PRD-012 — Spaceflight Fleet
Orrery · Product Requirements · v0.1 · May 2026
Status: Accepted (v0.6 ship — /fleet; RFC-016 closed via ADR-052 / ADR-053 / ADR-054) Sources: PRD-009 (Mission Catalog) for the card-grid template; PRD-010 / PRD-011 (ISS / Tiangong Explorers) for detail-panel + provenance reuse; existing rockets.json + missions.json + iss-* / tiangong-* datasets as primary data sources to cross-reference. Audiences: curious learner, STEM student, space enthusiast (PA §audiences) Promises: real mission data fully attributed, educational at every level (PA §promises) Principles: physics first, attribution is design (PA §principles) Why this is a PRD: Orrery already tells the story of what was done (Mission Catalog) and what was built in a few specific places (ISS / Tiangong Explorers). It does not yet tell the story of the machines themselves — the rockets that put crews in orbit, the rovers driving on Mars, the observatories mapping the universe, the retired stations whose legacy enabled today's flights. A Saturn V card next to a Falcon 9 card next to a Space Shuttle card — a direct ladder from Vostok 1 to Crew Dragon, from Lunokhod-1 to Perseverance — gives users a hardware-first path through 70 years of spaceflight that complements the mission-first path. Every entry has a builder, a maiden flight, and a list of the missions it enabled.
A student arrives at /fleet. The grid loads: ~110 cards across categories — launchers, crewed spacecraft, cargo spacecraft, stations, rovers, landers, orbiters, observatories. They filter to crewed spacecraft and see Vostok, Voskhod, Mercury, Gemini, Apollo CSM, Soyuz 7K-OK, Soyuz T, Soyuz TM, Soyuz TMA, Soyuz MS, Buran, Space Shuttle Orbiter, Shenzhou, Crew Dragon, Starliner, New Shepard, Orion, Gaganyaan — a single row that compresses six decades of human spaceflight engineering, with each Soyuz generation distinguishable. They filter to STATUS=FAILED and see Mars 2, Schiaparelli, Beresheet, Hakuto-R, Vikram CY-2, N1, Hitomi — the redemption-arc layer of the story, paired with their successors. They click Vostok 1. The panel opens: the spacecraft schematic (ANATOMY tab reusing the spacecraft-anatomy work), notable-flight patches, Yuri Gagarin's portrait, a link to Vostok 1's full mission entry under /missions, and three tiers of links (intro / core / deep). They click Saturn V next. Same panel shape: anatomy, specs, the 13 Apollo mission cards it launched, builder + agency + retirement. The hardware lineage becomes legible.
§why
The Mission Catalog answers "what missions have been flown?" The ISS / Tiangong Explorers answer "how is this station put together?" Neither answers the broader question: "what hardware exists, and how is it related to what came before it?"
A Vostok-to-Crew-Dragon thread is a story Orrery can tell uniquely well, because:
- We already have the primitives.
rockets.json(13 launchers),missions.json(37 missions, each with alaunch_vehiclefield),iss-modules+iss-visitors+tiangong-*(~30 station components),earth-objects(orbital satellites including observatories),moon-sites(lunar rovers + landers). A new aggregatefleet.jsonbecomes the connective tissue: one canonical entry per piece of hardware, with cross-references to the existing data. - The detail panel already exists. ANATOMY tab from the visiting-spacecraft schematics work in May 2026 generalises directly: rockets, rovers, observatories all want a labelled-subsystem schematic.
- The card grid pattern is solved.
/missions(PRD-009) is the proven template — filter chips, lazy-loaded cards, deep-link?id=.... Reuse the structure.
The shape of the page promises: every machine that ever flew has a story, and Orrery shows you which other Orrery pages know more about it.
Why now
The visiting-spacecraft anatomy diagrams shipped in May 2026 (Crew Dragon, Soyuz, Cygnus, Starliner, HTV-X, Progress, Cargo Dragon, Shenzhou, Tianzhou) created the visual + interaction template. A fleet page is the logical next step — taking that schematic treatment from "9 station visitors" to "every crewed spacecraft + every launcher + every rover + every observatory ever flown."
