Understanding conjunction screening requirements, maneuver coordination, and the FCC’s expectations for active debris avoidance

Introduction

What are FCC collision avoidance requirements? Under the FCC’s enhanced orbital debris mitigation framework, satellite operators are expected to actively monitor conjunction risks, coordinate with other operators when close approaches are identified, and report collision avoidance maneuvers as part of ongoing compliance obligations. These requirements — formalized in the 2022 debris mitigation rulemaking and reinforced through 2024 and 2025 enforcement actions — create operational duties that extend throughout the satellite’s mission life.

For CubeSat and SmallSat operators, collision avoidance obligations are often underestimated during mission planning. Many teams focus on launch and early operations, assuming that conjunction events are rare or that external services (like Space Force’s 18th Space Defense Squadron) will handle avoidance automatically. In reality, operators bear responsibility for conjunction screening decisions, maneuver execution, and coordination — and the FCC holds operators accountable when these responsibilities are not fulfilled.

This post explains what collision avoidance obligations the FCC expects, how conjunction screening works in practice, and what must be tracked and reported to demonstrate compliance.

The Regulatory Foundation: FCC Debris Mitigation Rules and Conjunction Assessment

The FCC’s collision avoidance requirements are grounded in Part 100’s orbital debris mitigation framework, which requires operators to:

• Minimize the probability of collision with other satellites and debris.
• Implement procedures for screening conjunction warnings and coordinating maneuvers with affected parties.
• Maintain operational capability to maneuver when conjunction risks exceed acceptable thresholds.
• Report collision avoidance activities to the FCC as part of ongoing operational compliance.

These obligations are not discretionary. The FCC views active collision avoidance as a core operational duty, comparable to maintaining authorized frequency use or orbital parameters. Operators who fail to screen conjunctions, who ignore warnings, or who maneuver without coordination face enforcement exposure.

The Enhanced Operational Compliance: New Data Reporting, Ephemeris Sharing, and Safety Requirements Under 2026 FCC Rules post discusses the broader operational reporting framework that collision avoidance fits within.

What Conjunction Screening Actually Involves

Do CubeSat operators need conjunction screening? Yes. Conjunction screening is the process of analyzing whether your satellite’s projected orbit will bring it within a dangerous proximity to another object — satellite, debris, or rocket body — and assessing whether a collision avoidance maneuver is required.

Most operators rely on external services for conjunction data:

Space Force 18th Space Defense Squadron (18 SDS) Conjunction Data Messages (CDMs)

The primary source of conjunction warnings for most U.S. and allied satellite operators is the 18 SDS, which provides free screening services through Space-Track.org. Operators submit orbital data (ephemeris), and 18 SDS returns CDMs identifying predicted close approaches. CDMs include miss distance, probability of collision, and time of closest approach.

Important limitation: 18 SDS screening is a service, not a regulatory obligation imposed on the Space Force. The government provides warnings but does not make avoidance decisions — that responsibility remains with the operator.

Commercial conjunction screening services

Commercial providers (LeoLabs, COMSPOC, AGI, Slingshot Aerospace) offer enhanced conjunction screening with higher fidelity tracking, more frequent updates, and analysis tools that help operators assess risk and plan maneuvers. These services are subscription-based and often provide earlier warnings and better accuracy than government data alone.

Internal screening using publicly available two-line element (TLE) data

Some operators perform independent conjunction analysis using publicly available TLE data from Space-Track.org. This approach is lower cost but also lower fidelity — TLE data has inherent uncertainty and may not capture all conjunction risks, particularly for small debris.

The FCC does not mandate a specific screening service, but it expects operators to have a functional conjunction screening process in place and to act on warnings received. Ignoring CDMs or failing to screen entirely is non-compliance.

FCC Expectations for Maneuver Decision-Making

When a conjunction warning is received, operators must evaluate the risk and decide whether to maneuver. The FCC does not prescribe specific probability-of-collision thresholds that trigger mandatory maneuvers — instead, it expects operators to apply industry best practices and to document their decision-making process.

Commonly used thresholds include:

• 1 in 10,000 (Pc > 1e-4) — considered the threshold above which maneuvers are typically executed for most operational satellites.
• 1 in 100,000 (Pc > 1e-5) — threshold at which operators begin active monitoring and coordination, even if immediate maneuver is not required.
• Risk assessment beyond raw probability — considering miss distance, relative velocity, object size, and uncertainty in tracking data.

Operators should establish internal collision avoidance policies that define their thresholds and decision criteria. These policies should be documented and applied consistently. During FCC audits or enforcement inquiries, operators who can demonstrate systematic, documented decision-making fare better than those who make ad hoc judgments.

The What FCC Compliance Audits Actually Look For: A Preparation Guide for CubeSat Operators post discusses how compliance documentation supports regulatory reviews.

Coordination Requirements: When You Must Contact Other Operators

If a conjunction warning involves another active satellite (as opposed to debris or an inactive object), coordination with the other operator is expected before maneuvering. This coordination serves several purposes:

• Confirming that both operators are aware of the conjunction and agree on which satellite will maneuver (or whether both will maneuver cooperatively).
• Ensuring that maneuvers do not create secondary conjunction risks with other objects.
• Sharing updated ephemeris data after maneuvers so both operators can update their tracking.

Coordination typically occurs through Space Data Association (SDA) or direct operator-to-operator contact. The SDA operates a conjunction data sharing platform that facilitates coordination between member operators.

FCC enforcement precedent indicates that operators who maneuver without attempting coordination — particularly if the maneuver creates a conjunction risk for the other party — face regulatory consequences. Coordination is not optional when both objects are active, maneuverable satellites.

