Electronic conspicuity is the ability of an aircraft to be seen, and to see others, using electronic systems rather than the naked eye alone. If you fly general aviation, this concept affects you directly. A growing share of the aircraft around you are electronically visible. Some are not. That gap is the problem electronic conspicuity exists to solve.
The term appears increasingly in EASA guidance documents, FAA advisory circulars, and CAA policy papers. But strip away the regulatory language and the idea is simple: make every aircraft in the sky visible to every other aircraft, regardless of what avionics each one carries.
The Visibility Gap in General Aviation
Commercial airliners carry Mode S transponders, TCAS, and certified ADS-B Out. They broadcast their position continuously, and they receive traffic data continuously. The system works because participation is universal above a certain tier of aviation.
General aviation is different. A Cessna 172 flying out of a controlled airport may have a Mode S transponder and ADS-B Out. A Piper J-3 Cub at a grass strip may have nothing. A Schleicher ASK 21 glider thermalling at 3,000 ft might carry FLARM but no transponder. A DJI Matrice 300 drone surveying a pipeline corridor might be visible only through a U-space network.
All of these aircraft share the same air. Not all of them can see each other. That is the GA visibility gap, and it is not a theoretical concern. Airprox reports from the UK Airprox Board and NASA's Aviation Safety Reporting System consistently show that many close encounters in uncontrolled airspace involve at least one aircraft with limited or no electronic visibility.
Why "See and Avoid" Is Not Enough
Every pilot learns the see-and-avoid principle during primary training. Scan outside. Keep your head on a swivel. It is foundational, and it is genuinely important. But it has hard limits.
The human eye has blind spots. High-wing aircraft obscure traffic above. Low-wing aircraft hide traffic below. In a turn, the inside wing blocks exactly the quadrant you need to see. A converging aircraft on a constant bearing shows almost no relative motion, making it extraordinarily difficult to detect visually until it is close.
Weather degrades visual scanning. Haze at 5 NM visibility is legal for VFR in many jurisdictions. It also means you might not see a closing aircraft until it is inside 1 NM. In-flight visibility that satisfies the minimum legal requirement and visibility that provides adequate time to react are two different things.
Cockpit workload competes with scanning. A student pilot on a solo cross-country, managing navigation, radio calls, and fuel planning, cannot maintain a continuous visual scan. Neither can an experienced pilot hand-flying an approach into an unfamiliar airfield while briefing the arrival procedure. Workload rises, scan quality drops. This is well documented in human factors research and familiar to anyone who has flown a busy traffic pattern.
Electronic conspicuity does not replace visual scanning. It supplements it. A traffic alert on a display gives you a direction to look, which is far more effective than sweeping the entire sky hoping to spot a speck.
EC Technologies: More Than Just ADS-B
Electronic conspicuity is an umbrella term. Several technologies contribute to the overall picture, each with different strengths.
ADS-B (Automatic Dependent Surveillance - Broadcast)
The most widely discussed EC technology. ADS-B Out broadcasts an aircraft's GPS-derived position, altitude, velocity, and identification on 1090 MHz (used globally) or 978 MHz UAT (used in the US below 18,000 ft). ADS-B In receives those broadcasts and displays traffic to the pilot. The FAA mandated ADS-B Out in most controlled US airspace from 2020. EASA is pursuing a lighter-touch approach through its ADS-L (ADS - Light) initiative, designed to bring EC to GA without imposing the full cost of certified transponder installations. For a deeper look at how ADS-B In and Out work together, see ADS-B In vs ADS-B Out: What Every GA Pilot Needs to Know.
FLARM
Originally developed for gliders in Switzerland, FLARM calculates short-term collision risk by exchanging position and predicted flight path data between equipped aircraft. It is standard equipment in the European gliding community and increasingly common on light aircraft, helicopters, and some commercial operations near mountainous terrain. At a busy Alpine gliding site, FLARM can be the difference between orderly thermalling and a near miss at 6,000 ft. It operates on its own frequency band and protocol, separate from ADS-B, which means an ADS-B-only receiver will not see FLARM-equipped traffic unless the data is bridged through a network like SafeSky.
