Rocket Development¶

Last updated: 2026-05-29

Focus: avionics, flight software, and the systems engineering side — not propulsion chemistry.

Recent Finds¶

IREC 2026 Status — Video Deadline Today, Final Hardware Phase Begins (ESRA, 2026-05-29)¶

Status as of 2026-05-29: The short video submission deadline for the IREC livestream is today (May 29, 5:00 PM CT); the Team Video Challenge submission window closes tomorrow May 30 per ESRA documentation. All documentation gates are now closed — no further technical submissions remain. The competition enters its final hardware integration phase: items allowed at Spaceport Midland from June 11; Certification Kit Build Day June 13; Certification Launch Day June 14; competition June 15–20 Midland TX. For avionics teams this is the critical window for ground testing, FRAM data logging checks, arming switch continuity verification, and pyro circuit qualification before shipping hardware.

IREC 2026 Status — Short Video Submission Due Tomorrow (May 29), Competition in 18 Days (ESRA, 2026-05-28)¶

Status as of 2026-05-28: PR3 (Progress Report 3) closed May 20 — all 175 teams' avionics documentation locked. ESRA range safety reviewers are processing. Tomorrow (May 29 at 5:00 PM CT) is the short video submission deadline for the IREC livestream — a media deliverable, not a technical gate. After that, all remaining activity is hardware operations: items allowed at Spaceport Midland starting June 11; Certification Kit Build Day June 13; Certification Launch Day June 14; competition June 15–20 Midland TX. The Team Video Challenge submission window officially closes May 30 per ESRA documentation. For avionics teams: all documentation gates are now closed — the phase from here to June 11 is final hardware integration, system testing, and packing.

IREC 2026 Status — Short Video Submission Due May 29, Competition in 21 Days (ESRA, 2026-05-25)¶

Status as of 2026-05-25: PR3 (Progress Report 3) closed May 20 — all 175 teams' avionics documentation locked. ESRA range safety reviewers are processing submitted apogee-detection, dual-deploy, and FTS documentation. Next milestone: May 29 at 5:00 PM CT — short video submission deadline for the IREC livestream (teams submit a short showcase video; this is a media deliverable, not a technical submission). After that, the competition moves entirely to hardware operations: items allowed at Spaceport Midland starting June 11; Certification Kit Build Day June 13; Certification Launch Day June 14; competition June 15–20 Midland TX. Complete June timeline: June 11 (item pickup at Midland warehouse), June 13 (certification kit build day), June 14 (certification launch + hybrid/two-stage pad setup), June 15–16 (check-in + opening ceremony + safety reviews at Horseshoe Pavilion), June 17–20 (launch operations, four days), June 20 (awards ceremony + live video challenge deadline).

AIAA ASCEND 2026 Concludes — Aerospace Corporation Space Transformation Track Day 3 (AIAA / Aerospace Corp, May 21, 2026)¶

Status as of 2026-05-21: AIAA ASCEND 2026 completed today in Washington DC — all three days concluded. Day 3 (May 21) featured the Aerospace Corporation's inaugural Space Transformation Track, an action-oriented program with Strategic Innovation Sandbox roundtables focused on accelerating national security space acquisition, aligning investments with national priorities, and building innovation ecosystems. The NISAR Pickering Lecture was delivered by Paul A. Rosen (NASA JPL), detailing early findings from the NASA-ISRO Synthetic Aperture Radar mission. The PR3 window closed yesterday (May 20, 5:00 PM CST) — all 175 teams' avionics documentation is now locked. ESRA has departed Booth 306; the competition moves to hardware-only operations. Next milestone: late-phase submission May 29. Items ship to Spaceport Midland from June 11; competition June 15–20 Midland TX.

IREC 2026 PR3 Deadline Day — AIAA ASCEND Innovators Day (ESRA / AIAA, May 20, 2026)¶

Status as of 2026-05-20: Progress Report 3 (PR3) submission window closes today at 5:00 PM CST — the final engineering documentation gate for all 175 IREC 2026 teams. PR3 covers apogee detection logic, dual-deploy architecture, FTS compliance, and pyro channel documentation; range safety reviewers began processing earlier submissions throughout the week. Simultaneously, AIAA ASCEND 2026 Innovators Day is underway in Washington DC (Day 2 of 3) — ESRA remains at Booth 306 for any last-minute team Q&As before the 5pm lock. After today: the competition moves entirely to hardware — items shipped to Spaceport Midland from June 11, competition June 15–20. The next major documented milestone is the late-phase submission (May 29). ASCEND completes May 21 (Aerospace Corporation Space Transformation Track).

