Mayday (emergency call)

Mayday is the international distress signal in voice . It is used worldwide in the mobile maritime radio service , mobile aviation radio service and in the BOS radio service and has top priority in radio traffic .

origin

The tomb of Frederick Mockford

The term Mayday is widely attributed to Frederick Stanley Mockford (1897–1962), who is said to have been asked as chief radio officer at London-Croydon Airport with a strong connection to Le Bourget Airport near Paris to find a word that on the one hand indicated an emergency, on the other but would also be understood with equal certainty by everyone, pilots and ground personnel alike. Like a number of other characters in international communications, such as Pan-pan and Sécurité is also Mayday to the French returned: The letters, which in English as that interpretation May Day suggests', is here as phonetic reproduction of a cry for help [ mede ], and this either as a jussive infinitive M'aider , possibly shortened from Venez m'aider! 'Come help me!' or as imperative M'aidez! ,Help me!' understood.

seafaring

The radio emergency signal MAYDAY indicates a distress at sea and initiates the distress message . Emergency at sea means that a watercraft is in distress or a person in danger of death and needs immediate help.

Examples of emergencies at sea

Water ingress with acute threat of sinking; Pirate attack; Collision with impending sinking; Stranding with threatening sinking; List with threatening decline; Fire on board; Man overboard ; Impossible to maneuver with impending dangerous stranding or collision, ricocheting and capsizing due to breakers. The responsible skipper decides whether there is an emergency at sea based on his or her subjective point of view. Objectively speaking, the existence of an emergency may depend on the experience of the crew and the equipment of the ship.

Alerting

In marine radio , distress traffic takes place via the following media:

VHF DSC channel 70 (156.525 MHz) (digital selective calling only)
VHF channel 16 (156.80 MHz) (spoken message)
GW / KW DSC
2182 kHz ( limit wave )
4125, 6215, 8291, 12290, 16420 kHz ( HF ), optionally on the working channel of a coast station

Emergency calls near the coast or via satellite telephone can also be made via

Telephone + 49-421-53687-0 (Sea rescue control center of the DGzRS in Bremen)
Abbreviated dialing 124124 from German cellular networks

DSC radio

Today the emergency call is usually made via a DSC device and in accordance with the rules of the Implementation Regulations for the radio service (VO radio). In addition to the ships requiring equipment ( SOLAS ), all modern charter ships now have a VHF device with a DSC controller.

The emergency call button is usually labeled in red with "Distress" and protected against false activation under a cover flap. As a further safeguard, it must be pressed continuously for several seconds on some devices.

The radio system sends a digital sea alert with the following content:

MMSI of the ship
Position of the ship (via NMEA - GPS receiver or by hand)
Type of emergency (English: Man over board, Pirates attack, Ship sinking, Fire etc.)

Emergency message

The DSC emergency alarm is then followed by the emergency call, followed by the actual emergency message via voice radio:

template	example
Emergency call Mayday Mayday Mayday This is …………………… (Ship name - 3 times -, callsign and MMSI)	Mayday Mayday Mayday This is Yacht Holiday Holiday Holiday HBY2384 269787381
Emergency message Mayday ........................ (Ship name, call sign and MMSI)	Mayday Yacht Holiday Holiday Holiday HBY2384 269787381
position _ _ Degrees _ _ Decimal _ Minutes North / South _ _ _ Degrees _ _ Decimal _ Minutes East / West	position 49 Degrees 54 Decimal 3 Minutes North 005 Degrees 13 Decimal 7 Minutes West (or) 5 nautical miles south of Lizard Point
at _ _ _ _ UTC	at 0815 UTC
(Type of emergency) (Type of help required) (More information)	Yacht is sinking Require urgent assistance 4 persons on board. White hull with red stripes and dark sails.
Over	Over

All numbers - as well as letters in callsigns - are spelled individually. To avoid confusion, degrees of latitude are always given with two digits and degrees of longitude with three digits. The above example length specification is spoken as "Zero-Zero-Five Degrees, One-Three Decimal Seven Minutes West" .

