What Happens When an Astronaut Gets Sick? Lessons from Crew-11

Abstract

In January 2026, the International Space Station (ISS) program encountered a seminal operational challenge: the premature termination of the SpaceX Crew-11 mission due to an unresolved medical contingency affecting a crew member. This event, marking the first controlled medical evacuation in the station's twenty-five-year history of continuous habitation, represents a critical inflection point in aerospace medicine and orbital logistics. This report provides an exhaustive, multi-disciplinary analysis of the evacuation, synthesizing the operational timeline, the physiological constraints of spaceflight, the historical precedents of the Soviet Salyut program, and the engineering imperatives that dictated a Pacific Ocean recovery. By dissecting the Crew-11 anomaly, this document elucidates the fragility of human health in the hostile environment of low Earth orbit (LEO) and the complex decision-making matrix required to balance mission objectives with astronaut survivability. It further examines the downstream effects on the expeditionary "skeleton crew," the scientific casualties of the aborted mission, and the implications for future deep-space exploration architectures under the Artemis and Mars programs.

1. Introduction: The Fragility of the Orbital Outpost

1.1 The Illusion of Routine

For over a quarter of a century, the International Space Station (ISS) has stood as a testament to human permanence in space. Orbiting the Earth every 90 minutes at an altitude of approximately 400 kilometers (250 miles), the station has evolved from a construction site into a bustling national laboratory.¹ The operational rhythm of the station—punctuated by cargo arrivals, crew rotations, and spacewalks—has achieved a level of reliability that borders on the routine. However, the events of January 2026 served as a stark reminder that spaceflight remains an inherently dangerous endeavor, where the margin between a nominal mission and a medical crisis is vanishingly thin.

The SpaceX Crew-11 mission, comprising NASA astronauts Zena Cardman and Mike Fincke, Japan Aerospace Exploration Agency (JAXA) astronaut Kimiya Yui, and Roscosmos cosmonaut Oleg Platonov, launched in August 2025 with the expectation of a standard six-month tenure.² Their mission profile was typical of the Commercial Crew era: a heavy slate of biological research, maintenance of the aging orbital complex, and public outreach. Yet, in the first week of 2026, a medical anomaly disrupted this cadence, forcing NASA and its international partners to execute a contingency procedure that had existed on paper for decades but had never been tested in the ISS era: a controlled medical evacuation.²

1.2 The Significance of the Evacuation

The decision to bring Crew-11 home early is historically significant for several reasons. First, it broke the 25-year streak of uninterrupted, scheduled mission completions on the ISS. While crews have faced technical emergencies—ammonia leaks, thruster failures, and close encounters with space debris—never before had a medical condition necessitated the early return of an entire crew complement.²

Second, the evacuation highlighted the operational constraints of the "lifeboat" model used on the ISS. Unlike a hospital on Earth, where a single patient can be transported by ambulance while the hospital continues to function, the ISS relies on docked spacecraft that serve as escape pods for their specific crews. The departure of the SpaceX Dragon Endeavour to evacuate one patient necessitated the departure of all four crew members assigned to that vehicle.⁵ This "all-for-one" architecture has profound implications for station staffing and scientific continuity, instantly reducing the station's workforce by more than half.

Third, the event brought into sharp focus the "diagnostic gap" in space medicine. The inability of the station's onboard medical facilities to adequately diagnose or treat the crew member's stable yet serious condition underscores a critical vulnerability as humanity prepares for missions to the Moon and Mars, where an early return will not be an option.⁴

1.3 Scope of Analysis

This report aims to provide a comprehensive reconstruction of the Crew-11 evacuation. It will explore the timeline of the event, the medical decision-making process, and the specific physiological risks associated with reentry for an ill astronaut. It will also delve into the engineering changes to the SpaceX Dragon vehicle that necessitated a shift to Pacific Ocean recovery operations—a logistical detail that added complexity to the evacuation. Finally, it will analyze the historical context of the 1985 Salyut 7 evacuation, the only comparable event in spaceflight history, to draw parallels and distinctions between the Soviet and American approaches to medical contingencies.