AIAA ASCEND 2026 In Progress — ESRA at Booth 306, PR3 Due Tomorrow (ESRA / AIAA, May 19, 2026)¶

Status as of 2026-05-19: AIAA ASCEND 2026 is underway today in Washington DC (May 19–21). NASA Administrator Jared Isaacman opened the conference this morning (8:00 AM). ESRA is exhibiting at Booth 306 — the final in-person opportunity for IREC 2026 teams to engage directly with ESRA leadership on range safety Q&As before the PR3 deadline tomorrow, May 20 at 5:00 PM CST. ASCEND runs concurrent programming tracks: Investors Day (May 19), Innovators Day (May 20), and the Aerospace Corporation Space Transformation Track (May 21), with 2,000+ participants and 130+ sessions. The timing of ESRA's ASCEND presence the day before PR3 lock-in is intentional: teams attending the conference can walk to Booth 306 for a final range safety Q&A, then submit their apogee detection architecture and dual-deploy documentation the following morning. Competition timeline: items to Spaceport Midland from June 11; competition June 15–20 Midland TX. The 175-team field is now finalizing avionics documentation across all categories including the new 45,000-ft two-stage class.

IREC 2026 Status Update — Registration Closed May 15, PR3 Window Open Through May 20 (ESRA)¶

Status as of 2026-05-17: Registration closed May 15, 2026 at 5:00 PM CST as scheduled — all 175 team identities are now locked. Progress Report 3 (PR3) window remains open through May 20, 2026 at 5:00 PM CST — T-3 days from today. PR3 is the substantive avionics/safety documentation submission (apogee detection logic, dual-deploy architecture, FTS compliance, pyro channel documentation); range safety reviewers are actively reviewing submitted reports. ESRA at AIAA ASCEND May 19–20 (Washington DC, Booth 306) — one day before the PR3 deadline, the last direct-contact opportunity for teams to resolve range safety Q&As before documentation locks. Items can be shipped to Spaceport Midland starting June 11; competition June 15–20. The May 20 PR3 deadline is the final engineering decision gate for all teams.

The May 10 ESRA newsletter is the final pre-deadline bulletin before the May 15 registration closure. Key updates: (1) Registration closes May 15, 2026 at 5:00 PM CST — the final hard deadline for all rocketeer, volunteer, and sponsor/vendor registration. (2) Progress Report 3 submission window is now open through May 20, 2026 at 5:00 PM CST — teams can begin submitting. (3) Drone ban confirmed: "No student, sponsor, or spectator UAS (Drones) will be permitted at the Horseshoe Pavilion, Spaceport Midland launch site, or the Bush Center during the 2026 IREC" — relevant for avionics teams who planned ground-to-ground video documentation using UAV platforms; imagery must instead come from ground cameras and onboard telemetry. (4) ESRA will exhibit at AIAA ASCEND 2026 at Booth 306 (Washington DC, May 19–20) — one day before the PR3 deadline, providing a final opportunity for direct engagement with ESRA leadership on range safety Q&As. Technical Report submissions have closed. Status: today (May 12) is T-3 days to registration closure; T-8 days to PR3 deadline. For avionics teams: the PR3 documentation window being open now means range safety reviewers can begin reviewing apogee detection logic, dual-deploy documentation, and FTS compliance submissions — teams can receive feedback before the May 20 lock.

ESRA at AIAA ASCEND 2026 — May 19–21, Washington DC (ESRA)¶

ESRA volunteers and selected IREC 2026 teams will represent the competition at the AIAA ASCEND 2026 conference (May 19–21, Washington DC), briefing conference attendees on what it takes to compete in IREC and on volunteering opportunities. The timing is notable: AIAA ASCEND falls the day before the Progress Report 3 deadline (May 20), making this a dual-purpose window — ESRA promotes the competition to the professional aerospace community while teams finalize their avionics documentation submissions. AIAA ASCEND is the primary annual early-career and academic aerospace conference; IREC's presence there reflects the competition's role as a pipeline between university rocketry and the professional aerospace workforce. Any teams attending ASCEND can engage directly with ESRA leadership on range safety Q&As before their PR3 locks.

IREC 2026: Video FRSR Window Open — Completion Deadline May 15, PR3 Due May 20 (ESRA, May 2026)¶

As of May 8, IREC 2026 is entering its highest-intensity pre-competition review window. Video Flight Readiness Safety Review (FRSR) submissions were due May 1; ESRA Safety Reviewers are now completing reviews with a completion deadline of May 15, 2026. A further late-phase submission closes May 29. This creates a cascading documentation/hardware lock for avionics teams: May 15 review completion means range safety feedback arrives just before the May 20 Progress Report 3 submission — potentially forcing last-minute avionics architecture changes. Teams in the 45,000-ft two-stage category face the most complex documentation: dual-sensor apogee detection (IMU + baro with transonic suppression), staging sequencing state machine, and FTS compliance must all be specified in the PR3 with enough detail for range safety to approve them. With items allowed at Spaceport Midland from June 11 and competition June 15–20, the May 15–20 window is the final engineering decision gate for all 175 registered teams.

