Question 265-1 : Which three aerodynamic means decrease manoeuvring stick forces ? [ Theoretical lift off ]

Question 265-2 : Which statement is correct i stick force per g is independent of altitudeii stick force per g increases when the centre of gravity moves forward ?

I is incorrect ii is correct.

Stick force per g is dependent of altitude rho changes with altitude pressure on the control surface will change if the cg moves forward static longitudinal stability increases and controllability decreases stick force increases a very high stick forces are required to pitch because the aircraft is very stable the magnitude of the stick force required to pitch for an aircraft with manual controls is determined by the distance the cg is forward of the neutral point

Question 265-3 : Which statement is correct ?

The short period oscillation should always be heavily damped.

com encom080 483ajpg com encom080 483jpgvdo925the short period oscillation should always be heavily damped short period oscillation is dangerous because structural failure usually results if the oscillation is not damped immediately short period oscillations affect airplane and control surfaces alike and reveal themselves as porpoising in the airplane or as in buzz or flutter in the control surfaces

Question 265-4 : Which statement is correct ?

During a phugoid altitude varies significantly but during a short period oscillation it remains approximately constant.

Img com encom080 483ajpg com encom080 483jpgvdo927

Question 265-5 : During a phugoid the speed ?

Varies significantly whereas during a short period oscillation it does not.

com encom080 483ajpg com encom080 483jpg

Question 265-6 : An aeroplane exhibits static longitudinal stability if when the angle of attack changes ?

The change in total aeroplane lift acts aft of the centre of gravity.

Question 265-7 : A negative contribution to the static longitudinal stability of conventional jet transport aeroplanes is provided by ?

The fuselage.

686generally the contributions of the wing fuselage and nacelles is de stabilizing together these components generate nonrestoring pitching moments when changes in lift coefficient occur if the airplane is to possess static longitudinal stability the horizontal tail must be designed to overcome the destabilizing influence of the remainder of the airplane's components the contribution of the horizontal tail to static longitudinal stability is powerful and almost always strongly stabilizing

Question 265-8 : A jet transport aeroplane exhibits pitch up when thrust is suddenly increased from an equilibrium condition because the thrust line is below the ?

Cg.

com encom080 526jpgthrust line is below the center of gravity if thrust is suddenly increased it creates a pitching moment

Question 265-9 : The aeroplane motion schematically illustrated in the annex is an example of a dynamically err a 081 529 ?

Unstable periodic motion.

Question 265-10 : The aerodynamic contribution to the static longitudinal stability of the nacelles of aft fuselage mounted engines is ?

Positive.

static stability refers to the initial tendency or direction of movement back to equilibrium in aviation it refers to the aircraft's initial response when disturbed from a given aoa slip or bankpositive static stability is the initial tendency of the aircraft to return to the original state of equilibrium after being disturbed longitudinal lateral and directional stability com encom080 547ajpghere we are talking about aft fuselage mounted nacelles com encom080 547bjpgand they are not a symmetrical body they are curved like aerofoils airflow around them produce aerodynamic forces it generates a nose up moment the plan area of the engines stub mountings and so on acts like an extra horizontal tail that aerodynamic force is stabilising it is the same as having a larger tailplane which gives positive longtitudinal stability

Question 265-11 : Stick force per g ?

Is dependent on cg location.

The magnitude of the stick force required to pitch for an aircraft with manual controls is determined by the distance the cg is forward of the neutral pointwhen the centre of gravity moves forward the stick force per g increases

Question 265-12 : Static lateral stability should not be too large because ?

Too much aileron deflection would be required in a crosswind landing.

High lateral stability results in high stick forces with the aircraft attempting to maintain a wing level attitude during a crosswind landing the aircraft will tend to yaw and sideslipthe sideslip component will result in lateral stability attempting to level the wing you therefore have to hold this roll off by applying aileron which if the stability is too high will require a larger aileron deflection

Question 265-13 : Positive static stability of an aeroplane means that following a disturbance from the equilibrium condition ?

The initial tendency is to return towards its equilibrium condition.

Question 265-14 : Positive static longitudinal stability means that a ?

Nose down moment occurs after encountering an up gust.

