AC 91-70A

Historical

Advisory circular · Oceanic and International Operations

A newer version is currentThis is a historical version. AC 91-70D CHG 1 is the version in force, approved October 19, 2026.
Approved
August 12, 2010
Last reviewed
August 1, 2024
Cancels
AC91-70
Cancelled by
AC91-70B
Family
AC 91-70 · 7 versions
Revision
A
14 CFR parts
91, 119, 121

Guidance, not mandatory unless a rule or AD requires it. DRS record last changed November 21, 2025.

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• The seasonal meteorological conditions.

• The meteorological, communication, and air traffic facilities, services, and procedures.

• The Search and Rescue (SAR) procedures.

• The navigational facilities and procedures, including any long-range navigation system (LRNS) procedures associated with the planned route.

b. Applicable Procedures. The PIC must also demonstrate an adequate knowledge of procedures applicable to flight paths over heavily populated areas and areas of high air traffic density; obstructions; physical layout; lighting; approach aids and arrival, departure, holding and instrument approach procedures (IAP); and applicable operating minimums.

c. Approaching Airports. The PIC will have made an actual approach into each airport of landing on the route, accompanied by a pilot qualified for that aircraft, as a member of the flightcrew or as an observer on the flight deck, unless:

• The approach to the airport is not over difficult terrain, the landing approach aids available are similar to those that the pilot has knowledge of, a margin approved by the Administrator is added to the normal operating minimums, or there is reasonable certainty that they can make a specific approach in visual meteorological conditions (VMC).

• The PIC can make the descent from the initial approach altitude in day VMC.

• The operator qualifies the PIC to land at the airport concerned by means of an adequate pictorial presentation.

• The airport concerned is adjacent to another airport at which the PIC has the qualifications to land.

12-3. TRAINING CONSIDERATIONS.

a. Receiving Approval. Crews conducting oceanic flights will receive training approved by the Administrator. Air carrier’s training programs will receive approval in conjunction with their certification and subsequent issuance of operations specification (OpSpec). General aviation aircraft desiring to fly in special use airspace will receive approval through the issuance of letter of authorization (LOA) crew qualifications for one of the following may satisfy the issuance of an LOA:

• Completing an operator’s oceanic operations training program.

• Completing a commercial oceanic operations training program.

• Submitting military training records indicating prior oceanic operations experience.

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• Using other methods indicating to the operator that the crew can safely conduct oceanic operations. (Examples could include written testing, oral testing, or evidence of prior experience.)

b. Qualifications for Oceanic Operations. To consider a crew qualified for oceanic operations, crewmembers must be knowledgeable in the following subject areas:

• ICAO operational rules and regulations.

• ICAO measurement standards.

• Use of oceanic flight planning charts.

• Sources and content of international flight publications.

• Itinerary planning and overflight clearances.

• Federal Aviation Administration (FAA) international flight plan, ICAO flight plan, and flight log preparation.

• Route planning within the special use airspace where they conduct flights including Reduced Vertical Separation Minimum (RVSM) and Required Navigation Performance (RNP) requirements.

• En route and terminal procedures – different from U.S. procedures.

• Long range, air-to-ground communication procedures including all data link and satellite communication (SATCOM) Voice operations.

• Structure of the special use airspace where they conduct the flights.

• Air traffic clearances.

• International meteorology, including significant weather, charts, prognostic weather charts, tropopause prognostic charts, and terminal area forecasts (TAF).

• Specific en route navigation procedures for each type of navigation equipment required for use in the special use airspace.

• Emergency procedures, including required emergency equipment, SAR techniques, navigation equipment failure techniques, and communication equipment failure techniques.

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CHAPTER 13. GENERAL AVIATION SHORT-RANGE AIRCRAFT OCEANIC

OPERATIONS

13-1. INTRODUCTION. This chapter provides guidance to the general aviation pilot who is flying a light, general aviation aircraft in oceanic operations, and specifically addresses aircraft with a relatively short range that cannot transverse an ocean without intermediate fuel stops. You should read the information contained in this chapter in detail. It is important to note that this chapter includes International Civil Aviation Organization (ICAO) rules and Canadian departure requirements for transoceanic flights. These requirements become regulatory to U.S. pilots by virtue of the content of Title 14 of the Code of Federal Regulations (14 CFR) part 91, § 91.703.

