8

Moving each part has different effect on drag: Moving just the elevator increases camber, producing large force which is useful for manoeuvring, but it also produces more drag. Moving the whole stabilizer, keeping the camber low, produces less drag for the same force, which is good for cruise efficiency. That's why the elevator is used for control and the ...


7

When I was type rated in the CRJ200 with hydraulic controls and a THS, directly coming from light aircraft, the differences in technique are significant and it was definitely something new to learn. With a THS, column neutral is always the same spot. This means trimming to a speed is not a case of moving the control to location X and trim until it stays at ...


6

Drag is one main reason, as outlined in @JanHudec's answer; the other one is maneuverability given the fairly wide CG range that exists on modern transport category aircraft. Without horizontal stabilizer, elevator may be insufficient for maneuvering at forward CG. One probable limitation would be the compliance with 14 CFR 25.107(e)(3) and (4), where prompt ...


5

Flutter is the main reason why the horizontal tail on Antonov designs is mounted low. Many other transport airplanes do indeed sport a T-tail (C-141, Il-76, C-5, C-17, A400M). Cargo airplanes with a rear ramp suffer from low torsional stiffness of the rear fuselage because of that large cut-out for the ramp doors. If the ramp doors are locked with many ...


4

There are a few reasons, the first is that the leading edge of the wing will be eroded in service by flying through dust, sand rain, hail etc. Metals are always typically used on such surfaces (termed an 'erosion shield') to reduce this effect, and also because minor damage can be polished out to keep the aircraft looking nice. Aluminum isn't the hardest ...


3

There is nothing too special about the MiG-29 stabilator. The "slanted" (swept) axis of rotation is fairly common: as far as I remember, all MiGs that had a stabilator had this arrangement. This has primarily structural advantages: it is easier to integrate the shaft (or axle) along the structural elements of the stabiliser, making it lighter. Also,...


3

The ideal cruise condition, which minimises induced drag, is for the tail to exert zero lift. This avoids any wasteful tip vortices from the tail. However for most planes the CG shifts during flight, if only because fuel is being used up. Also, trim conditions change with speed, rate of climb, altitude and a host of other variables during flight. The tail ...


2

If the question is understood to encompass any form of horizontal stabilizer which may be adjusted in flight (with or without a separate movable elevator), then the answer would appear to be Sir George Cayley's 1849 full-sized glider which briefly took flight-- see http://www.flyingmachines.org/cayl.html. The Wright brothers also used all-moving horizontal ...


2

The horizontal tail surface is there to generate downforce that holds the nose up in cruise. Without it, the faster you go, the more the nose points down as the machine's body wants to "trail" so to speak behind the tilted rotor disc. The vertical tails are to provide a weathervaning effect to make the machine passively point ahead in forward ...


2

They are very strong and reliable. Occurences where they are completely broken off are extremely few and far apart, and in the cases that have happened, usually some kind of abuse took place, such as too harsh control inputs from pilots. In the case of American Airlines flight 587, the control system was also a contributing factor. Lesser damages, such as ...


2

What you see here is not the actual stall of the horizontal stabilizer but the "rudder rattle" that indicates that the stall of the main wings is just about to happen. Airplanes are designed to have this "rudder rattle" as a mechanical way to warn the pilot.


1

On August 12, 1985, a Boeing 747SR operating as Japan Airlines Flight 123 lost its vertical stabilizer and crashed after the aircrew had struggled for 32 minutes to control the stricken airliner. It is the deadliest single-aircraft accident in aviation history; 498 of 502 aboard were killed.


1

Safety is absolute paramount in aviation. There is no industry in existence that has a higher safety standard than aviation. Aviation operates so called idiot proof systems. Routines that completely eliminate the possibility of failure. Pilots are never ever done learning to fly safe. In highly realistic simulator flights, pilots are taken through any ...


1

The further aft the stabilator is, the longer the moment arm, which means they can be smaller and still have the required pitch moment. But if the majority of the stabilator surface is behind the aircraft fuselage, (as in this case), then, even when the rotation axis is swept back, as it is on many Mig aircraft, the bulk of the aerodynamic surface can be ...


1

The horizontal stabilizer on an AN-124 is not directly behind the wings. It is slightly lower than the root of the wings, and the wings have a significant anhedral angle, which effectively eliminates the effect of turbulent airflow from the wings on the stabilizer.


1

Consider an arrow. Its center of pressure is behind the middle of the arrow due to the fletching (feathers) at its back (aft) end, but its center of gravity is close to the middle. If it isn't pointing directly into the path it is taking, the center of pressure, being behind the center of gravity, pushes in the direction to restore it to pointing where it is ...


1

It would appear to be the Boeing 707/720, followed by the DC-8. Lots of GA airplanes derive pitch trim and static stability from the stab surface, that is operated manually by a screw jack driven by the trim wheel, and only use elevator for maneuvering inputs (having no trim tab, it just trails when hands off). Significant ones that come to mind are the ...


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