Question 265-15 : Static lateral stability should not be too small because ?

The aeroplane would show too strong a tendency to spiral dive.

Question 265-16 : The effect on static lateral stability of an aeroplane with a high wing as compared with a low wing is ?

A positive dihedral effect.

An aircraft that tends to return to wings level flight after it has been disturbed is considered to be laterally stable mounting the wings above the centre of gravity aids lateral stability because the weight of the aircraft will act as a pendulum to restore level flight'positive dihedral effect' when a wing goes down dihedral effect will tend to decrease bank angle and roll the wing back up this is a positive contribution to the static lateral stability

Question 265-17 : The effect of the wing downwash on the static longitudinal stability of an aeroplane is ?

Question 265-18 : The effect of a wing with sweepback on static directional stability is as follows ?

Stabilizing effect.

Wing sweepback aids in directional stability if the aircraft is rotated about the vertical axis the aircraft will be forced sideways into the relative windbecause of sweepback this causes the leading wing to present more frontal area to the relative wind than the trailing wing this increased frontal area creates more drag which tends to force the aircraft to return to its original direction of flight com encom080 558jpg

Question 265-19 : If the nose of an aeroplane yaws left this causes ?

A roll to the left.

If the nose yaw left a part of the left wing will be shadowed by the fuselage you will have more lift on the right wing inducing a roll to the left com encom080 567jpgthis phenomenon is increasing to an airplane with dihedral the right wing has a slightly increased angle of attack and therefore higher lift which causes more roll to the left

Question 265-20 : If the elevator trim tab is deflected up the cockpit trim indicator shows ?

Question 265-21 : If an aeroplane exhibits insufficient stick force per g this problem can be resolved by installing ?

Question 265-22 : How can the designer of an aeroplane with straight wings increase the static lateral stability ?

By increasing the aspect ratio of the vertical stabiliser whilst maintaining a constant area.

By making the tail fin taller while keeping the same area you are moving the cp of the fin further away from the aircraft cg giving more moment arm and thus more correcting roll force

Question 265-23 : If the total sum of moments about one of its axes is not zero an aeroplane would ?

Experience an angular acceleration about that axis.

Question 265-24 : The manoeuvre stability of a large jet transport aeroplane is 280 ng what stick force is required if the aeroplane is pulled to the limit manoeuvring load factor from a trimmed horizontal straight and steady flight cruise configuration ?

Question 265-25 : Which of the following provides a positive contribution to static directional stability ?

A dorsal fin.

Question 265-26 : The primary purpose of dihedral is to ?

Increase static lateral stability.

When a wing goes down dihedral effect will tend to decrease bank angle and roll the wing back up this is a positive contribution to the static lateral stability the dihedral effect is an increase in angle of attack on the lower wing compared to the upper wing

Question 265-27 : A conventional stabiliser on a stable aeroplane in a normal cruise condition 1 always provides negative lift2 contributes to the total lift of the aeroplane3 may stall before the wing in icing conditions with large flap settings unless adequate design andor operational precautions are taken4 is ?

Question 265-28 : During a take off roll with a strong crosswind from the right a four engine jet aeroplane with wing mounted engines experiences an engine failure the failure of which engine will cause the greatest control problem ?

The right outboard engine.

In case of a failure of one engine the aircraft will yaw on the side where the engine failure occurswith wind the yaw movement will see the aircraft nose coming into the wind the aircraft tends to face the wind due to the large surface area of his vertical fin with a strong crosswind from the right in order to counteract this tendency you must apply rudder to the left now if the right outboard engine fails thrust from the left engines will combined and it might be impossible to counteract the turning moment com encom080 646jpg

Question 265-29 : In general directional controllability with one engine inoperative on a multi engine aeroplane is adversely affected by 1 high temperature2 low temperature3 aft cg location4 forward cg location5 high altitude6 low altitudethe combination that regroups all of the correct statements is ?

2 3 6.

