Aviation Electronics Europe - Munich 26 th March 2015 Situational Awareness latest and future challenges Low Air Speed Data

Transcription

1 Defense Solutions Division Aviation Electronics Europe - Munich 26 th March 2015 Situational Awareness latest and future challenges Low Air Speed Data Paul Hart CTO Curtiss-wright Avionics & Electronics 1 April 1, 2015 Proprietary 2015 Curtiss-Wright

2 Situational Awareness latest and future challenges Back to Basics Evolution of the Air Data Computer NextGEN/SESAR Challenges and Possible Solutions Helicopter situational awareness an additional set of challenges 2 April 1, 2015 Proprietary 2015 Curtiss-Wright

3 Back to Basics The Basic-T Instrument Panel 3 April 1, 2015 Proprietary 2015 Curtiss-Wright

4 ADC Air Data Computer & EFIS Electronic Flight Information System 4 April 1, 2015 Proprietary 2015 Curtiss-Wright

5 ADC Air Data Computer & EFIS Electronic Flight Information System Pitot Probe Symbol Generator IMA Processor Static Port Left Total Air Temperature (TAT) Probe Static Port Right Angle of Attack Vane Speed Tape Indicated Airspeed IAS knots/mach# Total Air Temperature Altitude Tape ft Instantaneous Vertical Speed IVSI 5 April 1, 2015 Proprietary 2015 Curtiss-Wright

6 Air Data Probes Angle of Attack (AoA) Sensors L&R Ice Detectors L&R TAT Probe Air Data Modules (inside fuselage) Combined Pitot-Static Probes - Captain First Officer & Standby 6 April 1, 2015 Proprietary 2015 Curtiss-Wright

7 Multiple Aircraft Systems use Air Data: EFIS Primary Flight Information Airspeed (knots, Mach), Altitude, Vertical Speed, Corrected AoA Flight Management System WPT/ETA calculation, Winds aloft, Range Constant/Specific Range calculation Passenger IFE Airspeed, Altitude, Outside Air Temperature Flight Warning Computer Stall Detection/Warning, Landing Gear, Flap Extension Flight Data Recorder Mandatory FDR parameters HUD Head Up Display Symbology Transponder Altitude Reporting Modes 1-5, Mode S, ADS-B EFB Electronic Flight Bag V 1 V R V 2 take off speed calculation Autopilot/Autothrottle Computer VNAV Modes, Throttle Lever Angle Clutch Control Surface Power Control Units Rudder Ratio gearing down actuator deflection with increasing airspeed, Q Feel 7 April 1, 2015 Proprietary 2015 Curtiss-Wright

8 Multiple Aircraft Systems use Air Data: EFIS Primary Flight Information Airspeed (knots, Mach), Altitude, Vertical Speed, Corrected AoA Flight Management System WPT/ETA calculation, Winds aloft, Range Constant/Specific Range calculation Passenger IFE Airspeed, Altitude, Outside Air Temperature Flight Warning Computer Stall Detection/Warning, Landing Gear, Flap Extension Flight Data Recorder Mandatory FDR parameters HUD Head Up Display Symbology Transponder Altitude Reporting Modes 1-5, Mode S, ADS-B EFB Electronic Flight Bag V 1 V R V 2 take off speed calculation Autopilot/Autothrottle Computer VNAV Modes, Throttle Lever Angle Clutch Control Surface Power Control Units Rudder Ratio gearing down actuator deflection with increasing airspeed, Q Feel 8 April 1, 2015 Proprietary 2015 Curtiss-Wright

9 Autothrottle Pitot TAT Static ADC Autothrottle Computer 9 April 1, 2015 Proprietary 2015 Curtiss-Wright

10 NextGEN & SESAR objectives getting closer together Pre minutes 2,000ft In-Trail Separation Vertical Separation Reduced Vertical Separation Minima (RVSM) - above 29,000ft (=Flight Level 290 = FL290) 10 April 1, 2015 Proprietary 2015 Curtiss-Wright

11 NextGEN & SESAR objectives getting closer together Pre-1995 Present day 10 minutes 5 minutes 1,000ft 2,000ft In-Trail Separation Vertical Separation Reduced Vertical Separation Minima (RVSM) - above 29,000ft (=Flight Level 290 = FL290) 11 April 1, 2015 Proprietary 2015 Curtiss-Wright