What Must Be Reported to the FCC

How do I report collision avoidance maneuvers to the FCC? The FCC expects operators to maintain records of all conjunction events and maneuvers, and to report significant events as part of ongoing compliance obligations. Specific reporting requirements include:

Routine reporting: Annual or biennial summaries

Operators should include collision avoidance statistics in periodic compliance reports — number of CDMs received, number of high-risk conjunctions (above operator-defined thresholds), number of maneuvers executed, and coordination activities. This demonstrates active debris mitigation compliance.

Event-driven reporting: Notification of significant maneuvers or near-misses

The FCC expects notification when collision avoidance maneuvers are executed in response to extremely high-risk conjunctions (e.g., Pc > 1e-3), when maneuvers significantly alter orbital parameters outside normal operations, or when coordination failures occur that create secondary risks.

Post-conjunction reporting: Outcomes and lessons learned

If a conjunction occurs (meaning the objects actually passed within close proximity, even if no collision happened), operators should document the event and assess whether screening processes, thresholds, or coordination procedures should be updated. The FCC may request this documentation during audits or enforcement reviews.

Collision Avoidance for CubeSats: Special Considerations

CubeSats face unique collision avoidance challenges:

Limited or no maneuverability

Many CubeSats — particularly 1U and 2U platforms — have no propulsion systems and cannot execute collision avoidance maneuvers. This does not exempt them from conjunction screening obligations. Non-maneuverable satellites must still monitor conjunctions, coordinate with other operators (informing them that the CubeSat cannot maneuver), and rely on maneuverable satellites to avoid collisions.

The FCC has indicated that non-maneuverable satellites face higher scrutiny during authorization reviews, particularly for missions in congested orbital regimes. Operators should demonstrate that their orbital selections minimize conjunction risk and that they have processes for tracking and reporting events even when they cannot maneuver.

Tracking uncertainty and small radar cross-section

CubeSats are difficult to track accurately, leading to higher uncertainty in conjunction predictions. Operators should account for this uncertainty when setting maneuver thresholds — conservative thresholds (e.g., maneuvering at Pc > 1e-5 instead of 1e-4) may be appropriate for CubeSats with poor tracking fidelity.

Constellation coordination complexity

CubeSat constellations with dozens or hundreds of satellites face conjunction screening at scale. Each satellite requires individual screening, and maneuvers on one satellite can create conjunction risks for others in the constellation. Operators should implement automated screening and coordination workflows rather than manual per-satellite analysis.

Building a Compliant Collision Avoidance Workflow

1. Register with Space-Track.org and configure CDM delivery for your satellite(s). Ensure CDMs are received by operations personnel who can act on them within the warning timeframe (typically 24–72 hours before closest approach).
2. Establish internal collision avoidance policies defining probability-of-collision thresholds, maneuver decision criteria, and coordination procedures. Document these policies and train operations staff.
3. Maintain a conjunction event log recording all CDMs received, risk assessments performed, maneuver decisions made, and coordination activities. This log is essential for demonstrating compliance during audits.
4. Join the Space Data Association or establish direct coordination channels with operators of nearby satellites. Do not assume coordination will happen automatically through government channels.
5. Include collision avoidance statistics in FCC compliance reports and notify the FCC of significant maneuvers or near-miss events.
6. Conduct periodic reviews of conjunction screening performance — are thresholds appropriate? Are coordination processes effective? Are there patterns of high-risk conjunctions that suggest orbital parameter adjustments?

Frequently Asked Questions (FAQ)

Q: What are FCC collision avoidance requirements?

A: FCC requirements include: implementing conjunction screening processes to monitor collision risks, coordinating with other operators when close approaches are identified, maintaining capability to maneuver when risks exceed acceptable thresholds, and reporting collision avoidance activities as part of ongoing compliance obligations.

Q: Do CubeSat operators need conjunction screening?

A: Yes. All satellite operators, including CubeSat missions, must implement conjunction screening processes. This typically involves registering with Space Force 18 SDS for free CDM services or subscribing to commercial screening providers. Even non-maneuverable CubeSats must monitor conjunctions and coordinate with other operators.

Q: How do I report collision avoidance maneuvers to the FCC?

A: Report collision avoidance activities through: routine periodic compliance reports including CDM statistics and maneuver counts, event-driven notifications for extremely high-risk conjunctions or significant maneuvers, and post-conjunction documentation when close approaches occur. Maintain detailed conjunction event logs for audit purposes.

Q: What is conjunction assessment for satellites?

A: Conjunction assessment is the process of analyzing whether a satellite’s orbit will bring it dangerously close to another object (satellite, debris, or rocket body) and determining if a collision avoidance maneuver is required. This involves receiving CDMs from screening services, evaluating probability of collision, and coordinating with affected operators.

Q: What if my CubeSat cannot maneuver?

A: Non-maneuverable satellites must still perform conjunction screening and coordination. When CDMs are received, inform the other operator that your satellite cannot maneuver, allowing them to decide whether to maneuver their satellite. The FCC expects non-maneuverable satellites to minimize conjunction risk through careful orbital selection and to maintain screening processes even without maneuver capability.

Q: At what probability of collision should I maneuver?

A: Industry best practice suggests maneuvering at Pc > 1e-4 (1 in 10,000) and beginning active monitoring at Pc > 1e-5 (1 in 100,000). However, operators should establish internal policies considering miss distance, relative velocity, tracking uncertainty, and object size. Document your thresholds and apply them consistently to demonstrate systematic compliance.