Chap 2 Page 2-7
g. Missed Approach Construction.
(1) Chart the following missed approach instructions for the Delta 30° OSAP:
“Climb to 900 via the ∆ 30° heading, then climbing turn to the MEA, direct to the approach target within 10 NM and hold, or as directed by ATC.”
(2) Chart the following missed approach instructions for the parallel offset OSAP:
“Climb to 900 via the offset course, then climbing turn to the MEA, direct to the approach target within 10 NM and hold, or as directed by ATC.”
h. Missed Approach Holding. Chart the following holding instructions: “Hold over the approach target on the inbound course, 3 NM legs, maintain the MEA, or as directed by ATC.”
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2-8. OPERATIONAL APPLICATIONS.
a. Approaches consist of two types of procedures: Delta 30° and parallel offset OSAP. The Delta 30° OSAP procedure is preferred. A parallel offset OSAP may be used when obstructions do not allow for a Delta 30° OSAP.
b. Procedures and guidelines common to both types of procedures are as follows:
(1) Minimum Equipment Lists (MEL) must be modified to account for the effect of inoperative equipment on OSAP operations.
(2) Flight crews are provided with current observed coordinates for locations that are designated as landing sites. Before departure, the flight crew enters the observed landing site coordinates into the GPS or LORAN C receiver flight plan. This action designates the landing site as a "waypoint."
(3) Flight crews should use detailed procedures to ensure clearly defined crew duties for two-pilot operations. GPS or LORAN C is used for course guidance, and airborne radar in the mapping mode is used for obstruction identification and avoidance.
(4) Accuracy of completing an OSAP using LORAN C depends upon the crew’s ability to determine and select chain combinations and to use precise, up-to-date, coordinate data. Each operator develops a system for providing precise chain determination capabilities and both current and accurate observed coordinates. Approval of this system will be a part of the operator's OSAP authorization.
(5) OSAP’s are applicable only to helicopter operations to and from offshore platforms, rigs, or ships, and are not to be used less than 5 NM from land.
(6) Throughout this procedure, the airborne radar antenna sweep must not be less than 120°.
Less than a 120° antenna sweep will limit the radar operator’s ability to accurately observe and locate obstructions. Smaller sweep angles increase the possibility of premature loss of peripheral radar targets.
c. En Route and Intermediate.
(1) Flight from the last fix (or en route grid waypoint in the Gulf of Mexico) on the airway or route segment to the intermediate fix (IF) along a VORTAC or RNAV routing does not require modification to accommodate an individual OSAP. Procedures unique to an OSAP begin at the IF. The IF segment can begin over the approach target or on an arc.
(2) A descent below the MEA is not authorized at any point in the OSAP until the helicopter has departed the last en route fix and is offshore (see figure 2-2).
(3) The route entry into the final segment may be flown with a teardrop 7 NM procedure turn.
The procedure turn must remain within 10 NM of the approach target. A 7 NM arc entry to the final segment and a fix established at 7 NM from the approach target on the final course for direct routing to the turn on to the final course are also options (see figure 2-2).
(4) A CDI Sensitivity of 1.0 NM or less is set when departing the last en route fix.
Chap 2 Page 2-9
(5) During all phases of the en route and intermediate segments, the flight crew monitors the airborne radar and GPS or LORAN C systems to determine reliability and operational correctness.
d. Final approach:
(1) For radar detection and avoidance of obstructions, the final approach course is flown into the wind within 10° of the wind direction, and with no more than a 10° crosswind correction angle. This course is flown to the Delta change point for the Delta 30° OSAP and to the MAP for the parallel offset OSAP. After turning to the final course, a descent is made to no lower than 900 ft MSL prior to reaching the FAP. The crew establishes the FAP at not less than 5 NM from the approach target. At the FAP a descent is made to no lower than 500 ft MSL prior to reaching the DPA. The crew establishes the DPA at not less than 2 NM from the approach target. At the DPA, the crew confirms the final approach course is clear laterally of all obstacles by at least 0.5 NM before a descent is made to the MDA. If lateral separation is not assured by 0.5 NM, a missed approach is initiated. For the Delta 30° OSAP, a 30° turn is made at 1.1 NM from the approach target to the clear area either to the left or right of the approach target. The Delta 30° course is determined by adding 30° to or subtracting 30° from the inbound heading (see figure 2-3).