12 NextGEN & SESAR objectives getting closer together Pre-1995 Present day NextGEN& SESAR proposals: minutes 5 minutes 105 seconds 1,000ft 500ft 2,000ft In-Trail Separation Vertical Separation Reduced Vertical Separation Minima (RVSM) - above 29,000ft (=Flight Level 290 = FL290) 12 April 1, 2015 Proprietary 2015 Curtiss-Wright

13 NextGEN & SESAR objectives getting closer together Pre-1995 Present day NextGEN& SESAR proposals: minutes 5 minutes 105 seconds 2,000ft In-Trail Separation 1,000ft Vertical Separation Reduced Vertical Separation Minima (RVSM) - above 29,000ft (=Flight Level 290 = FL290) 500ft Air Data Computers/Modules will require minimum ±0.25 millibar accuracy to operate in specific proposed NextGEN/SESAR airspace. Equates to ±18ft altitude & ±0.35 knots IAS EUROCAE ED-140 EUROCAE Working Group April 1, 2015 Proprietary 2015 Curtiss-Wright

14 Improving Situational Awareness: High Accuracy Air Data Vibrating Cylinder Technology: Ultra high ±0.25mbar accuracy that exceeds RVSM and meets future NextGen / SESAR requirements Drift free and requires no calibration Low cost of ownership: No routine maintenance other than leak tests for pneumatic pipework connecting to ADC 14 April 1, 2015 Proprietary 2015 Curtiss-Wright Developed for Flight Critical Applications: DO-178C Level A Software DO-254 Level A Hardware ARP4754 Safety Certified - Meets 1 in Probability of Hazardously Misleading Information SIL3 Compliant Dual Core Processor (TMS570) with duplicate application running in lock-step. Crosscomparison for each line of code execution Extensive continuous built in test, loopback checking, CRC checking, windowed watchdog

15 Vibrating Cylinder Technology Air Data Computer Baro Correction: ARINC 575 potentiometer or ARINC 429 ±0.07% Measurement Accuracy (Baro Pot) to 745 mbar (equivalent to to feet) TAT Inputs: 100 (BS.3G148) 130 (BS.2G148) 500 (ARINC 706-4) Weight: 0.6kg /1.3lb max. Dimensions: 170Lx110Wx430H mm 6.7 Lx4.4 Wx1.7 H 15 April 1, 2015 Proprietary 2015 Curtiss-Wright ADC parameter outputs: ARINC 429: 12.5/100kbps Flight Critical Ethernet: ARINC664P7 End-System MIL-STD-1553B Remote Terminal Static Pressure (Ps) Pressure Altitude (H) Vertical Speed (H') Maximum Allowable Airspeed (Vmo) Barometric Corrected Altitude (Hbc) Barometric Correction Differential Pressure (qc) Total Pressure (Pt) Indicated Airspeed (Vi) Computed Airspeed (Vc) Mach Number (M) Total Outside Air Temperature ( t) Static Outside Air Temperature ( s) True Airspeed (Vt) Indicated Angle of Attack Corrected Angle of Attack

16 Improving Situational Awareness: Enhanced Fault Isolation Static holes (x6) around the tube circumference null out pressure differentials at different angles of attack Central port is piped to main Pitot sensor for IAS/Mach measurement Delta P ports above and below the central port connect to a differential pressure sensor in the ADC to provide Angle of Attack 16 April 1, 2015 Proprietary 2015 Curtiss-Wright

17 Air Data Source Selection Standby Flight Display System P S Captain EICAS First Officer Primary Flight Display Navigation Display Engine Instrument & Primary Flight Display Navigation Display Crew Alerting System CAPT F/O CAPT F/O TAT AoA ADC ADAHRS ADIRS ADC ADAHRS ADIRS 17 April 1, 2015 Proprietary 2015 Curtiss-Wright

18 EFIS: Left/Right Disagreement Standby Flight Display System CHECK IAS P S Captain EICAS First Officer Primary Flight Display Navigation Display Engine Instrument & Primary Flight Display Navigation Display Crew Alerting System CAPT F/O CAPT F/O TAT AoA ADC ADAHRS ADIRS ADC ADAHRS ADIRS 18 April 1, 2015 Proprietary 2015 Curtiss-Wright

