Airbus trim
qzqsd· 30 dec
Heren,
simpele vraag: heeft de Airbus een automatische trim tijdens het manueel vliegen?
Volgens mij heeft een bus geen artificial feel op de stick waardoor je geen trim nodig hebt om krachten weg te trimmen, maar dit zou dan ook betekenen dat de je niet de neus manueel in een bepaalde positie kunt zetten en dan de stick lost kunt laten zonder dat hij zich zelf weer herstelt (stabiliteit)...
Of wordt hij toch automatisch uitgerimd naar gelang van de positie van de stick, zodat wanneer je de stick (theoretisch) los zou laten de neus in die positie blijft staan?
Mischien een beetje omslachtig verwoord maar get my drift?
5 REACTIESsimpele vraag: heeft de Airbus een automatische trim tijdens het manueel vliegen?
Volgens mij heeft een bus geen artificial feel op de stick waardoor je geen trim nodig hebt om krachten weg te trimmen, maar dit zou dan ook betekenen dat de je niet de neus manueel in een bepaalde positie kunt zetten en dan de stick lost kunt laten zonder dat hij zich zelf weer herstelt (stabiliteit)...
Of wordt hij toch automatisch uitgerimd naar gelang van de positie van de stick, zodat wanneer je de stick (theoretisch) los zou laten de neus in die positie blijft staan?
Mischien een beetje omslachtig verwoord maar get my drift?
ukpilot· 30 decje kan de stick gewoon loslaten !
De airbus heeft bijna altijd automatische trim.
Wat niet kan is meer dan 33graden bank en dan de stick loslaten dan gaat die namelijk automatisch weer terug naar 33 graden. In normal law kan je ook niet meer dan 67 graden bank geven. Dit kan wel in Alternate law, oftwel je bent meerdere flight computers kwijt.
Voor pitch kun je maximaal 30 nose up en 15 nose down geven en dan de stick loslaten hij blijft deze attitude gewoon aanhouden totdat of de overspeed of stall protection in werking treed.
De airbus heeft bijna altijd automatische trim.
Wat niet kan is meer dan 33graden bank en dan de stick loslaten dan gaat die namelijk automatisch weer terug naar 33 graden. In normal law kan je ook niet meer dan 67 graden bank geven. Dit kan wel in Alternate law, oftwel je bent meerdere flight computers kwijt.
Voor pitch kun je maximaal 30 nose up en 15 nose down geven en dan de stick loslaten hij blijft deze attitude gewoon aanhouden totdat of de overspeed of stall protection in werking treed.
30 dec
TopSwiss 737· 30 decZie normal law op de bus als een soort Control Wheel Steering op een conventionele kist...
Sidestick went overigens heel snel; binnen 2 circuitjes in de sim heb je het al aardig door.
In direct law moet je wel zelf trimmen, er staat dan ook in grote amber letters "USE MAN PITCH TRIM" op de PFD.
Als het echt je dag niet is en je moet in mechanical backup vliegen dan heb je zelfs geen manual trim meer en krijg je dus een lam handje want je moet continue sidestick input geven...
Maar gelukkig zegt het FCOM "short periods":
MECHANICAL BACKUP
The pilot can use the pitch trim and rudder to control the aircraft for short periods of total loss of fly-by-wire.
Sidestick went overigens heel snel; binnen 2 circuitjes in de sim heb je het al aardig door.
In direct law moet je wel zelf trimmen, er staat dan ook in grote amber letters "USE MAN PITCH TRIM" op de PFD.
Als het echt je dag niet is en je moet in mechanical backup vliegen dan heb je zelfs geen manual trim meer en krijg je dus een lam handje want je moet continue sidestick input geven...
Maar gelukkig zegt het FCOM "short periods":
MECHANICAL BACKUP
The pilot can use the pitch trim and rudder to control the aircraft for short periods of total loss of fly-by-wire.
30 dec
19 of 77· 30 decJUst a small correction
JUst a small correction
Mechanical backup has nothing to do with the sidestick - see the last line in your post. You have manual pitch trim and rudder pedals to fly the aircraft. Side stick is useless.
Use man pitch trim will be annunciated in red of the PFD.
The best explanation of the contol laws I have ever seen can be found
here . Download the free UAL control laws file.
JUst a small correction
Oorspronkelijk gepost door TopSwiss 737
Als het echt je dag niet is en je moet in mechanical backup vliegen dan heb je zelfs geen manual trim meer en krijg je dus een lam handje want je moet continue sidestick input geven...
Maar gelukkig zegt het FCOM "short periods":
MECHANICAL BACKUP
The pilot can use the pitch trim and rudder to control the aircraft for short periods of total loss of fly-by-wire.
Mechanical backup has nothing to do with the sidestick - see the last line in your post. You have manual pitch trim and rudder pedals to fly the aircraft. Side stick is useless.
Use man pitch trim will be annunciated in red of the PFD.
The best explanation of the contol laws I have ever seen can be found
here . Download the free UAL control laws file.
30 dec
TopSwiss 737· 31 decThanks 19of77, I stand corrected...
