The General Electric T-700/T-701C CW2 Rauch References: -10 T700 Engine manual Student Handouts UH-60L Qualification book.
Download ReportTranscript The General Electric T-700/T-701C CW2 Rauch References: -10 T700 Engine manual Student Handouts UH-60L Qualification book.
The General Electric T-700/T-701C CW2 Rauch References: -10 T700 Engine manual Student Handouts UH-60L Qualification book OBJECTIVE Develop pilots understanding of the T700 and T701C engines. Topics •Engine characteristics •History •Electrical control unit (ECU/DEC) •Hydromechanical unit (HMU) •Pressure and overspeed unit (POU/ODV) •NP overspeed protection •Engine Alternator ENGINE CHARACTERISTICS • Output power: 1,543 A/1,662 L SHP (sea level standard day) • Type of compressor: 5 axial stages, 1 centrifugal • Variable geometry: IGV+ stage 1&2 stator vanes • Engine weight: 415 A/ 456 L LBS • Time between overhaul: none(on condition) HISTORY&DEVELOPMENT •The T700 engine design was directed to minimizing required maintenance, T701C was derived from T700 w/85% common parts w/improvements to increase of 20% of Max power •Both maintenance tasks have been simplified •Corrective maintenance is on a “on condition” basis •Modular design allows sub-system replacement HISTORY CONTINUED: • • • • • • Lock wire elimination Tool requirements reduced LRU’s External lines reduced HMU no Rigging Dual sided sight glass and “impending” bypass indicators ENGINE MODULES • • • • Cold section Hot section Power turbine module Accessory module COLD SECTION COLD SECTION • Includes the inlet comprised of , swirl frame, main frame, front frame, and scroll case. These together with the inlet duct and blower make up the Inlet. • Compressor section, diffuser and midframe. • Hot air and oil provide anti-icing • Scroll vanes act as air/oil cooler supplementing the fuel/oil cooler BASIC OPERATION HOT SECTION • Consists of combustion liner, #1 stage nozzle assembly, and the gas generator turbines. • Gas generator turbines rotor drives the compressor • 12 fuel injectors, 2 primer nozzles, and 2 igniters POWER TURBINE MODULE • Comprised of the power turbine rotors, power turbine driveshaft, power turbine case, the #3 and #4 nozzles, and the exhaust frame. • Expanding exhaust gases exiting drives the free power turbine at 20,900 RPM=100%NP • Casing support the 7 TGT Thermocouples and the NP/torque sensors ACCESSORY MODULE • Mounts to the cold section module and is driven off the compressor section by a PTO via a radial driveshaft. • Provides drive and mounts (pads) for engine components ECU/DEC ECU/DEC….. WHAT’S IT DO? • Trims the HMU NG governor through the tq motor within acceptable engine limits to maintain isochronous NP governing. This can be overridden ONLY by TGT limiting. • Exchanges tq signals to provide automatic load sharing for multi-engine use. • Provides signal to the POU/ODV for NP overspeed protection 106+- 1% • Provides cockpit signals, NP, TGT, TQ ECU FUNCTIONS, OR CHECK RIDE ANSWERS ? • Np reference from cockpit • Overspeed signal to POU (redundant power,TQ SIGNAL) • TGT limiting, 837-849 • Signals to cockpit, TQ, TGT, Np • History recorder signal • Isochronous NP governing(will maintain ref.) • Torque load sharing HYDOMECHANICAL UNIT HMU DESCRIPTION • Mounted on the aft center of the AGB • Receives filtered fuel through cored passages in the AGB • High pressure vane type pump. Max 832 PSI HMU FUNCTIONS • • • • • • • • • Pumps Fuel Meters Fuel Collective pitch compensation (LDS) Acceleration/deceleration flow limiting Ng limiting (Governing & shutdown) Variable geometry positioning ECU/DEC Lockout/PAS override (lockout) Torque motor to trim NG governor Open Vapor vent (priming) POU/ODV POU/ODV DESCRIPTION • The Pressurizing overspeed unit and Overspeed drain valve is mounted on the rear of the accessory section of the engine • 3 outlets. Start fuel manifold, main fuel manifold, and overboard drain or overspeed solenoid valve for T701C (+bypass during overspeed) POU/ODV FUNCTIONS • • • Sequences fuel to start fuel manifold (2) No start fuel manifold or primer on T701C Sequences fuel to main fuel manifold (12) Purges start fuel manifold and nozzles after start, and main fuel manifold and nozzles during shutdown • Provides NP overspeed protection when activated from the ECU overspeed circuit - Hot start preventer-recycles all fuel back to the HMU inlet, shutting off fuel flow to the engine ENGINE ALTERNATOR ALTERNATOR DESCRIPTION • Mounted on the right hand forward side of the Accessory gear box • Provides power to all