(2) During the final approach, if the GPS or LORAN C system and airborne radar display difference exceeds ±0.2 NM in range or azimuth, or the approach target is lost from the airborne radar display for one full sweep, an immediate missed approach must be made.
(3) The following procedures are required for the Delta 30° OSAP (see figure 2-3).
(a) The DPA is established after the FAP but not less than 2 NM from the landing site depending on obstacles within 0.5 NM of the final approach course.
(b) The Delta 30° heading is made either to the right or left of the straight-in portion of the inbound course depending on the clear area determined by the radar operator. The Delta 30° heading is maintained until the MAP if visual reference is not established with the landing site.
(c) Between the FAP and the MAP, the maximum ground speed is 70 knots.
(d) While on the Delta 30° heading and prior to the MAP, when visual reference with the landing site is established, the pilot proceeds visually to the landing area. If visual reference with the landing site is not established prior to the MAP and the pilot cannot proceed visually to the landing area, a missed approach is executed (see figure 2-3).
Page 2-10 Chap 2
(4) The following procedures are required for the parallel offset OSAP (see figure 2-4).
(a) Departing the FAP inbound, either a left or right turn is made to a heading that is established from the FAP on the 0.5 NM parallel offset inbound course.
(b) The direction of turn is selected based on the clear area determined by the radar operator.
Chap 2 Page 2-11
(c) The DPA is established after the FAP but not less than 2 NM from the landing site depending on obstacles within 0.5 NM of the offset course. This depends on the radar return of obstacles within the final area. The helicopter must be established on the parallel offset course prior to the DPA.
(d) Between the FAP and the MAP the maximum ground speed is 70 knots.
(e) After passing the DPA, a descent is made to the MDA on the parallel offset course.
The parallel offset course is maintained until the MAP or visual reference is made with the landing site.
(f) A turn is made to the landing site after visual reference is established.
(g) If visual reference with the landing site is not established prior to the MAP and the pilot cannot proceed visually to the landing site, a missed approach is executed (see figure 2-4).
Page 2-12 Chap 2
(5) Procedures and guidelines common to the Delta 30° and parallel offset OSAP’s are as follows:
(a) When using LORAN C to avoid adversely affecting updating capabilities, the pilot should maintain a stabilized airspeed and make small heading changes using well coordinated turns.
(b) Consideration should be given to the location of the helicopter in relation to obstructions in the event of airborne radar failure.
(c) Before beginning descent at the DPA, the radar operator accomplishes the following:
1. Selects the lowest appropriate scale on the airborne radar display to assure maximum radar accuracy.
2. Crosschecks the airborne radar and GPS or LORAN C to confirm agreement and accuracy.
3. Confirms a minimum lateral obstacle separation of 0.5 NM from the intended GPS or LORAN C course throughout the final and missed approach.
(6) Missed approach and holding procedures:
(a) Delta 30° OSAP MAP. The MAP is a point on the course established by the Delta 30° heading at 0.6 NM from the landing site.
(b) Parallel Offset OSAP MAP. The MAP on the parallel offset final approach is a point on the offset course at 0.7 NM from the landing site.
(c) The missed approach procedures for both approaches is a climb to 900 ft MSL via the Delta 30° heading or parallel offset course, depending on the type of approach that is made, then a climbing turn to the MEA direct to the approach target while remaining within 10 NM of the approach target and hold, or as directed by ATC (see figure 2-2).
(d) Holding after the missed approach: Holding is over the approach target fix on the missed approach inbound course with 3 NM legs, maintaining the MEA, or as directed by ATC (see figure 2-2).