Radiotelephony without DSC

In non- GMDSS radio traffic, the emergency call and the emergency report are made in the same way, only that the MMSI is omitted because it was not previously sent via DSC. This also applies to urgency and safety messages.

Receiving an emergency call

The receipt of an emergency call is usually confirmed via GMDSS by coastal radio stations and / or MRCC maritime emergency control centers with the digitally transmitted message <DISTRESS ACKNOWLEDGE> . This then takes over the coordination of all further actions.

In non-DSC radio, receipt of an emergency call is confirmed with RECEIVED MAYDAY . The confirmation is usually also made by a maritime emergency control center. A confirmation by another radio station should only be given if

the marine radio station is requested to do so by the land radio station (because the land radio station does not reach the distressed party directly)
No confirmation from a land radio station has been received for five minutes
no other communication with the ship in distress is detected.

On shortwave, ships never send an acknowledgment of receipt via DSC, but only via radio telephony if necessary.

template	example
acknowledgment of receipt Mayday (Name of the ship in distress) (or callsign) (or MMSI)	Mayday Yacht Holiday or HBY2384 or 269787381
This is (Own ship name, callsign and MMSI)	This is Yacht Helpful HBY3412 269976123
Received Mayday	Received Mayday

The signal word Mayday is used before any emission related to emergency traffic.

Radio silence

An emergency call has priority over any other radio communication. An accident victim or the head of emergency traffic can request silence with the call SILENCE MAYDAY during an ongoing emergency traffic . Like many key words in radio, the origin of SILENCE is French and should be pronounced accordingly. (The French "Silence!" Means "Quiet!") The radio silence can be canceled with SILENCE FINI .

Transfer an emergency call

As MAYDAY RELAY disclosure refers to an emergency call in the name of another ship. This is often used by coastal radio stations when they want to request nearby ships to come to the aid of the disturbed vessel. The coastal radio station often has a better communication infrastructure than a (small) ship and, by relaying it, reaches a larger number of potential helpers than the distressed ship directly. Conversely, forwarding to the coast radio station may be necessary because the damaged party is outside the direct range of the coast radio station or because the emergency was determined in a way other than radio (e.g. observation of signal rockets, smoke pots, fog horns, etc.).

If possible, the distress call should be forwarded directly to a coast station via DSC. However, this function is not supported by all radios. If possible, transmission via radio telephony should also be directed to the coastal radio station.

template	example
Call to forward a distress message Mayday Relay Mayday Relay Mayday Relay (Name of the called station) This is …………………… (Without MMSI, as no DSC alarm was triggered)	Mayday Relay Mayday Relay Mayday Relay Bremen Rescue Bremen Rescue Bremen Rescue This is Yacht Helpful Helpful Helpful HBY3412
Over	Over
Coast station response Mayday (Name of own station) This is ……………………	Mayday Yacht Helpful This is Bremen Rescue
go ahead	go ahead
Forwarding the emergency call (Name of coast station) This is …………………… (Ship name - once - and call sign)	Bremen Rescue This is Yacht Helpful HBY3412
Content of the emergency message We received the following distress message on Channel ……	We received the following distress message on Channel 16
(Content of the report)	Mayday Yacht Holiday Holiday Holiday HBY2384 269787381 position 49 Degrees 54 Decimal 3 Minutes North 005 Degrees 13 Decimal 7 Minutes West at 0815 UTC Yacht is sinking Require urgent assistance 4 persons on board. White hull with red stripes and dark sails.
or: own observation Position ……… We observed…	position 49 Degrees 43 Decimal 50 Minutes North 005 Degrees 13 Decimal 3 Minutes West We observed red flares about 10 nautical miles north of our current position.
Over	Over

If the message to be forwarded was recorded by radio, it is forwarded verbatim as far as possible. If the responsible coast station cannot be reached, the call is sent to All Stations .

