Australian Transport Safety Bureau Assignment

The Risk of Flying at the Edge of Safety
Envelop

Table of Content
INTRODUCTION ..........................................................................................................................1
LITERATURE REVIEW................................................................................................................1
ANALYSIS OF AIRCRAFT ACCIDENTS (USA)........................................................................7
Australian Transport Safety Bureau.............................................................................................7
National Transportation Safety Board.......................................................................................10
Safety Trends for the Air Transport Industry with Dynamic Stall:...........................................11
Prediction Model........................................................................................................................13
Main Stages of flight..................................................................................................................13
Stall Envelop..............................................................................................................................16
CONCLUSION..............................................................................................................................19
REFERENCES..............................................................................................................................20

INTRODUCTION
The loss of control over the flights has been considered as the major issues which leads to have
the causing of the fatal aircraft accidents in the past history. There are many of the accident
which has been discussed by the various regarding the development of worldwide commercial
aircraft accidents. According to International Civil Aviation Organization the LOC and the stall
has been the high level of manifestation for the deviation of aircraft from the target path. In the
aircraft accidents most time inadvertent looses of control takes place which usually evolve
around the full stall or an approach to a stall in the sequence of event. Aerodynamic stall refers to
the condition in which aircraft used to have exceeded the critical angle of the attack ans no
longer in the situation to have the production of the required lift for the aviation of normal flight.
This is also termed as the undesirable condition inn which the wings experienced the increase air
resistance and decrease level of drift. This turns out to reason for air-plane crash. In this repost ,
the discussion regarding the various fatal aircraft accidents due to stall will be discussed. The
current trends regarding the prevention from stall along with prediction model will be
implemented. The repost will cover all the aspects regrading the well-development of
aerodynamics issues.
LITERATURE REVIEW
The imitation of the nature flapping wing flight has been the oldest aeronautical dreams
of humanity. According to Gregory & Bons, (2016) the inadvertent loss of control among aircraft
usually involves around a full stall or the approach at some certain stage in sequence of events
take place. The author also stated that the approached is identified as the as initiating factor or
later consequences. On the other hand the Hansen, (2015) contradict that is lack and avoidance
of awareness of aerodynamic wings in reference of particularly to multi engine public transport
aircraft. The subjects regarding the stall detection and recognition along with generic
requirement of stall recovery is also facing the lack of awareness and avoidance.
According to Lind & Jones, (2016) high incidence stall is the term used for the airflow
behaviours mostly refereed as high speed stall. The author also supported that the wing mounted
at an angel of incidence along with fuselage close to horizontal, there is the situation when wing
has small positive angle of attract relative to airflow. In contradiction, as the speed of air is
reduces, there will be increase in angle of attacks as to maintain the lift value produced by wins.
1

This process will take place in continuation till critical angle will be dependent upon cross
section of aerofoil, wing configuration along with design platform.
As per the views of Sørensen & Ferreira, (2016) stall have been the inherent hazard since
the era of beginning of flying. But with the loss of controlling from an aeroplane leading to cause
for worldwide commercial accidents of aircraft. The author also stated that there should be
enough training for stall recovery along with use if ground simulators along with improvement
of flight models.
As per the views of Gregory and Bons, (2016) at the time of flying below transonic speed with
any weight of aircraft, the (IAS) i.e. indicated airspeed on which wing will stall is constant at all
altitudes as the two of indicated airspeed and critical speed change relative as compare to density
of air. The author also stated that as the situation when there is increase in altitude and decrease
in air density the gap distance between IAS and TAS will be increased till TAS have a
significant proportion with sound sped. The speed of air over the upper surface mostly have
excess if sound speed and waves of shock. On the other hand the Hansen, (2015) contradicts that
there are stall warning system that are adjusted in Mach number in modern aircraft.
According to Lind and Jones, (2016) there are many accidents and incidents which shoes that
most full or near to full stall of transport aircraft has occurred. The reasons reviewed from the
various literature can be inappropriate responses to an uncommanded autopilot use to
disconnects at altitude. As the Sørensen & Ferreira, (2016) contradicts that there is negligence of
practising the manual flying at higher altitude which makes the less awareness over flights
control at high altitude as comparative to lower altitude practising. The most lack in awareness of
air speed in which indicated airspeed in unintentionally allowed to deviates from the necessary
target at low attitudes. The Truong, (2017) contradicts as low altitude have the presence of
frozen ice deposits which is termed as Airframe Icing. More reason can be the lack of aircraft
management and flying skills.
As per the views of Lind and Jones, (2016) as to prevent the full aerodynamic stall of aircraft, the
design foe identification an impending stall at the incipient stage as pilot can occur with
intervention. The stall warning system is resigned as the pilot overload with due emergency or as
realizable situation can be escapes with effectiveness of waning system along with fully. There
are generic indicators of the aerodynamic stall which includes all about the activation of artificial
stall warning along with aircraft buffet. On the other hand the Hansen, (2015) contradict as no
2