(e) A missed approach is executed when any one of the following events occur:
1. Visual reference with the landing site is not made at the MAP.
2. Failure of the GPS or LORAN C.
3. Failure of the airborne radar.
4. The approach target is lost from the airborne radar display for one full sweep.
Chap 2 Page 2-13
5. When the radar operator determines the helicopter's track will not avoid all obstacles by at least 0.5 NM.
(f) When within close proximity of the MAP, if visual contact is not established, make only minor heading changes to avoid flight closer than 0.5 NM to any radar returns while following GPS or LORAN C course guidance during a missed approach.
(g) Lost communication procedure after the missed approach: Execute the published missed approach procedure and then proceed direct to the alternate at the MEA.
(7) Minimums:
(a) Takeoff Minimums:
1. The standard takeoff visibility for offshore landing sites is 1/2 SM.
2. When departing an offshore landing site, avoid all obstructions by at least 0.5 NM when below 900 ft MSL.
3. For departures from platforms that have no approved procedure, maintain VFR until able to climb through an obstacle clear area to the MEA.
(b) Landing Minimums:
1. RA 200 & 3/4 SM visibility.
2. 250 MSL & 3/4 SM visibility.
3. Requirements for charting the MDA:
• 200 ft RA: Radio altimeter must be operative.
• 250 ft MSL: Barometric altitude for use when radio altimeter is not available.
When the barometric altimeter setting is received from a source that is more than 5 NM from the landing site, increase the MDA by 5 ft for each mile in excess of 5 NM. The maximum distance for a remote altimeter setting source from a landing site is 75 NM.
(c) Alternate Minimums and Requirements: Standard alternate minimums of 800 ft ceiling and 2 SM visibility for nonprecision approaches apply for OSAP’s to be used as an alternate.
Requirements to establish an alternate are listed below:
Page 2-14 Chap 2
1. Approved source of weather observations and reports.
2. Two-way communications with aircraft making an approach.
3. Any required onshore alternate requires a standard or special instrument approach procedure other than GPS or LORAN C that is anticipated to be operational at the estimated time of arrival.
Chap 3 Page 3-1 CHAPTER 3. AIRBORNE RADAR APPROACHES
3-1. ARA SYSTEM COMPONENT REQUIREMENTS. (See appendixes 2 and 3 for sample LOA’s and OpsSpecs). This section applies to helicopter ARA procedures for offshore landing sites conducted under IFR. The procedures criteria in this AC apply to airborne weather radar with mapping mode that has a demonstrated navigational capability acceptable to the Administrator for ARA procedures.
The airborne weather radar systems that have proved suitable for use as primary instrument approach aids are short-range pulse radars, manufactured and approved for the purpose of weather avoidance rather than navigation. Minimum system components for procedures based on airborne radar only (with or without beacon capability) are as follows:
a. Airborne Radar. Radar system minimum requirements:
(1) Stabilized 120°/ 60° sector scanning antenna with scan rates of no less than 12 per minute and 24 per minute respectively.
(2) Adjustable light display.
(3) Alphanumeric display for selected ranges and azimuth markers; however, alphanumeric display for selected ranges is not required when:
(a) A positive means for determining selected scale is available, and
(b) The radar operator is appropriately trained.
(4) The indicated range error should not exceed ± 0.2 NM for display ranges of 5 NM or less.
(5) The lowest selectable range display should be at least 2.5 NM with a range mark display of 0.5 NM to meet the authorized landing minimums. Equipment that provides a lowest range display of 5 NM with a range mark display of 1 NM may be used, but a 1/4 NM penalty is imposed on established visibility minimums.
(6) Tilt control ±± 15°.
(7) Test pattern.
(8) Primary mode (beacon mode may be necessary for cluster approach).
(9) Fault monitor or self-test.
(10) An operational course bearing cursor that provides course guidance is required to fly cluster approaches below obstacles.