Most short-range aircraft crossing the North Atlantic (NAT) will, out of necessity, make a Canadian departure. These aircraft are bound by Canadian regulations in addition to U.S.

regulations and ICAO rules. Although emphasis in this chapter is on NAT flights by short-range aircraft, the majority of the information is pertinent to all oceanic operations by short-range aircraft with the exception of operations in minimum navigation performance specifications (MNPS) airspace.

13-2. ICAO GUIDANCE. Noncompliance with basic requirements for navigation and communication equipment needed for oceanic flights or flights over remote areas caused a number of incidents that have occurred with NAT international general aviation (IGA) flights.

Most of the incidents were potentially hazardous to the aircraft occupants and to aircrew members called upon to conduct the searches. Some of the incidents resulted in needless and expensive alert activities on the part of the air traffic control (ATC), communicators, and controllers in search activities by rescue facilities. The incidents generally involved flights that were considerably off-course or had not made the required position reports. This chapter provides information for flight planning and operation of General Aviation (GA) flights across the NAT, in particular those operations carried out by light aircraft. GA pilots planning to cross the Atlantic at altitudes between flight level (FL) 275 and FL 400 (the altitude limits of MNPS airspace) must obtain a letter of authorization (LOA) for part 91 operations or must receive operations specification (OpSpec) approval if conducting an air carrier operation.

13-3. THE NAT ENVIRONMENT. The climate affecting NAT flight operations is demanding throughout the year as it’s likely that operators will encounter storms or other adverse weather during any season. It is probable that any transatlantic flight will encounter adverse weather on at least a portion of the flight. The scarcity of alternate airports available to transatlantic flights requires consideration of all significant weather systems along the route during the flight planning phase. Flights at higher NAT FLs (FL 275 – FL 400) require the Federal Aviation Administration (FAA) to authorize them for flights in the NAT/MNPS airspace. Navigation systems available to pilots include global positioning system (GPS).

However, a single Global Navigation Satellite System (GNSS) system or sensor that meets the requirements specified in Technical Standard Order (TSO) C-129 or C-129A may receive approval as a means in conjunction with VHF Omnidirectional Range (VOR), distance measuring equipment (DME), and non-directional radio beacons (NDB) of oceanic navigation in NAT/MNPS airspace. We highly recommend an inertial navigation system (INS)/inertial reference system (IRS) as a self-contained navigation system. Therefore, it is extremely important that pilots understand the capabilities of their equipment and ensure that accurate navigation facilities exist to support their equipment throughout all of the proposed routes of Par 13-1 Page 143

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Page 144 Par 13-3 flight. Several high-power NDBs located in the NAT region are useful to automatic direction finder (ADF)-equipped aircraft. Transmitters on adjacent frequencies do not monitor some of these stations, including commercial band transmitters, for outages or interference as atmospheric conditions without warning may severely affect the stations.

a. VHF Communications. Very high frequency (VHF) communications coverage extends to line-of-sight distance from facilities in Canada, Iceland, Greenland, the Azores and coastal Europe. Use of a remote facility in southern Greenland extends Canadian VHF coverage. High frequency (HF) communications are available throughout the NAT region for ATC purposes.

Use of HF by pilots on IGA flights permits proper monitoring of the flight’s progress.

HF-equipped flights should be able to receive meteorological information for aircraft in flight (VOLMET) broadcasts, including significant meteorological information (SIGMET) and continuous meteorological updates at major terminals in Europe and North America.

b. Search and Rescue (SAR). SAR vessels and aircraft are at some locations in the NAT region, but SAR aircraft may not always be available. The availability of SAR vessels may depend on the disposition of a nation’s civil emergency fleet. A nation’s fishing fleet often composes these fleets, and their proximity may depend on the current fishing situation.