aircraft has the audio stall warning along with no buffet is experience by aircraft during stall. The
Sørensen & Ferreira, (2016) also stated that there should be in flight control authority but the
there is contradiction there in some Fly By Wire such as Air-bus A320, there is no presence of
flight deck control displacement. There are more of the topics that has been discussed by various
authors regarding the nose down pitching tendency at the point the stall occurs along with high
rate of descent. On the other hand the contradiction is that in some swept wings the aircraft
experience a nose pitching tendency.
All these points above disclosure are at the critical viewpoints as there is thorough understanding
of the characteristics regarding stall and their aircraft. The pilots also extent there knowledge
with continuation in knowledge for aircraft stall warning, their prevention and recovery system
inclusive with limitation.
As the view point Gregory & Bons, (2016) there should be better understanding within the pilot
in able to recognize the stall characteristics for air craft type. This will help in having the proper
implementation of recommend recovery technique. The Truong, (2017) have further discussed
the auto pilot and auto throttle disconnection. The author state that ensuring the maintenance of
attitude of aeroplane, the disconnection occur between auto pilot and auto throttle. The pilot
should have the assurance that the pitch attitude doesn't increase. There is essential requirement
of manual controlling to have recovery over the situation. There can be inadvertent changes and
adjustment when the auto pilot is connected spastically at the high work load conditions. There
should be indemnification of the nose pitch control by the pilot till the time there is elimination
of stall warning or have the trim of pitch nose down. The pilot should have the reduction in angle
of attack for the recovery at crucial level. This will also we addressed to auto pilot to have the
excessive nose up trim. However, the SKOUSEN, (2018) contradict that the excessive use of
nose up trim, the conditions can be more critical and may end up in resulting loss of control or
having the high structural control.
According to Lind & Jones, (2016) there is need for thrust for recovery of stall. There can
be occurrence of stall at high thrust or at idle one. So the thrust should be recovered according to
need. In the case where airspeed is low, the aeroplanes with install engines will apply maximum
thrust which may have creation of strong nose pitching statement. On the other hand the Aji,
(2015) contradict as the engines which are mounted above the wings in aircraft have the helpful
pitch down tendency due to thrust application. It used to increase the airflow and help in stall
3

recovery. The Truong, (2017) stated that there should be implementation of speed beaker or
retract as it is helpful in improving the lift abs stall margin. There is the implementation of gentle
action for recovery as preventing from secondary stall it to return for the desired path and have
the assurance and clearance from terrain.
According to Sørensen & Ferreira, (2016) the best way foe avoiding the inadvertent stall is to be
aware of conditions in which there is maximum chancer of stall likely yo happen. As to avoid
such situation, technical mitigation should be there along with stall warning system devices and
flight envelop protection system so that it can be more effective in such unfavourable conditions.
There should be proper flight training along with classroom ans full flight simulator as to reduce
the heightened risk of stall with in application and adherence of appropriate SOPs. On the other
hand the SKOUSEN, (2018) contradicts as the flight training along with classroom and full flight
simulator as to reduce the heightened risk of stall with in application and adherence of
appropriate SOPs will be largely depends on the individual competency of pilot. However, the
Truong, (2017) argued that the widespread adoption provides an opportunity to analyse the range
of less ‘precursor’ events where the abnormal deviation from an expected flight path towards
stalled condition followed successful recovery. Such occurrences can be tracked back for a
particular pilots and to training histories, enabling gaps in pilot training, knowledge or SOPs to
be addressed throughout an operator’s fleet.
As per the view of Deng, Wang & Liang, (2017) stalling is a condition where the aircraft
loss its speed of lift and find difficulty to glide in air. There are different reasons of these which
can lead the air plane to this situation. There are major three factors which can cause stalling
which are weight load factor, attack angle and speed of air craft. These are the most common
reason of stalling. As per the observation and study of aircraft accidents it can be evaluated that
most frequent issue in stalling and crash is high attack angle of plane and low speed. This could
be human error or technical problem. Before the aircraft tack off a proper analysis is performed
to check the condition of aircraft but sometimes they are not able to calculate and find technical
issue in the engines and structure and later this cause stalling. This is considered as the human
error but in some situations weather condition cause technical failure in engines and fuel supply.
In extreme cases aircraft suffer from zero power that lead to stalling.
According to technical failures are more difficult to handle because this is not possible to
fix the aircraft in middle of flight. Some problems can be solved by troubleshooting process
4