MODEL АК1-3 HELICOPTER Master Data DATE OF ISSUE: 20 APRIL 2011 DB AEROCOPTER, Poltava, Ukraine
1. GENERAL АК1-3 Helicopter. Overall View Page 3
1.1. AK1-3 THREE VIEW АК1-3 Three View Principal Dimensions Page 4
Main rotor diameter 1.2. GENERAL DIMENSIONAL DATA Number of main rotor blades 3 6.84 m Main rotor disc area 36.74 m 2 Main rotor solidity ratio 0.0475 Blade airfoil NACA 63012 Blade planform Tail rotor diameter rectangular Number of tail rotor blades 2 1.29 m Tail rotor solidity ratio 0.114 Helicopter length, rotor blades turning Helicopter length, rotor blades at rest Helicopter width, main rotor blades at rest Helicopter height 8.096 m 5.675 m 1.35 m 2.27 m Horizontal stabilizer area 0.15 m 2 Vertical stabilizer area 0.267 m 2 Skid gear tread Fuselage-to-ground clearance 1.645 m 0.45 m Cabin doors Height 1.04 m Width 0.95 m Main rotor gearbox, including main rotor drive shaft Height Width 0.94 m 0.376 m Engine Height 0.7 m Width 0.5 m Fuel tank Capacity 72 liters Cockpit dimensions: Lenght Width Height 1.52 m 1.35 m 1.49 m Page 5
1.3. DESIGN FEATURES The АК1-3 is a standard single-rotor helicopter with a three-bladed main rotor system and two-bladed tail rotor. The helicopter power plant is the Subaru Model EJ25 reciprocating engine. A tubular welded open frame forms the main load-carrying structure for the helicopter. The center section of the welded frame provides attachments for and supports helicopter units and assemblies. The forward section of the frame holds the cabin. The cabin encloses the crew area and contains flight controls, an instrument panel and other airborne equipment. The instrument panel is located forward of the pilots seats. The upper instrument panel includes annunciator panel and a cluster of flight and navigation instruments. The center instrument panel includes a Fuel Level Indicator, Engine Coolant Temperature Indicator, Main Rotor Gearbox Oil Temperature Indicator, ENGINE power switch, master POWER switch, IDLER actuator power switch (rotor engagement/disengagement), radio set control panel, cabin ventilation and heating system control panel. The lower instrument panel includes a cluster of fuses and power switches for gyro horizon, instrument integral lighting and navigation lights, landing light, engine cooling system fans and main rotor rpm sensitive switch audio warning system (overspeed/underspeed). The cyclic control sticks and tail rotor pedals are located in front of the pilots seats. The collective pitch control sticks are located to the left of the pilots seats. The collective and cyclic control system is the mechanically linked push-pull control linkage. The tail rotor control system is a combination push-pull/cable control linkage. The cabin floor section is a load-carrying structure. It supports pilots seats, main and tail rotor control system components, instrument panel, cabin ventilation and heating system. The seats are nonadjustable. The seats are provided with seat belts and shoulder harnesses ensuring security of the crew belting. The canopy and door transparent areas are of cast acrylic material and give a good forward view. The backward view of the engine and tail boom is provided by the view windows in the rear of the cabin. The tail boom is a cylindrical riveted structure of sheet duralumin. It attaches to the center section of the helicopter frame. The tail boom houses the tail rotor drive shaft and cable control linkage of the tail rotor control system. At the aft end, the tail boom supports the tail rotor gearbox, horizontal and vertical stabilizers and a tail skid. The tail boom is provided with four access doors for inspection of main assemblies of the tail rotor drive shaft and attachment bracket for the tail boom supporting struts. The landing gear is the skid type. The skid tubes attach to fittings at the lower ends of transverse springy shock struts and carry brackets for installation of ground handling wheels. To ease pilots entry to the cabin, each fore strut is fitted with an entry step. Page 6