2. The January Contingency: Event Reconstruction and Decision Matrix

2.1 The Disruption of Expedition 74

The International Space Station operates on a rigid timeline known as the "daily execute package," which details every 15-minute block of an astronaut's day. In early January 2026, the crew of Expedition 74 was preparing for a period of high-intensity operations. Two major spacewalks (Extravehicular Activities, or EVAs) were on the schedule. NASA astronauts Zena Cardman and Mike Fincke were slated to exit the Quest airlock on Thursday, January 8, to perform critical upgrades to the station's power system, specifically the installation of cabling for new roll-out solar arrays.³

The first public sign of an anomaly appeared on Wednesday, January 7, when NASA abruptly announced the postponement of the January 8 spacewalk. While EVA delays are not uncommon—often triggered by minor spacesuit issues or space debris tracking—the agency's justification was unusual. NASA cited a "medical concern" with one of the crew members.³ This vagueness, necessitated by medical privacy laws, immediately signaled that the issue was not a technical failure of the suit or station hardware, but a physiological issue with a human operator.

2.2 The Evolution of the Crisis

The timeline of the crisis reveals a rapid escalation from a localized schedule change to a mission-ending decision.

• January 7 (Wednesday): A crew member reports a health issue. The flight surgeon at Mission Control Center-Houston (MCC-H) conducts a private medical conference (PMC) with the affected astronaut. Given the upcoming physical exertion of a spacewalk, the EVA is scrubbed as a precaution.²

• January 8 (Thursday): The medical evaluation continues. It becomes apparent that the onboard diagnostic capabilities—limited to ultrasound, basic blood work, and vital signs monitoring—are insufficient to fully characterize the condition or rule out serious progression. NASA Administrator Jared Isaacman and Chief Health and Medical Officer Dr. J.D. Polk hold a press briefing. They announce the decision to terminate the Crew-11 mission early.⁴

• January 9-11 (Friday-Sunday): Mission planners at SpaceX and NASA evaluate orbital mechanics and weather patterns. The primary constraint is the sea state in the Pacific Ocean recovery zones. The decision is made to target an undocking on January 14, providing a five-day buffer to configure the station and allow the crew to prepare.⁴

• January 12 (Monday): The Change of Command ceremony takes place. Mike Fincke, the commander of Expedition 74, hands over the symbolic "key to the station" to Roscosmos cosmonaut Sergey Kud-Sverchkov.⁹ This legal formality is essential; the ISS must always have a designated commander onboard.

• January 14 (Wednesday): The SpaceX Dragon Endeavour autonomously undocks from the Harmony module's forward port at approximately 5:00 PM EST.⁴

• January 15 (Thursday): The capsule executes its deorbit burn and splashes down off the coast of California at 3:40 AM EST.¹⁰

2.3 The "Diagnostic Gap" and the Decision to Return

The central question surrounding the evacuation was why a "stable" astronaut needed to return immediately. Dr. J.D. Polk provided the answer: the "capability to diagnose and treat this properly does not live on the International Space Station".⁴

The ISS is equipped with the Crew Health Care System (CHeCS), which includes the Health Maintenance Facility (HMF). The HMF contains:

• Advanced Life Support: Defibrillators, intubation kits, and ventilators.

• Diagnostics: A portable ultrasound device (used for everything from eye exams to abdominal scans), a blood analyzer, and an ophthalmoscope.¹¹

• Pharmacy: A robust stock of antibiotics, analgesics, anti-emetics, and epinephrine.

However, the HMF lacks "tertiary" diagnostic tools. There is no CT scanner to detect internal hemorrhaging or complex soft tissue pathologies. There is no MRI machine to investigate neurological issues. There is no catheterization lab for cardiac interventions. If a crew member presents with symptoms that could mimic a condition requiring surgery (e.g., abdominal pain that could be appendicitis or just severe gas), the flight surgeons are left with a probability game.

In the case of Crew-11, the medical board likely faced a condition that was stable at the moment but carried a risk of rapid deterioration that the onboard facilities could not manage. The "precautionary principle" dictated that the risk of keeping the astronaut in a resource-limited environment outweighed the operational cost of ending the mission.

2.4 Controlled vs. Emergency Evacuation

NASA was careful to categorize the event as a "controlled medical evacuation" rather than an "emergency evacuation".⁵ This distinction is critical in aerospace operations.

• Emergency Evacuation: This protocol is reserved for immediate threats to life (e.g., cardiac arrest, uncontainable fire, hull breach). It involves an immediate "sprint to the lifeboat," a rapid undocking, and a potentially high-G ballistic reentry to reach a hospital within hours. This places immense physical stress on the crew and carries a higher risk of landing errors.