13-4. PILOT QUALIFICATION REQUIREMENTS.

a. Minimum Pilot Qualification. The minimum pilot qualification for any flight across the NAT is a private pilot certificate. Operating above FL 60 (6,000 feet MSL), the pilot in command (PIC) must hold an instrument rating. The demanding NAT operational environment requires that the PIC have the following flight experience in addition to cross-country flight time:

• The PIC must meet the “recency of experience” requirements stipulated in part 91.

• The PIC must have adequate recent flight experience in the use of long-range navigation and communication equipment used. We highly recommend that pilots document the training they have received and their experience using this equipment prior to embarking on any oceanic flights. This documentation will be invaluable should the pilot file a navigation error report due to equipment difficulties that cause an error.

b. National Regulations. Pilots of U.S.-registered aircraft must comply with all applicable U.S. regulations, ICAO Annex 2, and the regulations of the states in which they overfly or land.

In the case where U.S.-regulations are more stringent than ICAO standards or vice versa, pilots are to adhere to the more stringent regulation or rule.

13-5. OCEANIC FLIGHT STANDARDS. ICAO member states have agreed that ICAO flight standards will be in effect for operations over the high seas. However, responsibility for enforcement of these standards rests with the State of Registry of the aircraft or the State of Registry of the operator. ICAO Annex 2 contains ICAO flight standards. ICAO Document 7030, current edition, covers procedural aspects. Under § 91.703, U.S.-registered aircraft must comply with ICAO Annex 2. U.S.-registered aircraft planning to operate in MNPS airspace must also comply with § 91.705. Paraphrased below are some of the more significant ICAO standards:

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• All flights that cross an international border must file a flight plan.

• All flights will file an instrument flight rules (IFR) flight plan when intending to fly in NAT airspace at FL 60 and above in New York, Gander, Shanwick, Santa Maria and Reykjavik Oceanic flight information regions (FIR). In addition, IFR flight plans must file for the Bodo Oceanic FIR beyond 100 NM from the shoreline; and at FL 200 and above in the Sondrestrom FIR.

• While en route, report all changes to IFR flight plans as soon as practicable to the appropriate Air Traffic Service (ATS) as prescribed.

• Send an arrival report to the appropriate ATS unit. When you cannot close the flight plan by means of the aircraft radio, send either a telephone or telegraphic message.

Failure to close flight plans may result in a needless search operation.

13-6. OPERATION OF AIRCRAFT. ICAO member states have agreed that aircraft with their registration mark will comply with the standards concerning the operation of aircraft contained in ICAO Annex 6, as a minimum. Some of the more pertinent standards are paraphrased below:

• Before commencing flight, the pilot must ensure that the aircraft is airworthy, duly registered, and that appropriate certificates are onboard. Pilots flying U.S.-registered aircraft should be especially concerned with the “duly registered” aspects of this section. Title 14 CFR part 47, §§ 47.3 through 47.11 are specific regulations relative to the legality of U.S.-registered aircraft.

• Aircraft instruments and equipment must be appropriate for the operation, considering expected flight conditions. Chapter 10 provides details of required instruments and equipment in addition to the information provided below.

• The PIC must obtain meteorological information relevant to the flight and evaluate it with regard to the planned route, destination, and alternative courses of action.

• Maps and charts that are current, suitable for the flight, and include alternative routes must be available on the aircraft.

• The PIC obtains SAR information, including location of facilities and procedures.

• The PIC should check the Notices to Airmen (NOTAM) prior to departure to ascertain the status of radio Navigational Aids (NAVAID) and airport restrictions.

• Night operations can present additional problems that the PIC must consider, such as increased navigation difficulties, fatigue, more demanding pilot skills, and other factors.

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• The PIC should check the Aeronautical Information Publication (AIP) of states where landings will be made or for states that will be overflown prior to departure. This advisory circular (AC) provides the necessary operational information derived from the AIPs, particularly with respect to the requirements for the carriage of survival equipment.

13-7. EQUIPMENT.

a. Emergency Equipment Requirements. Single-engine aircraft will carry life rafts when operating more than 100 NM from shore and multiengine aircraft will carry them when operating more than 200 NM from shore. These life rafts will contain at least the following:

• Pyrotechnic distress signals.

• Food and water.