The April 28 ESRA newsletter clarifies the final submission cadence for IREC 2026 with precise deadlines: team registration closes May 15 at 5 PM CST (not the TRP — registration itself, including any team composition changes), and Progress Report 3 is due May 20 at 5 PM CST. These are distinct submissions: registration locks team identity, while PR3 is the substantive avionics and safety documentation artifact. A Volunteer Town Hall was held April 30 for logistics Q&A (Zoom). New Bronze Sponsor: Karman Space & Defense joins the IREC 2026 sponsor list. Volunteer Spotlight: Mohi Khan (Director of Launch Operations), IREC competitor since 2012, transitioned to volunteering in 2022. The registration/PR3 distinction matters for avionics teams: the May 15 registration deadline is administrative, while the May 20 PR3 is when range safety reviewers first see the avionics architecture documentation — including apogee detection logic, pyrotechnic channel count, FTS compliance, and GPS/telemetry validation plan. For two-stage teams targeting 45,000 ft, the PR3 is the first formal review of staging sequencing and IMU+baro fusion implementation.

ASU SEDS Builds First Hybrid Rocket in University History for IREC 2026 (Arizona State Press, April 2026)¶

The SEDS Rocketry Division at Arizona State University is flying the first student-researched and developed hybrid rocket in ASU history at IREC 2026 (Midland, June 15–20). The decision to enter the hybrid category was deliberate — lower competition pool at higher technical difficulty. Avionics lead Ava Prechel (junior, aerospace engineering) describes the reality of competing under IREC's monthly regulation updates: the avionics bay was printed six times across the semester, requiring repeated rewiring to stay current with each regulatory revision. This is the most concrete recent example of IREC's regulation update cadence imposing real avionics rework costs — every hardware-change cycle in DTEG revisions cascades directly into enclosure geometry, connector routing, and pyro channel layout. The hybrid propulsion challenge compounds this: no prior institutional knowledge exists at ASU, making the project an exercise in first-principles avionics integration under a changing regulatory target. Architecturally, hybrid rocket avionics require oxidizer valve actuation control (absent in solid motor FCs), oxidizer-side pressure sensing, and feed system sequencing — expanding the pyro channel and analog input requirements beyond standard HPR flight computers. For any university team building avionics for hybrid motors: hybrid-specific valve sequencing is the primary differentiator from solid avionics, requiring at least one additional output channel and a pre-pressurization state machine before ignition.

IREC 2026 Final Pre-Competition Phase — Multiple May Milestones (ESRA, April 2026)¶

With 175 teams confirmed from 22 countries, IREC 2026 is now in its final pre-competition preparation phase. The submission cadence through May is: May 1 (early deliverables, now imminent), May 15 (midpoint package), May 20 (Team Registration Package — the primary technical submission including flight data, safety documentation, and avionics validation artifacts), and May 29 (final late-phase submission). Items shipped to Midland can be received from June 11, with the competition June 15–20, 2026 at Spaceport Midland, TX. The month of May represents the maximum-intensity avionics verification period for all teams: static fire verifications, pyro continuity checks, GPS/telemetry range validation, and the formal documentation package that range safety reviews before permitting flight. For teams in the 45,000-ft two-stage category (introduced this year), the May 20 TRP is where dual-sensor apogee detection logic (IMU + baro, with transonic suppression), staging sequencing, and FTS compliance must be documented. Combined with the final town hall recording (April 16, available on ESRA's channel), May is the critical window for teams to resolve range safety Q&As before submission locks in their avionics architecture.

BPS.Space Mach 1.8 Premature Deployment — Boolean Logic Failure in Flight-Critical FSW (Hackaday, January 2026)¶

A BPS.Space flight at approximately Mach 1.8 suffered a premature parachute deployment that severed Kevlar inter-section connectors. Root cause: a boolean logic inversion in an untested software modification intended to improve altitude estimation. The fix was meant to switch from barometric sensing (unreliable above transonic speeds due to shockwaves corrupting static ports) to accelerometer-based velocity integration during boost — but an inverted conditional caused accelerometer velocity to be passed to the barometric path instead, producing a negative velocity reading that the apogee-detection logic interpreted as post-apogee descent. Hardware: AVA flight computer uses NXP Kinetis K20 (Teensy 3.2) as main FC, Microchip SAM D21 for navigation, second SAM D21 for telemetry, Bosch BNO055 + Rohm KX134 (±64 g) IMU. The failure mode — untested code modification + transonic sensor inversion — is a direct case study for: (a) mandatory end-to-end sensor-path integration testing before flight, and (b) designing Mach-immune event detection that gates apogee detection on accelerometer velocity crossing zero rather than barometric pressure derivative. Directly applicable to any IREC team implementing dual-sensor altimetry above 10,000 ft.

HPR Rocket Flight Computer (SparkyVT / Teensy 4.1): Mach-Immune Apogee Detection at 1600 Hz (GitHub)¶

SparkyVT's open-source HPR flight computer on Teensy 4.1 is one of the reference implementations for Mach-immune event detection in 2026. Key specs: 1,600 samples/second IMU + baro logging, 4 programmable pyro outputs, two-stage and air-start capable with tilt-sensing safety lockout, GPS and 433/915 MHz telemetry. Mach-immune logic: gates apogee detection on integrated accelerometer velocity crossing zero rather than barometric pressure derivative — preventing false apogee triggers in the transonic regime where dynamic pressure corrupts static port measurements (the exact failure mode in the BPS.Space incident). Supports BMP280/388, MS5607, ICM-42688, LSM6DSO32 IMUs via configurable sensor abstraction. This is the community benchmark reference most IREC teams compare their SRAD avionics against — the CATS platform (already in this wiki) and the Carlson platform are the other two main open-source options.

