Appendix 3 Table 3 – Foreign Airports and Runways Approach Category, Airport Name/Identifier, Runway(s) Limitations
j. Runway Restrictions. The certificate holder is authorized to conduct the operations in subparagraph a using autoland or FP HUD landing systems into the restricted U.S. facilities listed in Table 4 below.
Table 4 – Restricted/Nonstandard U.S. Facilities Approach Category, Airport Name/Identifier, Runway(s) Limitations
k. Maintenance. The certificate holder must maintain the airplanes and equipment listed above in Table 1 and, if applicable, Table 2, in accordance with its approved Lower Landing Minimums (LLM) maintenance or inspection program.
l. Engine Inoperative Operations. The certificate holder is approved for operations authorized in subparagraph a with an inoperative engine using the airplanes and limitations specified in Table 5 below.
Table 5 – Engine Inoperative Operations Airplane M/M/S Operational Authorization Limitations
[Select the following text, if applicable.]
m. Hybrid CAT III Operations. The certificate holder is authorized to conduct CAT III operations using Autoland and Head-Up-Guidance Systems (HGS) together as a Hybrid Landing system. All Hybrid CAT III operations must be conducted in accordance with the approved Hybrid Landing system training programs, operating manuals, and maintenance programs.
CAT III Hybrid operations may be conducted to minimums as low as TDZ RVR 400 (125m), mid RVR 400 (125m) and rollout RVR 300 (75m), in accordance with subparagraph b.
Appendix 4 APPENDIX 4. IRREGULAR TERRAIN ASSESSMENT
1. General. The following information describes the operational evaluation process, procedures, and criteria used in approving flight guidance systems (FGS) (e.g., autoland or Head-Up Display (HUD)) supporting Category (CAT) II/III procedures and minima at restricted airports. These airports have irregular underlying approach terrain and are identified on the FAA website under Restricted/Nonstandard U.S. Facilities Approved for Category II/III Operations at http://www.faa.gov/about/office_org/headquarters_offices/avs/offices/afx/afs/afs400/afs410/cat_ ils_info/.
a. This appendix describes the general evaluation process, procedures, and criteria to be applied during irregular terrain assessments. Since circumstances often are unique in assessing aircraft/FGS/site performance, this summary represents an acceptable method to determine acceptable performance at these “special terrain airports.” It is not the only method that may be proposed by the FAA or an applicant. Credit may be applied for relevant testing by the manufacturer for similar airborne systems or for performance at similar locations
(e.g., subsequent irregular terrain airport approvals). Certain aircraft/FGS combinations may require more extensive testing when an aircraft may exhibit unique characteristics at a particular runway (e.g., transient Radio Altimeter failure indication due to disagreement or unlock, inappropriate auto throttle response, inconsistent flare performance).
b. For aircraft not using autoland for CAT II operations, this evaluation consists primarily of ensuring availability of an appropriate method for identification of decision altitude (DA)/decision height (DH) (e.g., assessing acceptable radio altimeter indications approaching and at DA/DH, or substituting use of inner marker (IM) in lieu of radio altimeter). Assessing acceptable radio altimeter indications is done by ensuring sufficient radio altimeter display readout stability and continuity to easily read the radio altimeter when approaching DA/DH and at DA/DH, while over-flying the irregular underlying terrain. This assessment may typically be done during operations using weather minima no lower than CAT I, or may be based on operations at that runway by that operator with an equivalent radio altimeter installation
(e.g., previously in a B-757, for new B-767 operations), or may be based on other U.S. operators who have completed an assessment using the same aircraft type and radio altimeter system combination, or equivalent.
c. Accordingly, before establishing test requirements with a manufacturer or operator for irregular terrain airports or particular runways, the proposed evaluation plan should be coordinated with the Flight Technologies and Procedures Division. This should be done prior to any testing or data collection agreement by the operator’s principal operations inspector (POI) or principal avionics inspector (PAI).
2. FGS Evaluation Process at Irregular Terrain Airports or Runways Proposed for CAT II/III Autoland or HUD to Touchdown Procedures or Minima.
a. Case I—First of a Type/Model at Any Irregular Terrain Airport/Runway. Case I concerns the first time a particular aircraft type/model is to be approved for any irregular terrain airport/runway (e.g., the first B-787 autoland approval at any irregular terrain airports listed on
Appendix 4 the Restricted/Nonstandard U.S. Facilities Approved for Category II/III Operations spreadsheet on the FAA website).
(1) Evaluation Objective. Assess and verify normal FGS performance from an operational perspective, and identify miscellaneous factors needed for a safe CAT II/III Autoland or HUD to touchdown operation (e.g., Alert Height (AH) or DH identification).