• Controlled Evacuation: This protocol allows for a planned departure. Flight controllers can wait for optimal weather, ensuring a safe splashdown. The reentry trajectory can be optimized for lower G-loads (lifting reentry). The crew has time to pack science samples and clean the station. The Crew-11 return followed this profile, prioritizing safety and stability over speed.

3. Historical Precedents: The Shadow of Salyut 7

To contextualize the singularity of the Crew-11 event, one must look back forty years to the Cold War era. Until 2026, the ISS had been a sanctuary from medical evacuations. The only comparable event occurred aboard the Soviet Salyut 7 station in 1985, a chapter of space history that offers haunting parallels and distinct contrasts to the modern crisis.

3.1 The Illness of Vladimir Vasyutin

In September 1985, the Soviet Union launched the Soyuz T-14 mission to the Salyut 7 space station. The crew consisted of Commander Vladimir Vasyutin, Flight Engineer Viktor Savinykh, and Researcher Alexander Volkov. The mission had a clandestine military objective: to conduct extensive surveillance experiments using the TKS module docked to the station.¹³

Vasyutin, a 33-year-old cosmonaut on his first flight, was under immense pressure to succeed. Approximately two months into the mission, he began to suffer from a condition initially reported as "inflammation" and a "fever".¹³ Unlike the modern ISS, which allows for private medical conferences, the Soviet system often discouraged the reporting of illness, viewing it as a weakness or a mission failure. Vasyutin initially attempted to conceal his symptoms, but his condition deteriorated rapidly.

By November 1985, Vasyutin was reportedly suffering from a fever of 104°F (40°C), severe pelvic pain, and insomnia.¹⁴ He was effectively incapacitated, unable to perform the complex military experiments or command the station. The diagnosis, later widely believed to be acute prostatitis (a bacterial infection of the prostate) or a severe urinary tract infection, was exacerbated by the microgravity environment.⁷ In zero gravity, fluid shifts can complicate urinary retention, and the lack of effective antibiotics on board meant the infection could not be controlled.

3.2 The 1985 Evacuation

On November 21, 1985, the Soviet mission control made the unprecedented decision to terminate the mission. The crew boarded their Soyuz T-14 spacecraft and returned to Earth after only 65 days, leaving the Salyut 7 station unmanned and cutting short the military program.¹⁴

The return was physically brutal. The Soyuz descent module subjects the crew to significant G-forces, and for a patient with severe abdominal and pelvic inflammation, the deceleration would have been excruciating. Upon landing, Vasyutin was immediately hospitalized.

3.3 The Psychological Controversy

The Vasyutin incident sparked a decades-long debate in space medicine regarding the interplay between physical and psychological health. Some Soviet and later Russian sources hinted that Vasyutin’s "illness" had a psychosomatic component, or that the stress of command contributed to his immune system's collapse.¹⁵ Vasyutin himself later commented on his "frame of mind," and reports surfaced that he had concealed a pre-existing urological condition to ensure his flight assignment.¹⁵ This incident led to rigorous changes in psychological screening and pre-flight quarantine protocols, influencing the standards used by the ISS partners today.

3.4 1985 vs. 2026: A Study in Evolution

Comparing Salyut 7 to Crew-11 reveals the evolution of spaceflight culture:

• Transparency: The Soviet evacuation was shrouded in mystery, with state media releasing vague reports of an "ailment" only after the landing. In contrast, NASA announced the Crew-11 issue immediately, balancing transparency with the specific legal requirements of medical privacy.²

• Medical Culture: The Salyut era culture of "toughing it out" has been replaced by a culture of early reporting. The Crew-11 astronaut reported the issue before it became incapacitating, allowing for a controlled rather than emergency return.

• Technology: Vasyutin returned in a cramped Soyuz. Crew-11 returned in a spacious Dragon, with a reentry profile designed to minimize physiological stress.

4. The Physiological Challenge: Reentry with Medical Complications

Returning to Earth is the most physically demanding phase of any spaceflight. For a healthy astronaut, it is an endurance test. For an ill astronaut, it is a medical gauntlet that requires precise management of physics and physiology.

4.1 The Deconditioned Body

After five months in orbit, the bodies of the Crew-11 astronauts have undergone profound adaptations to weightlessness.

• Cardiovascular Atrophy: Without gravity to pull blood into the legs, the heart works less hard. Blood volume decreases by 10-20% as the body sheds "excess" fluid.¹⁹

• Neurovestibular Dysfunction: The inner ear has acclimated to the lack of "down." Reintroducing gravity causes extreme vertigo and motion sickness in nearly all returning astronauts.