The April 12 ESRA newsletter confirmed two updates: Blue Origin returns as an IREC 2026 sponsor (having previously supported the competition), and the penultimate community town hall took place April 16, 2026 at 7pm CT (recordings available). Team and Rocketeer fees deadline has passed (April 10, 2026). The registration process is in its final stage before the Team Registration Package submission deadline on May 20. The Blue Origin sponsorship is significant beyond branding: it signals that New Space companies view university rocket competitions as a talent pipeline — the same dynamic that brought Aerojet, L3 Technologies, and Northrop Grumman into IREC sponsorship. For avionics teams at IREC 2026: the final town hall recordings (available on ESRA's channel) typically contain the most specific technical Q&A on range safety requirements for dual-deploy, FTS systems, and telemetry validation — directly relevant to flight computer design decisions in the weeks before the May 20 submission deadline.

IREC 2026 Registration Update — 175 Teams, Rocketeer Fees Updated April 10 (ESRA, April 2026)¶

IREC 2026 (Spaceport Midland, June 15–20) has 175 accepted teams from 22 countries confirmed. Rocketeer fees were updated April 10, 2026 — the most recent change to the official event page. Team Registration Package submission opened April 1; final deadline May 20, 2026. Monthly community townhalls continue on the 3rd Thursday at 7pm Central (recordings available). The 45,000-ft two-stage category remains the defining new avionics challenge for 2026: above 40,000 ft, barometric apogee detection becomes unreliable — IMU+baro sensor fusion with transonic suppression, GNSS continuity through the tropopause, and staging event sequencing are all avionics requirements this category mandates. With 175 teams, IREC 2026 is the largest community-scale flight test of university avionics stacks in the world.

Indonesian Biak Spaceport RPP: Still Unsigned — Jakarta Post Calls It a "Legal Vacuum" (Jakarta Post Opinion, April 16, 2026)¶

As of April 16, 2026, Indonesia's Draft Government Regulation (RPP) on Spaceport Operations has still not received presidential enactment — despite completing inter-ministry harmonization weeks ago. A Jakarta Post opinion piece published April 16 explicitly frames the situation as a "legal vacuum stalling" the Biak National Spaceport program, calling for urgent regulatory resolution. BRIN is simultaneously pursuing PSN (National Strategic Project) designation for Biak within the 2025–2029 national development plan — which would unlock priority funding and expedited land-clearing. The editorial pressure is significant: it signals that the regulatory delay is becoming publicly visible and politically costly, which may accelerate the presidential signature timeline. Until the RPP is signed, no construction can legally begin at Biak and private/university rocket programs remain in a permitting grey zone.

Curtiss-Wright + Green Hills / DDC-I: Safety-Certified COTS Avionics Computing Stack (Jan–Feb 2026)¶

In January–February 2026, Curtiss-Wright announced two COTS avionics computing solutions pairing its SOSA-aligned V3-1222 3U VPX Intel Core i7 processor card with safety-certified RTOS software: one with Green Hills INTEGRITY-178 tuMP (FACE-certified for US DoD avionics interoperability) and one with DDC-I Deos (DO-178C DAL-A certifiable). Both target flight control computers, digital cockpit systems, and autonomous flight control. The 3U VPX form factor is the current standard for federated avionics architectures — compatible with OpenVPX backplanes and standard chassis from multiple vendors. Why it matters for rocket avionics: While aimed at defense/commercial aviation, this stack represents the current leading edge of certifiable COTS computing for flight-critical applications. The FACE-certification approach (Future Airborne Capability Environment) provides a portable software architecture allowing the same avionics application to run on different hardware platforms without re-certification — directly applicable to launch vehicle programs moving from custom avionics hardware toward certifiable COTS platforms. The DDC-I Deos variant is particularly relevant: Deos's time+space partitioning (ARINC 653-compliant) allows hosting multiple avionics applications with different criticality levels (flight control at DAL-A, telemetry at DAL-C) on a single processor, reducing avionics bay complexity.

IREC 2026 Selected Teams Announced + DTEG v1.0 Published (ESRA, 2026)¶

ESRA published the selected teams for IREC 2026 and confirmed the event moves to Spaceport Midland (not Spaceport America) for 2026, June 15–20. The 2026 event introduces a 45,000-foot two-stage category (new for 2026) and a 100,000-foot waiver — both requiring avionics capable of staging events, GNSS continuity at extreme altitude, and telemetry solutions operating across significantly longer time-of-flight profiles. The Design, Test & Evaluation Guide (DTEG v1.0), published October 2025, is the reference document for what avionics teams are designing to right now. Avionics requirements in DTEG drive flight computer architecture (pyro output count, sensor fusion requirements, GPS/APRS configuration), recovery system design (dual-deploy altitude profiles for each category), and telemetry (real-time position to range safety). The 45,000-ft category is the key capability step: above ~40,000 ft, barometer-only apogee detection becomes unreliable (above the troposphere, pressure gradients are shallow), making IMU+barometer sensor fusion with proper transonic suppression non-optional.

