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i. The rate of change of simulator instrument readings and of control forces should correspond to the rate of change which would occur on the applicable airplane under actual flight conditions for any given change in forces applied to the controls, in the applied power, or in airplane configurations.
j. Control forces and degree of control travel should correspond to that which would occur in the airplane under actual fight conditions.
k. Any simulator qualified by the NSPM must meet the requirements of FAR 121.407. The daily preflight should be documented either in the daily log or in a location easily accessible for review.
3. MOTION SYSTEM. A motion system having a minimum of three degrees of freedom shall be installed and operative. A means for recording the motion response time for comparison with actual airplane data should be incorporated.
4. VISUAL SYSTEMS.
a. The visual system should be capable of meeting all the standards of this appendix and Appendices 5 and 6 (Performance and Functional Appendices).
b. The optical system should be capable of providing at least a 45 degree field of view simultaneously for each pilot.
c. Visual systems evaluated and approved under AC 121-14C and subsequent circulars should incorporate a means for recording the visual response time for comparison with actual airplane data. Visual system response time is defined as the completion of the visual system display scan of the first video field containing different information resulting from an abrupt control input.
d. Operators should provide information concerning the representation of visual scenes at precision NAVAID weather minimums. The information provided should indicate proper location of the glide slope transmitter for specified runways, cockpit visual cut-off angle, relative pilot eye height to main landing gear in an approach configuration, and relative height of the glide slope antenna to the main landing gear in the approach configuration at Category II minimums. Operators should indicate in their ATG how their calculations are used to develop the
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For the NSPM to qualify precision weather minimum accuracy on simulators qualified under previous advisory circulars, operators should provide the NSPM with the methods to verify the accuracy of the visual scene.
APPENDIX 2. PHASE I SIMULATOR STANDARDS
1. DISCUSSION. In addition to the Basic simulator standards included in Appendix 1 of this advisory circular, all Phase I simulators must meet the standards of this appendix.
2. SIMULATOR - GENERAL. Phase I simulators require additional aerodynamic programming to include:
a. Ground effect -- for example: roundout, flare, and touchdown. This requires data on lift, drag, and pitching moment in ground effect.
b. Ground reaction -- reaction of the airplane upon contact with the runway during landing to include strut deflection, tire friction, and side forces.
c. Ground handling characteristics -- steering inputs to include crosswind, braking, thrust reversing, deceleration, and turning radius.
d. Multichannel recorders capable of recording Appendix 5 performance tests.
3. MOTION SYSTEM. Special effects programming to include:
a. Runway rumble, oleo deflections, effects of groundspeed and uneven runway characteristics.
b. Buffets on the ground due to spoiler/speedbrake extension and thrust reversal.
c. Bumps after lift-off of nose and main gear.
d. Buffet during extension and retraction of landing gear.
e. Buffet in the air due to flap and spoiler/speedbrake extension.
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f. Approach-to-stall buffet.
g. Touchdown cues for main and nose gear.
h. Nosewheel scuffing.
i. Thrust effect with brakes set.
4. VISUAL SYSTEM.
a. The visual system must provide visual cues to assess sink rate and depth perception during landing.
APPENDIX 3. PHASE II SIMULATOR STANDARDS
1. DISCUSSION. In addition to the Basic and Phase I standards included in Appendices 1 and 2 of this advisory circular, all Phase II simulators must meet the standards of this appendix.
2. PHASE II TESTS/STATEMENTS OF COMPLIANCE. The simulator and visual requirements listed in this appendix require a statement of compliance and, is some designated cases, a supporting test.
Compliance statements will describe how the requirement is met, such as gear modeling approach, coefficient of friction sources, etc.
3. SIMULATOR REQUIREMENTS.
a. Expanded simulator computer capacity, accuracy, resolution, and dynamic response to meet Phase II demands.
Resolution equivalent to that of at least a 32-bit word length computer is required for critical aerodynamic programs.
b. Representative modeling of crosswind and 3-dimensional windshear dynamics based on airplane related data. The use of volumetric three-dimensional windshear data (three-dimensional) is recommended over the two-dimensional, three component windshear profiles.
c. Representative stopping and directional control forces for at least the following runway conditions based on airplane related data. The compliance statement should be supported by tests with recorded results of stopping times and distances.
(1) Dry.
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(2) Wet.
(3) Icy.
(4) Patchy wet.
(5) Patchy icy.
