The Interstellar Collision Avoidance Regulations for Universal Starflight (ICARUS) are published by the UEE Advocacy (UEEA), and set out the "rules of the space lane" or navigation rules to be followed by starships and other vessels in space to prevent collisions between two or more vessels.
Although rules for navigating vessels in Atmosphere(Atmo) may differ, the universal rules specify that they should be as closely in line with the ICARUS rules as possible, where applicable.
Certain individuals are legally required to carry or possess a copy of the rules, such as
the owners and/or operators of certain vessels.
A commonly held misconception concerning the rules of space navigation is that by following specific rules, a vessel can gain certain “rights of way” over other vessels. No vessel ever has absolute "right of way" over other vessels. Rather, there can be a "give way (burdened) vessel and a "stand on" (privileged) vessel, or there may be two give way vessels with no stand on vessel.
A stand on vessel does not have an absolute right of way over any give way vessel, for if there is a risk of collision, a stand on vessel may still be obliged to give way so as to avoid it, if doing so will be effective and is practicable. Two vessels approaching each other on a collision course, are both deemed to be "give way" and both are required to alter course so as to avoid colliding with the other. Neither vessel has "right of way".
Part I – General
(a) These rules shall apply to all vessels in space, atmosphere of planetoid bodies, and anywhere in between.
(b) Nothing in these Rules shall interfere with the operation of special rules made by an appropriate authority for atmospheric flight.
(c) Nothing in these Rules shall interfere with the operation of any special rule made by the government of any species with respect to additional station or signal lights, shapes or comm signals for starships of war and vessels proceeding under convoy, or with respect to additional station or signal lights or shapes for mining vessels engaged in mining as a fleet.
(a) Nothing in these Rules shall exonerate any vessel, or the owner, master or crew thereof, from the consequences of any neglect to comply with these Rules.
(b) In complying with these rules due regard shall be had to all dangers of navigation and collision and to any special circumstances, which may make a departure from these rules necessary to avoid immediate danger.
Rule 2 is sometimes referred to as the "General Prudential" rule and provides for non-conformance with stated rules to prevent a collision, because what is paramount is to avoid or minimize the damaging effects of a collision, as opposed to blindly following the rules to the letter. The overall intent is to minimize actual collision taking place rather than rule compliance in and of itself, per se.
- General Definitions
For the purpose of these Rules, except where the context otherwise requires:
(a) The word “vessel” includes every description of spacecraft, including automated courier drones, atmospheric/space vehicles, and starships, used or capable of being used as a means of transportation in space.
(b) The term "vessel engaged in mining" means any vessel mining with tractor beams, lasers, drills or other mining apparatus which restrict maneuverability, but does not include a vessel mining with drones or other mining apparatus which do not restrict maneuverability.
(c) The term "vessel not under command" means a vessel which through some exceptional circumstance is unable to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel.
(d) The term "vessel restricted in her ability to maneuver" means a vessel which from the nature of her work is restricted in her ability to maneuver as required by these Rules and is therefore unable to keep out of the way of another vessel. The term "vessels restricted in their ability to maneuver" shall include but not be limited to:
(i) a vessel engaged in laying, servicing, or picking up relay beacons;
(ii) a vessel engaged in using ram scoops, surveying, or nebula operations;
(iii) a vessel engaged in replenishment or transferring persons, provisions or cargo while underway;
(iv) a vessel engaged in the launching or recovery of spacecraft, if and only if doing so limits maneuverability;
(v) a vessel engaged in mine clearance operations;
(vi) a vessel engaged in a tractor operation such as severely restricts the towing vessel and her tow in their ability to deviate from their course.
(h) The word "underway" means that a vessel is not docked.
(i) The words "length" and "breadth" of a vessel mean her length overall and greatest breadth.
(j) Vessels shall be deemed to be in sight of one another only when one can be observed visually from the other.
(k) The term "restricted visibility" means any condition in which visibility is restricted by asteroids, space dust, nebula, ion storms, star corona, or other similar causes.
Part II – Steering
Section A (for any visibility)
The rules apply in any condition of visibility (e.g., in sight or in restricted visibility).
Every vessel shall at all times maintain a proper look-out by all available means, including sight, lookout, and other sensor suites so as to make a full appraisal of the situation and of the risk of collision.
- Safe speed
Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropriate to the prevailing circumstances and conditions.
In determining a safe speed the following factors shall be among those taken into account:
(a) By all vessels:
(i) the state of visibility;
(ii) the traffic density including concentrations of mining vessels or any other vessels;
(iii) the maneuverability of the vessel with special reference to stopping distance and turning ability in the prevailing conditions;
(b) Additionally, by vessels with operational sensors:
(i) the characteristics, efficiency and limitations of the sensor equipment;
(ii) any constraints imposed by the sensor range scale in use;
(iii) the effect on sensor detection of the area of space and other sources of interference;
(iv) the possibility that small vessels, ice and other floating objects may not be detected by sensors at an adequate range;
(v) the number, location and movement of vessels detected by sensors;
(vi) the more exact assessment of the visibility that may be possible when sensors are used to determine the range of vessels or other objects in the vicinity.
