747 Landing technique
PPRuNe Person
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Not really
The crosswind landing technique is probably the same on a 747 or similar wide body as a B737
The 747 has its own special problems due to the configuration, ie wingsweep and pod ground clearance. On a 737, get to just above runway, chop power, both hands on wheel, wrestle it to the ground, don't worry about bank too much. On a 747, gradually reduce thrust in flare until levers reach idle stops at touchdown, simultaneously remove drift with rudder and maintain absolute wings level with wheel. More than 6 degrees of bank at this satge and you'll scrape a pod. The outer portion of the wings with engines 1 & 4 flexes downwards at touchdown as the lift comes off the wing, reducing the ground clearance.
If you try and land a 747 like a 737 you'll scrape metal.
This old chestnut just runs and runs ..........
Since most initial flight training starts on single engined aircraft, the forced landing technique requires that pitch for speed control be taught (ie. no engine available) however, moving on, with multi and jet aircraft, a combination of techniques is subconsciously employed whereby the pilot is generally using the same technique as the autoflight systems.
Since most initial flight training starts on single engined aircraft, the forced landing technique requires that pitch for speed control be taught (ie. no engine available) however, moving on, with multi and jet aircraft, a combination of techniques is subconsciously employed whereby the pilot is generally using the same technique as the autoflight systems.
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This is one for all the 'Pitch for Speed, Power for Rate of Altitude change', (in a swept wing podded engine jet, ie. 747 ) brigade.
Sit at the end of a runway in a 747, pull the column back to make it accelerate down the runway and bring the thrust up out of idle to make it climb away.
When you can do that, I'll be a believer.
Sit at the end of a runway in a 747, pull the column back to make it accelerate down the runway and bring the thrust up out of idle to make it climb away.
When you can do that, I'll be a believer.
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Sweet. Says it all.
The problem for folk is that in essence, it's not easy to prove that the same controls in every aircraft do the same thing. Houses smaller, houses bigger, etc. I used to teach power for speed from the start as it was more logical, but also show the other method when one of the variables was fixed. Works for forced landings and jammed elevators too- I also used to teach both methods of PFLs too and let the student choose which fitted their mental model..
B744 or C152, they're all aeroplanes (didn't mention Airbus there though
)
The problem for folk is that in essence, it's not easy to prove that the same controls in every aircraft do the same thing. Houses smaller, houses bigger, etc. I used to teach power for speed from the start as it was more logical, but also show the other method when one of the variables was fixed. Works for forced landings and jammed elevators too- I also used to teach both methods of PFLs too and let the student choose which fitted their mental model..
B744 or C152, they're all aeroplanes (didn't mention Airbus there though
)
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TK951 with its closed throttles and trimming pitch for altitude to stay on GS didn't work out so good. If the pitch trim had been used for speed instead of altitude, the closed throttles would have made it sink below GS sooner, and given the pilots, "Too Low, Glideslope" in time to make a recovery with the trim properly set for the speed.
Cute, Trent, but until it's planing through the air, it's not an airplane.
Cute, Trent, but until it's planing through the air, it's not an airplane.
Except for FBW Airbus, planes are trimmed for a speed, not an altitude. Flying along straight and level at 250 KIAS, ADD power to increase speed--what happens? The plane, whether a C150 or a B747, begins to climb in an attempt to maintain its trimmed speed. Pull back the throttles and it will descend.
Power + Attitude = Performance
Trent OK, trimmed for take-off, pour on the coals, what will happen at about V2? It should, discounting any negative angle of incidence, lift-off and try to maintain V2. Why didn't it lift off right away, you say. Because it hadn't reached its trimmed speed.
Airbus FBW is G-stable, not Speed-stable, so pitch controls speed doesn't apply. Please refer to M. DesCartes for reasons why they did that.
Power + Attitude = Performance
Trent OK, trimmed for take-off, pour on the coals, what will happen at about V2? It should, discounting any negative angle of incidence, lift-off and try to maintain V2. Why didn't it lift off right away, you say. Because it hadn't reached its trimmed speed.
Airbus FBW is G-stable, not Speed-stable, so pitch controls speed doesn't apply. Please refer to M. DesCartes for reasons why they did that.
For captains: Always remember and forever take heed; left hand for glidepath and right hand for speed!
Primary effects of controls apply.
Do what the autoflight does. If you get slow, put the power up (counter the underslung-pitchup if necessary). If you get high, stuff the nose down! As mentioned earlier by Unhooked, try staying on the glideslope of an ILS with the power and controlling speed with the stick. Entertainment-plus.
The reverse works in a C150 only because of the powerful secondary effect of controls.
True, but that's the secondary effect of controls eventually working. On final, we don't have time to wait. High? Stuff the nose down and then pull the power off a bit, anticipating the secondary effect of controls (push nose down, speed will eventually increase).
Primary effects of controls apply.
Do what the autoflight does. If you get slow, put the power up (counter the underslung-pitchup if necessary). If you get high, stuff the nose down! As mentioned earlier by Unhooked, try staying on the glideslope of an ILS with the power and controlling speed with the stick. Entertainment-plus.
The reverse works in a C150 only because of the powerful secondary effect of controls.
Originally Posted by Galaxy Flyer
Flying along straight and level at 250 KIAS, ADD power to increase speed--what happens? The plane, whether a C150 or a B747, begins to climb in an attempt to maintain its trimmed speed. Pull back the throttles and it will descend.
Cap'n Bloggs
Congratulations on the 3000th post, but
I do not aspire to fly like an autopilot, I trust you don't, either. My observations are based on a 1000 hours of T-Gs and approaches with students in the Galaxy, and another 10,000 in everything from the C-150 to the Galaxy.
Truth be told, it is hard to separate the two actions. If high, pulling off the power will require pushing the nose over and vice versa. But, we trim for airspeed and not for altitude.
GF
Congratulations on the 3000th post, but
I do not aspire to fly like an autopilot, I trust you don't, either. My observations are based on a 1000 hours of T-Gs and approaches with students in the Galaxy, and another 10,000 in everything from the C-150 to the Galaxy.
Truth be told, it is hard to separate the two actions. If high, pulling off the power will require pushing the nose over and vice versa. But, we trim for airspeed and not for altitude.
GF