• Bone and Muscle Loss: despite daily exercise, some loss of bone density and muscle mass is inevitable, making the skeleton more fragile.²⁰

4.2 The Physics of Deceleration

The SpaceX Dragon capsule enters the atmosphere at 17,500 mph (28,000 km/h). To stop, it must convert that kinetic energy into heat and drag. This deceleration generates G-forces (gravity equivalents).

• Nominal Profile: A controlled lifting reentry generates approximately 3.5 to 4.5 Gs.²¹ This means a 150-pound astronaut feels like they weigh 600 pounds.

• Transverse Loading (+Gx): The seats in the Dragon are oriented so that the G-force pushes the astronaut back into the seat (eyes-in). This is the safest direction for G-tolerance, but it significantly compresses the chest.

• The Respiratory Challenge: Under 4 Gs, the chest wall becomes heavy. The work required to inhale increases dramatically. For a patient with a respiratory infection (like Vasyutin’s rumored pneumonia complications) or abdominal pain, this compression can cause hypoxia (low oxygen) or excruciating pain.²²

4.3 Hydrostatic Shock and Orthostatic Intolerance

The most critical medical moment occurs after splashdown. As the capsule bobs in the ocean, gravity returns. The blood that had been evenly distributed in the body suddenly pools in the legs. In a deconditioned astronaut, the heart cannot pump hard enough to get blood to the brain, leading to "orthostatic intolerance"—fainting upon standing.19

For an ill patient, this risk is compounded. If the medical condition involves dehydration, blood loss, or cardiac instability, the return to 1G could precipitate shock. To mitigate this, the SpaceX recovery team on the MV Shannon is trained to extract the crew horizontally. The astronauts are lifted out of the capsule on seats or stretchers to prevent blood from draining from the brain.23

5. The Logistics of Recovery: The Shift to the Pacific

The Crew-11 evacuation was complicated by a major logistical change in the Commercial Crew Program: the relocation of recovery operations from the Atlantic Ocean (Florida) to the Pacific Ocean (California). This shift, fully implemented in 2025, was driven by a specific engineering anomaly related to the Dragon spacecraft's "trunk."

5.1 The Trunk Debris Anomaly

The SpaceX Dragon consists of the pressurized capsule and an unpressurized service module called the "trunk," which carries solar panels and heat radiators.

In the original mission profile (used for Crew-1 through Crew-8), the trunk was jettisoned before the deorbit burn. This left the trunk in a decaying orbit to reenter the atmosphere naturally weeks or months later. NASA and SpaceX models predicted the trunk would burn up entirely.

However, reality contradicted the models. In 2022 and 2024, large pieces of trunk debris—specifically the carbon-composite structure and metal mounting points—survived reentry and impacted land in Australia and Canada.24 While no one was injured, the risk of a casualty was deemed unacceptable.

5.2 The "Trunk-Attached" Deorbit Solution

To ensure public safety, SpaceX engineered a new reentry procedure. The Dragon now performs its deorbit burn with the trunk still attached. This allows the trunk to be driven into the atmosphere on a precise trajectory, ensuring any surviving debris falls into a designated "spacecraft cemetery" in the open ocean.25

However, the orbital mechanics of this maneuver dictate the landing site. To drop the trunk safely in the unpopulated Pacific while landing the capsule near recovery forces, the entire landing zone had to shift to the West Coast.25

5.3 The Pacific Recovery Architecture

By January 2026, SpaceX had established a new recovery hub at the Port of Long Beach, California.24 The primary recovery vessel, MV Shannon, was repositioned from Florida to the Pacific.26

This shift added a variable to the Crew-11 evacuation: the Pacific winter. The Pacific Ocean generally has higher sea states (larger waves) than the Gulf of Mexico. A medical evacuation requires calm seas to ensure the transfer of the patient from the capsule to the ship is not jarring. The delay in the Crew-11 return from January 8 to January 15 was largely driven by the need to wait for a "weather window" where the Pacific swells were low enough to permit a safe medical extraction.4

The recovery vessel MV Shannon is a floating medical center. It features:

• A Helipad: For rapid evacuation of the patient to a shore-based hospital if urgent.