(11) With zero pitch and roll signals applied to the antenna scanner representing level flight attitude, the indicator update strobe line should indicate the antenna beam center to within ± 3° at any scan angle.
Page 3-2 Chap 3 NOTE: A radio altimeter must be installed and operational before descent to the RA MDA is authorized.
b. Radio Altimeter. The radio altimeter must meet the requirements of TSO C87.
c. Offshore Heliport Facilities.
When required to ensure positive identification of targets, a radar transponder beacon should be evaluated during the approval process.
3-2. AIRWORTHINESS. As a minimum, ARA systems shall meet the airworthiness requirements of TSO C63 or C102. Installation of an ARA system for IFR use is a major change in type design, and the provisions of 14 CFR Parts 21.97, 43.5, and 43.7 apply. System installation requirements are:
a. System controls and data displays must be conveniently accessible and visible to radar operators at their duty stations. The system controls should be protected against inadvertent operation.
b. Electrical power for the system should be obtained from a bus that provides maximum reliability for electrical power without jeopardizing other essential or emergency loads.
c. The ARA system should not be a source of objectionable electromagnetic interference and shall not be adversely affected by electromagnetic interference from other helicopter equipment.
d. Any probable malfunction of the ARA system should not adversely affect the normal operation of other systems or equipment installed in the helicopter.
e. System performance should not be adversely affected by helicopter attitude, altitude, or main rotor RPM normally encountered in flight operations.
3-3. MAINTENANCE.
a. Airborne weather radar and radio altimeter maintenance shall be performed in accordance with 14 CFR Part 43 and the manufacturer's instructions or in accordance with a manual under an FAA-approved maintenance program. Records of maintenance should be entered in the helicopter maintenance records required by 14 CFR Part 43.9 or in the records required by the operator's approved maintenance program. Following repair or alteration, the system should be checked by appropriate ground and flight evaluations before predicating any operation on its use. Compatibility of replacement parts and components should be assured. Ground-based radar beacon or reflector maintenance will be performed in accordance with the manufacturer's instructions and must be under an FAA-approved maintenance program.
b. Each operator’s maintenance program must be approved by the FSDO issuing the ARA authorization before any ARA operations in instrument IMC may be conducted.
3-4. INSPECTION AND TEST PROCEDURES. IFR ARA systems that are not under an FAA-approved maintenance program should be maintained under inspection and test procedures that ensure the equipment continues to be capable of navigation with at least the degree of accuracy required for original approval. These procedures should include methods for analyzing malfunctions and defects to
Chap 3 Page 3-3 determine that established inspections and tests reasonably assure maintenance of equipment accuracy.
Procedures and intervals for tests and inspections should be adjusted in accordance with results of the analysis. In addition to the equipment manufacturer's recommendations, the following test and inspections should be included:
a. A visual inspection to determine condition and security of equipment mounting, electrical wiring and connectors, radome, antennas and cables, wave guide and couplings, indicator mounts, knobs, etc.
b. A functional test of the airborne weather radar mapping mode and radio altimeter to determine operating conditions. Tests should be performed in accordance with appropriate manufacturer's procedures.
c. Other appropriate tests and inspections to determine whether the complete system is operating properly.
3-5. APPROVED WEATHER OBSERVATION AND REPORTING REQUIREMENTS. Refer to FAA Order 8400.10, Volume 4, Aircraft Equipment and Operational Authorizations, Chapter 7. Rotorcraft Authorizations and Limitations, Section 1. IFR Offshore Operations, and Title 14 CFR Part 91, Subpart B - Flight Rules/General.