- Risk of Collision
Vessels must use all available means to determine the risk of a collision, including the use of sensors (if available) to get early warning of the risk of collision by systematic observation of detected objects.
If the distance of any vessel is reducing and her bearing is not changing much or it is a large vessel or towing vessel at close distance, or if there is any doubt, then a risk of collision shall be deemed to exist.
- Action taken to avoid collision should be: positive, obvious, and made in good time.
- Narrow breach
A vessel proceeding along a narrow breach must keep to starboard.
Small vessels or sublight vessels must not impede (larger) vessels which can navigate only within a narrow breach.
- Traffic Separation Schemes
Starships must cross traffic lanes steering a course "as nearly as practicable" at right angles to the direction of traffic. This reduces confusion and enables that vessel to cross the lane as quickly as possible.
Vessels entering a traffic separation scheme should do it at an angle as small as practicable.
A traffic separation scheme does not relieve any vessel from complying with other rules.
Part II – Steering
Section B (for vessels in sight of one another)
The following rules 11–18 applies to vessels in sight of one another. (Section C has specific requirements for restricted visibility)
An overtaking vessel must keep out of the way of the vessel being overtaken. "Overtaking" means approaching another vessel at more than 22.5 degrees abaft her beam, the overtaking vessel would see only the stern light and neither of the sidelights of the vessel being overtaken.
- Head-on situations
When two vessels are meeting head-on both must alter course to starboard so that they pass on the port side of the other. If due to differences in vessel reference frames a course alteration to starboard results in both vessels altering course towards the same direction and a risk of collision still exists, both vessels will alter course by pulling up.
"Head-on" means seeing the other vessel ahead or nearly ahead so that masthead lights are actually or nearly lined up and/or seeing both her sidelights. Note that this also includes crossing situations where one vessel is crossing crossing from above or below the other.
- Crossing situations
When two vessels are crossing, that is meeting in a way that is not head-on, any vessel that sees the red port-side light of the other vessel must give way and avoid crossing ahead of the other vessel. In the event that the two vessels are inverted such that both present their port-side light to the other, both vessels are give-way and must turn to starboard.
The saying is "If to starboard red appear, 'tis your duty to keep clear".
- The give-way vessel
The give-way vessel must take early and substantial action to keep well clear.
- The stand-on vessel
The stand-on vessel shall maintain her course and speed, but she may take action to avoid collision if it becomes clear that the give-way vessel is not taking appropriate action, or when so close that collision can no longer be avoided by the actions of the give-way vessel alone.
In a crossing situation, the stand-on vessel should avoid turning to port even if the give-way vessel is not taking appropriate action. These options for the stand-on vessel do not relieve the give-way vessel of her obligations under the rules.
- Responsibilities between vessels
Except in a narrow breach, traffic separation schemes, and when overtaking (i.e., rules 9, 10, and 13)
A vessel must give way to:
a vessel not under command;
a vessel restricted in her ability to maneuver (this may include vessels towing one another;
a vessel engaged in mining;
A vessel engaged in mining when underway shall, so far as possible, keep out of the way of:
a vessel not under command;
a vessel restricted in her ability to maneuver.
Section C (for restricted visibility)
- Restricted visibility
(a) Rule 19 applies to vessels (not in sight of one another) in or near restricted visibility.
(b) All starships shall proceed at a safe speed for the condition of visibility (see Rule 6).
(c) All starships shall comply with Section I of this Part e.g., Rules 5 (lookout), 6 (safe speed), 7 (risk of collision), 8 (action to avoid collisions), 9 (narrow breaches), and 10 (TSS) with due regard for the visibility conditions.
(d) If another vessel is detected by sensors alone, and a close-quarters or collision risk is suspected, a vessel should take early and substantial action to avoid the other, but:
(i) avoid any turn to port for a vessel detected forward of the beam, except for a vessel being overtaken,
(ii) avoid any change of course toward a vessel. When the beacon signal of another vessel is received, apparently fore, a vessel should reduce speed to the minimum at which she can maintain her course, or if necessary stop, and navigate with extreme caution until there is no risk of collision.
Part III – Lights
Rules concerning lights apply in conditions of restricted visibility, and in all other circumstances when it is deemed necessary.
"Masthead light" means a white light on the centreline of the vessel showing from right ahead to 22.5 degrees abaft the beam on either side of the vessel.
"Sidelights" means a green light on the starboard side and a red light on the port side each showing from right ahead to 22.5 degrees abaft the beam on its respective side. If the vessel is less than 20 metres (66 ft) long, the sidelights may be combined in one fixture carried on the centreline of the vessel.
"Sternlight" means a white light placed as nearly as practicable at the stern showing 67.5 degrees from right aft on each side of the vessel.