CATS: Open Hardware/Software HPR Flight Computer + Quaternion AHRS Finding (catsystems.io, 2026)¶

CATS (Control And Telemetry Systems) is a fully open hardware/software HPR flight computer joining SparkyVT and the Carlson platform as the main open-source avionics options in 2026. CATS is notable for fully open PCB files, firmware, and ground station software — reproducible from scratch by any university team. Community benchmarking across these platforms has produced an important sensor fusion finding: quaternion-based AHRS consistently outperforms classical EKF under the non-constant-acceleration flight profile of HPR rockets. The root cause is that EKF relies on linearization around a nominal trajectory — HPR rockets violate this assumption during boost (10-20g sustained acceleration), the transonic phase (rapidly changing dynamic pressure), and staged events. Quaternion AHRS (via the Python AHRS library's Madgwick/Mahony implementations) handles these nonlinearities more robustly with lower tuning complexity. Practical implication: for any university team designing sensor fusion for sounding rockets or sub-orbital vehicles, quaternion AHRS is the current community-preferred starting point over hand-tuned EKF for attitude determination during boost.

BRIN Biak Spaceport Cross-Sector Synergy Push — Draft RPP Cleared Harmonization (Indonesia Business Post, 2026)¶

BRIN Head Arif Satria convened a cross-sector coordination meeting confirming that the Draft Government Regulation (RPP) on Spaceport Operations has completed inter-ministry harmonization and is ready for enactment — the immediate follow-on to the Jan 2026 seasia.co report. BRIN is simultaneously formulating derivative regulations so that once the RPP is enacted, site designation and land-clearing at Biak can begin immediately. The national space master plan is being extended to 2045. Satria's explicit warning against "overlapping authorities" signals a recognized coordination risk: multiple agencies (BRIN, Ministry of Transportation, Ministry of Defense) have overlapping jurisdiction over launch licensing, and the derivative regs must resolve this before private or university programs have a functional permitting path. Institutional restructuring via coordination with the Ministry of Administrative and Bureaucratic Reform is underway. The updated open question: will the RPP reach presidential signature before mid-2026, enabling the 2026 land-clearing milestone?

IREC 2026: 175 Teams, Midland Texas June 15–20, University Avionics at Scale (ESRA / AIAA)¶

The 2026 International Rocket Engineering Competition (IREC) will host 175 accepted teams from 22 countries at Midland International Air & Space Port, Texas, June 15–20, 2026. Target altitude categories: 10,000 ft and 30,000 ft with payload >2 kg. IREC is the largest annual showcase of university-built avionics stacks flying on solid and hybrid motors — the competition generates a high density of real flight data on custom flight computers, EKF implementations, dual-deploy recovery systems, and telemetry architectures, most of which appears in post-competition technical reports. For avionics development context: IREC 2026's 175-team scale (up from ~130 in 2023) reflects the growing pool of university programs building and flying custom flight computers, making it a useful benchmark for the state of the art in non-commercial rocketry avionics. The Design, Test & Evaluation Guide (DTEG v1.0) is publicly available and specifies avionics, safety, and range requirements.

The E-Rocket: Low-Cost PX4+ROS 2 Testbed for TVC GNC Validation (arXiv:2512.06535)¶

Purpose-built low-cost rocket testbed for validating GNC algorithms based on Thrust Vector Control, using commercially available components and 3D printed parts. Hardware: Pixhawk 6C Mini flight computer (PX4 autopilot for sensor fusion, estimation, and actuator commanding) + Raspberry Pi 5 companion computer (Ubuntu + ROS 2 for GNC algorithm execution, logging, and comms) + a pair of contra-rotating DC brushless motors on a servo-actuated gimbal for TVC. The dual-computer split is the architectural key: PX4 handles the tight real-time sensor loop while ROS 2 provides modularity for swapping GNC algorithm implementations without hardware changes — enabling rapid algorithm iteration. Validated in an indoor motion-capture arena with a baseline PID trajectory tracking controller. The EKF is PX4-native (built into the autopilot stack). Practical significance: this is the lowest-cost, highest-reproducibility entry point for TVC GNC development — cheaper than any commercial testbed, and software-in-the-loop compatible before any physical hardware is built. Directly complements AeroVECTOR (3DOF simulation) already in this wiki: AeroVECTOR for design/simulation, E-Rocket for low-cost physical validation.

