Fam 2 Connor Gouge Adv Helo
FAM 2 CONNOR GOUGE ADV HELO
familiarization flight 2
Discuss 2
A. Flight Control System 2
B. Jammed Flight Controls 6
C. Hot Start 6
D. Hung Start 7
E. Engine Fire on Start (No Procedure in NATOPS) 7
F. Emergency Shutdown 7
G. Post Shutdown Fire (Internal) 8
H. Dynamic Rollover 8
I. Blowback (Normal App / Transition to Forward Flight) 10
J. Crew Coordination (Decision Making) 11
Introduce 11
A. NATOPS Brief 11
B. Engine Start Procedure 11
C. Vertical Take off and Land 11
D. Turn on the Spot / Clearing Turn 11
E. Normal Approach 11
F. Transition To Forward Flight 11
G. Shutdown Procedure 11
Practice 11
A. Check Lists 11
B. Pre / Post Flight Inspections 11
C. Basic Air Work 11
D. Level Speed Change 11
E. Air Taxiing 11
F. Hovering 11
G. Course Rules 11
H. Crew Coordination 11
Proceedures for the Day 13
Emergency Procedures for the Day 17
Discuss
A. Flight Control System
The flight control system (Figure 2-17) is a positive mechanical type, actuated by conventional helicopter controls which, when moved, direct the helicopter in various modes of flight. The system includes the cyclic controls, used for fore-and-aft and lateral control; the collective pitch (main rotor) control levers, used for vertical movement; and directional control (rudder) pedals, used for heading control. The control system forces are reduced to near zero by hydraulic servo cylinders which are connected to the control system mechanical linkages. A force trim system connected to the cyclic and tail rotor controls contains electrically operated mechanical units. There is no force trim connected to the TH-57B tail rotor controls.
The flight control system consists of push-pull control tubes and bellcranks, actuated by conventional helicopter cyclic, collective, and rudder controls. The controls are routed beneath the pilot seats aft to the center of the helicopter and then up to the cabin roof through the control column, which also serves as a primary cabin structure. Access doors are located on the aft side of the control column, and removable seats are provided for control inspection and maintenance accessibility. Cyclic and collective controls are routed to the main rotor blades through the swashplate. The swashplate and support assembly encircle the mast directly above the transmission. The swashplate is mounted on the universal support (pivot sleeve and uniball), which permits it to be tilted in any direction. Movement of the cyclic control stick results in a corresponding tilt of the swashplate about the uniball, which tilts the rotor tippath plane. Movement of the collective pitch lever actuates the sleeve assembly, which raises or lowers the swashplate and transmits collective pitch changes to the main rotor blades. The cyclic controls are properly coordinated with the collective control by action in the mixing lever at the base of the control column. The directional control (rudder) linkages are routed through the tailboom to the tail rotor. Fixed-length control tubes and a minimum of adjustable tubes simplify rigging. All self-aligning bearings and rod ends are spherical Teflon bearings requiring no lubrication.
Collective Pitch Control Lever. Acting independently of the cyclic is the collective system (figure 5-16). The collective stick through mechanical linkage transmits pilot inputs to the main rotor blades increasing or decreasing blade pitch angle equally and in the same direction. The collective stick located to the left of the pilot is mounted to a jackshaft. Also located at the jackshaft mounting point is a friction adjuster. The friction adjuster allows the pilot to adjust the amount of force required to move the collective. Control inputs are transmitted through a lever assembly and control tube up through the control column to the hydraulic servo. From the servo, control tubes connect with the collective lever. Moving the collective stick upward will cause the collective lever to be pulled downward. A downward movement of the collective lever will raise the pivot sleeve and uniball assembly and thus raise the swashplate assembly as shown in figure 5-17.
As the swashplate rises, the pitch angle of both rotor blades is increased equally.
Raising the collective will increase the torque effect and the TH-57, like all helicopters, must have a system to counter torque.
Directional Control Pedals
The TH-57 uses a two-bladed semirigid flapping type tail rotor as an anti-torque device. As shown in figure 5-18, control of the tail rotor is accomplished by control pedals, push-pull tubes, bellcranks, and a pitch change mechanism.
The control pedals, located on the cockpit deck, transmit control inputs by push-pull tubes to the tail rotor. Located with the control pedals is a starwheel adjuster. Rotation of the starwheel adjuster will move the pedals equally closer or farther from the pilot's station. The control linkage, consisting of pushpull tubes, runs from the control pedals rearward up the control column through the tail boom to the pitch change mechanism. The pitch change mechanism mounted to the tail rotor gearbox consists of a lever, control tube, crosshead and pitch change links. The lever extends and retracts the control tube that runs through the tail rotor gearbox and drive shaft.