• Medical Bay: Equipped with advanced monitoring, fluids, and stabilization gear that exceeds what is available on the ISS.²³

• Fast Boats: To reach the capsule within minutes of splashdown and assess the condition of the vents (to ensure no toxic hypergolic fumes are present) before the main ship arrives.²⁷

6. The Human Element: Crew-11 and Expedition 74

The evacuation did not just involve hardware; it disrupted the lives of a tightly knit team of professionals.

6.1 The Crew-11 Complement

The Crew-11 astronauts were a veteran mix of international flyers:

• Zena Cardman (Commander, NASA): A marine scientist and first-time flyer who had distinguished herself as a leader during the expedition.³

• Mike Fincke (Pilot, NASA): A legendary figure in spaceflight, Fincke was completing his fourth mission. He was serving as the Commander of the ISS (Expedition 74) at the time of the incident.³

• Kimiya Yui (Mission Specialist, JAXA): A Japanese astronaut and former pilot, serving his second tour on the station.³

• Oleg Platonov (Mission Specialist, Roscosmos): A Russian cosmonaut on his rookie flight.³

The psychological impact of the evacuation on this crew cannot be overstated. Astronauts train for years for a six-month mission. To have it curtailed by a medical issue involves a sense of unfinished business and concern for the affected colleague. The "Change of Command" ceremony on January 12 was likely a somber affair, with Fincke handing over the station to the Russian segment earlier than planned.⁹

6.2 The "Skeleton Crew" of Expedition 74

The departure of Crew-11 leaves the ISS in a precarious staffing position, known as a "skeleton crew."

• The Stay-Behinds: Only three people remain on the massive station: Roscosmos cosmonauts Sergey Kud-Sverchkov (the new Commander) and Sergei Mikayev, and lone NASA astronaut Chris Williams.²

• Operational Risk: The ISS is designed for a crew of seven. With only three, the "overhead" of running the station (fixing toilets, changing filters, monitoring life support) consumes a huge percentage of their time.

• The Lone American: Chris Williams is now the sole operator of the USOS (US Orbital Segment), which includes the American, European, and Japanese labs. He must manage the science and systems of three modules alone. This situation places immense pressure on him and effectively halts most new research until the arrival of Crew-12, potentially accelerated to February to relieve the strain.³

7. Scientific Causalities: The Cost of Early Return

The ISS is a laboratory, and the early return of Crew-11 resulted in significant scientific casualties. The crew was in the midst of several long-duration experiments that relied on specific timelines.

7.1 Regenerative Medicine: The Stem Cell Loss

A flagship experiment for Crew-11 was StemCellEx-IP1, sponsored by BioServe Space Technologies. This study aimed to generate large quantities of induced pluripotent stem cells (iPSCs) in microgravity. The hypothesis is that the lack of sedimentation and shear forces in space allows stem cells to grow into 3D structures more naturally than in 2D petri dishes on Earth.30

The experiment required a precise growth cycle. The early return likely forced the crew to "fix" (chemically preserve) the samples prematurely or return them live before they had reached the desired maturity. This could compromise the data regarding the "mass production" capabilities of space-based stem cell facilities.30

7.2 Plant Biology and Nutrient On-Demand

Another critical study involved the growth of plant cells to produce nutrients on demand—a technology vital for Mars missions where vitamins in pre-packaged food degrade over time. The ExoLab 11 and related plant division studies required continuous monitoring.³² The sudden departure meant these experiments had to be terminated or put into a dormant state, potentially invalidating the "growth rate" data that was the study's primary output.

The "Loss of Science" metric is tracked carefully by the ISS program. The evacuation likely resulted in the loss of hundreds of crew hours of scheduled research, a setback for the commercial and academic partners who paid for the slot.

8. Future Horizons: Implications for Deep Space

The Crew-11 evacuation serves as a "stress test" for the future of human space exploration. The lessons learned here will directly influence the medical architectures of the Artemis program (returning to the Moon) and the first human missions to Mars.

8.1 The Tyranny of Distance

The ISS is 250 miles away. The evacuation took one week from diagnosis to splashdown, but in a true emergency, the crew could be on the ground in 4 hours.

On a mission to Mars, the transit time is 6 to 9 months. There is no abort option. If a Crew-11-style medical event occurred halfway to Mars, there would be no "controlled evacuation." The crew would have to treat the condition with whatever resources were on board.