§audiences
Same primary audiences as PRD-009 / PRD-010 / PRD-011:
- Curious learner — wants to see Saturn V and Falcon 9 side by side, click into either, and follow the lineage. Scrollable filterable grid is the right primitive.
- STEM student — wants the specs (height, mass, thrust, payload-to-LEO, manufacturer, first/last flight). Detail panel's OVERVIEW tab grid covers this.
- Space enthusiast — wants the cross-references. Every Saturn V card reveals "missions launched: Apollo 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, Skylab" with each item linking to the mission detail. Every Crew Dragon card reveals "first flight: Demo-2, then Crew-1, Crew-2..." Closes the loop with the Mission Catalog.
§promises
- Every entry attributed. Builder + agency + country + first flight (and retirement, if applicable). Imagery sourced via the existing pipeline (ADR-046 / ADR-047) with three priority tiers:
airandspacehistory.com— Marko's own museum-photography collection from Russia, USA, UK, France, Germany, Netherlands museums (Smithsonian / Cosmonautics Museum / Science Museum London / Le Bourget / Speyer / Aviodrome / etc). Photos are first-party originals of actual hardware, often with composition unavailable elsewhere. Each photo's gallery row carriescredit: "© airandspacehistory.com"+ a deep link back to the photo's page on airandspacehistory.com. Acts as both unique value-add (museum-grade hardware photography, not stock press kits) and natural cross-promotion.- Agency-first (per ADR-046) — NASA Image Library / ESA Photo Library / JAXA Library / Roscosmos / CMSA archives.
- Wikimedia Commons fallback — for entries without first-party or agency coverage.
- Every entry cross-linked. When a piece of hardware is referenced elsewhere in the app — a launcher referenced in a mission's
launch_vehicle, an ISS module attached to a station — the Fleet card surfaces those references. Bidirectional: the linked mission's panel can hint "see also: Saturn V" in a future iteration. - Mission badges and crew portraits where applicable. Crewed-spacecraft entries include the mission patches of every flight (Apollo 11 patch, STS-1, Demo-2, etc.) and crew portraits sourced from agency archives. Adds a human dimension to the hardware story. (Per Marko's V1 decision: in scope, not deferred.)
§principles
- Physics first. Spec grid in OVERVIEW is the truth: real heights, masses, thrusts, payloads. Round numbers only when official specs themselves are rounded.
- Attribution is design. Builder line + country + agency badge is the first thing the user sees on every card, not a footer afterthought.
- Mobile-first. Same
/missionsmobile-first card grid translates directly. Detail panel uses the existing mobile bottom-sheet / desktop right-drawer pattern.
§scope
V1 — per-generation curated set (~110 entries)
Per Marko's locked decisions:
- One entry per generation/variant (not per family) — Soyuz 7K-OK / T / TM / TMA / MS each get their own entry; Long March 2F / 5 / 5B / 7 each separate.
- ~110 entries, expanded from initial ~50 estimate to honour the per-generation rule and "every machine, every outcome" framing.
- Failure / partial-success entries included — N1, Buran, Schiaparelli, Beresheet, Hakuto-R, Vikram CY-2, Mars 2, Hitomi, etc. Failure drives the next generation; the page reads as the full story, not just the wins.
