HEL AF AME

A helicopter in forward flight changes course by: varying the pitch of the tail rotor blades. tilting the tail rotor disk. varying the pitch of the main rotor blades. tilting the main rotor disk in the desired direction.

The vertical flight of a helicopter is controlled by: tilting the rotor disk. increasing or decreasing cyclic pitch. increasing or decreasing collective pitch. increasing or decreasing both cyclic and collective pitch.

A variation of the blade pitch as the blades rotate through the tip-path plane is controlled by: the collective pitch control. the cyclic pitch control. raising the advancing blade. lowering the advancing blade.

A rotor system having hinges at the root of each blades, which permits the blade to move up and down is known as: a rigid rotor. a semirigid rotor. a articulated rotor. a semiarticulated rotor.

A semirigid rotor is underslung in order to: decrease stability. increase stability. decrease rigidity. increase rigidity.

During a vertical flight at a steady rate: the sum of lift and thrust is equal to the sum of weight and drag. the sum of lift and weight is equal to the sum of thrust and drag. the sum of lift and thrust is greater than the sum of weight and drag. the sum of lift and weight is greater than the sum of thrust and drag.

A condition which is caused by the difference in airspeed between the advancing and retreating rotor blades is: dissymmetry of lift. coriolis effect. gyroscopic precession. translational lift.

Some types of rotor are permitted to flap to compensate for: coriolis effect. dissymmetry of lift. centrifugal force. blade tip overspeed.

Greater downwash effect through the aft part of the main rotor disk compared to the forward part of the disk is known as: ground effect. transitional lift. translational lift. transverse flow lift.

If a single-rotor helicopter is in horizontal flight, the angle of attack of the advancing blade is: less than the retreating blade. more than the retreating blade. equal to the retreating blade. the same at all points around the rotor disk.

The magnitude of the coning angle is determined by the relationship between the centrifugal force and: size of the tip path plane. the lift produced by the blades. the angle of attack of the blades. the axis of rotation of the rotor system.

Cyclic control inputs to the swashplate are not located at the point where the action is to occur, because: of gyroscopic precession. of swashplate rotation. of probable damage to the drive links. this would prevent tilting of the swashplate.

The torque developed by the main rotor is an example of: Newton’s first law. Newton’s second law. Newton’s third law. Newton’s fourth law.

Coriolis effect is associated with: the change in the coning angle. the rising of the advancing blade. gyroscopic precession. changes in the speed of rotation.

Ground resonance is a problem associated with: rigid rotors. semirigid rotors. fully articulated rotors/articulated rotors. non-articulated rotors.

During autorotation, the flow of air through the main rotor is: upward. downward. same as normal powered flight. dependent on the position of the cyclic stick.

During autorotation, on a conventional American designed helicopter, the tail rotor will be: at a negative pitch. at a positive pitch. at a neutral pitch. the same as normal flight.

To counteract torque during takeoff, conventional European-made helicopters require. right pedal to be added. left pedal to be added. the pedals to be held in the neutral position. left pedal to be added and maximum beep applied.

Translational lift is noticeable at around. 3 to 5 mph. 10 to 12 mph. 15 to 20 mph. 25 to 45 mph.

Horizontal stabilizers are shaped as: symmetrical airfoils. unsymmetrical airfoils. inverted symmetrical airfoils. inverted unsymmetrical airfoils.

Pitch link rod ends are usually fitted with: plain bearings. spherical bearings. sealed bearings. elastomeric bearings.

The conical elastrometric bearings used in rotor systems are capable of: providing movement about the three axes and absorbing heavy torsional loads. absorbing high radial loads and providing movement in radial oscillation. absorbing low axial and radial loads, and absorbing heavy torsional loads. absorbing high axial and radial loads with some movement in both directions.

In a hydraulic system, the purpose of the pump is to: move the fluid. relieve pressure. generate pressure. regulate pressure.

Hydraulic pumps used for high pressure output are normally: the vane type. the gear type. the piston type. the gerotor type.

In a hydraulic system, priority valves are: electrically actuated. hydraulically actuated. mechanically actuated. both electrically and hydraulically actuated.

The variation in the angle of incidence of a blade between the root and the tip is: the span angle. the chord angle. the twist angle. the feathering angle.