(2) Procedure. Perform at least four to six successful evaluation landings (in nonrevenue service) in typical atmospheric conditions regarding wind and turbulence, using the applicable operational aircraft configuration, with a representative aircraft from the fleet (e.g., a typical aircraft maintained using routine maintenance practices, not specially configured, not specially tested, or otherwise not specially selected from the operator’s fleet). If the FGS may be susceptible to an uncertain performance characteristic (e.g., long flare in a tailwind condition, pitch/throttle coupling oscillation during flare) the evaluation should take place when the system may be put to an appropriate test of the applicable crosswind, tailwind, headwind, wind gradient, or other critical condition applicable, consistent with the operator’s proposed conditions or limits and the Airplane Flight Manual’s (AFM) demonstrated conditions or limits.
Confirm the initial assessment of four to six data recorded evaluation landings, with subsequent successful initial operational landings (typically the first 15 or more) as reported by the operator (e.g., data recording or other special observation, other than by the regularly assigned flightcrew, is not required).
(3) Evaluator(s). A person qualified to assess FGS function and performance should conduct these evaluations as the FAA observer (e.g., typically a CAT II/III Autoland or HUD to touchdown qualified and experienced aircrew program manager (APM) of a CAT II/III authorized operator, a qualified Aircraft Evaluation Division representative, or an appropriate FAA national resource specialist (NRS)). The FAA may designate other suitably qualified representatives to assess FGS function and performance as necessary (e.g., suitably qualified check pilot, fleet manager, FAA Designated Engineering Representative (DER)).
(4) FGS Performance/Data Recording. Generally, some form of quantitative data should be recorded and reviewed as verification of performance. Past methods of data collection include, but are not limited to, the three methods below or any combination:
(a) Method A - Data Recording and Observation. Record pertinent FGS performance data using a digital flight data recorder (DFDR), quick-reference recorder, or equivalent that has ability to record the parameters shown below. The recording should be at a sufficiently high sample rate (e.g., at a rate > 1 sample per second), for the part of the flightpath of interest (typically from 300 feet height above touchdown (HAT) through de-rotation after touchdown).
• Barometric altitude,
• Radio altitude,
• Radio altitude rate,
• Glide path error,
• Vertical speed,
Appendix 4
• Elevator command,
• Pitch attitude,
• Throttle position,
• Airspeed, and
• Mode transition or engagement.
M anual observations may be made for touchdown point (lateral, longitudinal), wind profile from 1000 feet to surface (e.g., from an inertial navigation system (INS) or IRS that is capable of displaying winds at typical approach speeds).
(
b) Method B - Review of Manufacturer’s Data. A review of the manufacturer’s data from FGS development flight testing at the same irregular terrain runway, or equivalent, may be used to confirm items shown in (5) below.
(c) Method C - Photo Recording. Photo recording of pertinent instruments or instruments and outside view, with a video camera or equivalent, allowing post flight replay and review of indications noted in Method A above.
(5) Data Review and Analysis. The final approach, flare, and touchdown profile should be reviewed to ensure suitability of at least each of the following:
(a) Suitability of the resulting flightpath;
(b) Acceptability of any flightpath displacement from the nominal path (e.g., glide path deviation, deviation from nominal flare profile);
(c) Proper mode switching;
(d) Suitable touchdown point;
(e) Suitable sink rate at touch down;
(f) Proper flare initiation altitude;
(g) Suitable flare “quality” (e.g., no evidence of early or late flare, no over-flare or under-flare, no undue “pitch down" tendency at flare initiation or during flare, no flare oscillation, no abrupt flare, no inappropriate pitch response during flare, no unacceptable floating tendency, or other unacceptable characteristic that a pilot could interpret as failure or inappropriate response of the FGS and disconnect, disregard, or contradict the FGS);
(h) No unusual flight control displacements (e.g., elevator control input spikes, or oscillations);
(i) Appropriate throttle retard (e.g., no early or late throttle retard, no failure to retard, no undue reversal of the retard, no undue pitch/throttle coupling);
Appendix 4
(j) Appropriate speed decay in flare (e.g., no unusually low speed risking high pitch attitude and tail strike, no excessive float, appropriate speed decay even if well above VREF at flare initiation due to planned wind or gust compensation); and
(k) Proper mode initiation or mode transition relating to altitude or radio altitude inputs (e.g. crosswind alignment initiation).
(6) Miscellaneous Issues.
(a) Determine acceptability of any variable radio altitude indications. Regarding AH or DH identification, determine the acceptability of any variable radio altitude indications or displays (e.g., considering variability due to underlying terrain variability in the last stage of the approach near AH or DH). Ensure that display indications are sufficiently stable and continuous to readily identify or define AH or DH. If an IM is used to establish AH or DH, determine if the IM function is adequate.
(b) Address any anomalies occurring during the assessment (e.g., autopilot trip, firm landing, flare oscillation, etc.). Additional testing may be needed to clearly identify and resolve any particular problem(s).
