Worked examples · computed by the engine on the server, no AI
Two questions, answered step by step, with NASA's sources
This page runs two complete questions through PYRION — the Moon Base, then ISS cabin air — and prints every step, so it can be checked without clicking anything. Both are live on the dashboard (Moon Base and ISS cabin air presets; set the fuel phase to solid).
Example A · the Moon Base
NASA's Moon Base at 30 % oxygen and 10.2 psi: what has NASA tested near it?
- The condition. The challenge expects the Moon Base at “30% or greater, with a corresponding pressure of 10.2 psi or less”; PYRION checks the corner (30 %, 10.2 psi) at lunar gravity (0.16 g), for solid cabin materials.
- In lunar gravity: nothing in PSI. No PSI test was run in partial gravity; the investigations state only microgravity and normal gravity. NASA's challenge says the same: “there is currently no partial-gravity combustion data available in PSI.”
- The nearest evidence, in other gravities. With gravity left open, the closest solid-fuel tests to this oxygen and pressure are: PSI-26 BASS (microgravity: Oxygen: your 30 % is above the tested 21.5 % to 22.7 % (7.3 points higher)); PSI-25 BASS-II (normal gravity: Oxygen: your 30 % is above the tested 21 % (9 points higher)). Microgravity and normal-gravity results could bound what happens in between (challenge statement); they do not replace a lunar test.
- Why that matters for materials. NASA selects cabin materials with a ground (1 g) test. NASA researchers write: “Recent research has shown that current normal gravity materials flammability results are not conservative when compared to flammability in ventilated microgravity” (Olson & Ferkul, NTRS 20150008961, p. 1). So reduced-gravity evidence is what checks the ground test, and for the Moon there is none in PSI yet.
- What comes next. NASA's planned FM2 experiment would burn one fabric at 37 %, 33 %, 29 %, 25 % oxygen, nominally at 8.2 psia — below the challenge's 10.2 psi upper bound (planned, not in PSI). See which parts of the Moon Base band no planned test reaches.
Fingerprint of the lunar computation (SHA-256): dbe99bf0546d4b69af195863e3e8dcee1d9762e4eee47ddcad34bb60ba876e73
Example B · the ISS cabin, step by step
The same engine on ISS cabin air, with every receipt
1 · The condition
ISS cabin air as NASA describes it: 21 % oxygen at 101.4 kPa (14.7 psia), microgravity. Fuel phase set to solid, because cabin fires start in materials such as fabrics and plastics.
Source: NESC, Impacts of Reduced Pressure Atmospheres on ECLSS (NESC-RP-20-01610).
2 · The verdict for each PSI investigation
0 inside the tested range · 2 outside the tested range · 5 insufficient evidence · 11 not comparable (different gravity, fuel or atmosphere). Ordered by how close their tested conditions are (not by importance).
| # | Investigation | Verdict | Why, in one line |
|---|---|---|---|
| 1 | PSI-25 BASS-II | Just outside the tested data | Oxygen: your 21 % is above the tested 16.4 % to 20.8 % (0.2 points higher). |
| 2 | PSI-26 BASS | Just outside the tested data | Oxygen: your 21 % is below the tested 21.5 % to 22.7 % (0.5 points lower). |
| — | PSI-98 SAFFIRE-I | Insufficient evidence | No usable pressure value for any of the 2 tests. |
| — | PSI-99 SAFFIRE-II | Insufficient evidence | No usable pressure value for any of the 9 tests. |
| — | PSI-100 SAFFIRE-III | Insufficient evidence | No usable pressure value for any of the 2 tests. |
| — | PSI-101 SAME-R | Insufficient evidence | No usable oxygen value for any of the 108 tests. |
| — | PSI-102 SAME | Insufficient evidence | No usable oxygen value for any of the 7 tests. |
| — | PSI-10 ACME/Flame Design | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-20 ACME BRE | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-21 ACME CLD Flame | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-22 ACME E-FIELD Flames | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-23 ACME s-Flame | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-39 CFI | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is liquid fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-68 FLEX-2 | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is liquid fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-69 FLEX | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is liquid fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-106 SLICE | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-107 SPICE | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
| — | PSI-159 ACME CFI-G | Not comparable: different gravity, fuel or atmosphere | Fuel phase: you set solid fuel, the evidence is gaseous fuel. Not comparable: a different gravity, fuel or atmosphere changes how fire behaves, so no distance is defined across it. |
3 · The receipt for the closest one: PSI-25 BASS-II
Verdict: Outside the tested range. Just outside the tested data. Distance: normalized Euclidean distance to the nearest measured point (test T25).
| Test | Value | Where in the NASA file | Text in the file |
|---|---|---|---|
| T25 | o2 mole fraction: 20.8 % by vol | PSI-25_Experimental table_BASS-II.csv · row=124;column=Calibrated initial O2 % by vol | “Calibrated initial O2 % by vol” |
| T26 | o2 mole fraction: 20.8 % by vol | PSI-25_Experimental table_BASS-II.csv · row=125;column=Calibrated initial O2 % by vol | “Calibrated initial O2 % by vol” |
| T1 | pressure: 1 atm | PSI-25_Reports_BASS-II Summary Report.pdf · page=102 | “The tests were conducted in ambient O2 molar fraction of 16 to 21 percent. Ambient pressure was 1 atm.” |
| T2 | pressure: 1 atm | PSI-25_Reports_BASS-II Summary Report.pdf · page=102 | “The tests were conducted in ambient O2 molar fraction of 16 to 21 percent. Ambient pressure was 1 atm.” |
Investigation DOI: 10.60555/4qc4-de67 · PSI record: PSI-25
4 · What NASA set out to learn there, in its own words
“BASS-II results contribute to the combustion computational models used in the design of fire detection and suppression systems in microgravity and on Earth.” (PSI record PSI-25, field “objective”)
“To summarize, BASS-II's approach, microgravity combustion tests were performed aboard the International Space Station.” (PSI record PSI-25, field “approach”)
What if · a PYRION assumption, not evidence
If the Saffire flights were at 1 atm, how would they compare?