19 EFIS: Left/Right Disagreement Standby Flight Display System CHECK IAS P S Captain EICAS First Officer Primary Flight Display Navigation Display Engine Instrument & Primary Flight Display Navigation Display Crew Alerting System CAPT F/O CAPT F/O TAT AoA ADC ADAHRS ADIRS ADC ADAHRS ADIRS 19 April 1, 2015 Proprietary 2015 Curtiss-Wright

20 Improving Situational Awareness: Fault Tolerant Networked Sensors Standby Flight Display System P S Captain EICAS First Officer Primary Flight Display Navigation Display Engine Instrument & Primary Flight Display Navigation Display Crew Alerting System CAPT F/O CAPT F/O TAT AoA ADC ADAHRS ADIRS ADC ADAHRS ADIRS 20 April 1, 2015 Proprietary 2015 Curtiss-Wright

21 Improving Situational Awareness: Fault Tolerant Networked Sensors Standby Flight Display System CAPT PITOT INOP P S Captain EICAS First Officer Primary Flight Display Navigation Display Engine Instrument & Primary Flight Display Navigation Display Crew Alerting System CAPT F/O CAPT F/O TAT AoA ADC ADAHRS ADIRS ADC ADAHRS ADIRS 21 April 1, 2015 Proprietary 2015 Curtiss-Wright

22 Which Airborne Network? (must be DAL A certified: Flight Critical) ARINC 629 Early 1990s technology. Only adopted on single aircraft type MIL-STD-1553B Command/Response, more for military avionics, mission systems ARINC 825 CAN Bus CANbus (Controller Area Network) widespread and most established in automotive industry TTE - Time Triggered Ethernet Time Triggered Protocol 4Mbps Ethernet Deterministic, time synchronised. Uses RS485 as physical layer Star topology, dual redundant Flight Critical Ethernet - ARINC664Pt7 100Mbps. Copper and Fibre Implementations 22 April 1, 2015 Proprietary 2015 Curtiss-Wright

23 Helicopter Air Data Probe Locations Agusta A109 Sikorsky S-76 Optimal location for Static Ports is slightly aft of the rotor Pitot Probes are positioned forward as disc centreline with the least downwash effect practical to minimise source errors Eurocopter EC155 Co-Pilot and Standby Pitot Probes can be combined on the same stalk to reduce the fuselage attachment points Sikorsky S-76 OAT probes, used to compute TAS are typically mounted on the underside of the fuselage to avoid errors from direct sunlight 23 April 1, 2015 Proprietary 2015 Curtiss-Wright

24 Helicopter Air Data Computers: Problems that need a Solution Different set of problems to fixed wing aircraft: 1. Instantaneous downwash increase when pilot applies collective shows as a negative Vertical Speed when the helicopter is in fact climbing 2. Rotor blade modulation gives approx 4Hz air pressure pulse/rev 3. Downwash from rotor blades at low airspeed make measurement impossible at low airspeed (<30kt) 24 April 1, 2015 Proprietary 2015 Curtiss-Wright

25 Helicopter Air Data Computers: Problems that need a Solution Different set of problems to fixed wing aircraft: 1. Instantaneous downwash increase when pilot applies collective shows as a negative Vertical Speed when the helicopter is in fact climbing 2. Rotor blade modulation gives approx 4Hz air pressure pulse/rev 3. Downwash from rotor blades at low airspeed make measurement impossible at low airspeed (<30kt) 25 April 1, 2015 Proprietary 2015 Curtiss-Wright

26 Helicopter Air Data Computers: Problems that need a Solution Different set of problems to fixed wing aircraft: 1. Instantaneous downwash increase when pilot applies collective shows as a negative Vertical Speed when the helicopter is in fact climbing 2. Rotor blade modulation gives approx 4Hz air pressure pulse/rev 3. Downwash from rotor blades at low airspeed make measurement impossible at low airspeed (<30kt) 26 April 1, 2015 Proprietary 2015 Curtiss-Wright

27 Helicopter Air Data Computers: Problems that need a Solution Different set of problems to fixed wing aircraft: 1. Instantaneous downwash increase when pilot applies collective shows as a negative Vertical Speed when the helicopter is in fact climbing 2. Rotor blade modulation gives approx 4Hz air pressure pulse/rev 3. Downwash from rotor blades at low airspeed make measurement impossible at low airspeed (<30kt) 27 April 1, 2015 Proprietary 2015 Curtiss-Wright

