(Please note that the terms
Stated Performance Level (SPL) and Maximum echoing are not related
and should not be used for comparison)
The relevant sections of ISO 8729-1-2
Performance Standards for Radar Reflectors effective 22nd July
09 are shown below.
Copyright restrictions prevent us from listing the specification in full.
Applies to SOLAS ChV and X and all ships to be fitted with passive and/or Active RTE, if practicable, and covers the frequencies 3GHz (S-Band) and 9GHz (X-Band) whose wave lengths are 10 and 3cm respectively.
Performance
The reflector must have a Stated Performance Level of 7.5M2 measured in meters radar cross section (M2RCS) of at least 7.5M2 in X band and 0.5M2 in S Band mounted a minimum 4 meters above sea level.
The SPL should be maintained over 280 degrees and not below this level over any single angle of more than 10 degrees - a null and not have any distances between nulls of less than 20 degrees.
For power driven vessels and vessels designed to operate with little heel ie catamaran/trimaran, this performance should be maintained through angles of (athwartships) heel 10 degrees either side of vertical.
For sailing vessels the 7.5M2 SPL should be maintained at 20 degrees of heel either side of the vertical.
Full copies of the specification can be obtained from ISO or HMO
ISO 8729-1997 extends to
six pages and is available from HM Stationery Office, the pertinent
performance paragraphs are:
5.1.1 The maximum echoing area
of the radar reflector shall be at least 10m2
5.1.2 Its azimuthal polar diagrams
shall be such that its response over a total angle of 240 deg.
is not less that 2.5m2. The response shall not remain below this
level over any single angle of more than 10 deg.
5.1.3 These requirements shall
be assessed by reference to related azimuthal polar diagrams about
the reflectors vertical axis and tilted from the vertical at angles
not exceeding plus or minus 3 deg.
5.2 Reflecting pattern in vertical
plane The performance of the reflector up to at least plus or
minus 15 deg. from the horizontal shall be such that its response
at any inclination remains above 0.625m2 over a total angle of
at least 240deg.
(Paragraph 5.2 is commonly accepted as flawed
and was based on the performance of the 18” Octahedral.)
RORC - Royal Ocean Racing Club - ORC
- Offshore Racing Council, now part of ISAF.
These operate the Offshore Special Regulations
which prescribe the equipment etc., to be carried on Ocean Racing
Yachts. The relevant part is regulation 4.10 which reads:
4.10 Radar reflector A Radar
reflector shall be provided. If the radar reflector is octahedral
it must have a minimum diagonal measurement of 456mm (18”),
or if not octahedral must have a documented RCS (radar cross-section)
of not less that 10m2. The minimum effective height above water
is 4.0 m (13ft). Compliance with ISO 8729 is strongly recommended
as a minimum standard. In addition to (but not in place of) the
above, an RTE (Radar Target Enhancer) is recommended.
SOLAS Chapter V Regulation 19 para 2.1.7
(effective 01/07/2002)
Regulation 19 para.2.1.7 requires radar reflectors to be carried,
where practicable, by ships under 150 GT. For UK-flagged this
includes pleasure vessels.
The following notes gives further guidance
on the choice of a radar reflector for small vessels and supersede
Merchant Shipping Notice M.1638.
1.) Reflectors meeting the standards
laid down in British Standard BS 7380:1990 (ISO standard 8729:
1987) meet IMO performance standards*. Radar reflectors which
were type tested and approved to the earlier DOT Marine Radar
Reflector Specification, published in 1977, also comply with the
IMO standards.
2.) An important parameter of
a radar reflector is it's echoing area, or equivalent radar cross-section,
as this determines the amount of the radar energy which is reflected
back. Reflectors to the above standards have a maximum echoing
area of at least 10 m² with a minimum echoing area of at
least 2.5 m² over 240° of azimuth. Orientation of the
reflector must follow manufacturers recommendations if it is to
be effective.
3.) Regulation 19 takes account
of the fact that reflectors built to the above standards are relatively
large and may not be practical for fitting to smaller vessels.
The Agency considers that fitting reflectors meeting IMO standards
to vessels of 15m and above length should be practicable.
4.) Owners and operators of
craft vessels of less than 15m in length should fit reflectors
with the greatest echoing area practical. In all cases, the reflector
should be mounted as high as possible for maximum detection range,
following the manufacturer's instructions.
5.) It should be noted by Master
and Operators of all vessels that even the 10 m2 reflectors referred
to above will be difficult to detect in sea clutter on radar displays.
Masters of all vessels are reminded that this should be taken
in to account when setting lookouts and determining safe speed
as required by Rules 5 and 6 of the International Regulations
for the Prevention of Collisions at Sea.