Categories and target counts
| Category | V1 count | Examples |
|---|---|---|
| launcher | ~22 | Atlas LV-3B, Titan II, R-7/Vostok, Saturn IB, Saturn V, N1, Soyuz-U, Space Shuttle stack, Proton-M, Ariane 5, Soyuz-FG, Atlas V, Long March 2F, H-IIA, Falcon 9 Block 5, Energia, Long March 5/5B, Falcon Heavy, LVM3, SLS Block 1, Long March 7, H3, Ariane 6 |
| crewed-spacecraft | ~18 | Vostok, Voskhod, Mercury, Gemini, Soyuz 7K-OK, Apollo CSM Block II, Apollo LM, Soyuz T, Space Shuttle Orbiter, Buran, Soyuz TM, Soyuz TMA, Shenzhou, Soyuz MS, Crew Dragon, Starliner, New Shepard, Orion, Gaganyaan (planned) |
| cargo-spacecraft | ~11 | Progress 7K-TG, Progress M, Cargo Dragon v1, HTV, Cygnus Standard, ATV, Progress MS, Cygnus Enhanced, Cargo Dragon 2, HTV-X, Tianzhou |
| station | ~9 | Salyut 1, Skylab, Salyut 6, Salyut 7, Mir, ISS, Tiangong-1, Tiangong-2, Tiangong |
| rover | ~12 | Lunokhod-1, LRV (Apollo), Lunokhod-2, Sojourner, Spirit, Opportunity, Curiosity, Yutu, Perseverance, Yutu-2, Zhurong, Pragyan |
| lander | ~19 | Luna 9, Surveyor 3, Venera 7-class, Mars 2, Mars 3, Viking 1, Luna 16-class sample return, Mars Polar Lander, Phoenix, Chang'e-3, Chang'e-4, Schiaparelli, InSight, Beresheet, Chang'e-5, Vikram CY-2, Hakuto-R program, SLIM, Vikram CY-3, IM-1 Odysseus |
| orbiter | ~14 | Mariner 4, Mariner 9, Pioneer 10, Voyager 1, Voyager 2, Galileo, Magellan, Phobos 2, Cassini, Mars Express, MRO, Rosetta, Hayabusa2, Juno, Mangalyaan, Chang'e-2, DART, OSIRIS-REx |
| observatory | ~11 | Hubble, Compton GRO, XMM-Newton, Chandra, Spitzer, Kepler, Gaia, Hitomi, TESS, Spektr-RG, JWST, Euclid |
(Bold = added in the per-generation + failure-inclusion expansion vs. the original ~50.)
Country distribution
| Country / agency | Count |
|---|---|
| USA (NASA + commercial) | ~47 |
| USSR / Russia | ~27 |
| China (CNSA / CMSA) | ~12 |
| ESA (multi-country European) | ~10 |
| Japan (JAXA + ispace) | ~7 |
| India (ISRO) | ~6 |
| Israel | 1 |
| International (ISS) | 1 |
(Sum > category total because Hubble + JWST + BepiColombo are jointly attributed US+ESA.)
= ~110 entries. Dataset is curated, not exhaustive — the long tail stays out. V2 expansion is intentional.
Out of scope (V1)
- The full long tail of every variant (each Mariner numbered separately, every Surveyor 1–7 split, every Long March sub-variant). Per-generation rule already adds significant breadth; below-the-line entries defer to V2.
- Orrery-side mission badge / crew photo gallery for non-crewed missions (no badges on rovers).
- Working-satellite long tail — GPS, GLONASS, Starlink, communication satellites stay in
earth-objects.jsononly; they don't get fleet entries unless they're observatories or otherwise iconic (Hubble / JWST / Chandra do, since they have hardware-story value beyond "is in LEO"). - Pure vaporware (no public spec sheets, no announced launch window). PLANNED status entries like Gaganyaan and SLS Block 2 require a published agency reference + named launch window.
- Full SVG coverage for V1 — V1 ships ~30–40 SVGs (the marquee tier per Phase F.2). V1.5 fills the next 30; V2 reaches full ~110 coverage. ANATOMY tab no-ops gracefully on entries without an SVG yet.