The power plant is the Subaru Model EJ25 four-cylinder, horizontally opposed, four-stroke, liquid-cooled reciprocating engine. Engine displacement is 2500 cm 3 and it is rated at 156 hp (115 kw). The engine has a 16-valve operating mechanism and two camshafts, one per cylinder head. The main rotor gearbox mounts on the center section of the helicopter frame structure. It is lubricated by a self-contained lubrication system and is cooled by airflow around the housing. Oil level is checked in a sight gage window. The main rotor gearbox is equipped with an oil temperature sensor driving the M/R Gearbox Oil Temperature Indicator furnished on the center instrument panel. The engine transmits power through a belt drive transmission assembly to the main rotor gearbox and tail rotor drive shaft. The upper pulley of the belt drive transmission incorporates an overrunning clutch that permits the main rotor to drive during the autorotation without engine power. Tensioning of drive belts is accomplished by the pilot-controlled idler pulley. The helicopter has a three-bladed main rotor system. The main rotor hub provides a torsionally-soft attachment of blades through a set of thin torsion plates of high-strength steel. The tail rotor drive shaft is a duralumin tube with plate couplings at the ends. The shaft rides in three bearing supports mounted to the tail boom frames. Excessive oscillation of the drive shaft during acceleration and deceleration of the rotor system is suppressed by two plate couplings and rubber dampers provided at the shaft bearing supports. The tail rotor gearbox is located at the aft end of the tail boom and has a self-contained lubrication system. The tail rotor is mounted on the output shaft of the tail rotor gearbox through a universal joint. The tail rotor control system mounts on the tail rotor gearbox output shaft. The helicopter fuel tank has a capacity of 72 liters. It is located in the center section of the helicopter frame on the engine mount aft of the cabin. Tank fueling is through a filler neck. Fuel quantity in the tank is monitored by a fuel level transmitter driving the Fuel Level Indicator furnished on the center instrument panel. Page 7
2. LIMITATIONS 2.1. HELICOPTER CAPABILITIES Typical uses of the АК1-3 lightweight helicopter include the following: - pilot training; - patrol missions (surveillance of production facilities, oil and gas pipelines, electric power lines, highways, forest fires, etc.); - agricultural land treatment (set with spray system); - aerial sports; - commercial capabilities (transportation of one passenger). 2.2. MINIMUM CREW The minimum crew for the АК1-3 helicopter is one pilot (captain) if the mission permits. Solo flights are permitted both from the left and right seats. 2.3. MAXIMUM OCCUPANCY The maximum crew is two occupants: - for pilot training: a pilot trainee and a flight instructor; - for patrol missions: captain in the left seat and an observer or optional equipment operator in the right seat; - in particular cases, apart from the captain, the crew may include a co-pilot or a navigator or an aircraft mechanic or an aircraft technician. 2.4. GENERAL OPERATING LIMITATIONS 2.4.1. Flight operations of the АК1-3 helicopter are limited to day flights under VFR conditions, cloud ceiling being 150 meters and horizontal visibility being 2,000 meters minimum. 2.4.2. Flight in icing conditions is prohibited. 2.4.3. The maximum operating altitude is 3,000 meters, ISA. 2.4.4. The maximum aerodrome elevation is 1,200 meters, ISA. 2.4.5. The AK1-3 sea-level operating temperature range is from -18 ºC to +35 ºС. For operation at Н=3000 m, outside air temperature shall not be below -25 ºС. For altitude/outside air temperature envelope see Fig. 2. Page 9
Нpress, m ISA t, C Fig. 2. Altitude/outside air temperature envelope 2.5.1. CG Limitations - Forward CG limit: +80 ; - Aft CG limit: -45 mm; 2.5. FLIGHT LIMITATIONS 2.5.2. Takeoff and Landing Weight Limitations - The Maximum Gross Weight is 650 kg. 2.5.3. Rotor Speed Limitations - The maximum rotor speed limitation is 565 rpm; - The recommended rotor speed range is 535 to 555 rpm; - The minimum rotor speed limitation is 505 rpm. 2.5.4. Maximum VNE is 180 km/h. 2.5.5. When changing the direction of hovering turn, never make full reversal of tail rotor pedals within less than three seconds. 2.5.6. At sea level do not perform 360-degree turns at wind velocities in excess of 8 m/s. At wind velocities of 8 to 10 m/s, limit hovering turns to 90º relative to the wind direction. At wind velocities in excess of 10 m/s, hover only upwind. 2.2.7. NEVER: - perform more than 20-degree banked turns at 0 to 40 km/h airspeeds; Page 10