The skin on metal rotor blades. is bonded to the spar only. is simply a wrap-around giving the blade its aerodynamic shape. is the main structural component of the blade. acts as an abrasion shield to the blade.

Blade alignment establishes the correct relationship of the blade center of gravity to: the main spar. the spanwise balance. the chordwise balance. the center of pressure.

Rotor blade tracking is carried out to ensure that all blade tips: have the same angle of attack. have the same angle of incidence. follow the same tip path throughout the cycle of rotation. increase their angle of attack by the same degree when the collective is raised.

The vibration usually associated with track is: a 1:1 lateral vibration. a 1:1 vertical vibration. a 2:1 lateral vibration. a 3:1 vertical vibration.

If the amplitude of a vibration remains constant throughout the rpm range, the rotor is: serviceable. out of track. out of chordwise balance. out of spanwise balance.

One bad damper, on a fully articulated head, would result in: a 1:1 beat or scuffle. a 2:1 lateral vibration. a 2:1 vertical vibration. in both an out of track and balance condition.

In flight, the main rotor mast usually absorbs: tension loads. torsion loads. both torsion and radial loads. both torsion and tension loads.

Damage due to mast bumping is associated with: rigid rotor systems. semi rigid rotor systems. semi articulated rotor systems. fully articulated rotor systems.

On most helicopters, the rotating part of the swashplate is driven by a drive link attached to: the mast. the cyclic inputs. the collective inputs. the main transmission.

The collective twist grip on free turbine helicopters is used to control: the beep rpm. the turbine rpm. the compressor rpm. the rate of descent during engine failure.

Moveable horizontal stabilizers are used to: increase lateral cyclic control. decrease fore and aft cyclic control. decrease rigidity and shorten C. of G. range. increase controllability and lengthen the C. of G. range.

An overstable helicopter and delayed control response could be the result of: hard drag hinge dampers. soft stabilizer bar dampers. hard stabilizer bar dampers. improperly adjusted collective control.

During autorotation, seizing of the free wheeling unit would: allow the rotor to drive the engine. allow the engine to drive the rotor. allow the transmission to drive the rotor. have no effect.

On a turbine powered helicopter, the pressure required to operate the rotor brake is normally provided by: engine bleed air. engine oil pressure. a dedicated hydraulic system. transmission oil pressure.

On helicopters using hydraulic boosting of the flight controls, artificial feel is usually provided by: a gradient unit. a magnetic brake. a centrifugal brake. an irreversible valve.

Which statement is correct concerning “torque effect” on helicopters?. as horsepower increases, torque decreases. as horsepower decreases, torque increases. torque direction is opposite to rotor blade rotation. torque direction is the same as rotor blade direction.

Most helicopter fuel systems are: free flow systems. forced feed systems. gravity feed systems. suction feed systems.

The dual tachometer indicates: engine and main rotor rpm. engine and tail rotor rpm. engine and transmission rpm. compressor rpm and free turbine rpm.

Dynamic balancing of the tail rotor may be accomplished with: the Chadwick-Helmut Vibrex System. the Phasor only. both Phasor and the Vibrex. both the Phasor and the Strobex.

As the angle of attack of an airfoil decreases the ?. C of G will move forward. C of G will move afterward. Center of Pressure will move forward. Center of Pressure will move afterward.

What physical factors are involved in providing lateral stability?. Dihedral and wing sweep. Angle ot attack and seepback. Angle of attack and angle of incidence. Dihedral and ancle of incidence.

Stability about lateral axis is?. Vertical stabilíty. Horizontal Stability. Longitudinal stability. Lateral stability.

Strainds of control cable are found to be worn, but not blended together, cables could be replaced when worn.?. 10 %. 25 %. 40 ~50%. More than 60 %.

A newly built up wheel should?. Be deflated and Reinflated after ·12 hours. Be deflated and Reinflated after 24 hours. Nothing need be done or check f.o:r proper inftation after 28 hours. lnflation pressure checked daily for sever.al days aner installed.

A fully charged hydraulic accumulator provides?. Air pressure to various hydraulic compartments. A source for additional hydraulic power during high peak demand. Positive fluid flow to the pump inlet. Additional hydraulic fluid.

