includes most accidents involving CFIT).
QNH or QFE ?
The use of QNH for operations below the transition level / altitude eliminates the need for changing the altimeter-setting:
.  
During the approach and landing; and,

.  
During the missed approach, as required.

When QFE is used for the approach, the altimeter must be change to QNH for the missed-approach, unless the missed-approach procedure is defined with reference to QFE.
Some operators set the altimeter to QFE in areas of operation where the ATC and the majority of other operators use QNH. This requires adequate SOPs for altimeter-setting and for conversion of assigned altitudes to heights.
Altimeter-setting Units
Operators with international routes are exposed to the use of different altimeter setting units:
.  
Hectopascals ( hPa ), previously referred to as milibars ( mb ),

.  
Inches-of-mercury (in. Hg).

When in.Hg is used for altimeter setting, unusual barometric pressures such as:

.  
28.XX in.Hg (i.e., an unusually low pressure); or,

.  
30.XX in.Hg (i.e., an unusually high pressure),

may go undetected when listening to the ATIS or ATC, resulting in a more usual 29.XX altimeter setting being set.

Altimeter Setting – Use of Radio Altimeter
Page 1

A 1.00 in.Hg discrepancy in the altimeter setting results in a 1000-ft error in the intended (actual) altitude, as illustrated by Figure 1 ( Figure 1, Figure 2 and Figure 3 assume a 2000 ft airfield elevation and a 4000 ft indicated altitude).
In Figure 1, the actual QNH is an usually low 28.XX in.Hg but the altimeter setting was mistakenly set to a more usual 29.XX in.Hg, resulting in the actual altitude / height being 1000 ft lower than indicated:
　
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