- perform more than 10-degree banked steady sideslipping at airspeeds above 100 km/h and more than 5-degree banked sideslipping at airspeeds of up to 100 km/h. 2.5.8. Do not engage and disengage main rotor, hover, take off and land if wind velocity is out of Table 2.1 limitations. Wind Direction Headwind Crosswind: from the left from the right Tailwind Table 2.1 Wind Velocity Limits (m/s) For rotor engagement For takeoff, hovering, and disengagement maneuvers, landing 15 15 8 8 5 2.5.9. For power-on gliding speed limitations for all weights refer to Table 2.2. Table 2.2 Power-On Gliding Speed Limits (km/h) Flight Altitude, m Maximum Minimum 10 8 5 3,000 1,000 1,000-500 500-0 120 160 180 100 80 60 2.3. For autorotation gliding speed limitations for all weights refer to Table Flight Altitude, m Table 2.3 Autorotation Gliding Speed Limits (km/h) Maximum Minimum 3,000 1,000 1,000-0 110 130 100 80 15º. 2.5.10. Do not perform autorotation turns with a bank of more than 2.5.11. For rugged terrain, the minimum operating altitude is 20 meters and the minimum operating speed is 60 km/h. 2.5.12. The minimum operating altitude by day over plain ground is 20 meters. 2.5.13. Avoid hovering at altitudes of 10 to 125 meters if there is no special need for it. Page 11
2.5.14. The maximum rate of hovering turn is 45 deg/s. 2.5.15 Rotor RPM and Time Limitations: - rotor maximum autorotation speed (with engine at idle) is 565 rpm, during which rotor overspeed of up to 575 rpm is permitted for five seconds maximum; - rotor maximum speed throughout engine power settings above idle is 565 rpm for 60 seconds maximum. 2.5.16. Rotor minimum speed (rpm drop) in flight during conversions is 490 rpm. WARNING: To avert a drop in rotor rpm during changes in helicopter attitude for engine acceleration, the rate for adding collective pitch must be no less than three seconds. To avert rotor overspeed, do not reduce collective pitch at a rate of more than 1 deg/s. During conversions, NEVER use rapid lowering of collective pitch along with rapid forward aft reversal of cyclic stick as it may result in damage to rotor blades and tail boom. 2.5.17. Recommended Flight Profile Figure 2.1. Height Velocity Diagram at Sea Level Page 12
2.6. POWER PLANT AND ROTOR DRIVE SYSTEM LIMITATIONS 2.6.1. Power Plant Limitations Table 2.5. Engine Coolant Temperature Limitations Engine Power Throughout power settings Coolant Temperature, ºС Minimum Recommended Maximum 60 70-90 100 Engine Power Table 2.6. Engine RPM Limitations Engine RPM Minimum Recommended Maximum Idle 1000-1500 Above idle 5000 5200-5500 5600 (for 60 s maximum) 2.6.2. Rotor Drive System Limitations Table 2.7 Parameter Main Rotor Gearbox Tail Rotor Gearbox Minimum oil temperature for rotor -40-40 engagement, ºC Recommended oil temperature for continuous operation, +70 +70 ºC Maximum oil temperature, ºC +110 +110 Page 13
2.7. AIRWORTHINESS LIMITATIONS 2.7.1 AK1-3 Helicopter life times Specified life First overhaul period Overhaul period Warranty period 8000 Hours 2000 Hours 2000 Hours 100 Hours or 1 year Life-limited parts No Part name Model Service life Overhaul Specified 1 Main gearbox ГР-4 1000 H 4000 H 2 Clutch mechanism ПМ-4-4000 H 3 Actuator МП-100МД 2000 H 8000 H 4 Swash plate АП-5 2000 H 4000 H 5 Main rotor hub ВНВ-6 1000 H 4000 H 6 Main rotor blade ЛНВ-7-2000 H 7 Tail rotor hub ВРВ-8-2000 H 8 Tail gearbox ХР-9-4000 H 9 Tail shaft ВТ - 2000 H 10 Tail boom БХ-10 2000 H 4000 H 11 Supporting strut П-10-4000 H 12 Horizontal stabilizer С-10-4000 H 13 Upper vertical stabilizer КВ-10-4000 H 14 Lower vertical stabilizer КН-10-4000 H 15 Tail rotor blade ЛРВ-11-2000 H 16 Fuel pump ТН - 2000 H 17 Radiator ВЖР-1-4000 H 18 Radiator ВЖР-2-4000 H 19 Cooler ВЭ-1-2000 H 20 Muffler Г-1-500 H 21 Exhaust manifold ВК-1-500 H Page 14
2.7.2 DB Aerocopter s embodied and adapted EJ25 Engine life times Specified life First overhaul period 2000 Hours 1000 Hours Engine life-limited parts No Part name Part number Service life Overhaul Specified 1 Alternator ГН-90 1000 H 2000 H 2 Starter M000T30471-2000 H Page 15
