A Complete Manual for Conducting International Flight Operations
Cruise Establishment / Mach Number Technique
The concept of Mach number technique is discussed in detail in NAT Doc 007, ICAO Doc 4444, and ICAO Annex 2. However, the general concept is that a specific Mach number is requested or assigned which will enable controllers to maintain longitudinal separation of aircraft while outside radar control. Flight Crewmembers might be asking themselves, "If my aircraft is ADS-B do I still need to advise of speed changes?" The Answer is Yes. http://www.ifalpa.org/downloads/Level1/Safety% 20Bulletins /16SAB07%20-%20KZAK%20Oceanic%20ATC%20Operations.pdf
Mach Number Technique Key Elements
Aircraft clocks must be correct to provide accurate estimates.
Aircraft climbs must be conducted at the assigned Mach Number.
Mach number shall be maintained within 0.01 Mach at or above FL250 or 10 knots below FL250. ICAO Annex 2 specifies that True airspeed shall be manintained within 5 percent of that which is cleared or filed.
True Mach must be flown, as opposed to indicated Mach. (Some aircraft require a correction.)
Long range cruise is not to be filed for segments where Mach number technique is applied.
Should a speed reduction be required due to turbulence, the flight crew must request the speed change as soon as possible.
If the time estimate for the next applicable reporting point, flight information region boundary, or destination aerodrome, whichever comes first, is found to be in error in excess of 2 minutes (Ammend. 43, this is not reflected on the Atlantic Orientation chart) from that notified to air traffic services, or such other period of time as is prescribed by the appropriate ATS authority or on the basis of air navigation regional agreements, a revised estimated time shall be notified as soon as possible to the appropriate air traffic services unit.
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ER and Oceanic Procedures
SLOP- SLOP stands for Strategic Lateral Offset Procedure and is a commonly used technique to mitigate the risk of wake turbulence and collision hazard while flying on an oceanic routing. SLOP may be used at the pilot’s discretion without clearance from ATC. At this time SLOP will always be either 1NM or 2NM right of course. However, there has been discussion of allowing SLOP increments as low as 1/10 NM. This offset is applied in the OFFSET line of the FMS on the progress page.
If 2NM of SLOP is desired, the appropriate entry would be R2.0. The aircraft shall be carefully monitored to determine that it establishes the correct offset at 2NM from the track centerline. A couple of important notes about SLOP: although no clearance is required to initiate SLOP, the aircraft must be returned to the centerline of the airway at the oceanic exit point and the entry point. SLOP is not approved for all airspace and ACI crewmembers must determine the acceptability of the procedure prior to initiating. Guidance regarding SLOP procedures is covered in ICAO doc. 4444, amd 2, 16.
Current areas where SLOP is authorized are the following:
Africa, various locations (according to the Jeppesen Airways Manual / Air Traffic Control / State Rules and Procedures - Africa).
Australia administered OCA (according to Australian guidance in Jeppesen Pages).China, on routes A1, L642, M771, and N892 (according to China guidance in Jeppesen Pages).
New York, Oakland and Anchorage Oceanic FIRs (according to U.S. FAA guidance).
Oceanic airspace in the San Juan FIR (according to U.S. FAA guidance).
The entire North Atlantic Track Region (according to the North Atlantic Operations and Airspace Manual).
The Pacific (including the NOPAC, Central East Pacific (CEP) and Pacific Organized Track System (PACOTS)) (according to U.S. FAA guidance).
South Pacific airspaces (according to U.S. FAA guidance).
Distress terminology- ICAO procedures have distress signals that differ from those which most U.S. pilots are familiar. In ICAO airspace the terms used to express an emergency situation are “MAYDAY-MAYDAY” and “PAN-PAN”, repeated three times. When such distress calls are heard on frequency it is the responsibility of all pilots to minimize radio congestion and render aid to the emergency aircraft as appropriate. For additional information on contingency procedures ICAO Annex 10 Vol II, 188.8.131.52 shall be referenced.
MAYDAY-MAYDAY- A condition of distress, being threatened by serious and or imminent danger and requiring immediate assistance. An example requiring a MAYDAY call would be an emergency descent, smoke in the cockpit, engine failure, etc.