§what-it-must-do
Page surface
- Top-level nav slot:
EXPLORE → MISSIONS → PLAN → FLY → EARTH → MOON → MARS → ISS → TIANGONG → FLEET → SCIENCE. Inserted betweenTIANGONGandSCIENCEso the inventory-style screens (ISS / Tiangong / Fleet) cluster together with SCIENCE as the educational tail. /fleetroute loads a card grid (mirror of/missions).- Filter chips:
CATEGORY(the 8 above),AGENCY(NASA / Roscosmos / ESA / JAXA / CNSA / ISRO / SpaceX / Northrop Grumman / Boeing / Blue Origin / ispace / multi),EPOCH(named historic epochs — see §epochs below; replaces the date-range ERA chip with story-shaped buckets),STATUS(FLOWN / ACTIVE / RETIRED / FAILED / PLANNED). - Epoch timeline strip above the card grid: a horizontal scrub bar from 1957 → present + planned, labelled with the 8 named epochs. Click an epoch band to filter; hover/tap reveals the entry count for that epoch. Today indicator (vertical line) marks "now". Mobile collapses to a compact horizontal swipe carousel.
- Sort options: chronological descending (default — newest first by first flight, surfaces current/active hardware at the top), chronological ascending (oldest first), alphabetical, by category.
- Deep-link
?id=saturn-vopens the detail panel pre-selected. ?view=listlow-fidelity fallback like/issand/tiangong.
Card design
Mirrors /missions cards but tuned for hardware:
- Hero photo (full-bleed top, 16:9 or 4:3)
- Name (display font, large)
- Category chip + agency badge
- Era chip (1960s, 1970s, etc.)
- First flight year + status
- One-line "first of" / "best known for" tagline (e.g., "First crewed orbital flight" for Vostok)
- Click → opens detail panel
§epochs — named historic spans for filtering + timeline UX
Replaces the original 5-bucket date-range ERA chip with 8 named epochs that map to actual milestones rather than arbitrary decade-ish chunks. Each epoch is both a chip filter and a band on the timeline strip. Ranges intentionally overlap where two strands ran concurrently (Shuttle program straddles First-Stations and ISS-Assembly epochs).
| Epoch | Years | Theme | ~Entries |
|---|---|---|---|
| First Steps | 1957–1961 | Sputnik, first satellites, R-7, first crewed orbital | ~6 |
| Space Race | 1961–1969 | Mercury, Vostok, Voskhod, Gemini, Apollo prep, lunar build-up, Mariner 4 | ~12 |
| Lunar Era | 1969–1972 | Apollo lunar landings, Lunokhod, Soviet N1 failures, LRV | ~8 |
| First Stations | 1973–1986 | Skylab, Salyut 1–7, Apollo-Soyuz, Voyager grand tour, Vikings | ~16 |
| Shuttle & Mir | 1981–1998 | Shuttle program, Mir, Buran/Energia, Galileo, Magellan, Hubble | ~22 |
| ISS Assembly | 1998–2011 | ISS construction, Shuttle retirement, Mars Spirit/Opportunity, Cassini | ~14 |
| Commercial Era | 2011–present | Crew Dragon, Falcon, Tiangong, JWST, Perseverance, Hayabusa2, commercial lunar | ~30 |
| Lunar Return | 2024+ | Artemis, Starship, Gaganyaan, IM-class, planned lunar missions | ~6 |
EPOCH chip values are these 8 names. Timeline strip UI renders horizontal bands keyed to these names, with the entry count visible per band on hover/tap. The strip has a fixed-width axis (1957 → 2030+) and clicking a band selects + filters that epoch's hardware. Today-indicator shows where we are relative to the spans.
Cross-route linking — fleet ↔ everything
Locked decision: the fleet page becomes the canonical hardware reference for the rest of the app. Mission entries, surface-map markers, and orbital-object panels all link into fleet entries; fleet entries link back to the contexts they appear in.