3. PERFORMANCE DATA 3.1. Hover and Vertical Climb Performance Rotor maximum thrust at hover determines aircraft gross weight and vertical climb performance. The maximum rotor thrust is developed at hover in ground effect. The ground effect ceases to influence rotor thrust at hover heights exceeding rotor disc diameter. For the ground effect impact on rotor thrust at takeoff and hover refer to chart in Figure 3.1 presenting the AK1-3 rotor thrust performance ( hover and takeoff engine power. T h / T ) variation for skid height skid For hover ceiling versus gross weight and outside air temperature see Fig. 3.2. h at Fig. 3.1Rotor Thrust for Hover Height Curve Page 17
Fig. 3.2 Hover Ceiling Out of Ground Effect Versus Gross Weight 3.2. For AK1-3 level flight performance for Gross Weight up to and above 550 kgf refer to Table 3.1. Nos. Airspeed Table 3.1 Gross Weight, kgf up to 550 above 550 1. Minimum cruise speed 50 km/h 50 km/h 2. High-endurance cruise speed 85 km/h 80 km/h 3. Best range cruise speed 120 km/h 120 km/h 4. Maximum cruise speed, up to 1,000 m 165 km/h 160 km/h 5. Never exceed speed (VNE), sea level 180 km/h 180 km/h Page 18
3.3. Climb Performance For rate of climb for altitude performance see Figure 3.3 Fig. 3.3 Rate of Climb Chart 3.4. Autorotation Descent Performance The autorotation descent performance is subject to gliding angle ( glide ) and rate of descent (Vy) which in turn depend on gliding speed and rotor rpm. For best range gliding speed and angle data see Table 3.2. Table 3.2 Nos. Item Cross Weight, kgf up to 550 above 550 1. Minimum gliding angle 11.4º 13.8º 2. Gliding speed: - up to 1,000 m - above 1,000 m 115 km/h 120 km/h 120 km/h 125 km/h NOTE. For autorotation gliding range calculation for a given altitude and airspeed of 115 to 125 km/h, it may be considered that every 300 meters of altitude ensure gliding range of 1,000 meters, e.g., maximum gliding range from a 900-meter altitude will be 3,000 meters. Page 19
For minimum rate of descent autorotation gliding speed data see Table 3.3. Table 3.3 Nos. Item Gross Weight, kgf up to 550 above 550 1. Rate of descent 9.5 m/s 9 m/s 2. Autorotation gliding speed 90 km/h 95 km/h NOTE. The autorotation gliding angle and rate of descent data specified in Tables 3.2 and 3.3 apply under standard atmosphere conditions. 3.5. Aircraft Longitudinal Trim For in-trim rotor collective pitch for level flight airspeed chart see Figure 3.4. Fig. 3.4 Rotor Collective Pitch Versus Indicated Airspeed Curve Page 20
4. POWER PLANT The power plant is designed to drive the main and tail rotor systems and power units and assemblies of the helicopter systems. The helicopter power plant is the SUBARU Model EJ25 four-cylinder, horizontally opposed, liquid-cooled reciprocating gasoline engine with a 16-valve operating mechanism. Weight Main Data Cylinder diameter and piston stroke 110 kg 99.5 79.0 mm Displacement 2,457 cm 3 Compression pressure 9.6 to 12.4 kg/cm 2 Permissible compression pressure difference 0.5 kg/cm 2 Power rating Maximum crankshaft speed Operational speed Idling speed 156 hp (115 kw) 5600 rpm Firing order 1-3-2-4 5200 to 5500 rpm 1000 to 1500 rpm Approved fuel unleaded auto gasoline of laboratory octane number 95 minimum. The recommended fuel grade is А-95 (ДСТУ 4063-2001) Approved oil Approved coolant Oil system servicing Cooling system servicing Fuel consumption Oil consumption universal motor oil for gasoline engines class SL (API) minimum and 5W-50 (SAE) viscosity ethylene glycol based antifreeze solution grade А40М 4.2 to 4.5 liters 10 liters 24 to 32 l/h 0 to 0.5 l/h Page 21