• A VHF survival radio.

b. Navigation Equipment. On transatlantic flights, aircraft will have navigation equipment equipped that will enable it to proceed in the following capacities:

• In accordance with the flight plan.

• In accordance with the requirements of the ATSs.

• In accordance with MNPS requirements when operating in that airspace.

c. Communication Equipment. In controlled airspace, flights must be able to conduct two-way radio communication on required frequencies. Use of emergency frequencies as a planned operation is in conflict with this rule. The VHF emergency frequency 121.5 megahertz (MHz) does not have authorization for routine use. The frequency 123.45 MHz is the air-to-air communication frequency in the NAT region. In the Gander, Shanwick, Santa Maria, Reykjavik, Sondrestrom and New York FIRs, HF radios are to contact ATS units when beyond the range of VHF. Subject to prior arrangement, you may make VHF-only flights via Canada, Greenland, Iceland, and Europe, provided you avoid the Shanwick FIR. We recommend pilots planning these types of flights to obtain and study the individual AIPs pertaining to their route of flight.

13-8. SPECIAL REQUIREMENTS FOR FLIGHTS TRANSITING GREENLAND. The elevation of the highest point in Greenland is 13,120 feet mean sea level (MSL), and the general elevation of the icecap is 9,000 feet MSL. Knowledge of the high altitudes in Greenland need to be taken into account in the event of pressurization and emergency descent situations. Due to the low temperatures and high wind speeds, the lowest useable FL under certain conditions may be FL 235 near the highest point and FL 190 near the icecap. High-capacity cabin heating systems are necessary due to the very low in-flight temperatures usually encountered, even in summer.

Rapidly changing weather situations involving severe icing, severe turbulence, and heavy precipitation are common and require extra vigilance by pilots. The changes may be so rapid that they are difficult to forecast. An emergency locator transmitter (ELT) transmits Greenland due to Page 146 Par 13-6

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Par 13-8 Page 147 the very difficult terrain that hampers searches. The air navigation service provider (ANSP) monitors regulatory compliance and states will be informed of any infractions. Narsarsuaq Airport, Nuuk/Godthab Airport, Kulusuk Airport, and Ilulissat/Jakobshavn Airport at Constable Point provide airport flight information.

a. Airport Locations. The general locations of these airports are as follows:

• Narsarsuaq is on the southern tip of Greenland at the end of a fjord.

• Nuuk/Godthab is on the west coast of Greenland halfway between Narsarsuaq and Sondrestrom.

• Kulusuk is on the east coast of Greenland 343 NM northeast of Narsarsuaq.

• Ilulissat/Jakobshavn is on the west coast of Greenland 137 NM north of Sondrestrom.

b. Radio Equipment Requirements for Aircraft Operating Below or Above FL 195.

The Sondrestrom FIR below FL 195 only provides flight information service (FIS) and alerting service. IFR flights operating within the Sondrestrom FIR below FL 195 must have functional radio equipment capable of operating on the published HFs for Sondrestrom. Flights operating within the Sondrestrom FIR above FL 195 (that is, Reykjavik or Gander control areas (CTA)) and outside of VHF coverage of Iceland or Gander must have functional radio equipment capable of operating on the published HFs for Iceland/Gander.

13-9. SPECIAL REQUIREMENTS FOR FLIGHTS TRANSITING ICELAND. The general elevation of mountainous areas in Iceland is approximately 8,000 feet MSL. Due to the great difference in pressure and high wind speeds, the lowest useable FL may, under certain conditions, be FL 120.

a. Survival Equipment. Aircraft should be equipped with sufficient and appropriate arctic survival equipment. Aircraft operating in the oceanic sector of the Reykjavik FIR must maintain a continuous watch on the appropriate frequency of Iceland Radio. When operations take place outside of VHF coverage of the air-ground station, carriage of an HF transceiver operational on appropriate frequencies is mandatory. However, you may obtain prior approval for flight outside VHF coverage and without HF equipment. Flights operating under this special approval are responsible for obtaining similar approval for operating in the airspace of adjacent ATC units.