Cancel an emergency call

If no further remedial measures are necessary, for example because the person who was overboard could be resumed or because an alarm was accidentally triggered, the person who triggered the alarm can give the all-clear:

template	example
Cancel an alarm 3x all stations	All Stations All Stations All Stations
This is (3 × own ship name, call sign and MMSI)	This is Yacht Holiday HBY2384 269787381
Please cancel my distress alert of _ _ _ _ UTC	Please cancel my distress alert of 0815 UTC
Over	Over

The radio traffic should then be monitored for a certain period of time in order to be able to respond to any queries.

Legal consequences

An emergency call may only be made by order of the skipper. Every ship in the area is obliged to provide help. Successful help can result in a fee in individual cases. The very simple triggering of an emergency alarm via the DSC controller often leads to costly false alarms. Distress reports - own and received - and the measures taken must always be recorded in the logbook.

Legal basis

The handling of emergency traffic is regulated internationally by the Radio Regulations (VO Funk). The regulations contained therein are implemented at national level in corresponding laws or ordinances.

North and east Sea

In the German area of the North and Baltic Seas , the national task of sea rescue has been transferred to the DGzRS and is coordinated for the North and Baltic Seas via the RCC or MRCC Bremen Rescue Radio . The rescue from the air is also carried out under the leadership of the DGzRS via the command center of the Navy in Glücksburg .

aviation

Useful in the aeronautical radio transmitted on the frequency currently in use or an emergency frequency. For example, the international emergency frequency (121.5 MHz ; VHF ) is monitored at all controlled airports.

The emergency call should include the following:

Initiation with the (preferably triple) emergency signal MAYDAY
called ground station
own radio call identification (mandatory), e.g. B. "D-EFSR" or "Disaster Airlines 123"

The emergency message that follows should contain the following information:

Type of emergency, e.g. B. "Engine Failure"; “ VFR pilot in IMC ”; "lost"; "Pressure loss in the cabin"
Intentions of the pilot, e.g. B. Emergency landing
Type of help you want, e.g. B. "Request radar vectors"; "Request QDM "; "Keep the airspace to the south free"
Information about position, course and altitude

In practice, however, it should be noted that the pilot may design the emergency call individually and transmit it as he deems appropriate for a quick problem solution.

An emergency call should not be made too late, even if it originated from a mistake or error on the part of the pilot. It can also be withdrawn again.

Air traffic control will initiate SAR actions if necessary .

If no discrete transponder code is switched to the emergency call should additionally transponder to the emergency call code 7700 are switched. The pilot can also be reminded of this by the ground radio station (" Squawk 7700"). This marks the aircraft on the air traffic control radar screen with an additional symbol (e.g. a star).

If the radio has failed (or if this is suspected), an emergency call can also be made by simply switching the transponder code 7700 .

The radio station in distress and the radio station controlling the emergency traffic can impose radio silence on all or certain other radio stations with the instruction KEEP RADIO STILLE MAYDAY / STOP TRANSMITTING MAYDAY . After the air emergency has ended, air traffic control will release the frequency again for general radiotelephony.

BOS radio, breathing apparatus

When deployed with respiratory protection , emergency services from the fire brigade , THW and other BOS organizations draw attention to an emergency by giving a Mayday call. This can be, for example, the failure of the respiratory protection technology, a medical emergency or the loss of orientation.

The troop in distress reports in accordance with the fire brigade regulation FwDV 7 according to the following scheme via DMO digital or 2m analog BOS radio :

“MAYDAY, MAYDAY, MAYDAY

Here <radio call name *> (* in practice mostly the 'troop name' (e.g. attack troop 21/1))

MAYDAY come. "

As soon as a squad makes the MAYDAY call, all remaining radio traffic on the relevant call group / channel must be stopped in order to enable the emergency call to be sent completely and queries from the manager without being disturbed. With the information given, the security team hurrying to help knows where the troop in distress is and what happened to it.

For exercises it is recommended not to use the word MAYDAY in order not to delay / overlook any real emergencies that may arise. Instead, the word MAYDAY should be replaced by the term “for exercise”, similar to how it is used in the Bundeswehr , especially the Navy.