LoRa Drone Repeater for HPR Telemetry: DIY Builds and S5 Copilot (Rocketry Forum / Tindie, 2026)¶

Drone-carried LoRa repeater builds for high-power rocketry have matured from concept to practiced technique. A self-contained Arduino Mini Pro + LoRa module unit can be airlifted by drone to extend telemetry range beyond terrain obstructions — directly solving the "landed behind the ridge" recovery problem. Commercially, the SpecFive S5 Copilot (https://www.tindie.com/products/specfive/s5-copilot-meshtastic-repeater-for-drones-heltec/) is a Meshtastic-based LoRa repeater purpose-built for drone integration (Heltec chipset), enabling mesh networking between rocket, drone, and ground. Semtech's LR1121 chip adds S-band satellite fallback alongside 900 MHz terrestrial LoRa — directly relevant for extreme-altitude or remote launches where terrestrial LoRa range is insufficient and satellite SMS backup is needed. Architecture pattern: drone launches at T+burnout, ascends to 300–500 ft AGL above terrain, provides relay coverage for descent/landing phase.

APRS vs. LoRa for Rocket Recovery Telemetry: Practical Comparison (N3VEM / Rocketry Forum)¶

The community consensus has crystallized on the APRS vs. LoRa decision for rocketry. APRS (144.390 MHz, US): best for recovery because the iGate infrastructure provides nationwide coverage — a landed rocket transmitting APRS position will be received by an iGate even if you've driven out of range. Proven in real flights. LoRa (900 MHz): best for in-flight telemetry — 5,000+ m range at 30 mW, ~1.5s packet interval, supports custom high-rate sensor data, but requires a dedicated ground receiver at the launch site. No infrastructure dependency. The LoRa-APRS hybrid (https://www.lora-aprs.info/) bridges both by encoding APRS packets over LoRa modulation — received by both LoRa gateways and traditional iGates via gateway bridging. Recommended architecture for HPR: LoRa primary telemetry (full sensor stream) + APRS secondary recovery beacon (position only, iGate fallback).

BRIN Biak Spaceport RPP: Draft Government Regulation Enters Final Enactment Stage (Indonesia, Q1 2026)¶

As of Q1 2026, Indonesia's Draft Government Regulation (RPP) on Spaceport Operations has completed inter-ministry harmonization and awaits final presidential enactment — the most significant Indonesian space regulatory development in years. The RPP directly enables BRIN to begin land-clearing and construction at the Biak National Spaceport in 2026, which was the immediate practical goal of the regulatory push. Biak (West Papua) is a near-equatorial site with strategic launch geometry advantages for equatorial and SSO missions. A parallel UNAIR-BRIN working group is focused on rocketry licensing and certification standards meeting international norms. What changes when the RPP is enacted: private and university rocket programs currently operating in a legal grey zone will have a defined permitting path for the first time since LAPAN's dissolution in 2021. The RPP does not yet resolve the MTCR import control problem (Indonesia is not an MTCR member), but it creates the domestic legal infrastructure that is the prerequisite for any international engagement on that issue.

Indonesian Rocketry Regulation Post-LAPAN: BRIN Regulatory Gap (UNAIR / BRIN, 2025–2026)¶

LAPAN was dissolved into BRIN (National Research and Innovation Agency) in September 2021, but no new supervisory regulatory structure for experimental rocketry was created — leaving a regulatory gap with no licensing/certification framework, weak inter-agency coordination, and no derivative regulations for private or university rocket programs. Indonesia also cannot import certain rocket propellants or launch vehicles without joining MTCR (Missile Technology Control Regime), which it has not done, creating export control complications for procuring motors or propellant chemistry from MTCR member countries. BRIN's active priority is now drafting derivative regulations to fill this gap, but no final framework has been published as of April 2026. Practical consequence: Indonesian experimental rocketry programs (university clubs, private) operate in a legal grey zone — tolerated but not formally licensed. The BRIN RX-series sounding rocket program continues under institutional auspices, but private/university experimental programs lack a clear permitting path.

Active Fin Stabilization Flight Computer — NAU EE Capstone 2026 ¶

Northern Arizona University EE capstone documents a complete active fin stabilization system: Arduino Mega FC, IMU for angular velocity/orientation, barometric altimeter. A PID controller adjusts movable fin angles in real-time to generate corrective aerodynamic torques. Two flight test objectives: deliberate induced-rotation (spin to 100 RPM, reverse, stop) and active null-stabilization (hold roll rate near 0 RPM throughout flight). Architecture deliberately prioritizes simplicity — no TVC, no cold-gas RCS — making it a practical entry point vs. motor-gimbal designs with more complex failure modes. The PID-over-IMU architecture is directly transferable to RP2040 or STM32-based custom flight computers at smaller form factors. Worth studying as the minimal viable active stabilization reference design before scaling to TVC.