28 LASP Low AirSpeed Probe LASP is installed on the tail rotor tail fin or fenestron High Accuracy Air Data Computer(s) connect to existing pitot probes and static ports 28 April 1, 2015 Proprietary 2015 Curtiss-Wright LASP output connects to Air Data Computers (single or dual installation) which merges the sensor data to produce a high accuracy output to EFIS & Flight Control (SAS/AFCS)

29 LASP: Low AirSpeed Probe How it works 1 2 LASP operates by measuring the time of flight of an ultrasonic sound pulse deflected off a top-plate, known as the parabola. The reason for the 45 degree up and down sound path is to remove any vertical airspeed component. If there is a downwind component, the sound pulse will arrive at the receiver faster than if the surrounding air was static. Conversely, the pulse is slowed down if the airflow is directly towards the transducer Once the first pulse is detected, the time of flight is calculated, the ultrasonic receiver is then re-configured as a transmitter and a pulse is transmitted back the same way. The reason is to remove any common mode errors, such as humidity and temperature effects that would affect the measurement of a single point-to-point transmission. Parabola Ultrasonic Transducers 29 April 1, 2015 Proprietary 2015 Curtiss-Wright

30 LASP: Low AirSpeed Probe How it works 3 By having transmit/receive pairs positioned at 90 degrees, it is possible to resolve the wind vectors and the x and y axes and compute windspeed and direction. The transmitters and receiver operate on a continuous sequence, interleaving each of the 4 measuring paths 30 April 1, 2015 Proprietary 2015 Curtiss-Wright

31 LASP: Low AirSpeed Probe How it works 4 LASP measures the vector of forward airspeed component and windspeed & direction Forward Speed Indicated Air Speed An AHRS input is used for lever arm correction (e.g. to remove errors due to helicopter yaw) and bank angles 31 April 1, 2015 Proprietary 2015 Curtiss-Wright

32 Helicopter Air Data System: ADC+LASP with Kalman Filter Kalman filter (in ADC) uses weighting algorithm to provide highest accuracy airspeed across operating range Auto cross-comparison between dual ADCs, single LASP and GPS (derived Groundspeed) used for error checking LASP will also provide negative airspeed output in reverse flight 0 10kt 20kt 30kt 40kt 50kt 60kt 70kt+ Accuracy ±3.0kt Accuracy ±3.5kt Accuracy ±4.0kt Accuracy ±4.5kt Accuracy ±2.5kt Accuracy ±1.9kt IAS measurement transitions to LASP at Low Airspeed ADC provides IAS above 35-50kt 32 April 1, 2015 Proprietary 2015 Curtiss-Wright

33 Conventional EFIS Symbology does not depict IAS Vector 33 April 1, 2015 Proprietary 2015 Curtiss-Wright

34 Proposed Helicopter EFIS Symbology /21 34 April 1, 2015 Proprietary 2015 Curtiss-Wright

35 Proposed Helicopter EFIS Symbology /21 Wind Direction & Speed Vane Forward Speed Indicated Air Speed Apparent Windspeed and Vector 35 April 1, 2015 Proprietary 2015 Curtiss-Wright

36 Helicopter Low Airspeed Probe Dual ADC+LASP Pitot Pneumatic Tubing Static Pneumatic Tubing ARINC 429 RS422 Analog Combined Right Pitot and SBY Left Pitot Left ADC Right ADC Standby Static Port Cross-Compare Bus Left Static Port Outside Air Temp probe Mounted underneath fuselage (out of direct sunlight) Right OAT Probe LASP - Low Airspeed Probe Mounted on Tail Rotor Fin Right Static Port 36 April 1, 2015 Proprietary 2015 Curtiss-Wright

37 Helicopter Low Airspeed Probe Dual ADAHRS+LASP Pitot Pneumatic Tubing Static Pneumatic Tubing ARINC 429 RS422 Analog Combined Right Pitot and SBY Left Pitot Left ADAHRS Right ADAHRS Standby Static Port Cross-Compare Bus Left Static Port Outside Air Temp probe Mounted underneath fuselage (out of direct sunlight) Right OAT Probe LASP - Low Airspeed Probe Mounted on Tail Rotor Fin Right Static Port 37 April 1, 2015 Proprietary 2015 Curtiss-Wright

38 Defense Solutions Division Thank You! Paul Hart Q&A CTO Curtiss-wright Avionics & Electronics 38 April 1, 2015 Proprietary 2015 Curtiss-Wright