Flights between FL 80 and FL 195 on the route between Sondrestrom and Keflavik passing through 65° N. 30° W. and Kulusuk, and flights above FL 240 operating between the United Kingdom and Iceland routed at or north of 61° N. 10° W., have adequate VHF coverage and are exempt from HF requirements.

b. Navigation Equipment. The aircraft will carry navigation equipment adequate to navigate in accordance with the flight plan and ATC clearances onboard. Iceland requires Secondary Surveillance Radar (SSR) transponders with Mode 3/A and C. Pilots will operate SSR transponders continuously on Mode A, Code 2000, except that departing aircraft will retain the last assigned code for 30 minutes after entry into NAT oceanic airspace unless otherwise

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instructed by ATC. AIPs and NOTAM information are available on request at all Iceland airports of entry and from the Directorate of Civil Aviation Telegraph address:

CIVILAIR ICELAND Aeronautical Information Service TELEX: 2250 FALCON ISLAND Reykjavik Airport, Iceland AFTN: BICAYN 101 Reykjavik

13-10. ELT REQUIREMENT FOR TURBOJET-POWERED AIRCRAFT. Effective January 1, 2004, all U.S.-registered civil airplanes having a maximum payload of less than 18,000 pounds, including turbojet-powered aircraft, must have an ELT installed. You can find exceptions to this requirement in § 91.207.

a. ICAO Annex 6, Part II ELT Requirement. From January 1, 2005, all general aviation “aeroplanes” operated on “extended flights over water” and on flights over “designated land areas” (as defined in ICAO Annex 6, Part II) must have one automatic ELT that transmits on both 406 MHz and 121.5 MHz equipped.

b. ICAO Annex 6, Part I ELT Requirement. From January 1, 2005, all “aeroplanes” operating as “commercial air transport” on “long-range over-water flights” and (as defined in ICAO Annex 6, Part I) must have two ELTs, one of which is automatic, equipped. These ELTs must transmit on both 406 MHz and 121.5 MHz.

13-11. SPECIAL REQUIREMENTS FOR CANADIAN DEPARTURES. Canadian Air Regulation S.540 prohibits singleengine aircraft from transoceanic flight departing Canada unless the Minister grants the aircraft authorization to do so. This regulation also applies to multiengine aircraft that cannot maintain flight after failure of the critical engine. The PIC of a single-engine or multiengine aircraft must obtain authorization to commence a transatlantic flight from Canada after landing at Moncton or New Brunswick in Canada. The PIC will receive authorization when they meet the requirements that satisfy the Regional Director, Aviation Regulation, or a representative. At least 48 hours prior to landing at Moncton, the pilot should inform the Regional Director, Aviation Regulation, 95 Foundry Street, Moncton, New Brunswick, Canada, E1C 8K6, Telex 0142 666, of the intended transatlantic flight, stating date and time of arrival at Moncton, aircraft type, registration mark, and pilots’ and passengers’ names and addresses. Inspections are also possible at other regional offices in Montreal, Toronto, Winnipeg, Edmonton, and Vancouver. However, we request that you make the first contact with Moncton to coordinate the details of an alternate inspection site.

a. PIC Requirements for Examining Officer. At Moncton or the alternate inspection site, the PIC must satisfy an examining officer of the following:

• Certification as a pilot with a valid and current instrument rating.

• Knowledge of the meteorological, communication, ATC, and SAR facilities and procedures on the route flown.

• Knowledge of radio and other NAVAIDs, and the ability to use these aids en route.

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b. Preparation and Requirements for Authorized Routes. Authorized routes will be those that will provide a minimum of 3 hours fuel reserve at destination considering useable fuel, an appropriate flight manual fuel consumption and true airspeed (TAS) indication (documented or charted), and a ZERO wind component. The PIC must present a complete navigation log for the ocean crossing. The log must show 5° longitude checkpoints, tracks, variation, and distances with the capability to recalculate on the basis of the most recent forecast en route winds. In anticipation of equipment problems, pilots should make preparations to complete the flight using dead reckoning (DR) navigation techniques.