It's because thrust is lower in the less dense air high temperature and high altitude so the asymmetric effect is lessenednow with regards to the centre of gravity we have to take into account the perpendicular distance whether forward or aft the position of the centre of gravity doesn't affect the perpendicular distance from the thrust line created by the live engine to the aircraft's longitudinal axis about which the centre of gravity moves if we look at the perpendicular distance from the lift force generated by the rudder as the force is at an angle to the longitudinal axis assuming the rudder is deflected to counteract the moment from the live engine an aft centre of gravity would reduce the perpendicular distance and so reduce the moment created by the ruddervmca speed is cas based so engine thrust is reduced but control forces and effects on the rudder remain unaffected in a less dense atmosphere

Question 265-30 : The most aft cg location may be limited by 1 insufficient stick force stability2 insufficient flare capability3 excessive in flight manoeuvrability4 insufficient in flight manoeuvrabilitythe combination that regroups all of the correct statements is ?

1 3.

Because an aft cg equals less longitudinal stability makes the aircraft respond too rapidly which is the same thing as having too low a stick force per g and is the same thing as having too much manoeuvre ability and vice versa where a forward cg makes a sluggish aircraft and for example may leave you unable to raise the nose for landing

Question 265-31 : An example of a combined lateral and directional aperiodic motion is a ?

Spiral dive.

A spin may be defined as an aggravated stall that results in what is termed 'autorotation' wherein the airplane follows a downward corkscrew path as the airplane rotates around a vertical axis the rising wing is less stalled than the descending wing creating arolling yawing and pitching motion the airplane is basically being forced downward by gravity rolling yawing and pitching in a spiral path com encom080 684jpg'periodic' means recurring at regular intervals 'aperiodic' adds the greek prefix 'a' meaning 'not' or 'without''dutch roll' 'phugoid' and 'short period oscillation' are continuous oscillations with a period of oscillation a spiral dive is a continuous divergence

Question 265-32 : An aeroplane's bank angle is defined as the angle between its ?

Lateral axis and the horizontal plane.

Question 265-33 : Low speed pitch up can be caused by a significant thrust ?

Increase with podded engines located beneath a low mounted wing.

com encom080 690jpglow speed flight means an increasing angle of attack the centre of pressure moves forward the cg and the horizontal stabilizer must produce lift instead of producing a downforce in normal cruise flight lift generates by the horizontal stabilizer is affected by the disturbed flow from the wing and if you increase thrust additional arm moment comes in force due to the podded engines located beneath the cg

Question 265-34 : When a jet transport aeroplane takes off with the cg at the forward limit and the trimmable horizontal stabiliser ths is positioned at the maximum allowable nose up position for take off ?

Rotation will be normal using the normal rotation technique.

The forward cg limit is defined as the most nose heavy loading condition that will allow the aircraft to be rotated on takeoff and flared upon landing futhermore if trimmable horizontal stabiliser ths is positioned at the maximum allowable nose up position for take off rotation will be normal using the normal rotation technique

Question 265-35 : When a jet transport aeroplane takes off with the cg at the aft limit and the trimmable horizontal stabiliser ths is positioned at the maximum allowable nose up position for take off ?

Early nose wheel raising will take place.

Question 265-36 : Negative tail stall is ?

A sudden reduction in the downward aerodynamic force on the tailplane.

Question 265-37 : Which statement about negative tail stall is correct ?

When negative tail stall occurs the aeroplane will show an uncontrollable pitch down moment.

Negative tail stall is a sudden reduction in the downward aerodynamic force on the tailplane it means that previously the tail was producing a downward force cg is forward of cp com encom080 699jpg

Question 265-38 : An aeroplane has static directional stability if when in a sideslip with the relative airflow coming from the left initially the ?

Nose of the aeroplane tends to yaw left.

A side slip to the left is the slip of the tail to the left the nose goes rightif an aeroplane has static directional stability the intial tendency is to come back in the flight pattern of the aircraft through the air the nose of the aeroplane is to move to the left com encom080 1085jpgdirectional stability is accomplished by placing a vertical stabilizer or fin to the rear of the centre of gravity on the upper portion of the tail section

Question 265-39 : As the stability of an aeroplane decreases ?

Its manoeuvrability increases.

Question 265-40 : Aeroplane manoeuvrability increases for a given control surface deflection when ?

Ias increases.

The capability of an airplane to respond to the pilot's control greatly depends on the airflow speed on the control surface