Zat zelf al een beetje te twijfelen toen ik het poste; niet echt doordacht.
Zie nu idd dat het verhaal niet klopt, tegenstrijdige opmerkingen... Wat zakt die theorie snel weg als je een tijdje die kist niet vliegt!
De hele tekst:
ABNORMAL CONTROL LAWS - GENERAL
ALTERNATE LAW
Pitch alternate and roll direct is the first level of degraded control law, resulting from some double failures.
The autopilot may be available, depending on the cause and type of failure(s).
DIRECT LAW
The sidestick is directly coupled to the controls via the computers, but without any of the stabilization feedbacks. In effect, this law turns the aircraft into a conventional aircraft, but is compensated for configuration and CG. The pilot must use manual pitch trim, as is signaled on the PFD. The autopilot is not available.
MECHANICAL BACKUP
The pilot can use the pitch trim and rudder to control the aircraft for short periods of total loss of fly-by-wire.
ABNORMAL CONTROL LAWS - IN DETAIL
ALTERNATE LAW
Pitch
Alternate law in pitch is almost the same (for the pilot) as the normal control laws.
However, alternate law does not maintain any of the protections, except for the load factor limitation. As a result, the pilot must fly the aircraft more attentively to avoid inadvertently exceeding the normal limits.
Alternate law reduces VMO to 320 knots to restore a normal aircraft speed margin in case of upset. This is not necessary in the Mach range, because the margin there is, in any case, conventional.
An aural "STALL, STALL, STALL" warning sounds at low speeds. Upon hearing it, the pilot must return to the normal operating speed by taking conventional actions with the controls:
THRUST LEVERS . TOGA
At the same time :
PITCH ATTITUDE . REDUCE
BANK ANGLE . ROLL WINGS LEVEL
SPEEDBRAKES . CHECK RETRACTED
If a danger of ground contact exists, reduce pitch attitude no more than necessary to allow the airspeed to increase. After initial recovery, maintain speed close to VSW, until it is safe to accelerate.
If below 20000 feet, and if in clean, select FLAP 1.
Out of stall, when no threat of ground contact :
LANDING GEAR . UP
Recover to normal speeds, and select flaps are required.
In case of one engine inoperative, use power and rudder with care.
The aural stall warning may also sound at high altitude, where it warns that the aircraft is approaching the angle of attack for the onset of buffet. To recover, the pilot must relax the back pressure on the sidestick and reduce the bank angle, if necessary. When the stall warning stops, the pilot can increase the back pressure again, if necessary, to return to the planned trajectory.
At low speed the change in the speed scale is very noticeable. VLS remains, but V PROT and V MAX disappear, replaced by a single black and red strip the top of which is stall warning speed. Unlike VLS which is stable, VSW is g sensitive so as to give additional margin in turns.
As mentioned above, ALTERNATE reverts to DIRECT law for landing when the flight crew lowers the landing gear.
Roll
Roll control is direct. The rate of roll is generally higher than with normal law and at first the aircraft appears to be very sensitive.
Bank stability and protections are no longer active and the flight crew should take care to stay within normal limits.
DIRECT LAW
Normally direct law in pitch is transitory, due to undetected failures of, for example, a second IRS. Once the flight crew has isolated the failed system, it can reset the ELACs to acquire alternate law in pitch.
When the system goes into direct law, "USE MAN PITCH TRIM" appears on the PFDs. This message flashes for 5 seconds, then becomes steady.
The pilot should use small control inputs when the aircraft is in direct law at high speed, because the controls are powerful. Good trimming in pitch is required.
The pilot should avoid using large thrust changes or sudden speedbrake movements, particularly if the center of gravity is aft. If the speedbrakes are out and the aircraft has been retrimmed, the pilot should retract the speedbrakes gently, giving time to retrim so as to avoid a large nose-down trim change.
The flight crew must fly the aircraft carefully at all times. Control is precise, but there are no protections.
The aural stall warning for alternate law also serves direct law, and the technique for recovery is the same.
Any tendency to roll stick free can be corrected by conventional use of rudder. Residual rudder forces can be trimmed out by using rudder trim in the direction of the applied force.
After trimming, the sideslip index will be slightly displaced from center. With some failure conditions the asymmetric rolling tendency may be increased. It will always be possible to trim the aircraft to fly straight, hands off. There may then be an asymmetry in roll response, but the roll rate achieved is always adequate.
Landing in direct law is like landing a conventional aircraft. Trim changes to compensate for configuration changes are small, as is the trim change with speed change. Trim change with a large thrust change is quite large, so the pilot should make smooth thrust changes. The flare height for landing is the same (20 feet), and the pilot uses conventional techniques. (The controls remain light and powerful).
Pilots have landed this aircraft in direct law in moderate to heavy turbulence with gusting winds without undue difficulty.
Direct law works with or without the yaw damper. The aircraft is always convergent in dutch roll, so if an oscillation begins it will stop itself if not excited. To stop dutch roll the pilot should use lateral inputs, not rudder.
Zat zelf al een beetje te twijfelen toen ik het poste; niet echt doordacht.