As the crosshead is attached to the control tube, the crosshead moves in and out. As shown in figure 5-18, the crosshead moving in and out will change the pitch angle of the tail rotor blades via the pitch change link and pitch horns. When left pedal is applied, control tubes are moved and the lever assembly retracts the control tube. As the control tube retracts, the crosshead moves closer to the yoke assembly; tail rotor blade pitch is increased.
Cyclic Pitch Control Stick. A cyclic control input will result in the rotor disc tilting and the aircraft moving in the direction of the control input. The cyclic stick, as depicted in figure 5-12, is mounted on the pivot support which allows the cyclic stick to move in a 360-degree direction (figure 5-12, items 1 & 5).
Also located at the base of the cyclic and part of the pivot support assembly is the friction adjuster. The friction adjuster allows the pilot to adjust the force required to move the cyclic stick. The pilot and copilot pivot supports are connected by a torque tube. The single yoke assembly transmits control inputs from the cyclic to the mixing lever. The mixing lever is located at the base of the control column. Fore-and-aft and lateral control inputs are intermixed by the mixing lever and transmitted up the control column to the hydraulic servos. Manual input is hydraulically boosted by the hydraulic servos and transmitted to the stationary swashplate by control tubes and bellcranks. The stationary swashplate takes control inputs from the cyclic and transmits them to the rotating controls. The rotating controls consist of the rotating swashplate, pitch change tubes and pitch change horns.
The swashplate assembly consists of a stationary swashplate, rotating swashplate, pivot sleeve (item 5), swashplate support, and a drive link (figure 5-13). The swashplate support is mounted to the top of the transmission and provides the mounting point for the pivot sleeve. The base of the pivot sleeve is the mounting point for the collective lever. The top of the pivot sleeve is of a uniball construction (figure 5-14).
The uniball is the mounting point for the stationary swashplate. The uniball is what allows the stationary swashplate to tilt in any direction. The rotating swashplate is mounted to the stationary swashplate by a set of bearings and bearing cap. Tilting the stationary swashplate will cause the rotating swashplate to tilt in the same direction. A drive link is spline mounted to the mast at one end and to the rotating swashplate at the other end.
The drive link lever and collar set will cause the rotating swashplate to rotate at the same speed as the rotor system. The rotating swashplate is connected to the rotor blade pitch horns by two pitch control tubes. Input from the cyclic stick will be transmitted to the pitch horns and cause a pitch angle change. Moving the cyclic stick forward will cause the stationary swashplate to tilt forward. The rotating swashplate will also tilt forward since it is mounted to the stationary swashplate as shown in figure 5-15.
A low point front and a high point rear is created when the swashplate is tilted forward. As the swashplate rotates, the pitch change tubes move up on the high side and down on the low side. As a pitch change tube moves upward, blade pitch angle increases, and as it moves downward, blade pitch angle decreases. The retreating blade climbs and the advancing blade descends.
Force Trim System. The system incorporates a magnetic brake and force gradient spring in the cyclic to provide artificial feel in the systems. Depressing the cyclic grip FORCE TRIM button will cause the trim damper units (Figure 2-17) to position the force gradient spring in a position corresponding to the position of the cyclic sticks. FORCE TRIM buttons are mounted on the pilot and copilot cyclic grip (Figure 2-18). A force trim on/off switch is located on the AFCS control panel (TH-57C) or on the pedestal (TH-57B).
B. Jammed Flight Controls
Aircraft experiencing a control malfunction during ground operations will be immediately inspected by qualified technicians prior to further flight operations or continued turnup / maintenance action. If jammed or restricted flight controls are experienced on the ground by a pilot or maintenance personnel, no attempt shall be made to free the controls. Light pressure shall be held against the restriction or jam while a thorough inspection of the flight control system is being conducted.
Pilots of aircraft that have just returned from a flight during which a control malfunction was experienced will request an immediate flight control system inspection.
C. Hot Start
INDICATIONS:
TOT exceeds limits.
TOT light illuminates.
Note
Any of the following indications, particularly when combined, indicates an increased potential for a hot start and may necessitate an aborted start to preclude an overtemp:
• Excessive rise in TOT.
• TOT accelerates through 8401.