(6) Wet on rubber residue in touchdown zone.
d. Representative brake and tire failure dynamics (including antiskid) and decreased brake efficiency due to brake temperatures based on airplane related data.
e. A means for quickly and effectively testing simulator programming and hardware. This could include an automated system which could be used for conducting at least a portion of the tests in the ATG.
f. Timely permanent update of simulator hardware and programming subsequent to airplane modifications.
g. Sound of precipitation and significant airplane noises perceptible to the pilot during normal operations and the sound of a crash when the simulator is landed in excess of landing gear limitations.
h. Performance tests are required to verify that control feel dynamics represent the airplane simulated. Dynamic damping cycles (free response of the controls) shall match that of the aircraft within 20% of the period and damping. Initial/upgrade evaluations will require that control free response dynamics (column, wheel, and pedal) be measured at and recorded directly from the controls, and correspond to that which would occur in the airplane in the takeoff, cruise, and landing configurations.
For airplanes with irreversible control systems, measurements may be obtained on the ground if proper pitot static inputs are provided to represent airspeeds typical of those encountered in flight. Likewise, it may be shown that for some airplanes, takeoff, cruise, and landing configurations have like effects.
Thus, one may suffice for another. If either or both considerations apply, engineering validation or airplane manufacturer rationale will be submitted as justification to ground test or for eliminating a configuration. For simulators requiring static and dynamic tests at the controls, special test fixtures will not be required during initial evaluations if the operator's ATG shows both test fixture results and alternate approach for results, such as computer plots which were conducted concurrently during the simulator tests and which showed agreement. Repeat of the alternate method during the initial evaluation would then satisfy this test requirement. (See Appendix 5, para 2.b(1) for additional information.)
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i. A test to verify that radio navigation aids are properly oriented to the airport runway layout. One VOR and one ILS localizer for one airport area must be shown by airport runway diagram or other appropriate source data to be accurate to within plus or minus 1% of VOR range and plus or minus 1 degree of bearing to the VOR and the ILS localizer measured from the point where the glide slope merges with the runway centerline with the simulated aircraft aligned with the centerline of the visual runway. Computer readouts are preferred to flight instrumentation.
j. Relative responses of the motion system, visual system, and cockpit instruments shall be coupled closely to provide integrated sensory cues. These systems shall respond to abrupt pitch, roll, and yaw inputs at the pilot's position within 150 milliseconds of the time, but not before the time, when the airplane would respond under the same conditions. Visual scene changes from steady state disturbance shall not occur before the resultant motion onset but within the system dynamic response tolerance of 150 milliseconds. The test to determine compliance with these requirements shall include simultaneously recording the analog output from the pilot's control column, wheel, and rudders, the output from an accelerometer attached to the motion system platform located at an acceptable location near the pilot's seats, the output signal to the visual system display (including visual system analog delays), and the output signal to the pilot's attitude indicator or an equivalent test approved by the Administrator. The test results in a comparison of a recording of the simulator's response to actual airplane response data in the takeoff, cruise, and landing configuration. The intent is to check the architecture of the hardware and software to determine that there are no detrimental transport delays and that the cues of motion and vision relate to actual aircraft responses. For aircraft response, acceleration in the appropriate rotational axis is preferred. Ten percent of peak acceleration is suggested as an appropriate response point.
4. MOTION SYSTEM REQUIREMENTS.
a. A motion system which produces cues at least equivalent to those of a six degree of freedom synergistic platform motion system.
5. VISUAL SYSTEM.
a. Continuous minimum visual field of view of 75 degrees horizontal and 30 degrees vertical per pilot seat. Both pilot
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b. Visual system test procedures to quickly confirm visual system color, RVR, focus, intensity, level horizon, and attitude as compared to the simulator attitude indicator.
c. A minimum of ten levels of occulting. This capability should be demonstrated by a visual model through each channel.
d. For additional information concerning visual system requirements, refer to FAR 121, Appendix H, and related material.
APPENDIX 4. PHASE III SIMULATOR STANDARDS
1. DISCUSSION. In addition to the Basic and Phase I and Phase II standards included in Appendices 1, 2 and 3 of this advisory circular, all Phase III simulators must meet the standards of this appendix.
2. PHASE III TESTS/STATEMENTS OF COMPLIANCE. The simulator and visual requirements listed in this appendix require a statement of compliance and, in some designated cases, a supporting test.
Compliance statements will describe how the requirement is met, such as gear modeling approach, coefficient of friction sources, etc.
