[quote="Čondra87"]
K tomu vzletu. - Ještě Ti nikdo neřekl, že letadlo se zvedá přitahováním? :-) Vr=Rotate = Rychlost, při ketré se pomalu 3°/s přitahuje, letadlo se plyně odletpí. Přitahování se zastaví cca na 15°(Matika je to cca 5 sekund)
A pak to letí.[/quote]
Kde si prisel na tech
15? Pritahuje se max na 10, aby si nezavadil ocasem o drahu, dal jak pise ADIO.
[quote="AJS"]
-Rotace se zahajuje při rychlosti Vr, ryclostí cca 3°/s. U 737 by tímhle způsobem mělo dojít k odlepení při cca 10°podélného sklonu. Rychlosti V2 musí být dosaženo do výšky 35ft (na suché dráze), zpravidla se ale letadlo odlepí až za ní. V průběhu rotace se nesmí pro pilotáž používat F/D! Po odlepení se přitahuje na rychlost V2+15, k tomu už se F/D používat může (u 737 ale třeba F/D vede na V2+20). Touhle rychlostí se má stoupat bez ohledu na to, jestli používáme F/D nebo ne. POZOR! Při pomalé rotaci, pod 3°/s, nebo při velmi lehkém letadle, se stává, že rychlost vzroste víc než na V2+20. Metodika, konkrétně tedy Flight Crew Training Manual (FCTM) Boeingu, říká, že v takovém případě se má letět s takovým podélným sklonem, při kterém rychlost už dál neroste, i když F/D vede na větší úhel! Hrozí totiž buď překročení maximálního podélného sklonu 20°, nebo velký pokles rychlosti, na který s ohledem na setrvačnosti nemusí být čas zareagovat. [/quote]
[quote="ČSAV SOP B737"]
When F/Os calls out „ROTATE“, pull smoothly the yoke to start rotation; the speed of rotation should be 3 degrees/sec and maximum bank 10° to avoid tailstrike[/quote]
[quote="Continental B737 Flight Manual"]
ROTATION AND LIFTOFF
As the airspeed approaches V1, the slight forward control column pressure is
relaxed to neutral, allowing for a smooth rotation to begin at VR.
At VR, rotate smoothly with one continuous motion approximating, but no more
than 2.5 degrees/sec. Using the normal rotation rate, the aircraft flies off the
runway as the pitch attitude increases, and a runway to fuselage clearance of
approximately 20 inches results.
Rotate initially toward a 15-degree attitude. This will result in an airspeed of
approximately V2 + 20 knots. Initially, the Flight Director will command 15
degrees nose up. However, the F/D pitch command will not be used during
rotation. Indicated airspeed and vertical speed are the primary instruments.
After the radio altitude and vertical speed increase, the Pilot Flying will adjust
pitch to coincide with F/D input. This pitch command under normal situations
will be V2 + 20 knots. The Flying Pilot will maintain the F/D input of V2 + 20
until reaching initial flap retraction altitude.
At light gross weights, an initial climbout at V2 + 20 will produce an excessive
deck angle. A slight difference between aircraft symbol and F/D pitch
command will be necessary to not exceed 25 degrees of pitch. This pitch limit
is for passenger comfort. The F/D pitch command will become synchronized
with the aircraft symbol as the flaps are retracted during acceleration to clean
maneuvering speed.
Because the aircraft is geometrically limited, it cannot be rotated to a body angle
that will prevent it from becoming airborne with takeoff thrust. Premature
rotation will probably result in the aircraft becoming airborne before the normal
liftoff point, and at a slower than normal speed. Since this speed will be
considerably below the best angle of climb speed, the initial climb profile may
be greatly reduced.
The aircraft has a very low angle of attack on the ground in three-point attitude.
Delaying rotation (waiting for the aircraft to “Fly Itself” off the ground) will
increase the liftoff distance considerably.
The airspeed indicator will lag momentarily during rotation due to the vertical
movement of the static ports relative to the direction of flight as the nose is
lifted.
When a positive rate of climb has been verified on the IVSI and altimeter, either
pilot will call, “POSITIVE RATE.” When a positive rate of climb is confirmed,
the Pilot Flying will call “GEAR UP,” stabilize airspeed at V2 + 20 knots, and
transition to the F/D pitch command.
In roll, the F/D commands wings level to 400 feet RA, then selected bank angle
limit to the selected heading when a new roll mode is selected.
Selection of pitch and roll modes other than TOGA are inhibited below 400 feet
RA.
During takeoff or initial climb, if a center tank LOW PRESSURE light(s)
illuminates, the center tank pump(s) may remain on until the climb attitude is
reduced and the light(s) extinguishes or workload allows for the pump(s) to be
positioned to OFF. When established in a level attitude at cruise, if the center
tank contains usable fuel and the center tank switches are off, center tank pump
switches may be positioned to ON again. Verify the LOW PRESSURE light
extinguish and position both switches to OFF when both LOW PRESSURE lights
illuminate.[/quote]