The hydraulic component that automatlcaily directs fluid from etitheir the normal source or an emergency source to an actuating cylinder is called a?. Shuttle valve. Time delay valve. Bypass valve. Crossf low valve.

In a vertical steady-state ascent, the helicopter has to overcome?. Thrust and lift vs. weight and drag. lift and weight vs. drag and thrust. Torque and thrust vs. lift and drag. Thrust and weight vs. lift and drag.

Which rotor head design has a inability to corred for dissymmetry in lift?. Semi-rigid. Semi-articutated. Fully-articulated. Rigid.

Wlich rotor head design uses individual flapping hinge fer each blade?. Rigid. Semi-articulated. Semi-rigid. Fully-articulated.

What force is imposed on a helicopter in forward steady state flight?. Dissymmetry of lift. Translational lift. Transitional lift. Gyroscopic precession.

At. what speed does effective translational lift take place?. 5-10 mph. 10-15 mph. 15-20 mph. 25-35 mph.

A European made helicopter in forward cruise requires?. Right pedal. Left pedal. Neutral pedal. Full right pedal.

A U.S. made helicopter during take-off requires what anti-torque input?. Right pedal. Left pedal. Neutral pedal. Negative pitch.

Wiat causes the tilt of the tip path plane of the main rotor?. Collective pitch. Flapping hinge. Translating tendency. Cyclic control.

Wlat type of bearings are used on control linkages?. Roller bearings. Needle bearings. Ball bearings. Spherical bearings.

Blade alignment is?. Necessary on fully-articulated heads. Spanwise balance. Chordwise balance. Not required on semi-articulated heads.

A main rotor is out of track the vibration is?. 1:1. 1:2. 1:3. Lateral.

A helicopter is in forward flight; the mast is under?. Torsional load. Radial and torsional load. Torsional and tension load. Tension.

What type of rotor is susceptible to mast bumping?. Rigid. Semi-articulated. Semi-rigid. Fully-articulated.

The drive link on a swashplate is connected to?. The cyclic. The mast. The counter weight fly bar. The mixer box.

A helicopter is overstable and control response is delayed; the problem is likely?. To hard stabilizer dampener. To soft stabilizer dampener. Out of rig rotor. Out of round rotor head.

On a helicopter having a free turbine engine, the twist grip is used to control what?. Throttte. Max. beep. Power turbine RPM. Compressor RPM.

Hydraulic pumps are of what type?. Gear. Piston. Gerotor. Vane.

What would happen if the freewheel unit seized during a autorotation?. The engine would drive the rotor. The rotor would drive the englne. The rotor would drive the transmíssion. Allow the engine to drive the transmission.

A helicopter transmisslon uses?. lts own lubricant. Engine oíl. An oil/fuel mixture. Hydraulic oil and back pressure from the engine.

Tail rotors may be dynamically balanced with the?. Chadwick-Helmuth2. Strobex. Vibrex. Phazor.

What type of airfoil is the horizontal stabilizer?. Symmetrical. lnverted dissymmetrical. lnverted Symmetrical. Unsymmetrical.

What does an inverter do?. Converts AC ta DC. Converts DC to AC. Changes field dírection. Maintains a constant AC voltage.

Conical elastomeric bearings used in a rotor head provide?. Movement about three axes and absorb heavy torsional loads. Absorption of high radial and axial loads wfth some movement in both directions. Absorptíon of low radial and axial loads with very little movement in any direction. Movement about two axes and absorb light torsional loads.

In a turbine powered helicopter. the rotor brake system operates on?. Engine oil. Transmission oil. Manual operation. lndependent hydraulic system.

Toe relationship betv.ieen blade alignment is necessary for the specific purpose of placing the blades C of G with?. The hub of the rotor. C of P. Chordwise balance. Toe longitudinal axis of the helicopter.

An Underslung rotor is utilized to counter?. Coriolis effect. Oissymmetry of lift. Gyroscopic precession. Cyclic drift.

\Mlat property puts the action at a different point on the swashplate?. Gyroscopic precession. Dissymmetry of lift. Collective pitch. The cyclic control.

In forward steady flight diectional change is affected by what?. Positive tail rotor input. Negative tail rotor input. Collective pitch change. Rotor disk tilt.