• Battery voltage stabilized below 17 volts
on starter engagement.
PROCEDURES:
* 1. Twist grip - Close.
*2. Fuel valve -OFF.
*3. Starter - Secure After TOT Stabilizes at 4000C or Below.
*4. BAT switch -OFF.
CAUTION
Do not allow the TOT to rise above 810oC for more than 10 seconds or 927oC for any length of time.
Note
Utilize APU for subsequent start attempts after aborted starts if TOT limits have not been exceeded.
D. Hung Start
INDICATIONS:
Ng rises slowly and stabilizes below 50 percent.
TOT rises more slowly than normal.
PROCEDURES:
* 1. Twist grip - Close.
*2. FUEL VALVE - OFF.
*3. STARTER - Secure After TOT Stabilizes Below 400oC.
*4. BAT switch -OFF.
E. Engine Fire on Start (No Procedure in NATOPS)
INDICATIONS:
FIRE warning light
Smoke
Fire
Indication from fire guard
PROCEDURES:
* 1. Twist grip - Close.
*2. FUEL VALVE -OFF.
*3. BAT switch -OFF.
(C) *4. Rotor brake - Engage.
*5. Helicopter - EXIT and use the fire bottle to extinguish the fire or get clear of the aircraft.
WARNING
After exiting aircraft, beware of rotor blades.
F. Emergency Shutdown
Following any emergency that necessitates rapid crew egress, execute shutdown as follows:
* 1. Twist grip - Closed.
*2. Fuel valve -OFF.
*3. BAT switch -OFF.
(C) *4. Rotor brake - Engage.
G. Post Shutdown Fire (Internal)
A postshutdown fire is an internal engine fire that occurs in an engine that is stopped or coasting down.
INDICATIONS:
TOT rises above 400oC.
Flames or smoke coming from engine.
PROCEDURES:
* 1. Starter - Engage.
*2. Fuel valve -OFF.
*3. Igniter circuit breaker - Pull.
*4. Starter - Secure After Fire is Extinguished.
H. Dynamic Rollover
DYNAMIC ROLLOVER CHARACTERISTICS
Dynamic rollover is a phenomenon peculiar to helicopters and primarily to skid-configured / rigid gear helicopters. It is an accelerated roll about a ground attached point (i.e., landing gear or skid). This roll requires ground contact and occurs extremely rapidly in proportion to both roll rate and angle, allowing little opportunity for recovery.
During normal takeoffs and landings, slope takeoffs and landings, or landings and takeoffs with some bank angle or side drift, the bank angle or side drift can cause the helicopter to get into a situation where it is pivoting about a skid. When this happens, lateral cyclic control response is more sluggish and less effective than for the free hovering helicopter. Consequently, if the bank angle (the angle between the aircraft and the horizon) is allowed to build up past 15o, the helicopter will enter a rolling maneuver that cannot be corrected with full cyclic and the helicopter will roll over on its side. In addition, as the roll rate and acceleration of the rolling motion increases, the angle at which recovery is still possible is significantly reduced. The critical rollover angle is also reduced for a right skid-down condition, crosswinds, lateral center-of-gravity offset, and left rudder pedal inputs.
When performing maneuvers with one skid on the ground, care must be taken to keep the aircraft trimmed, especially laterally. For example, if a slow takeoff is attempted and the tail rotor thrust contribution to rolling moment is not trimmed out with cyclic, the critical recovery angle may be exceeded in less than 2 seconds. Control can be maintained if the pilot maintains trim, does not allow aircraft rates to become large, and keeps the bank angle from getting too large. The pilot must fly the aircraft into the air smoothly keeping executions in pitch, roll, and yaw low and not allowing any untrimmed moments.
Collective is much more effective in controlling the rolling motion than lateral cyclic because it reduces the main rotor thrust. A smooth, moderate collective reduction of less than approximately 40 percent (at a rate less than approximately full up to full down in 2 seconds) is adequate to stop the rolling motion with about 2o bank angle overshoot from where down collective is applied. Care must be taken to not dump collective at too high a rate as to cause fuselage-rotor blade contact. Additionally, if the helicopter is on a slope and the roll starts to the upslope side, reducing collective too fast creates a high rate in the opposite direction. When the low slope skid hits the ground, the dynamics of the motion can cause the aircraft to roll downslide and over on its side. Do not pull collective suddenly to get airborne as a large and abrupt rolling moment in the opposite direction will result. This moment may be uncontrollable.