Mode S Transponders
These have been the backbone of air traffic surveillance for decades. They reply to radar interrogation with aircraft identification and pressure altitude. While not GPS-based, Mode S transponders make aircraft visible to ATC radar systems and to TCAS-equipped aircraft. Many GA aircraft carry Mode S even if they lack ADS-B Out.
OGN and Community Networks
The Open Glider Network (OGN) collects position data from FLARM and other devices via a network of volunteer-operated ground stations. Platforms like SafeSky aggregate data from 30+ sources, including ADS-B, FLARM, OGN, pilot apps, and drone registries, to build a composite traffic picture that no single technology can match alone. These community-driven networks are a practical bridge for the mixed-equipage reality of GA airspace.
TIS-B and FIS-B
In the US, FAA ground stations rebroadcast radar-derived traffic data (TIS-B) and flight information (FIS-B) to ADS-B In receivers. TIS-B fills gaps where non-ADS-B aircraft are tracked by radar but would otherwise be invisible to ADS-B-only equipped cockpits.
How EC Fits Alongside Traditional Traffic Services
Electronic conspicuity does not replace ATC, radar surveillance, or TCAS. Each layer addresses a different part of the problem.
ATC radar provides surveillance in controlled airspace and around equipped airports. TCAS provides last-resort resolution advisories on transport-category aircraft. Neither extends reliably into the low-level, uncontrolled airspace where most GA flying happens.
EC fills that gap. A portable ADS-B receiver picking up traffic at 2,500 ft over a rural training area provides awareness that no radar service or TCAS installation can offer in that environment. This is precisely the kind of situational awareness gap that catches pilots off guard.
Think of it as layered defence. Radar covers the upper structure. TCAS protects equipped aircraft from mid-air collision. EC extends electronic visibility down to the grass strip, the glider ridge, the paramotor launch site. Each layer catches what the others miss.
Why This Matters Now
Three trends are converging to make electronic conspicuity more urgent than it was even five years ago.
GA traffic is growing. Post-pandemic recovery has pushed flight training activity and recreational flying above pre-2020 levels in many regions. Eurocontrol forecasts continued growth across European airspace through the end of the decade. In the US, the FAA reports record student pilot certificate issuances in recent years. More aircraft in the sky means more potential conflicts, particularly around popular training areas and uncontrolled aerodromes where traffic services are limited or nonexistent.
Drones are entering shared airspace. U-space (Europe) and UAS integration (US) programmes are creating corridors where unmanned and manned aircraft will operate in proximity. Drones will participate through remote ID and network-based tracking. Manned GA aircraft need their own electronic presence in that ecosystem to be seen and to see drone traffic.
Mixed equipage is the reality for the foreseeable future. Not every aircraft will carry ADS-B Out. Gliders, vintage aircraft, ultralights, and microlights often lack the electrical system or the budget for certified transponder installations. EC solutions that work across multiple protocols and data sources, rather than depending on a single technology, are the realistic path forward. EASA's ADS-L initiative explicitly acknowledges this by promoting interoperability between ADS-B, FLARM, and network-based solutions.
What This Means for You
If you fly GA, electronic conspicuity is already shaping the airspace around you. Some of the traffic near your home airfield is broadcasting ADS-B. Some is sharing position through SafeSky or FLARM. Some is invisible.
The practical question is whether you can see that traffic, and whether that traffic can see you. Every flight where you lack that awareness is a flight where you are relying entirely on your eyes and on the hope that converging traffic sees you first.
A portable ADS-B receiver is the lowest-barrier way to participate. No installation, no aircraft downtime, no panel modification. Devices like SkyRecon go further by combining dual-band ADS-B reception (1090 + 978 MHz) with SafeSky Inside integration, pulling from 30+ traffic sources to give you the most complete picture available in a portable device. The built-in 3.4" display means you get that awareness even without a tablet connected.
This post is part of our Complete Guide to Electronic Conspicuity and Portable ADS-B in General Aviation. The guide covers everything from choosing the right device to understanding the regulatory landscape across FAA and EASA jurisdictions. If electronic conspicuity is new to you, that is the best place to go next.