PAN-PAN- A condition of urgency which does not require immediate assistance. PAN-PAN may be appropriate when an immediate weather deviation is necessary or to advise of a threatening meteorological condition.
Journey Log/Navigation Log
HF Communication Basics- HF stands for High Frequency and it pertains to the long range communication system that is required to be operating on oceanic flights. The HF has the advantage of skywave propagation, which allows HF radio waves to be reflected off the ionosphere and back to the earth’s surface. This eliminates the need for repeaters as are required for VHF or UHF communications systems. HF systems have the following advantages over VHF systems:
Ability to make contacts over long distances and varied terrain without being limited to line of sight
Atmospheric moisture not absorbing the signals, thus eliminating the need for repeater stations to maintain useful signal strength
Physic obstructions, whether natural or man-made, not attenuating the signal as much as with VHF
Flutter, such as that which occasionally plagues the VHF frequencies is absent in HF
Unlike VHF a large number of frequencies is available (280,000)
Most long range aircraft have two HF systems which utilize a single antenna. There are many different HF installations, but they share similar functionality. Some of the common codes amongst HF systems are the following:
MAN- Manual mode- This in the normal position for operations, the display shall indicate MANUV indicating manual mode for upper sideband voice.
SBY- Standby mode
TST- Test mode, selects built-in test and performs an HF system diagnostic
SQL- Squelch adjustment, silences undesired background noise when voice communication is not present, SQL 0 will all transmission noise through.
DSBL- Disables the SQL circuit (squelch)
UV- Upper sideband voice
LV-Lower sideband voice
UD-Upper sideband data
LD- Lower sideband data
Prior to initiating an transmission on the HF, the frequency shall be entered and the microphone switch shall be depressed, at which time a loud single tone will become audible indicating that the HF antenna is being tuned to the appropriate frequency. Care must be exercised to ensure that both units are not tuned to the same frequency as damage may occur.
ACI Jet crewmembers shall review their individual HF manuals to determine proper HF usage. When selecting a frequency from a list of multiple frequencies a key rule of thumb is, the higher the sun is in the sky the higher the frequency that should be selected. At night, the lower the sun, the better the lower frequencies will function. This phenomenon is due to the sun ionizing particles in the ionosphere which thickens the ionosphere which in turn reflects higher frequencies more effectively.
Position Reporting- The days of position reporting are numbered as 80 percent of the aircraft in MNPS airspace now use CPDLC, but for flight crews who have done position reports throughout their career, they will probably be the first to say that there is an art to position reporting and someone with limited experience is readily apparent.
Radio operators will be listening for position reports over the HF. HF radios are notorious for their distortion. The distortion coupled with multiple aircraft transmitting at the same time, and a new pilot unfamiliar with position reporting procedures and etiquette creates an opportunity for error. Some of the most common errors that pilots make when first learning to give a position report are the following:
Using non-standard ICAO phraseology
Reading position reports too fast
Reading position elements out of order
Reading latitude and longitude in Airinc 424 format rather than longhand
Failing to cross check position read backs
Failing to question radio operators when in doubt of clearance
Not addressing the correct ATS control
When making the initial call for a position report the flight crew shall raise the ATS radio operator as follows:
“San Francisco radio, San Francisco radio, N74GG, Position on frequency 5574”
Key elements of this transmission are the name of the oceanic controller, repeated twice, the aircraft registration using the November callsign, Position, which implies the intent of the flight crew to relay a position report and gives the radio operator an opportunity to prepare to record the forthcoming position report and the frequency on which the flight crew is transmitting. Announcing the frequency helps the radio operator in optimizing the signal quality of the transmission and reception. At the end of the transmission the radio operator will state “N74GG go ahead with position report” or “November flight calling standby”
When giving a position report the order and phraseology is as follows:
“N74GG, position Dinty, 1200, flight level four zero zero, estimating Duets at 1230, Dadie next, Over”
ACI Jet pilots have a journey log that mimics the order of a position report to aide flight crewmembers.