“Ventral Light” means a white flashing light on the centreline of the vessel showing from right ahead to 22.5 degrees abaft the beam on either side of the vessel.
"Towing light" means a yellow light having the same characteristics as a "sternlight" defined above.
"All-round light" means a light visible from 360 degrees of all bearings.
"Flashing light" means a light flashing faster than 120 flashes per minute.
"Long tow" means that the distance between the stern of the towing vessel and the after end of the towed vessel is more that 200 meters.
- Visibility of lights
Lights must be bright enough to be visible.
- Lights displayed by vessels underway
A vessel underway must display:
a masthead light forward;
a ventral light;
A smaller craft must also display a bright all-round flashing light when taking off, landing, or flying near the surface.
- Lights for vessels towing
A vessel when towing must show two masthead lights on top of each other, instead of the masthead(s) prescribed in Rule 23;
a ventral light;
a towing light vertically above the sternlight;
if a pushing vessel and the vessel it is pushing are rigidly connected, they count together as a vessel and must show the light prescribed by Rule 23.
If the towing vessel is not normally engaged in towing operations and it is impractical to light it correctly, it is not obliged to show these lights if it is towing a vessel in distress or in need of assistance. All possible measures must be taken to show that it is towing;
- Lights for mining or salvage vessels
(a) A vessel engaged in mining, whether underway or at dock, shall exhibit only the lights and shapes prescribed in this Rule.
(b) A vessel when in mining, other than salvaging, shall exhibit:
- two all-round lights in a vertical line, the upper being red and the lower white, or a shape consisting of two cones with apexes together in a vertical line one above the other;
- when there is outlying gear extending more than 150 metres horizontally from the vessel, an all-round white light or a cone apex upwards in the direction of the gear;
(c) A vessel when not engaged in mining shall not exhibit the lights or shapes prescribed in this Rule, but only those prescribed for a vessel of her length.
- Lights for vessels not under command or restricted in their ability to maneuver
Vessels not under command or restricted in their ability to maneuver
A vessel not under command shall exhibit:
- two all-round red lights in a vertical line where they can best be seen;
- when making way through space, in addition to the lights prescribed in this paragraph, sidelights and a sternlight.
- Lights for vessels under quarantine
A vessel held under quarantine may, in addition to the lights prescribed for vessels in Rule 23, exhibit where they can best be seen three all-round red lights in a vertical line.
Part IV – Reserved pending info on Ship-to-ship comms
- Distress signals
- The following signals used or exhibited either together or separately, indicate distress and need of assistance:
(a) a gun or other explosive signal fired at intervals of about a minute;
(b) a continuous pulse with any pulse beacon apparatus;
(c) rockets or shells, throwing red stars fired one at a time at short intervals;
(d) a signal made by radiotelegraphy or by any other signaling method consisting of the group . . . — — — . . . (SOS) in the old Earth Morse Code;
(e) a signal sent by Comms consisting of the spoken word "Mayday";
(f) the Universal Code Signal of distress indicated by the UEE Military;
(g) a ship-to-planet distress alert transmitted by the ship's Comm;
(h) approved signals transmitted by Comm systems, including survival craft radar transponders.
- The use or exhibition of any of the foregoing signals except for the purpose of indicating distress and need of assistance and the use of other signals which may be confused with any of the above signals is prohibited.
Part V – Exemption
Any vessel (or class of vessel) provided that she complies with the requirements of the
Universal Regulations for the Preventing of Collisions in space, 2860, the keel of which is laid or is at a corresponding stage of construction before the entry into force of these Regulations may be exempted from compliance therewith as follows:
(a) The installation of lights with ranges prescribed in Rule 22, until 4 Standard Sol years after the date of entry into force of these regulations.
(b) The installation of lights with color specifications as prescribed in Section 7 of Annex I to these Regulations, until 4 Standard Sol years after the entry into force of these Regulations.
(c) The repositioning of lights as a result of conversion from Imperial to metric units and rounding off measurement figures, permanent exemption.
(d) (i) The repositioning of masthead lights on vessels of less than 150 meters in length, resulting from the prescriptions of Section 3 (a) of Annex I to these regulations, permanent exemption.
(ii). The repositioning of masthead lights on vessels of 150 meters or more in length, resulting from the prescriptions of Section 3 (a) of Annex I to these regulations, until 9 Standard Sol years after the date of entry into force of these Regulations.
(e) The repositioning of masthead lights resulting from the prescriptions of Section 2(b) of Annex I to these Regulations, until 9 Standard Sol years after the date of entry into force of these Regulations.
(f) The repositioning of sidelights resulting from the prescriptions of Section 2(g) and 3(b) of Annex I to these Regulations, until 9Standard Sol years after the date of entry into force of these Regulations.
(g) The repositioning of all-round lights resulting from the prescription of Section 9(b) of Annex I to these Regulations, permanent exemption.
ANNEX I – Positioning and technical details of lights
ANNEX II – Additional signals for mining vessels mining in close proximity