1、ADS - 5 O -PRF AERONAUTICAL DESIGN STANDARD ROTORCRAFT PROPULSION PERFORMANCE AND QUALIFICATION REQUIREMENTS AND GUIDELINES 15 APRIL 1996 UNITED STATES ARMY AVIATION AND TROOP COMMAND ST.LOUIS, MISSOURI AVIATION RESEARCH AND DEVELOPMENT CENTER DIRECTORATE FOR ENGINEERING DISTRIBUTION STATEMENT A. di
2、stribution is unlimited. Approved for public release, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-AERONAUTICAL DESIGN STANDARD ROTORCRAFT PROPULSION PERFORMANCE AND QUALIFICAATION REQUIREMENTS AND GUIDELINES 24 APRIL 1996 - UNITED STATES ARMY AVI
3、ATION AND TROOP COMMAND ST.LOUIS, MISSOURI AVIATION RESEARCH AND DEVELOPMENT CENTER DIRECTORATE FOR ENGINEERING Chief, Propulsion Inteqration Branch _. VERNON R. EDWARDS Chiei, Propulsion Technology Division APPROVED BY: / and drains should discharge clear of the air vehicle structure. A drainage co
4、llection system to prevent fuel, oil, or hydraulic fluids from discharging on the ground or for use during shipboard operations should be provided. The compatibility guidelines for shipboard operations are specified in SD- 24L. The drainage collection system should- consist,of a -container, electric
5、ally actuated discharge valve, and appropriate plumbing and wiring. The drainage fluid collection system should be used to collect the fluids discharged from the engines, APU, and hydraulic pumps during normal or ship deck operations. -The collected fluids should be manually emptied from the contain
6、er via an electrically actuated discharge valve. Pressure differentials on all drains should not adversely affect engine or APU perf ormance. 2-3.1.3 Coolins. The engine and APU cooling systems should maintain the temperatures of all the equipment in the compartments and all the components on the en
7、gines/APU within their maximum allowable temperature limits for all engine/APU power levels at all ground and flight conditions, including idle power and soak-back after shut-down. The maximum allowable temperature limits should be those established in the engine model specification. If the engine u
8、tilizes an air-oil heat exchanger, the cooling flow through the exchanger should be consistent with the exchanger losses and oil temperature limits of the model specification. The airflow requirements for cooling should include consideration of engine seal leakage, engine flange leakage, compressor
9、vent flows, breather flows, engine-mounted oil tank and oil sump heat rejection, accessory drives, and all other sources of heat from power plant operation. 2-3.1.4 An engine and APU washing capability should be provided through appropriate plumbing lines and connections at easily accessible point(s
10、). Easily accessible point are those which do not require the removal of aircraft panels. This installation should provide for the attachment of a hose from a ground based pressurized liquid container to the on-board connection. A means to motor each engine without ignition should be provided. 2-3.1
11、.5 Mounts. Engine/APU mounts should be detachable, accessible, provide provision for engine/drive train alignment, and offer no interference to engine/APU or associated accessory installations. Engine mounts should react axial, vertical, lateral, and torsional loads as required.=The mounts should ac
12、commodate maximum flight maneuver and landing loads without failure or any permanent deformation. mount struts should provide mounting redundancy such that the engine will be held securely in place in the event of loss of any of the struts. The engine mounts should allow for engine thermal growth an
13、d should provide alignment of the engine with the transmission input module at all times. The mounts should provide engine retention when the engine is subjected to the maximum crash load factors (single axis and combined axis) or sudden engine seizure. structural deflections of the airframe from im
14、posing loads upon the engine. The primary The mounting system should prevent 2-3.1.5.1 Vibration. The engine/APU mounting system must limit the vibrations induced by the airframe rotor combination (including the tail rotor) at critical engine frequencies to levels acceptable to the engine. It must a
15、lso limit the resonant 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-structural vibration induced by the engine to levels which the airframe structure is designed to accommodate. 2-3.1.6 Access, The aircraft cowlings which close the engine/APU co
16、mpartments should provide access by removal or by hinging outward. The resulting access should be adequate for engine installation, servicing, maintenance, and removal. The access doors, when open, may double as work platforms to provide easier servicing for the engines and APU. The cowling design s
17、hould provide positive.locking sections such that vibrations and/or deflections should not result in opening or loss overboard during ground or flight operation. In.the closed position, the cowling sections should be sealed against the airframe and each other to minimize leakage of the compartment c