Schema additions
| File | New field | Purpose | Example |
|---|---|---|---|
static/data/missions/{dest}/{id}.json | fleet_refs: [{ id, role }] | Map mission → its launcher + spacecraft + payload fleet entries | [{id: "saturn-v", role: "launcher"}, {id: "apollo-csm-block-ii", role: "spacecraft"}, {id: "apollo-lm", role: "spacecraft"}] |
static/data/moon-sites.json | fleet_refs: [...] | Lunar landing site → hardware that landed there | Apollo 11 site → [{id: "apollo-csm-block-ii"}, {id: "apollo-lm"}, {id: "lrv-apollo"}] (LRV only on later Apollos) |
static/data/mars-sites.json | fleet_refs: [...] | Mars landing site → rover/lander | MSL site → [{id: "curiosity"}] |
static/data/earth-objects.json | fleet_refs: [...] | LEO satellite/observatory → fleet entry | Hubble → [{id: "hubble"}] |
static/data/fleet/{cat}/{id}.json | linked_sites: [...] | Reverse pointer to surface markers / orbits | Curiosity → [{type: "mars", site_id: "msl"}] |
Detail panel rendering
/missionspanel (existing) gains a "Hardware" row in OVERVIEW that listsfleet_refsas clickable chips:[Saturn V →] [Apollo CSM Block II →] [Apollo LM →]./moonand/marssite panels gain a "Hardware" section listingfleet_refschips./earthobject panel gains "See in Fleet: [Hubble →]" CTA./fleetentry panel OVERVIEW tab renderslinked_sitesreverse pointers: e.g., Curiosity entry shows "Operating site: [Gale Crater on /mars →]".- MISSIONS tab on fleet panel already covered: cross-links to /missions are already locked.
Build-time validation
scripts/validate-data.ts extended to assert symmetric integrity:
- Every
fleet_refs[*].idresolves to a real entry infleet/index.json. - Every fleet entry's
linked_sites[*]resolves to a real moon-site / mars-site / earth-object. - Bidirectional check: if a mission has
fleet_refs: [{id: "saturn-v", role: "launcher"}], then Saturn V'slinked_missionsarray MUST include that mission (catches drift). - Build fails closed if any fleet_id reference dangles.
This makes fleet the single source of truth for hardware metadata, and every other route becomes a per-context view that pivots to fleet for the canonical record. Reads as one cohesive product rather than parallel datasets that happen to mention the same machines.
Detail panel tabs
Built as new component FleetEntryPanel.svelte (copied from StationModulePanel.svelte per RFC-016 OQ-4 lock — keeps station-specific concerns out, generalises to a unified EntityDetailPanel.svelte in v0.7+):
- OVERVIEW — specs grid (height / mass / thrust / payload / first flight / last flight / manufacturer / status), editorial paragraph, "best known for" highlight. For station entries with explorer routes (ISS, Tiangong), prominent "Open ISS Explorer →" CTA at the top of the OVERVIEW tab deep-links to
/issor/tiangong. - GALLERY — same per-entry gallery infrastructure as
/missionsand/iss. Targets ≥4 photos per entry. - ANATOMY — labelled-subsystem schematic in the canonical /science chapter style (white-on-dark, monospace labels, viewBox 400×320, teal accent leader lines). Hand-authored per fleet entry — every one of the ~110 entries gets its own SVG, contributed as original artwork in the same Orrery house style as the 9 station-visitor anatomy diagrams shipped May 2026. Existing 9 (Crew Dragon / Soyuz MS / Cygnus / Starliner / HTV-X / Progress MS / Cargo Dragon / Shenzhou / Tianzhou) are reused as-is at
/diagrams/spacecraft/{id}.svg. Authoring is tiered (see Phase F in §rfc-link / Issue #59) so V1 ships with high-priority coverage and the long tail completes through V1.5 / V2. Tab gracefully no-ops when an SVG hasn't yet been authored for an entry. - CREW — (crewed-spacecraft only) 3-6 notable flights per entry, hand-curated (first flight, last flight, 1–4 historic ones). Each flight shows mission patch + crew portraits. Cross-link to the relevant
/missionsentry per flight. (Notable-flights curated rather than every-flight paginated, to bound editorial scope.) - MISSIONS — list of cross-referenced mission entries from
missions.json(linked_missions: [...]field, curated per fleet entry). Build-time validator cross-checks bidirectionally: every mission's newlaunch_vehicle_idfield must appear in its launcher'slinked_missions. Each mini-card clickable →/missions?id=.... - LEARN — link tiers (intro / core / deep) sourced via the existing link-provenance pipeline (ADR-051). For non-US entries, operator's native-language page first (Roscosmos Russian, CMSA Chinese, JAXA Japanese, ISRO).