This reality forces a paradigm shift from "stabilize and evacuate" (the ISS model) to "diagnose and treat" (the Mars model). The inability of the ISS to diagnose the Crew-11 patient proves that current space medical systems are insufficient for Mars. Future ships must carry:

• Autonomous Diagnostic AI: Systems capable of interpreting ultrasound or other data without ground support (due to communication delays).

• Advanced Imaging: Lightweight MRI or CT scanners to see inside the body.

• Surgical Capability: The ability to perform an appendectomy or treat internal bleeding in microgravity.

8.2 Privacy in the Age of Commercial Space

The Crew-11 event also highlighted the tension between transparency and privacy. NASA successfully protected the astronaut's identity, citing HIPAA regulations. However, as the space station becomes more commercialized, with private citizens flying, the expectations of privacy may clash with the public's desire to know. The seamless handling of the Crew-11 narrative suggests that NASA has developed a robust playbook for managing medical PR, a skill that will be essential as the population in orbit grows and diversifies.

9. Conclusion

The controlled medical evacuation of Crew-11 in January 2026 stands as a watershed moment in spaceflight history. It demonstrated the resilience of the ISS partnership, the flexibility of the Commercial Crew Program, and the maturity of space medical protocols. The successful coordination of a Pacific recovery, the management of a skeleton crew, and the safe return of the patient validated the contingency planning that has been in place for decades.

However, the event also stripped away the veneer of invincibility that had settled over the ISS program. It revealed the limitations of orbital diagnostics and the stark cost of medical crises in terms of lost science and operational disruption. As humanity looks toward the Moon and Mars, the "Orbital Triage" of Crew-11 will serve as a critical case study. It reminds us that while our rockets have become reusable and our stations more comfortable, the human body remains the most fragile and unpredictable system in the loop. The next great leap in space exploration will depend not just on better propulsion, but on better medicine.

10. Statistical and Technical Addendum

Table 1: Crew-11 Mission Data Profile

Parameter	Detail
Spacecraft	SpaceX Crew Dragon Endeavour (C206)
Launch Date	August 1, 2025
Undocking Date	January 14, 2026 (17:00 EST)
Splashdown Date	January 15, 2026 (03:40 EST)
Mission Duration	~167 Days (Shortened from ~190)
Recovery Zone	Pacific Ocean (Southern California Coast)
Recovery Vessel	MV Shannon
Reason for Return	Undisclosed Medical Contingency (Stable)

Table 2: Comparative Analysis of Space Station Evacuations

Feature	Salyut 7 (1985)	ISS Crew-11 (2026)
Affected Crew	Vladimir Vasyutin (Commander)	Undisclosed Crew Member
Diagnosis	Acute Prostatitis / Inflammation	Undisclosed (Requires Ground Diagnostics)
Operational Impact	Station Abandoned	Skeleton Crew (3) Remains
Evacuation Type	Emergency / Precipitous	Controlled / Planned
Return Vehicle	Soyuz T-14 (Ballistic/High-G risk)	Crew Dragon (Lifting Entry/Low-G)
Transparency	State Secrecy	Public Announcement / Privacy Protected

Table 3: ISS Medical Facility vs. Ground Capabilities

Capability	ISS HMF (Onboard)	Level I Trauma Center (Ground)
Imaging	Portable Ultrasound, Ophthalmoscope	CT, MRI, X-Ray, Fluoroscopy
Pathology	Basic Blood/Urine Analysis	Full Histopathology, Culture & Sensitivity
Surgery	Minor suturing, abscess drainage	Full operative capability (Laparoscopic/Open)
Pharmacy	Limited formulary (shelf-life constrained)	Full pharmacopeia
Staffing	CMO (Astronaut with paramedic training)	Board-certified Specialists

Table 4: SpaceX Dragon Reentry G-Force Profile

Phase	Nominal G-Load	Duration	Physiological Risk for Ill Patient
Deorbit Burn	< 0.5 G	12-15 mins	Minimal.
Atmospheric Entry	0.5 - 3.5 G	~5 mins	Onset of chest compression.
Peak Deceleration	3.5 - 4.5 G	2-3 mins	High Risk. Difficulty breathing, pain exacerbation, potential arrhythmia.
Drogue Deploy	1.5 - 2.0 G (Jolt)	Instant	Mechanical shock/vibration.
Main Chutes	1.0 - 1.5 G	~4 mins	Pendulum swinging (motion sickness).
Splashdown	2.0 - 3.0 G	Instant	Impact trauma, risk of orthostatic collapse.

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