(c) Determine if special training or other operational constraints are needed to accommodate peculiar approach or flare characteristics (e.g., require visual reference at flare initiation, apply a 50 feet DH).
(d) Authorization for use should occur only after repeated successful landings have been demonstrated and any anomalies experienced have been resolved.
b. Case II - First of a Type/Model at Any Subsequent Irregular Terrain Airport/Runway. Case II concerns a particular type/model of aircraft previously approved at one of the irregular terrain airports, now seeking initial approval at a different irregular terrain airport/runway. (e.g., the first B-767 autoland approval at KPIT RWY 10L, after being previously approved at KSEA).
(1) Evaluation Objective. Same as Case I.
(2) Procedure. Same as Case I.
(3) Evaluator(s). Same as Case I.
(4) FGS Performance/Data Recording. Data recording is generally not required.
However, if the results of landings are marginal or unacceptable, the data recording and assessment procedures applicable to Case I may be needed to assess any remedial action required.
(5) Data Review and Analysis. Same as Case I.
(6) Miscellaneous Issues. Same as Case I.
Appendix 4
c. Case III - Subsequent Operator Use of a Particular Irregular Terrain Airport/Runway and Type Combination. Case III concerns an operator seeking approval for a particular irregular terrain airport/runway using an aircraft type/model previously approved by a different operator. (e.g., ABC airline requests approval of B-757 operations at KDEN RWY 34R.
This combination was previously demonstrated and approved by XYZ airlines).
The responsible Flight Standards office (e.g., POI, PAI, APM) may review a request for an operator to use a particular irregular terrain airport/runway and aircraft type, and with Flight Operations Branch concurrence, approve subsequent airline operation of a particular type at that irregular terrain airport/runway. Any authorization should be based on 15 or more successful “line” landings reported by the operator requesting authorization, in weather conditions not requiring credit for FGS system use. During this reporting period, the operator should not experience any unsuccessful landing attempts or failures. If problems or failures are encountered, then Case II or Case I procedures may be needed to resolve potential unique aircraft configuration, procedural, maintenance, or other effects that may be hindering successful operations.
d. Case IV – “Not-For-Minima Credit” Use of Irregular Terrain Airport/Runway and Type Combinations.
(1) “Not-For-Credit” use of “Irregular Terrain Airport/Runway and Type Combinations” applies to operators desiring to use an FGS (e.g., autoland or Flight Guidance HUD) at an Irregular Terrain Airport/Runway, but not for any landing minima credit (i.e., CAT I autoland or HUD to touchdown only).
(2) In this instance, a representative of the responsible Flight Standards office may evaluate the use during first line operations or specify that an operator representative
(e.g., technical pilot, qualified management pilot, or check pilot who is experienced with FGS operation and performance) assess and verify adequate FGS performance. This assessment should be completed prior to initiating routine operational use of the FGS to touchdown at each “Irregular Terrain” runway. It is desirable, but not necessary, that a qualified APM, or equivalent, witness each "irregular terrain airport" evaluation.
(3) The responsible Flight Standards office should request and review FGS reports from line crews for at least the first five line landings to confirm appropriate performance. If problems occur, processes for Cases I through IV may be needed to resolve problems depending on the severity and cause of problem (e.g., maintenance problem, unusual winds, lack of Air Traffic Service (ATS) critical area protection, problem with a modification to the FGS, use of a different associated component, such as substitution of a different and incompatible radio altimeter model).
(4) “Not-For-Credit” evaluation. A “Not for Credit” evaluation may be done in line operation as long as no previous reported problems have been noted with the same or similar aircraft type, and no Notices to Airmen (NOTAM) or other restrictions preclude such operations.
If problems have been reported for the same or similar type, treatment as Case I through III, as applicable above, may be appropriate.
Appendix 4 NOTE: Unless otherwise restricted by an operator or the responsible Flight Standards office, FGS operations “Not-for-Minima-Credit” may generally be conducted on any instrument landing system (ILS) runway that does not have a restricting note on the approach plate (e.g., Localizer (LOC) unusable for rollout, glideslope unusable below xxx feet above ground level (AGL)), and that has an adequate threshold crossing height (TCH) suitable for the aircraft type. If problems are noted in the operator’s evaluation, the operator should specify that FGS use should not be accomplished at that site to touchdown. This may be done through a flightcrew bulletin or equivalent.
Conversely, an operator may publish a list of runways approved for FGS use to touchdown, or through rollout.
Advisory Circular Feedback Form If you find an error in this AC, have recommendations for improving it, or have suggestions for new items/subjects to be added, you may let us know by contacting the Flight Technologies and Procedures Division at 9-AWA-AFS400-Coord@faa.gov or the Flight Standards Directives Management Officer at 9-AWA-AFS-140-Directives@faa.gov.
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