Zie nu idd dat het verhaal niet klopt, tegenstrijdige opmerkingen... Wat zakt die theorie snel weg als je een tijdje die kist niet vliegt!
De hele tekst:
ABNORMAL CONTROL LAWS - GENERAL
ALTERNATE LAW
Pitch alternate and roll direct is the first level of degraded control law, resulting from some double failures.
The autopilot may be available, depending on the cause and type of failure(s).
DIRECT LAW
The sidestick is directly coupled to the controls via the computers, but without any of the stabilization feedbacks. In effect, this law turns the aircraft into a conventional aircraft, but is compensated for configuration and CG. The pilot must use manual pitch trim, as is signaled on the PFD. The autopilot is not available.
MECHANICAL BACKUP
The pilot can use the pitch trim and rudder to control the aircraft for short periods of total loss of fly-by-wire.
ABNORMAL CONTROL LAWS - IN DETAIL
ALTERNATE LAW
Pitch
Alternate law in pitch is almost the same (for the pilot) as the normal control laws.
However, alternate law does not maintain any of the protections, except for the load factor limitation. As a result, the pilot must fly the aircraft more attentively to avoid inadvertently exceeding the normal limits.
Alternate law reduces VMO to 320 knots to restore a normal aircraft speed margin in case of upset. This is not necessary in the Mach range, because the margin there is, in any case, conventional.
An aural "STALL, STALL, STALL" warning sounds at low speeds. Upon hearing it, the pilot must return to the normal operating speed by taking conventional actions with the controls:
THRUST LEVERS . TOGA
At the same time :
PITCH ATTITUDE . REDUCE
BANK ANGLE . ROLL WINGS LEVEL
SPEEDBRAKES . CHECK RETRACTED
If a danger of ground contact exists, reduce pitch attitude no more than necessary to allow the airspeed to increase. After initial recovery, maintain speed close to VSW, until it is safe to accelerate.
If below 20000 feet, and if in clean, select FLAP 1.
Out of stall, when no threat of ground contact :
LANDING GEAR . UP
Recover to normal speeds, and select flaps are required.
In case of one engine inoperative, use power and rudder with care.
The aural stall warning may also sound at high altitude, where it warns that the aircraft is approaching the angle of attack for the onset of buffet. To recover, the pilot must relax the back pressure on the sidestick and reduce the bank angle, if necessary. When the stall warning stops, the pilot can increase the back pressure again, if necessary, to return to the planned trajectory.
At low speed the change in the speed scale is very noticeable. VLS remains, but V PROT and V MAX disappear, replaced by a single black and red strip the top of which is stall warning speed. Unlike VLS which is stable, VSW is g sensitive so as to give additional margin in turns.
As mentioned above, ALTERNATE reverts to DIRECT law for landing when the flight crew lowers the landing gear.
Roll
Roll control is direct. The rate of roll is generally higher than with normal law and at first the aircraft appears to be very sensitive.
Bank stability and protections are no longer active and the flight crew should take care to stay within normal limits.
DIRECT LAW
Normally direct law in pitch is transitory, due to undetected failures of, for example, a second IRS. Once the flight crew has isolated the failed system, it can reset the ELACs to acquire alternate law in pitch.
When the system goes into direct law, "USE MAN PITCH TRIM" appears on the PFDs. This message flashes for 5 seconds, then becomes steady.
The pilot should use small control inputs when the aircraft is in direct law at high speed, because the controls are powerful. Good trimming in pitch is required.
The pilot should avoid using large thrust changes or sudden speedbrake movements, particularly if the center of gravity is aft. If the speedbrakes are out and the aircraft has been retrimmed, the pilot should retract the speedbrakes gently, giving time to retrim so as to avoid a large nose-down trim change.
The flight crew must fly the aircraft carefully at all times. Control is precise, but there are no protections.
The aural stall warning for alternate law also serves direct law, and the technique for recovery is the same.
Any tendency to roll stick free can be corrected by conventional use of rudder. Residual rudder forces can be trimmed out by using rudder trim in the direction of the applied force.
After trimming, the sideslip index will be slightly displaced from center. With some failure conditions the asymmetric rolling tendency may be increased. It will always be possible to trim the aircraft to fly straight, hands off. There may then be an asymmetry in roll response, but the roll rate achieved is always adequate.
Landing in direct law is like landing a conventional aircraft. Trim changes to compensate for configuration changes are small, as is the trim change with speed change. Trim change with a large thrust change is quite large, so the pilot should make smooth thrust changes. The flare height for landing is the same (20 feet), and the pilot uses conventional techniques. (The controls remain light and powerful).
Pilots have landed this aircraft in direct law in moderate to heavy turbulence with gusting winds without undue difficulty.
Direct law works with or without the yaw damper. The aircraft is always convergent in dutch roll, so if an oscillation begins it will stop itself if not excited. To stop dutch roll the pilot should use lateral inputs, not rudder.
31 dec
Phoenix_X· 1 janDus RTO, het simpele antwoord op je simpele vraag is: Ja. :D
1 jan