essential engine functions • output consists of 3 individual signals (windings) • May fail independently or as a unit ALTERNATOR FUNCTIONS (BY WINDING) • • • • Provides power to the ignition exciter Provides power to the ECU/DEC Provides power to history recorder/counter Provides NG signal to the cockpit NICE TO KNOW STUFF • • • • BLUE=OVERSPEED GREEN=COCKPIT SIGNALS BLACK=ENGINE IGNITION YELLOW=ENGINE ELECTRICAL FUNCTIONS ENGINE EP’S Increasing % RPM R • 1. ENG POWER CONT lever - Retard high power/TGT engine, maintain TRQ approximately 10% below other engine. • 2. LAND AS SOON AS PRACTICABLE. • If the affected engine does not respond to ENG POWER lever movement in the range between FLY and IDLE, the HMU may be malfunctioning internally. Continued • If this occurs: • 3. Establish single engine airspeed. • 4. Perform EMER ENG SHUTDOWN (affected engine). • 5. Refer to single engine failure emergency procedure. FLUCUATIONS/OSCILLATIONS %RPM Increasing/Decreasing (Oscillation). • 1. Slowly retard the ENG POWER CONT lever on the suspected engine. • If the oscillation stops: • 2. Place the engine in LOCKOUT and manually control the power. • 3. LAND AS SOON AS PRACTICABLE. • If the oscillation continues: • 4. Place the ENG POWER CONT lever back to FLY and retard the ENG POWER CONT lever of the other engine. Continued • When the oscillation stops: • 5. Place engine in LOCKOUT, manually control the power. • 6. LAND AS SOON AS PRACTICABLE. 615 794 Engine Alternator Failure (Is not in Emergency Procedures) (Rotor Stable) - Power control level on high TGT Engine, Retard to control TGT. Single-Engine Failure • • • • • • • 1. Collective-Adjust to maintain RPM R. 2._External cargo/stores - Jettison (if required). If continued flight is not possible: 3. LAND AS SOON AS POSSIBLE If continued flight is possible: 4. Establish single-engine airspeed. 5. LAND AS SOON AS PRACTICABLE MOST RELIABLE INDICATION OF ENGINE POWER ----------TGT Decreasing % RPMR • 1. Collective-Adjust to control RPM R. • 2. ENG POWER CONT lever-LOCKOUT low power/TGT engine. Maintain TRQ approximately 10% below other engine. • 3. LAND AS SOON AS PRACTICABLE. LOCKOUT OPNS -----ENGINE RESPONSE IS FASTER, TGT LIMITING INOP Torque Split Between Engines 1 and 2 • 1. If TGT of one engine exceeds the limiter, retard ENG POWER CONT lever on that engine to reduce TGT. Retard the ENG POWER CONT lever to maintain torque of the manually controlled engine at approximately 10% below the other engine. Continued • 2. If TGT limit on either engine is not exceeded, slowly retard ENG POWER CONT lever on high % TRQ engine and observe % TRQ of low power engine. • 3. If % TRQ of low power engine increases, ENG POWER CONT lever on high power engine -Retard to maintain % TRQ approximately 10% below other engine (The high power engine has been identified as a high side failure). CONTINUED • 4. If % TRQ of low power engine does not increase, or % RPM R decreases, ENG POWER CONT lever - Return high power engine to FLY (The low power engine has been identified as a low side failure). • 5. If additional power is required, low power ENG POWER CONT lever, momentarily move to LOCKOUT and adjust to set % TRQ approximately 10% below the other engine. •6. LAND AS SOON AS PRACTICABLE. NOTICEABLE BANGS , POPPING, POSSIBLE YAW (Fluctuations) Engine Compressor Stall • 1. Collective - reduce. • If condition persists: • 2. ENG POWER CONT lever (affected engine) Retard (TGT should decrease). • 3. ENG POWER CONT lever (affected engine) - FLY. • If stall condition recurs: • 4. EMER ENG SHUTDOWN (affected engine). • 5. Refer to single-engine failure emergency procedure. Engine High-Speed Shaft Failure • 1. Collective - Adjust. • 2. EMER ENG SHUTDOWN (affected engine). Do not attempt to restart. • 3. Refer to single-engine failure emergency procedure. LIMITS A • • • • • OIL TEMP OIL PRESS NG NP TGT -50-135/135-150 20-100/35-100 0-99/99-102/102-105 91-95/95-101/101-105/105-107 0-775/775-850/850-886 LIMITS L • OIL PRESS 22min/22-26/26-100/100-120 5min/120 0-810/810-851/851 start abort/851-878/ • TGT 878-903/903-949 SUMMARY • The T700 and T701C is closely integrated with helicopter components to provide proper power output for each flight condition • The system functions automatically, with no pilot action required after starting • Engine control is functionally split between the HMU and ECU/DEC. The HMU provides functions for safe operation, and the ECU/DEC performs a fine trim to reduce pilot workload • The system is self contained and engine powered QUESTIONS ?