NOTE: Some experienced ferry pilots apply the forecast wind to each 5° longitude segment of track to the nearest 10°, then add 10 knots if a headwind or subtract 10 knots if a tailwind. Next they ensure that both wind direction and track are in magnetic units by applying variation to the true course. If the cross-track wind component is over 20 knots or the drift angle is over 10°, they wait for a better wind before departing. High speed, unforecasted winds can easily increase the flight time to the extent that a short-range aircraft cannot comply with the 3 hour fuel reserve regulation.

c. Inspection Documents. Upon arrival at the inspection site, the PIC will present the following documents for inspection:

• Certificate of Registration from the State of Registry. The State of Registry requires U.S.-registered aircraft to have a permanent registration. Temporary (pink slips) are not satisfactory for oceanic flights.

• Certificate of Airworthiness, Flight Permit, or Special Airworthiness Certificate.

• Certification and special conditions issued by the State of Registry to allow over gross weight operations, if applicable.

• Certification issued by the State of Registry for fuel tank modifications and/or the installation of temporary long-range tanks. For U.S.-registered aircraft, obtaining a completed FAA Form 337, Major Repair and Alteration (Airframe, Powerplant, Propeller, or Appliance), satisfies the certification requirements.

• Revised Weight and Balance (W&B) records in the case of aircraft modified to carry extra fuel.

NOTE: An export Certificate of Airworthiness does not constitute authority to operate an aircraft. One of the documents listed above must accompany it.

These documents are not available at Moncton, and Canadian authorities have no authority to issue these documents to U.S.-registered aircraft.

d. Aircraft Equipment Requirements.

(1) Sea Survival Equipment. Aircraft are required to carry the following sea survival equipment:

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• A readily accessible watertight immersion suit for each occupant, including undergarments which provide thermal protection.

• A readily accessible life jacket, complete with light, for each occupant.

• A readily accessible Type W, water-activated, self-buoyant, water-resistant ELT.

• A readily accessible life raft sufficient to accommodate all persons onboard the aircraft. Fit the life raft with the following items:

• Water, or a means of desalting or distilling saltwater, sufficient to provide at least one pint of water per person.

• A water bag.

• Water purification tablets.

• Food that is in the form of carbohydrates, has a caloric value of at least 500 calories per person, and is not subject to deterioration by heat or cold.

• Flares (at least three per life raft).

• Hole plugs.

• A bail bucket and sponge.

• A signal mirror.

• A whistle.

• A knife.

• A survival at-sea manual.

• Waterproof flashlights (minimum two per life raft).

• A first aid kit containing eye ointment, burn ointment, compresses, bandages, methiolate, and seasick pills.

• A dye marker.

(2) Polar Survival Equipment. You may store and carry the water and food in appropriate containers separate from the rafts if you can readily and quickly attach the containers to the raft. In addition to the items listed as “sea survival equipment” (above), aircraft will carry the following polar survival equipment for flights over Labrador, and for any flight routing north of Prins Christian Sund over Greenland:

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• A signaling sheet (minimum 1 x 1 meters = 3.28 feet x 3.28 feet) in a reflecting color.

• A magnetic compass.

• Winter sleeping bags in sufficient quantity to accommodate all persons carried.

• Matches in waterproof covers.

• A ball of string.

• A stove and supply of fuel or a self-contained means of providing heat for cooking and the accompanying mess kits.

• A snow saw.

• Candles or some other self-contained means of providing heat with a burning time of about 2 hours per person. The minimum candles carried onboard must not be less than 40 hours of burning time.

• Personal clothing suitable for the climatic conditions along the overflown route.

• A suitable instruction manual in polar survival techniques.

• Mosquito netting and insect repellant.

e. Instruments and Equipment in Serviceable Condition. Aircraft must have following instruments and equipment in serviceable condition equipped:

• An airspeed indicator and heated pitot head.

• A sensitive pressure altimeter.

• A direct reading magnetic compass calibrated within the preceding 30 days with the aircraft in the same configuration as for the intended transoceanic flight.

• A gyroscopic direction indicator or a gyromagnetic compass.

• A turn and bank indicator.

• A rate of climb and descent indicator.

• An outside air temperature gauge.

• A gyroscopic bank and pitch indicator.

• Unless another timepiece with a sweep-second hand is available, a reliable, installed timepiece with a sweep-second hand.

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