Night Join at an Unlit, Non-Towered Aerodrome
You are flying a Cessna 172 on a night VFR cross-country and intend to join a straight-in approach to runway 27 at a non-towered aerodrome. There is no ATC service. The pilot-activated lighting on 123.05 is off. On the radio you hear a Beechcraft Baron call 'downwind for runway 27' and a helicopter call 'lifting from the apron for a local detail'. You activate the runway lights at 5 NM. At 3 NM you see a steady white light slightly left of your nose, apparently closing, with no red or green visible; a few seconds later a second set of lights showing red and green appears to your right. Cloud base is 2,500 ft, visibility 10 km, wind 240/12. Your approach speed is 70 kt; the Baron reports 150 kt indicated on a 2 NM base and says he will 'keep it tight'. Your crosswind and tailwind limits are not a factor.
1. At 3 NM, who has right of way, and what is your plan for the next three minutes?
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Apply the rules, then apply judgement. Under Annex 2, an aircraft in flight gives way to aircraft landing or in the final stages of an approach; an aircraft on the ground gives way to aircraft in flight; when two aircraft converge at the same level the one with the other on its right gives way; head-on, both alter course to the right; the overtaking aircraft keeps clear. You are on a 3 NM straight-in final. The Baron is on base - still in flight, not yet on final - so while he remains on base you have right of way. The helicopter, on the ground, must give way to both of you.
Where the rules stop. The Baron is twice your speed and has said he will 'keep it tight'. Once he rolls out on final both of you are 'aircraft on final' and the right-of-way rules no longer sequence you. At 150 kt against 70 kt he will close quickly, and he may not have you in sight against the unlit background.
Plan. Make a specific call - your position, your speed, your intention, e.g. '3 mile final, 70 knots, will take the first exit; Baron, are you ahead of me?' Slow to approach speed early. Set a firm go-around gate (not below 500 ft AGL unless the runway is assured clear and the Baron is well ahead). Do not rely on the right of way: Annex 2 expressly does not relieve you of the duty to avert a collision.
2. What can you legitimately conclude from the single steady white light, and from the red-and-green pair?
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From the steady white light: very little. A white-only display is consistent with the tail/stern light of an aircraft moving away and opening the range, an aircraft at long range whose coloured wingtip lights are not yet resolved, a ground vehicle or obstacle, or an aircraft with failed or unpowered position lights. A single white light at night gives no reliable distance, closure rate or altitude. Its apparent movement is your only clue and it is easily misread; do not assume it is a non-conflicting aircraft just because you cannot classify it.
From the red-and-green pair: both wingtip colours presented simultaneously means you are looking roughly at the aircraft's nose or tail-on aspect - a converging or head-on geometry, not a lateral pass. Red is the port side, green the starboard side, so the balance between them tells you roughly which side is presented, and a change in that balance tells you relative motion. What it does not tell you is altitude, range or whether the other pilot has seen you.
Practical consequence. Treat both sightings as conflicts until resolved by sight and radio. Turn on landing and strobe lights so you are conspicuous, make a position call identifying yourself relative to the aerodrome, and be prepared to break off. At night the classic failure mode is two aircraft each assuming the other is the one with the right of way.
3. The Baron stops answering your calls. State your actions and your go-around criteria.
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Assume he is there and has not heard you. Radio silence changes nothing about the traffic; it only removes your ability to sequence. Continue to transmit blind - position and intentions - because a third aircraft may be listening even if he is not, and because if his radio is merely selected to the wrong frequency the calls still matter to everyone else.
Actions. Slow early to give yourself time; keep the aircraft trimmed and configured; ensure the runway lights are on and remain on; check the helicopter is not lifting into your path; fly a stable approach with a defined decision point. Sight the Baron using strobes and landing light, not just the position lights.
Go-around criteria - decide them now, not at 300 ft: runway or approach not clearly clear of the Baron; any doubt about his position relative to the runway; unstable approach by 500 ft AGL (speed, sink rate, centreline); no visual contact with the lights at the minima you set for yourself; any aircraft, vehicle or animal on the strip.
After the go-around. Fly a published or standard circuit direction, re-announce, and if the situation persists land at another aerodrome. On the ground, file a report if an airprox occurred - the SMS can only fix what it sees.