The Saffire experiments burned large samples aboard Cygnus spacecraft, and their oxygen is recorded, but no NASA source we downloaded states the cabin pressure. Here, and only here, PYRION assumes 1 atm (101.3 kPa) for the 13 Saffire tests that have oxygen and no pressure, and runs the same engine again. Nothing on the rest of the site uses this assumption, and it never counts as evidence. A NASA statement of the cabin pressure would replace it.
| Investigation | With NASA's records only | If the cabin was at 1 atm (assumption) | Why, in one line (assumption case) |
|---|---|---|---|
| PSI-98 SAFFIRE-I | Insufficient evidence | Just outside the tested data | Oxygen: your 21 % is below the tested 21.5 % to 21.7 % (0.5 points lower). |
| PSI-99 SAFFIRE-II | Insufficient evidence | Just outside the tested data | Oxygen: your 21 % is below the tested 21.5 % to 22.1 % (0.5 points lower). |
| PSI-100 SAFFIRE-III | Insufficient evidence | Inside the tested range | Oxygen: your 21 % is inside the tested 21 % to 21.2 %. |
Why it matters: if a NASA document confirms the pressure, these large-scale cabin-material tests would join BASS and BASS-II as the closest evidence for ISS cabin air. Finding that statement, or measuring it in a future flight, is a concrete next step.
Evidence gaps that matter · computed, nothing assumed
Which missing number would make the most of NASA's data comparable?
For ISS cabin air (solid materials), PYRION lists every value that is not stated in PSI and blocks a comparison. For each, the engine tries candidate values in memory and reports the range the NASA record would need to state for the investigation to become comparable under PYRION's stated rule. Nothing is assumed and nothing is added to the data.
| Investigation | Not stated in PSI | Tests | Would become comparable if PSI stated | Result then |
|---|---|---|---|---|
| PSI-100 SAFFIRE-III | pressure | 2 | 101 kPa (14.6 psia) to 101.8 kPa (14.8 psia) | Inside the tested range — Oxygen: your 21 % is inside the tested 21 % to 21.2 %. |
| PSI-99 SAFFIRE-II | pressure | 9 | 92.3 kPa (13.4 psia) to 112.5 kPa (16.3 psia) | Just outside the tested data — Oxygen: your 21 % is below the tested 21.5 % to 22.1 % (0.5 points lower). |
| PSI-98 SAFFIRE-I | pressure | 2 | 92.3 kPa (13.4 psia) to 112.5 kPa (16.3 psia) | Just outside the tested data — Oxygen: your 21 % is below the tested 21.5 % to 21.7 % (0.5 points lower). |
| PSI-101 SAME-R | oxygen | 0 | no value would (see why) | — No test of this investigation states pressure either, so one value alone would not place it. |
| PSI-101 SAME-R | pressure | 0 | no value would (see why) | — No test of this investigation states oxygen either, so one value alone would not place it. |
| PSI-102 SAME | oxygen | 0 | no value would (see why) | — No test of this investigation states pressure either, so one value alone would not place it. |
| PSI-102 SAME | pressure | 0 | no value would (see why) | — No test of this investigation states oxygen either, so one value alone would not place it. |
Reading it: 3 of the 7 gaps could make an investigation comparable to ISS cabin air if a NASA document stated the value; the rest would still be blocked by another missing value. Asking PSI for these few numbers is the cheapest way to add evidence. Why it matters: large-scale tests of cabin materials in microgravity are the evidence that checks NASA's ground test (Olson & Ferkul, NTRS 20150008961).
For the Moon, no number in PSI can help: no test was run in lunar gravity. The new tests that would span the Moon Base band under PYRION's convention are 34 % O₂ at 10.2 psia; 26.5 % O₂ at 10.2 psia (Mission Planner).
“Comparable” means inside or just outside the tested range under PYRION's stated rule (0.5 % tolerance); it does not predict how a flame behaves.
5 · The limits, and what to do next
- A verdict compares conditions; it does not predict how a flame behaves and never says a condition is safe.
- The closest evidence is outside the tested range on at least one axis: values would have to be extended beyond NASA's measurements.
- Axes left open are not compared: diluent, flame type.
- For the Moon Base condition the same engine finds no PSI test in lunar gravity; the Mission Planner shows what the planned FM2 tests would and would not reach.
Fingerprint of this computation (SHA-256): d9e43cebe0b907906c45b9e662fedd000f8e29c4434f658512dc138737db1f37 · engine pyrion-applicability-engine 0.2.0. The same records and condition always give the same fingerprint.