AeroVECTOR: Open-Source 3DOF Simulator for TVC and Fin-Control Rockets (GitHub)¶

Open-source 3DOF rocket simulator purpose-built for designing and tuning active control systems — TVC, active fin control, and guided parachute deployment. Computes subsonic aerodynamic parameters, integrates full equations of motion, models non-linear actuator dynamics (critical for realistic servo simulation), and supports Software-in-the-Loop workflows so firmware can be tested in simulation before physical flight. Already forked by the Elara Aerospace student team. Fills the critical gap between OpenRocket (passive stability simulation) and actual flight: it provides the control-loop verification environment that neither OpenRocket nor generic flight simulators offer. The non-linear actuator dynamics model is the key feature for validating whether servo speed and stall torque are adequate for expected disturbance magnitudes before committing to a flight attempt.

SparkyVT HPR Rocket Flight Computer: 1600 sps, Mach 2.3, 250+ Flights (GitHub)¶

The most mature open-source HPR flight computer project: Teensy 4.1-based (ARM Cortex-M7 @ 600 MHz), runs at 1600 samples/second for all sensor channels simultaneously. Features: 4 programmable pyro outputs, Mach-immune apogee detection (barometer-only apogee detection has false positives during transonic phase — this system suppresses them), air-start and two-stage support, tilt-sensing safety inhibit (won't fire pyros if rocket is off-axis post-apogee). Flight-tested on 250+ flights including M and N class motors, reaching 34,000 ft AGL at Mach 2.3. The PCB fits in a 38mm tube coupler. Practical for high-power club rocketry through experimental class. Sensor fusion architecture: complementary filter for altitude (IMU + barometer), GPS for position logging post-flight (not used real-time for apogee detection).

Georgia Tech GTXR Two-Stage Sounding Rocket: EKF for GNSS Lockout (AIAA 2024)¶

University-level sounding rocket avionics design using Extended Kalman Filter (EKF) for state estimation — specifically addressing GNSS lockout (GPS drops under high-G and supersonic flight). Modular avionics: separate boards for power, compute, and RF with a CAN bus backbone. EKF fuses 6-DOF IMU + barometer during GPS blackout intervals. Key lesson: GPS alone is insufficient above Mach 0.8 — the EKF must be tuned to handle the transonic barometer pressure anomaly near Mach 1.

LeLaR: DRL Attitude Control Demonstrated In Orbit — Implications for Rocket Avionics (arXiv 2512.19576)¶

While primarily a satellite ADCS result, LeLaR's Sim2Real success has direct implications for advanced rocket avionics: a deep reinforcement learning controller trained purely in simulation controlled InnoCube's reaction wheels in orbit on Oct 30, 2025 — without any in-flight fine-tuning. The training randomized over inertia uncertainty, actuator noise, and disturbances. For rocket avionics, this opens the door to DRL-based attitude controllers for TVC (thrust vector control) or active fin stabilization systems — domains where hand-tuning EKF + PID stacks for each new vehicle configuration is expensive. Key open question: can Sim2Real transfer survive the far more violent dynamics of boost phase (>5G, vibrational noise, propellant slosh) compared to the relatively benign orbital environment?

IREC 2026: Progress Report 3 Deadline Extended to May 20 — 175 Teams Confirmed (ESRA, April 2026)¶

ESRA published schedule updates (effective March 20, 2026) moving the Progress Report 3 deadline from April 10 to May 20, 2026, giving teams an additional 40 days for documentation. The 2026 IREC (June 15–20, Midland Texas) now has 175 confirmed teams — the largest IREC field to date. The 45,000-ft two-stage category is new for 2026, raising the engineering bar significantly for avionics: two-stage events require staging detection, ignition sequencing, and dual-phase EKF state management at separation — capabilities well beyond standard single-deployment recovery systems. For the avionics community watching what architectures will dominate: the STM32H7/RP2040 dual-processor pattern (fast state estimation + secondary safe-arm controller) is the competitive standard; new entrants are integrating model-based state estimation from AeroVECTOR-class simulators directly into flight software. The Blue Origin sponsorship return (April 12 ESRA newsletter) signals commercial endorsement of the program.

Rocket Anatomy (Systems View)¶

┌─────────────────────────────┐
│         Payload / Nosecone  │ ← satellite, experiment, recovery bay
├─────────────────────────────┤
│         Avionics Bay        │ ← FC, IMU, GPS, barometer, RF, power
├─────────────────────────────┤
│         Propellant Tanks    │ ← liquid: oxidizer + fuel / solid: grain
├─────────────────────────────┤
│         Engine / Motor      │ ← thrust generation
└─────────────────────────────┘

Avionics¶

The brain of the rocket. Handles state estimation, event detection, and recovery.

Flight Computer (FC)¶

Responsibilities: 1. State estimation — fuse IMU + GPS + barometer → position, velocity, altitude, orientation 2. Event detection — apogee, burnout, staging (for multi-stage) 3. Recovery sequencing — deploy drogue (fast) then main parachute (slow) at right altitudes 4. Telemetry — broadcast data to GCS in real-time 5. Abort / safe mode — inhibit pyrotechnics if criteria not met

Sensors¶

Sensor	Purpose	Typical part
IMU (6/9-DOF)	Accel + gyro (+ mag)	ICM-42688-P, BMI088
Barometer	Altitude (pressure)	MS5611, BMP390
GPS	Position + velocity	u-blox M10, ZED-F9P (RTK)
Pyro continuity	Check e-match integrity	Simple ADC measurement

Sensor fusion: Extended Kalman Filter (EKF) or Complementary Filter. GPS alone is too slow (1–10 Hz) and drops under high acceleration. IMU alone drifts. Fusion gives best-of-both.