3. SIMULATOR REQUIREMENTS.
a. Characteristic buffet motions that result from operation of the airplane (for example, high-speed buffet, extended landing gear, flaps, nose-wheel scuffing, stall) which can be sensed at the flight deck. The simulator must be programmed and instrumented in such a manner that the characteristic buffet modes can be measured and compared to airplane data. Airplane data are also required to define flight deck motions when the airplane is subjected to atmospheric disturbances such as rough air and cobblestone turbulence. General purpose disturbance models that approximate demonstrable flight test data are acceptable. An objective test with recorded results is required.
b. Aerodynamic modeling for aircraft for which an original type certificate is issued after June 1980, including lowaltitude level-flight ground effect, mach effect at high altitude, effects of airframe icing, normal and reverse dynamic thrust effect on control surfaces, aero-elastic representations, and representations of nonlinearities due to side slip based on
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c. Realistic amplitude and frequency of cockpit noises and sounds, including precipitation, static discharge, and engine and airframe sounds. The sounds shall be coordinated with the weather representations required in FAR Part 121, Appendix H, Phase III visual requirement No. 3. A test with recorded results is required.
d. Self-testing for simulator hardware and programming to determine compliance with simulator performance tests as prescribed in Appendix 5. Evidence of testing must include simulator number, date, time, conditions, tolerances, and appropriate dependent variables portrayed in comparison to the airplane standard. Automatic flagging of "out-of-tolerance" situations is encouraged.
e. Diagnostic analysis printouts of simulator malfunctions sufficient to determine MEL compliance. These printouts shall be retained by the operator between recurring FAA simulator evaluations as part of the daily discrepancy log required under FAR 121.407(a)(5).
4. VISUAL SYSTEM REQUIREMENTS.
a. Daylight, dusk, and night visual scenes with sufficient scene content to recognize airport, the terrain, and major landmarks around the airport and to successfully accomplish a visual landing. The daylight visual scene must be part of a total daylight cockpit environment which at least represents the amount of light in the cockpit on an overcast day. Daylight visual system is defined as a visual system capable of producing, as a minimum, full color presentations, scene content comparable in detail to that produced by 4,000 edges or 1,000 surfaces for daylight and 4,000 light points for night and dusk scenes, 6- foot lamberts of light at the pilot's eye (highlight brightness), 3-arc minutes resolution for the field of view at the pilot's eye, and a display which is free of apparent quantization and other distracting visual effects while the simulator is in motion. The simulator cockpit ambient lighting shall be dynamically consistent with the visual scene displayed. For daylight scenes, such ambient lighting shall neither "washout" the displayed visual scene nor fall below 5-foot lamberts of light as reflected from an approach plate at knee height at the pilot's station and/or 2-foot lamberts of light as reflected from the pilot's face. All brightness and resolution requirements must be validated by an objective test.
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b. Phase II visual requirements in daylight as well as dusk and night representations.
c. For additional information concerning visual systems requirements, refer to FAR 121, Appendix H, and related material.
APPENDIX 5. SIMULATOR PERFORMANCE TESTS
1. DISCUSSION. Simulator performance and system operation should be objectively evaluated by comparing each performance test conducted in the simulator to airplane performance. The performance of nonvisual and visual simulators should be compared to the best airplane performance data available for each test.
Phase I, II, and III simulators should be compared to flight test data. This will be accomplished by matching each flight test condition and response in the simulator.
To facilitate the comparison of performance between the simulator and the airplane, a multichannel recorder or line printer should be used to record each performance test in the simulator. The result of the multichannel recorder or line printer should be compared to the source data to confirm simulator performance.
The ATG provided by the operator should describe clearly and distinctly how the simulator will be set up and flown to accurately duplicate the flight test data. Use of a driver program designed to automatically duplicate the flight test with accuracy and dependability is encouraged, but procedures should be included to positively determine that the driver is doing nothing more than accurately flying the simulator. All test results should, therefore, reflect the real time output to the flightcrew so that the simulator would be in trim and would continue to fly if the driver was disengaged. This appendix contains the tests and tolerances which should be included in the operator's ATG. Phase I, II and III simulators will be compared to flight test data in all tests. For aircraft certificated prior to June 1980, an operator may, after reasonable attempts have failed to obtain suitable flight test data, indicate to the NSPM in the ATG where flight test data is unavailable or unsuitable for a specific test. For such a test, alternative data should be submitted in the ATG to the NSPM for approval.
Submittals for approval of data other than flight test must include an explanation of validity with respect to available flight test information. The tolerances specified in the following table of performance tests generally indicate the test results required such as static or dynamic time history. In the
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Unless otherwise indicated, tests should represent aircraft performance at normal operating weights and centers of gravity.
If a test is supported by aircraft data at one extreme gross weight or center of gravity, another test supported by aircraft data as close as possible to the other extreme should be included.
2. BASIC SIMULATOR PERFORMANCE TESTS. The ground and flight tests which should be evaluated, as appropriate to the type of airplane, are listed below. Dynamic tests are those tests which involve comparison of simulator to airplane performance over continuous time (time history). Recorded time histories are not required for basic visual and previously approved nonvisual simulator evaluations. However, simulator computer generated results should be provided to validate simulator performance for each test in this appendix. The results should be produced on a multichannel recorder, line printer, or other computer generated "hard copy" results acceptable to the NSPM. Simulator results should be labeled using the tolerances and units listed in this appendix.