For this position report, N74GG crossed Dinty at 1200Z at flight level 400 and is estimating to cross position Duets at 1230 and Dadie is the subsequent position after Duets. F/R implies fuel remaining, F/F implies fuel flow, F/U implies fuel used, Mach is the Mach speed filed, cleared and flown using Mach number technique, wind is the wind speed obtained from the FMS and MH is magnetic heading after centering the heading bug and would be used as a reference if all other navigation sources failed. For questions relating to position reports flight crewmembers shall reference ICAO Doc 4444, appendix 1, 1,1.
ETP Review and FMS ETP Entry- After ETP’s have been calculated using manual, online or 3rd party calculations the ETP’s shall be constantly evaluated for viability based on current/forecast weather and NOTAM’s. For ACI Jet crewmembers it is recommend that ETP alternates are always at or above alternate airport weather minimums, which entails adding 400’ and 1 mile to the MDA or DH for airports with one straight-in approach and adding 200’ and ½ mile to the highest MDA or DH and ½ mile visibility to the higher authorized landing minimum for airports with at least two operational navigational facilities, each providing straight-in approaches to different suitable runways. It is worth mentioning that in some cases the alternate minimums for airports with one navigational aid may be lower, and may be used.
The fuel for the ETP’s shall also be evaluated, in most cases the ETP fuel will meet or exceed the trip fuel plus reserve fuel. For example, on a flight from KSBP-PHOG the following fuel and ETP summary is calculated.
The above is the fuel required for the flight, which does not take into fuel required to reach ETP airports from the ETP point. In the above example, if the aircraft departs with 20,000 lbs of fuel the fuel required to reach the destination is 13,828 lbs. reserve fuel is calculated as 4,000 lbs. so additional fuel remaining is 1768 lbs. In looking at the ETP summary, usually the pressurization ETP will be the most limiting and will have the highest fuel required.
In the ETP summary above the fuel required to reach the ETP waypoint and return or continue requires (8,063+9,770) 17,833 lbs. If the aircraft departs with 20,000 lbs of fuel, that will leave a reserve of 1,767 lbs of reserve after taxi fuel.
As seen in this example the total trip fuel with reserve is 17828 lbs. and the ETP depressurization fuel required is 17,833 without reserve. It is therefore recommended practice that ACI Jet crewmembers carry enough fuel to meet the greater of either the trip fuel plus reserve or the ETP fuel plus a marginal reserve. It is the pilots discretion as to what “marginal reserve” they choose to apply as this is not regulatory in nature, but the reserve shall consider the availability and weather at alternates, instrument approach procedures, NOTAMS, runway lengths, etc.
When evaluating the reserve fuel required for the ETP waypoints there are several important factors to note. Most 3rd party flight planners will instantly transport the aircraft from cruise altitude to the drift-down altitude or depressurization altitude. What this means to a pilot is the fuel saved during the drift-down procedure or emergency descent will provide additional fuel over the fuel calculation indicated in the 3rd party flightplan. It is important to know how your flight planning system will calculates fuel in the event of a drift-down or emergency descent. It is also important to note that the depressurization will usually be the most limiting of the three ETP calculations.
Oceanic Emergency Duties and responsibilities
Noting Time and Positions
Verifying Driftdown Speed and Performance
Aircraft lighting configuration
Gross Navigation Error Check- A gross navigational error check is to be performed 10 minutes after crossing a waypoint. The gross navigational error check is a method used to determine that the aircraft is established on the route that it was cleared and enables the flight crew to discover navigational discrepancies prior to a gross navigational error occurring. For ACI Jet pilots it is recommended that flight crews operate with a waypoint list presented on one of the MFD’s or EICAS screens as an additional means of situational awareness.
In the example above it is very easy to determine that the aircraft is currently flying the leg between BARAZ and BILLO and is presently located at North 32.10.6 latitude, West 139.00.2 longitude. For recording a 10 minute GNE plot, the pilot simply records the PPOS 10 minutes after crossing a waypoint and plots the position on a plotting chart. The position should along the course line provided the aircraft is on course and the aircraft’s route has been plotted correctly.