Open Source Flight Computers¶

Project	Language	Notes
OpenRocket	Java	Simulation only — not a flight computer
AltOS / TeleMetrum	C	Altus Metrum — mature, used widely in amateur rocketry
RAVEN	C	Featherweight Rocketry — certified recovery FC
Odyssey	C++	University rocketry standard
Custom STM32/RP2040	C/C++	DIY, educational projects

Recovery System¶

Dual-deploy is standard for high-power rocketry: 1. Drogue — small chute at apogee. Slows from terminal velocity but still fast. 2. Main — large chute at lower altitude (~150–300m AGL). Slow landing.

Triggered by barometer detecting pressure increase (descent detected) + altitude threshold.

Ejection charges (black powder) or CO2 systems physically separate sections and deploy chutes.

Redundancy: two independent flight computers, each with independent e-match channels.

Flight Software¶

State Machine¶

IDLE → ARMED → BOOST → COAST → APOGEE → DROGUE → MAIN → LANDED

Each state transition has criteria: - ARMED→BOOST: accelerometer > 3g for > 0.1s - BOOST→COAST: accelerometer < 0g (burnout) - COAST→APOGEE: vertical velocity crosses zero (from IMU/baro fusion) - APOGEE→DROGUE: fire pyro channel 1 - DROGUE→MAIN: barometer altitude < threshold AGL - MAIN→LANDED: velocity < 1 m/s for > 5s

Safety Inhibits¶

Pyrotechnic systems should never fire unless ALL conditions met:

def can_fire_drogue():
    return (
        state == APOGEE and
        altitude > MIN_SAFE_ALTITUDE and  # not on pad
        time_since_launch > MIN_FLIGHT_TIME and
        continuity_drogue_ok and
        armed_by_operator
    )

Telemetry Protocols for Rocketry¶

LoRa (433/915 MHz) — long range, low data rate, line-of-sight 20–30 km
APRS (144.390 MHz, US) — AX.25 packet radio, nationwide receiver network
2.4 GHz custom — higher bandwidth, shorter range
Iridium SBD — satellite telemetry, works anywhere (GPS + position beacon)

Typical telemetry packet: timestamp, altitude, velocity, GPS lat/lon, temperature, voltage, state.

Launch Systems & Infrastructure¶

Categories¶

Class	Altitude	Mass	Examples
Model	<500m	<125g motor	Estes
High Power (HPR)	1–30 km	H–O motors	NAR/Tripoli certified
Experimental	30–100 km	Research motors	UKRA, university programs
Sounding Rocket	100–1500 km	Professional	NASA Black Brant, VSB-30
Orbital	200+ km	Tons	SpaceX, RocketLab, ISRO

Range Safety¶

For any experimental/university launch: - Flight termination system (FTS) — ground command to destroy or neutralize vehicle - Range clearance — coordinate with local aviation authority (NOTAM) - Exclusion zone — keep personnel at safe distance (debris trajectory calculation) - Telemetry — real-time position for safety officer to authorize flight termination

PropulsionTypes (Software Perspective)¶

Type	Controllability	Restart	Notes
Solid	None once ignited	No	Simple, reliable, most amateur rockets
Cold gas	Throttleable	Yes	N₂ or CO₂, low Isp, used for RCS
Liquid bipropellant	Throttleable	Yes	Complex, high Isp, SpaceX/RocketLab
Hybrid	Partially	Limited	Solid fuel + liquid oxidizer (LOX/N₂O)

For software: liquid engines expose the most control surface — injector valves, turbopumps, gimbal actuators, all with feedback loops.

Key Organizations & Programs¶

NASA Student Launch — annual competition, HPR, universities worldwide
Spaceport America Cup — largest intercollegiate rocketry competition
IREC / SAC — 10k and 30k ft APOGEE challenge
LAPAN/BRIN (Indonesia) — national rocketry research (RX series sounding rockets)
Reaction Engines — SABRE engine (air-breathing/rocket hybrid)
RocketLab — Electron (small orbital launch vehicle), open-source mindset, Neutron upcoming

Open Questions¶

What's the state of propellant-free propulsion (electrodynamic tether, solar sail) for orbit raising in small sats?
Can RP2040/STM32H7 handle real-time EKF at 1 kHz on a flight computer without RTOS?
How does SpaceX Starship's full-flow staged combustion affect the propulsion design space for new entrants?
Indonesian RPP for Biak Spaceport: presidential signature still pending as of April 17 — Jakarta Post April 16 editorial calls it a "legal vacuum." Will PSN designation accelerate?
IREC 2026 (June 15–20): 175 teams confirmed — what avionics architectures will dominate the new 45,000-ft two-stage category? Registration deadline May 20.