6.) Electronic radar target
enhancers are now marketed by some manufacturers. Radar enhancers
can be considered as “other means” in the Regulation.
These have a larger equivalent radar cross-section for a physically
smaller size than radar reflectors and produce a response on a
radar display, which is stronger and more consistent, but does
not increase the apparent size of the target. Some navigation
buoys are being fitted with electronic radar enhancers and seafarers
should be aware this improves their detection range. Mariners
should note that radar enhancers currently available do not operate
in the radar “S” band.
7.) Owners and operators should
note that under Regulation 18 equipment meeting the requirements
of Regulation 19 must be type approved. However by virtue of Regulation
1.4, the Agency allows United Kingdom vessels which are too small
to fit reflectors meeting the IMO standards to fit equipment suitable
for the type and size of vessel.
Paragraph 5 above confirms our view that radar
reflectors with an RCS of 10m2 or less are of little or no use
in real sea conditions.
See
http://www.mcga.gov.uk
SOLAS Carriage Requirements
- 2.1.7 [Radar reflector]: All ships
irrespective of size shall have:...if less than 150 gross
tonnage and if practicable, a radar reflector, or other means,
to enable detection by ships navigating by radar at both
9 [X-band] and 3 GHz. [S-band]
- 2.3.2 [X-band radar]: All ships
of 300 gross tonnage and upwards and passenger ships irrespective
of size shall...be fitted with: a 9 GHz. radar, or other
means to determine and display the range and bearing of radar
transponders and of other surface craft, obstructions, buoys,
shorelines and navigational marks to assist in navigation
and in collision avoidance;
- 2.4 [AIS]: All ships of 300 gross
tonnage and upwards engaged on international voyages and
cargo ships of 500 gross tonnage and upwards not engaged
on international voyages and passenger ships irrespective
of size shall be fitted with and automatic identification
system (AIS),...
- 2.5.5 [ARPA]: All ships of 500 gross
tonnage and upwards shall,...have: an automatic tracking
aid, or other means, to plot automatically the range and
bearing of other targets to determine collision risk.
- 2.7.1
[S-band radar]: All ships of 3000 gross tonnage and upwards
shall,...have: a 3 GHz [S-band] radar or where considered
appropriate by the Administration a second 9 GHz [X-band]
radar, or other means to determine the range and bearing...which
are functionally independent of those referred to in paragraph
2.3.2; and ...
- above text extracted from www.theradarreflectorsite.org/StandardsAndRequirements.htm
The
above seems to question the misconception that only S band
is used by Ocean going vessels. Rule 7(b) of the International
Regulations for Avoiding Collisions at Sea states
(b) Proper use shall be made of radar equipment if fitted and
operational, including long-range scanning to obtain early
warning of risk of collision and radar plotting or equivalent
systematic observation of detected objects.
X band is referred to as the collision avoidance frequency
and in a Court of Law it would not help the Captains case in
collision with another vessels if it were disclosed that the
X band radar was either switched off or not being monitored.
Re RTE purchase and use
RE : EEC Countries
When purchasing an RTE for use in EU countries
it is in your own interest to check that it is “legal”.
It should, until the ETSI standard EN 302 752 becomes harmonised,
be marked as CE followed by 4 numbers followed an alert sign!
in a circle.
Following harmonisation, in certain circumstances the 4 numbers
can be omitted. But the CE and alert mark must remain.
To meet the requirements of the R&TTE directive the product
must meet ITU-R M.1176.
In the UK your Active-X-XS must be added to your Ships VHF License.
You will need to be registered to use the online service at
http://www.ofcom.org.uk/licensing/olc/
When you have logged in and see the page with your licence(s)
listed, click on amend licence and work your way through until
you come to the add equipment page. Expand the relevant section
and add your new equipment, save the changes and then print your
new licence
For other countries you must check with your
respective licensing authorities what action is required prior
to using your RTE.
Re USA
In the USA a product must carry an FCC ID and may require a
users licence. The Active-X has FCC approval ref FCC ID : XZMACTIVE-X.
FCC approval for Active-XS is pending
Re Canada
Since the Echomax Active-RTE has output power less than 1 kW
and not covered under any Canadian Radio Standards Specification
the equipment does not need to be certified for the time being.
The equipment may need a licence to operate under a radio station
licence for a ship owner according to the following conditions:
- Vessels smaller than 20m length are exempt of licence for navigation
on Canadian water. However, if they plan to navigate on international
water, a licence is required.
- Vessels larger than 20m length are require a licence.
Normally, Marina Clubs will inform the owner of ship regarding
this rule. When a licence is granted, it is for all equipment
on board of the vessel including devices where RSS do not apply.
For licence application: "IC-3020:
Application for a Maritime Mobile Radio Station Licence" is the document to consult.
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