Data shape (per entry)
{
"id": "saturn-v",
"name": "Saturn V",
"category": "launcher",
"agency": "NASA",
"country": "United States",
"manufacturer": "Boeing / North American / Douglas",
"first_flight": "1967-11-09",
"last_flight": "1973-05-14",
"status": "RETIRED",
"era": "1960s",
"best_known_for": "Sent humans to the Moon",
"specs": {
"height_m": 110.6,
"mass_kg": 2970000,
"thrust_n": 35100000,
"payload_to_leo_kg": 140000,
"stages": 3
},
"linked_missions": ["apollo11", "apollo12", "apollo13", "apollo14", "apollo15", "apollo16", "apollo17"],
"credit": "NASA Apollo Program imagery archive (PD-NASA)",
"links": [
{ "l": "Wikipedia · Saturn V", "u": "...", "t": "intro" },
{ "l": "NASA · Saturn V Reference", "u": "...", "t": "core" },
{ "l": "Apollo by the Numbers (NTRS)", "u": "...", "t": "deep" }
]
}Locale overlays at static/data/i18n/{locale}/fleet/{id}.json carry editorial copy:
{
"name": "Saturn V",
"tagline": "First of: human-rated heavy-lift launcher",
"description": "The 36-storey rocket that put 24 humans on a translunar trajectory and 12 of them on the lunar surface...",
"best_known_for": "Apollo lunar program · 13 successful launches · zero crew losses on ascent"
}§what-it-must-not-do
- Not a replacement for
/missions. The Mission Catalog remains the primary "what was done" surface; Fleet is the "what was used" complement. Cards on Fleet link to mission detail, they do not duplicate the mission narrative. - Not a duplicate of
/issor/tiangong. Stations on the Fleet page link out to the dedicated explorer routes when relevant. - Not a parts catalogue. We do not list every variant ("Falcon 9 Block 5 Reusable Booster" vs. "Falcon 9 Block 5 Heavy"). One entry per recognisable hardware family.
§metrics
(Soft V1 acceptance signals; to track post-launch.)
- ≥80% of visitors who open a Fleet card visit at least one cross-linked mission via the MISSIONS tab.
- Filter usage: ≥40% of grid sessions apply at least one filter chip (suggests the filter axes match user mental models).
- Category spread: at least 10 different cards opened per session on average (suggests the grid layout invites browsing, not just launcher-hunting).
- ≤5 mission badges render unattributed (license-vetting failure mode).
§rfc-link
See RFC-016 — Spaceflight Fleet · architecture, schema, and dataset boundaries for the technical resolution: schema design, cross-reference strategy, mission-badge / crew-portrait sourcing, anatomy SVG authoring tiers, and phasing.
ADRs spawned by RFC-016 (proposed):
- ADR-052 — Fleet schema + bidirectional cross-reference contract:
fleet/index.json+ per-entry files;linked_missions/linked_sitescurated explicitly; newfleet_refsfield on missions / moon-sites / mars-sites / earth-objects; bidirectional drift validation at build. - ADR-053 — Mission badge + crew portrait sourcing via Wikimedia Commons + agency archives. Per-image provenance via existing pipeline (ADR-046 / ADR-047). Graceful no-op on missing imagery.
- ADR-054 — Fleet i18n: en-US + es at V1 launch (~110 entries × 2 locales = 220 overlay files); remaining 12 locales via existing ADR-033 auto-translate pipeline in v0.6.x slice.
Implementation tracker: Issue #59 with 11 phases (A through K — added Phase K for cross-route bidirectional linking on /missions / /moon / /mars / /earth panels).
PRD-012 · /fleet · May 2026 · Update when scope or principles change