18、ooling airflow. 2-3.1.7 -ne Bleeds. Vents and J,eam . The high pressure, high temperature airflow exiting the engine constitute heat sources which must be accommodated and accounted for. It may be necessary to duct or diffuse the vent and leakage flows to minimize the potential adverse effects-ncomp
19、artnie-cooing and to prevent impingement on temperature-limited components such as wire bundles, electrical switches, fuel lines, etc. When the engine utilizes bleeds or vents for design, performance or stability purposes(such as seals, acceleration bleeds etc.), the back pressure restrictions estab
20、lished by the engine manufacturer must be observed and accommodated in the installation design. Tanks and lines within the engine 2-3.1.8 Survivability/Vulnerabilitv. compartment which contain flammable fluids should be located such that any leakage will not flow down upon the engine nor into the en
21、gine inlet airstream. In multi- engine aircraft when the engine compartments are adjacent to one another, special efforts are essential to maximize isolation and prevent communication between the compartments. Combustible fluid shut-off valves must be located outside the firewalls to insure their fu
22、nctionality in the event of a fire. 2-3.2 Air Induction System 2-3.2.1 mets, The air induction subsystem should prevent any erratic or adverse airflow distribution at all operating conditions and attitudes. The air induction subsystem should have minimal aerodynamic losses. A 0.5-1.0% pressure loss
23、should be attainable. acceptable engine inlet distortion limits as prescribed by the engine specification. The local total pressure should not differ from the average by more than 5.0%. In addition to acceptable inlet pressure distortion characteristics, the inlet flow at the engine face should not
24、result in local swirl that exceeds the swirl limits of the engine specification. The inlet location should minimize the potential for ingestion of foreign objects, armament parts and/or fragments, or exhaust gases. Engines should be protected from sand/dust, debris, or other foreign objects by the e
25、ngine IPS. All air induction inlets should be protected/sealed during aircraft nonuse. ducts should be free of traps/pockets and configured to prevent accumulation of vapor, fluids, or other contamination. The air induction system should not exceed the maximum Inlets and 2-3.2.2 Attachmeat and Loa-
26、. If the engine is directly.connected to the inlet duct, the aircraft structural design should be such that excessive loads will not be imposed upon the engine face flange due to aircraft deflections under the maximum flight maneuvering or landing conditions. These same design concerns must be satis
27、fied if a flexible seal is employed to join the inlet duct to the engine front face. 2-3.2.3 V The aircraft inlet design usually represents a compromise between maximum recovery at hovering and at maximum forward flight speed. Proper design of the diffuser permits the selection of a reduced inlet ca
28、pture area and avoids excessive spill drag penalities at high flight speeds. Flow field effects 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-due to aircraft attitude and rotor downwash can adversely impact inlet recovery and the full range of fl
29、ight conditions, including maximum rate of climb flight, for example, must be considered. In addition to maximizing the pressure recovery, the inlet location on the aircraft is influenced by the flow fields and exhaust plumes during weapons firing, potential for ingesting recirculated engine exhaust
30、 gas, and susceptibility to FOD generated by the rotor downwash close to the ground. 2-3.2.4 Pressure Distortion/Swirl To minimize pressure distortion and swirl, when the engine output shaft is at the front of the engine and the inlet duct must wrap around the shaft or a nose gearbox, the inlet duct
31、 must be of adequate length to permit a relatively gradual diffusion and lowering of the velocity of the air entering the engine. These type inlets may employ vanes or splitters in the duct for flow straightening ahead of the engine face. Immediately before the engine face, a very short accelerating
32、 section of the inlet duct is often used to reduce flow distortion. Special inlet design features may be required to accommodate the high rate of change of pressure and temperature that can be experienced during ingestion of armament gases caused by weapons firings. The limits for rate of change of
33、inlet pressure and temperature are usually contained in the engine specification. 2-3.2.5 FOD Protection, For non bypass inlet systems-; a FOD screen and actuated FOD/ice shield should prevent hard objects larger than 6 mm in diameter and soft objects such as grass, leaves, and rags from entering th