Although tolerances may be specified for dynamic tests, other criteria such as general trends (such as over-shoots) and signatures of flight variable are of major consideration. It should be understood that even for static tests, airplane and or simulator data can be, and usually is, obtained from a dynamic exercise.
Where an asterisk(*) appears in the tolerance column for a particular test, the following appropriate airplane and simulator parameters and tolerances should be available for comparison:
pitch angle and angle of attack + or - 1 1/2 degrees roll angle + or - 2 degrees yaw angle + or - 2 degrees airspeed + or - 3 KTS altitude: 0-100 feet, + 10 feet; 100-500 feet, + or - 10%;
500 feet and above, + or - 50 feet maximum The nature of dynamic flight test data will require normalizing of some traces and subsequent judicious application of the above tolerances. When difficulties arise in matching simulator
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NOTES: 1. All airspeeds should be clearly annotated as to indicated, calibrated, etc. Like types of airspeed will be offered for comparison in any test.
2. Where 2 tolerances are given, the less restrictive may be used unless otherwise indicated.
a. FLIGHT CONDITION CODES.
(1) Ground/Takeoff
(2) First Segment Climb
(3) Second Segment Climb (if applicable to flap change)
(4) Enroute Climb
(5) Cruise
(6) Descent
(7) Approach
(8) Landing FLIGHT
b. SIMULATOR TEST TOLERANCE CONDITIONS
(1) STATIC CONTROL CHECKS.**
(a) Column Position + or - 2 degree vs Force and Elevator Surface Position + or - 5 lbs or Calibration 10% 1
(b) Wheel Position vs + or - 1 degree Aileron Force and Surface + or - 2 degrees Spoiler Position + or - 3 lbs or 10% Calibration;
(c) Rudder Pedal Position vs Force and Surface + or - 2 degrees Rudder Position + or - 5 lbs or Calibration; 10% 1
(d) Nosewheel Steering + or - 3 lbs or Force 10% 1
(e) Rudder Pedal Steering + or - 5 lbs or
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(f) Pitch Trim Calibration Indicator vs Computed + or - 1/2 degree 1
(g) Alignment of Power Lever + or - 5 degrees 1 Angle or Cross Shaft Angle vs Selected Engine Parameter (EPR, N1) ** Column, wheel and pedal position vs force shall be measured at the controls. An alternate method acceptable to the NSPM in lieu of the test fixture at the controls would be to instrument the simulator in an equivalent manner to the flight test airplane. The force and position data from this instrumentation can be directly recorded and matched to the airplane data. Since this is a permanent installation, it can be used over and over without any time for installation of external devices.
(2) TAKEOFF.
(a) Ground Acceleration + or - 5% time and Time and Distance distance or + or - 5% of time and + or - 200 ft.
of distance 1
(b) Minimum Control Speed, Ground + or - 5 knots 1
(c) Minimum Rotate Speed + or - 3 knots 1
(d) Minimum Unstick Speed + or - 3 knots 1
(e) Types of Takeoff Required through 500 feet AGL 1 Normal * 1 and 2 2 Engine Out Takeoff * 1 and 2 3 Crosswind Takeoff * 1 and 2
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(3) CLIMB.
(a) Normal climb + or - 5% climb rate 4 or 100 FPM whichever is greater
(b) Engine Out Second " 3 Segment Climb
(c) Engine Out Approach " 7 Climb
(4) LONGITUDINAL CONTROL.
(a) Power Change Forces + or - 5 lb. or 5 + or - 20% or Power Change Dynamics + or - 20% or + or - 1-1/2 degree pitch, + or - 3 kts., + or - 100'/min.
(b) Flap Change Forces + or - 5 lbs or 3 and;
20% 7 or 8 or Dynamics + or - 20% or + or - 1-1/2 degree, + or - 3 kts, + or - 100'/min.
(c) Gear Change Forces + or - 5 lbs or 1 and + or - 20% or Gear Change Dynamics + or - 20% or + or - 1-1/2 degree, + or - 3 kts, + or - 100'/min.
(d) Gear and Flap Operating Times + or - 3 sec or 1 and 7 + or - 20% Time
(e) Longitudinal Trim + or - 1 unit trim;
1 degree pitch; 7 and 8 .05 EPR
(f) Longitudinal + or - 5 lbs or Maneuvering + or - 10% Stability (Stick Stick Force 5, 7 and 8 Force/G)