The now widespread digital BOS radios have an emergency call button, which switches the radio to the so-called "emergency call mode". The radio in question now has speaking priority over all other intercom stations and, depending on the configuration, is switched to permanent transmission for a certain period of time (approx. 30 seconds) in order to enable the squad to make the emergency call without pressing the transmission button permanently. As long as the emergency call mode is not reset manually, all radio messages from the device concerned still have priority over all other intercom units.

In the so-called TMO operation (Trunked Mode Operation), which is used for communication with distant call stations (e.g. control center), the digital radio sends further information when the emergency button is pressed, such as B. GPS position of the radio to the control center . The purpose of this is to enable assistance to be provided more quickly.

Individual evidence

↑ It's MayDay - But That Means Trouble for Aviators. In: Yorkshire Air Museum. May 1, 2017, accessed March 24, 2019 .

^ John Hart: The National CV of Britain . Tadley 2012.

↑ Michèle Fruyt, Les deux types de motivation dans certaines langues indo-européennes (français, latin, ...) in: Paul Valentin / Michèle Fruyt (ed.), Lexique et Cognition , Paris 1998, ISBN 2-84050-109-0 , P. 55

↑ Broder Carstensen / Ulrich Busse / Regina Schmude, Anglizismensprachebuch. The influence of English on German vocabulary after 1945 , Vol. 1 (A – E), Berlin 2001, ISBN 3-11-017169-4 , p. 891

^ "May Day" Is Airplane SOS , in: The Wireless Age , June 1923 , p. 52.

↑ The handbook Martin Haspelmath et al. (Ed.): Language Typology and Language Universals - Sprachtypologie und Sprachliche Universalien - La typologie des langues et les universaux linguistiques . Volume 2/2. Berlin / New York 2001, ISBN 3-11-017154-6 , p. 1602 denotes m'aidez! as Pseudo French 'Pseudo-French', probably because of the pronominal object placed in front of the imperative, which was possible in older French, cf. Jean Girodet: Pièges et difficultés de la langue française . Paris 2007, p. 1036 ; Georg Radisch: The pronouns in Rabelais. A contribution to the French grammar of the XVI. century . Leipzig 1878, p. 23.

↑ NfL I 278/07 . Announcement on radiotelephone procedures. In: German Air Traffic Control (ed.): Notices to Airmen Part I . Langen November 22, 2007, p. 9 ( aeroclub-nrw.de [ Memento of July 28, 2011 in the Internet Archive ] [PDF; accessed on April 7, 2011]). NfL I 278/07 ( Memento from July 28, 2011 in the Internet Archive )

[1] It's MayDay - But That Means Trouble for Aviators. In: Yorkshire Air Museum. May 1, 2017, accessed March 24, 2019 .

[NationalCVBritain-2] John Hart: The National CV of Britain . Tadley 2012.

[3] Michèle Fruyt, Les deux types de motivation dans certaines langues indo-européennes (français, latin, ...) in: Paul Valentin / Michèle Fruyt (ed.), Lexique et Cognition , Paris 1998, ISBN 2-84050-109-0 , P. 55

[4] Broder Carstensen / Ulrich Busse / Regina Schmude, Anglizismensprachebuch. The influence of English on German vocabulary after 1945 , Vol. 1 (A – E), Berlin 2001, ISBN 3-11-017169-4 , p. 891

[5] "May Day" Is Airplane SOS , in: The Wireless Age , June 1923 , p. 52.

[6] The handbook Martin Haspelmath et al. (Ed.): Language Typology and Language Universals - Sprachtypologie und Sprachliche Universalien - La typologie des langues et les universaux linguistiques . Volume 2/2. Berlin / New York 2001, ISBN 3-11-017154-6 , p. 1602 denotes m'aidez! as Pseudo French 'Pseudo-French', probably because of the pronominal object placed in front of the imperative, which was possible in older French, cf. Jean Girodet: Pièges et difficultés de la langue française . Paris 2007, p. 1036 ; Georg Radisch: The pronouns in Rabelais. A contribution to the French grammar of the XVI. century . Leipzig 1878, p. 23.