34、e engine inlets or the engine air/oil cooler inlets. Screens should either be designed to not accrue ice formation or should be heated to prevent ice accumulation. The FOD screen should be compatible with aircraft RCS design requirements, if applicable. For bypass inlet systems, sufficient direct ai
35、rflow and/or scavenge/ejector air flow should be provided to assure that foreign objects, including ice, do not enter the engine. . 2-3.2.6 Ui-icing, An anti-icing subsystem is required for the engine inlet(s), lips and ducts, at the conditions specified in environmental section of the applicable we
36、apon or the engine system specification. The anti-icing system may be either electrical or bleed air type systems. Either system should maintain a surface temperature of at least 40F. Provisions should be made to drain melted ice from the interior of the inlet to prevent ice water from refreezing an
37、d subsequently being ingested into the engine. The anti-icing system should be capable of operating during all flight and ground operations at all engine power conditions. If operational failure of the anti-icing system occurs, it should remain in, or revert to, the anti- icing mode. One control sho
38、uld activate all ice protection systems. Cockpit indication should verify operation of the anti-icing subsystem. 2-3.3 muet Svstem. Attachments should be designed to allow for thermal expansion and tailpipe deflections throughout the aircraft operating envelope. All exhaust outlets should be provide
39、d with watertight plugs and/or covers for protection during aircraft nonuse. If the exhaust system includes an infra-red suppresser (IRS), the IRS should: a. Meet the engine exhaust system hot metal and plume IR.signature requirements. b. Cool and direct engine exhaust such that the system does not
40、represent a fkre hazard to ground vegetation or a safety hazard to personnel refueling or re- Srining the aircraft with the engines running. c. Prevent loss of tail rotor efficiency due to hot exhaust gas flowing through the tail rotor. d. Prevent loss of power due to heating of inlet air and/or rei
41、ngestion. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2-3.4 PrODUlS ion Svstem Cont rob. 2-3.4.1 Fuel System Controls. The pilot should have complete control of any combination of fuel tanks, including external/internal auxiliary tanks. The eng
42、ine shut-off fuel feed system and the engine power control off position should be interlocked with the fire extinguisher and fire handle such that movement of the latter shuts off fuel flow both at the engine control and at the firewall shut-off valve. Control of external auxiliary tank fuel, such a
43、s transfer and shutoff should be provided in the cockpit display. fuel tanks (internal and external). The display should provide both graphic and alphanumeric presentation of the active fuel system, depicting valve position, fuel remaining in each tank, total fuel remaining, fuel boost/prime (if app
44、licable), and transfer in progress. Normal fuel shutoff should be initiated when the engine control lever (ECL) is retarded to the detent (STOP) position in any cockpit station. Emergency fuel shutoff should be initiated in any cockpit at the appropriate fire warning annunciator. Upon indication of
45、engine fire, the annunciator is pressed to effect a shutoff of fuel at the firewall of the.engine-and at the fuel control valve, and to arm the fire extinguisher for routing to the selected engine. should permit the crew to maintain eyes up and out of the cockpit during the transition of reducing po
46、wer to a single engine, and should-simplify crew response to pressing a single illuminated push-button to achieve fuel shutoff. Control should be provided for any combination of This methodology 2-3.4.2 APU Controb. APU start/stop control should be provided by a switch in the crewstation. The switch
47、 should provide a control signal to the APU engine control unit (ECU) to initiate the engine start sequence. The ECU should provide a signal for crewstation indication when the SPU has a successful start and is operating. The switch should provide a control signal to the ECU and to initiate an order
48、ly shutdown of the APU. The APU should be capable of being started without electrical power (i .e., back-up starting) . 2-3.4.3 -ter Contra. The aircraft should be secured via an unique “ignition key“ such that, with the key in the “off“ position, the ignition source can not be activated. Fuel flow
49、should be controlled via the engine throttle llstop cock1 position. This configuration should allow for engine water wash (without ignition spark) and ignition checks (without fuel flow) while maintaining the functionality of the ignition key. Start software/logic should prevent actuation of ignition out-of- sequence; i.e., if fuel flow is initiated by moving the engine throttle .with the ignition key in the off position, software should prevent ignition spark should the ignition key be turned to “sta