3-6. TRAINING PROGRAM AND FLIGHT CREWMEMBER EXPERIENCE. Before conducting ARA operations in IMC, each flight crewmember should have:
a. Ten hours of flight crew experience operating IFR (at either crew station) in the offshore route structure.
b. A minimum of ten ARA’s and at least four from each crewmember position. This may be reduced by the POI for the certificate holder based on the flight crew experience and proficiency.
c. All training must be a matter of record.
d. After completing ARA training, each flight crewmember must pass an ARA flight proficiency check. They may then be authorized to use the ARA to 100 ft above the lowest established ceiling minimums and 1/2 SM above the lowest established visibility minimums. Each crewmember must then fly and record ten additional ARA’s before receiving authorization to conduct operations to the lowest established ceiling and visibility minimums required by the operator. The POI may reduce these requirements based on total crew experience provided the pilot-in-command meets all the conditions of this paragraph.
e. The flight proficiency check is an annual requirement.
f. Helicopter flight simulators specifically approved for ARA training by the National Flight Simulator Evaluation Team and the POI assigned to the operator may be used for any amount of required training.
g. Operators requesting authority to use ARA’s are required to satisfactorily train their flight crewmembers under an FAA-approved training program before beginning ARA operations. Operators
Page 3-4 Chap 3 should submit a proposed training program to the CHDO for approval. (See appendix 4 for sample training program.)
3-7. PROCEDURE DEVELOPMENT CRITERIA. Approach chart examples are in appendix 5, figures 5-3 and 5-4. A certificated air carrier submits a written request with the proposed chart through the CHDO POI to the FSDO having jurisdiction over the area of intended operation. All other operators submit requests directly to the FSDO having jurisdiction over the area of intended operation. The FSDO having jurisdiction forwards the procedure to the regional AWO program manager for approval of the procedure and coordination with air traffic elements and the regional Flight Procedures Office (FPO).
Coordination with the FPO is required when expenses are incurred by the FAA for the development and/or flight check of a procedure. (See appendix 1, Request For Approval of OSAP, ARA, or HEDA Procedures.) The following note is charted in the plan view of the procedure:
“SPECIAL AUTHORIZATION REQUIRED.
WX RADAR IN MAPPING MODE REQUIRED.”
a. Procedure Identification. The procedure is identified as “Copter ARA” with the name of the cluster or rig, e.g. “WINTR 120.” If the procedure requires beacon capability, the procedure will be annotated “Beacon Required.” A note specifying the platform containing the beacon is printed on the plan view of the chart, e.g. “Beacon on Platform 1.” (See appendix 5, figure 5-4.)
b. Procedure Construction. For ARA procedures, obstructions 50 ft or higher above the surface are considered obstacles. Where landing sites or approach targets are less than 100 ft above the surface, all obstacles within 50 ft of the site’s height shall be charted. An ARA procedure to an offshore site has two areas, the intermediate area and the final approach area. Missed approach airspace is contained within the two areas (see figures 2-4 and 3-1). Determine whether the procedure is for a single landing site or for a cluster of landing sites. Identify the final approach area. Connect it to the en route structure by an overlying intermediate area that is used for transition. The procedure shall also contain the land side navigation facility, the route designation, and the location of the destination site or landing site cluster. For en route construction, apply paragraph 2-7a of this AC. The ARA chart contains a table to determine the time required to fly an outbound 4 NM leg for a teardrop procedure turn. The intermediate and final segment construction is described in paragraph 3-7c. Sample ARA approach charts are contained in appendix 5, figures 5-3 and 5-4.
c. Single Approach Target Procedure Construction. This procedure provides for an into-the-wind final descent to the landing site from any direction, depending on the surface wind reported in the approach target area and the operating procedures selected by the flight crew (see figure 3-1).
(1) The IF is located on the en route course centerline not less than 10 NM or more than 20 NM from the approach target.
(2) The required obstacle clearance (ROC) for the intermediate approach area is 500 ft above the highest known obstacle in the intermediate approach area until arrival at the FAP inbound. The lowest charted minimum altitude is 600 ft MSL and is charted as follows:
“600 ft MSL or no lower than the barometric MDA adjusted for RASS.”
This note is required to assure that the FAP altitude is no lower than the MDA adjusted for the RASS.