Mach Number technique- Mach number technique is a procedure designed to maintain separation in non-radar, class II navigation. M ach number technique is based on true Mach. For all ACI Jet aircraft, True Mach will be reflected on the PFD as opposed to older aircraft where an adjustment may be required to determine true Mach number.
Longitudinal separation in the North Atlantic may be as low as 5 minutes for CPDLC ADS-C aircraft, normally 10 minutes for other aircraft. In a hypothetical scenario assume that two aircraft are flying the same track between the same two waypoints, but are separated by 5 minutes. The ACI Jet crew recognizes winds are stronger than forecast and the aircraft will reach its next reporting point 4 minutes later than expected. The crew, in an attempt to make up the 4 minutes decides they will accelerate the aircraft from Mach .80 to Mach .85 in order to be within 3 minutes of their next waypoint ETA.
Meanwhile the Hawaiian Airlines 767 which is in the lead also encounters the forecast wind. The Hawaiian aircraft also realizes they will be 4 minutes late arriving at the next reporting, but rather than increasing speed they advise that they have a new estimate for the next reporting point and maintain the current Mach speed. Which aircraft is correct in this scenario? Will a loss of separation occur? The answer is the Hawaiian aircraft is correct to provide a revised estimate and maintain the assigned Mach, eventually loss of separation will occur as long as the wind is stronger than forecast and the ACI Jet aircraft will be responsible for the loss of separation.
If an ACI Jet is assigned a climb while oceanic should the crew maintain the filed Mach.80 or should they use the standard climb profile and climb at Mach .75? The answer is that the controlling agency expects the aircraft to climb at the assigned Mach of .80. If the aircraft is not capable of climbing at that speed a revised estimate must be provided to the controlling agency or the climb shall not be accepted.
ISA temperature monitoring- While in cruise, particularly on routings that take the aircraft to Northern Latitudes, or when evaluating step climbs it is important to monitor ISA temperatures. As mentioned earlier temperatures may be significantly above ISA at Northern Latitudes. This is due to the tropopause being lower (altitude) the closer you get to the earth’s poles. The tropopause is lower because it receives less radiant heat from the sun and therefore less convection occurs. In the below example the ISA deviation jumps significantly between ETP 1 and 6430N. As a crewmember being aware of the forecast jump in ISA temperatures is essential because it is possible that crewmembers may decide to climb the aircraft prematurely and when the ISA deviation spikes aircraft limitations may be exceeded or the aircraft may not be capable of maintaining the given altitude and airspeed.
Fuel/Oil/Hydraulic/Temperature Monitoring- Prior to coasting out ACI Jet crewmembers shall evaluate aircraft system functionality and performance.
For Gulfstream type aircraft the hydraulic systems are continually pressurized at 3,000 psi and considering that the flight controls are manipulated using hydraulic pressure it is worthwhile evaluating the system functionality and fluid level prior to entering an isolated flight regime. For the G-IV the appropriate fluid level in flight would indicate that the combined fluid level is half-full and the flight side hydraulic system is full.
For flight crews unfamiliar with the hydraulic levels in flight this hydraulic indication may seem unusually low, but for this aircraft is appropriate. Knowing appropriate indications make it easy for crewmembers to identify hydraulic leaks or component failures before they become critical issues. Hydraulic systems on the Gulfstream are also dependent on heat exchangers which are located in the fuel tanks. Should a failure of the heat exchanger occur the hydraulic temperatures would rise and potentially cause failure of the system.
It is also advisable for ACI Jet crewmembers to monitor fuel and oil temperatures while in flight. All ACI Jet aircraft have fuel/oil heat exchangers, and provided the system is operating properly the fuel will be warmed and the oil will be cooled. ACI Jet crewmembers shall have a general awareness of what fuel and oil temperatures are considered normal at altitude and shall monitor the fuel and oil temperatures for any trend that would indicate a failure of a system component. ACI Jet crewmembers shall also consider the impact of CAS messages relating to fuel or oil systems such as oil/fuel bypass prior to coasting out and while oceanic.
Fuel Accuracy and availability Check
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