British Young Pilots ¡ Flying Training ¡ Module FT-6.1
Think of riding a bike along a flat, straight road. You keep the handlebars steady and you do not go up or down any hills. An aeroplane flying straight and level does the same two things at once. Straight means it keeps pointing the same way: wings level, nose not swinging left or right. Level means it stays at the same height.
Try it: arms out as wings, hold them level, and walk a straight line across the room. That is the pilot's job in the cruise, and doing it neatly is one sign of a good pilot.
Source: Pooleys Vol 1 (15th ed.) p.77.
Attitude is simply how the aeroplane is positioned against the horizon: nose up, nose down or level, and wings level or tipped into a bank. Hold a model aeroplane out at arm's length and look at it against the top edge of the classroom wall (that is your horizon). Tip the nose up: a nose-high attitude. Tip it down: nose-low. Dip one wing: a bank.
In a real cockpit the pilot watches where the horizon sits against the nose of the aeroplane, and learns exactly where it should be for cruising.
Source: Pooleys Vol 1 (15th ed.) p.82 and p.84â85.
Performance is what you get: how fast you are going, and whether you are climbing, level or descending. Two things decide it together: the power (how hard the engine is working) and the attitude (where the nose is pointing). Think of a bicycle on a hill: you need the right angle and enough pedalling.
Pilots say it as a rule: POWER plus ATTITUDE equals PERFORMANCE. Leave the power alone and the nose decides: too high and the aeroplane climbs, too low and it descends, and the one right attitude in between keeps it level. Need a big change of height? Then the power has to change too.
Source: Pooleys Vol 1 (15th ed.) p.83, p.86 and p.88.
Pilots keep their eyes outside most of the time: looking for other aircraft, and checking that the horizon is level and sitting in the right place against the nose. Then a quick peek inside, one or two seconds only. The altimeter says whether the height is holding, and the VSI (vertical speed indicator) says whether you are drifting up or down.
There is also the balance ball: keep it in the middle with your feet on the rudder pedals. The work cycle is Lookout, Attitude, Instruments, over and over. Small, early corrections beat big, late ones.
Source: Pooleys Vol 1 (15th ed.) p.83â84, p.87 and p.90.
Straight is a constant heading: wings level with aileron, yaw prevented with rudder. Level is a constant altitude: the correct power set and the nose held in the correct attitude, altitude read on the altimeter. In balance is the balance ball kept centred with rudder pressure.
In steady straight and level flight the four forces are in equilibrium: lift opposes weight, thrust opposes drag. They rarely cancel exactly, so the tailplane and elevator add a small balancing force, usually downward, which the pilot adjusts continually with the control column. Reduce the power and the nose tends to drop unless back pressure is held.
STRETCHWhy does the nose drop when power comes off? Two reasons hide in the design: the thrust and drag couple no longer counters the lift and weight couple, and less propwash over the tailplane means less tail-down force (a smaller effect on a T-tail).
Source: Pooleys Vol 1 (15th ed.) p.77â78.
Angle of attack is the angle at which the relative airflow meets the wing. Pitch attitude is the nose position against the horizon. They are not the same thing. The elevator controls angle of attack: ease back and the nose rises, the wing meets the air at a greater angle, lift increases and the aeroplane starts to climb. Ease forward and the reverse happens. Slow flight needs a high angle of attack, fast flight a low one.
You cannot read angle of attack in the cockpit, so you set a suitable power and a suitable attitude instead. Power plus attitude determines performance: airspeed and rate of climb. At constant power one attitude gives level flight; nose too high and you climb, too low and you descend. Proof of the right attitude: the altimeter holds, with the VSI as backup.
Source: Pooleys Vol 1 (15th ed.) p.81â83.
Keep the wings level with aileron: the visual clue is the natural horizon lying level across the windscreen. Prevent yaw with rudder and keep the balance ball centred: ball out to the left, more left rudder; out to the right, more right rudder. Rudder trim, if fitted, removes the foot pressure.
Pick a reference point on the horizon ahead. In straight flight it stays in the same place relative to the nose, and inside the HI (heading indicator) and compass read steady. If you wander, first stop the drift (wings level, no yaw), then bank gently, about 5 degrees, back towards the point and neutralise the controls.
Do not fly with crossed controls: one wing down held straight with opposite rudder is a sideslip, adding drag and costing airspeed or fuel. A sloping cloud base is the classic trap. Ball to the centre with rudder, then straight with aileron.
Source: Pooleys Vol 1 (15th ed.) p.83â84, p.86 and p.89.
Level flight is the correct nose attitude for the power set: the horizon sits at a particular position against the nose cowl or coaming. Use the same seating position every flight so that picture stays reliable. With cruise power set, place the nose in the cruise attitude, let the airspeed settle on the ASI, cross-check altimeter and VSI, then trim off the elevator pressure while holding the attitude.
Climbing? Lower the nose slightly, regain the altitude, reselect the level attitude, retrim. Descending? Raise the nose, regain, reselect, retrim. Small early corrections beat occasional large ones; if the error grows beyond about 100 ft, consider using power.
Eyes outside most of the time: look out for traffic, check the attitude, then a one or two second glance at the instruments. Work cycle: Lookout, Attitude, Instruments (LAI).
Source: Pooleys Vol 1 (15th ed.) p.84â90.
Stability is the aeroplane's built-in tendency to return to its original attitude after a disturbance with no pilot input. In pitch it comes from the tailplane: a gust that raises the nose presents the tailplane to the airflow at a greater angle of attack, it makes more upward (or less downward) force, and the nose comes back down, exactly like the flights on a dart. In yaw the fin does the same job. In roll, a dropped wing tilts the lift and the aeroplane slips towards the low wing; high keel surfaces (fin, fuselage side) and dihedral turn that sideways airflow into a restoring roll.
Stability is weaker in roll and yaw than in pitch, and an uncorrected disturbance in either eventually becomes a spiral descent. The CG position sets pitch stability: a forward CG gives more stability but heavier elevator forces and, at landing speed, perhaps not enough elevator to flare; an aft CG gives less stability, constant attention to pitch, and at low speed a tail-heavy moment that can stall the aeroplane, possibly unrecoverably. The CG must stay within the Flight Manual's approved range: the pilot's responsibility.
Source: Pooleys Vol 1 (15th ed.) p.78â81.
Tap a card to flip it.
One item at a time. Is it an ATTITUDE (where the aeroplane sits against the horizon) or a PERFORMANCE (what you get: airspeed, height, climb or descent)? Tap to sort it.