5. MAINTENANCE 5.1 For continued airworthiness, the helicopter operation and maintenance must be in conformity with all airworthiness requirements. Helicopter maintenance includes organization and accomplishment of scheduled maintenance procedures, troubleshooting, Service Bulletin changes, replacement of helicopter units and assemblies. 5.2 The maintenance schedule provides for the following kinds of maintenance: - line maintenance; - scheduled maintenance; - maintenance in store; - seasonal maintenance; - special-purpose maintenance. 5.2.1 Line maintenance includes: а) preflight maintenance; b) turn-round maintenance; c) post-flight maintenance. The pre-flight maintenance shall be performed immediately before the flight in accordance with the flight missions of the day. The turn-round maintenance shall be performed before each next flight during preflight time in accordance with the flight mission. The post-flight maintenance shall be performed at the end of each flying day. 5.2.2 Scheduled maintenance is performed at certain intervals by the helicopter operating time (engine hours registered by the Engine Hourmeter are taken to be helicopter operating time). The frequency of scheduled maintenance checks is multiple of 50±5 operating hours. Nos. Checks Hours 50±5 100±10 500±50 1 2 3 4 5 4.1. Preparatory Procedures 4.1.1. Preparation of ground-support equipment, maintenance tools and facilities + + + 4.1.2. Cleaning helicopter + + + 4.1.3. Preparation of helicopter for maintenance + + + 4.2. Inspection and Maintenance Procedures Airframe and Power Plant 4.2.1. Cabin inspection + + + 4.2.2. Frame inspection + + + 4.2.3. Landing gear inspection + + + 4.2.4. Inspection of tail boom and supporting struts + + + Page 22
Nos. Checks Hours 50±5 100±10 500±50 1 2 3 4 5 4.2.5. Inspection of tail rotor blades + + + 4.2.6. Inspection of tail rotor hub + + + 4.2.7. Inspection of tail rotor gearbox + + + 4.2.8. Greasing tail rotor gearbox shaft + 4.2.9. Changing tail rotor gearbox oil + + 4.2.10. Inspection of stabilizers + + + 4.2.11. Tail skid inspection + + + 4.2.12. Inspection of tail rotor drive shaft + + + 4.2.13. Inspection of main rotor blades + + + 4.2.14. Inspection of main rotor hub + + + 4.2.15. Greasing main rotor blade droop stops + 4.2.16. Inspection of swashplate assembly + + + 4.2.17. Inspection of main rotor gearbox + + + 4.2.18. Inspection of magnetic plug + + + 4.2.19. Changing main rotor gearbox oil + + 4.2.20. Greasing main rotor gearbox shaft + 4.2.21. Inspection of belt drive transmission assembly + + + 4.2.22. Verification of drive belts tension + + + 4.2.23. Inspection of idler pulley and spring damper + + + 4.2.24. Inspection of МП-100 actuator + + + 4.2.25. Inspection of control linkage + + + 4.2.26. Checking flight controls for freedom of movement + + + 4.2.27. Control linkage tension check + + 4.2.28. Engine inspection + + + 4.2.29. Inspection of exhaust system + + + 4.2.30. Changing engine oil and replacement of oil filter + + + 4.2.31. Replacement of engine fuel filter + + 4.2.32. Inspection of air throttle control linkage + + + 4.2.33. Replacement of air filter of the crankcase ventilation system + + + 4.2.33a. Replacement of intake air filter + + 4.2.34. Replacement of generator driving belt + 4.2.35. Replacement of spark plugs + + 4.2.36. Replacement of pulleys and timing belt of the valve operating mechanism + 4.2.37. Verification of cylinder compression pressure + + 4.2.38. Verification of valve clearance + + Page 23
Nos. Checks Hours 50±5 100±10 500±50 1 2 3 4 5 4.2.39. Engine ground check + + + 4.2.40. Fuel system inspection + + + 4.2.41. Inspection of engine cooling system and cabin ventilation and heating system 4.2.42. Changing engine coolant 4.2.43. Inspection of Engine valve operating mechanism drive Communications Equipment + + + + (24 months) + + 4.2.44. Inspection of communications equipment + + + 4.2.45. Operational test of communications equipment + + + Aircraft Equipment 4.2.46. Inspection of electrical equipment + + + 4.2.47. Inspection of high-voltage cables for condition + + + 4.2.48. Operational test of electrical equipment + + + 4.2.49. Inspection of aircraft instruments + + + 4.2.50. Operational test of aircraft instruments + + + 4.3. Closing Procedures 4.3.1. Maintenance closing procedures + + + 4.3.2. Covering helicopter + + + 4.3.3. Completing maintenance documentation + + + 5.2.3 Maintenance in store varies with storage time and includes preparation for storage and in-store maintenance procedures. 5.2.4 Seasonal maintenance consists in preparation of the helicopter for seasonal (autumn-winter, spring-summer) operation. 5.2.5 Special-purpose maintenance must be performed after a rough landing, a bumpy-air flight and for helicopter transportation. Page 24