@squawk/procedures

Pure logic library for querying US instrument procedure data sourced from FAA
CIFP (Coded Instrument Flight Procedures). Covers SIDs, STARs, and Instrument
Approach Procedures (IAPs) in a unified ARINC 424 leg model. Look up by
identifier, by airport, by runway, by approach type; expand a procedure into
an ordered leg sequence; or fuzzy-search by identifier and name. Contains no bundled data - accepts
an array of Procedure records at initialization. For zero-config use, pair
with @squawk/procedure-data.
Part of the @squawk aviation library suite. See all packages on npm.
Usage
import { usBundledProcedures } from '@squawk/procedure-data';
import {
createProcedureResolver,
expansionToLineString,
extractLegPoints,
} from '@squawk/procedures';
const resolver = createProcedureResolver({ data: usBundledProcedures.records });
const allSardi = resolver.byIdentifier('SARDI1');
const aalleAtDen = resolver.byAirportAndIdentifier('KDEN', 'AALLE4');
const ilsAtJfk = resolver.byAirportAndIdentifier('KJFK', 'I04L');
const jfkProcedures = resolver.byAirport('KJFK');
const jfk04LApproaches = resolver.byAirportAndRunway('KJFK', '04L');
const allStars = resolver.byType('STAR');
const allIls = resolver.byApproachType('ILS');
const expansion = resolver.expand('KDEN', 'AALLE4');
if (expansion) {
for (const leg of expansion.legs) {
console.log(leg.pathTerminator, leg.fixIdentifier ?? '(no fix)');
}
}
const withTransition = resolver.expand('KDEN', 'AALLE4', 'BBOTL');
const results = resolver.search({ text: 'AALLE', type: 'STAR' });
console.log(results[0]?.procedure.identifier, results[0]?.score);
if (withTransition) {
const points = extractLegPoints(withTransition.legs);
const line = expansionToLineString(withTransition.legs);
}
Consumers who have their own procedure data can use this package standalone:
import { createProcedureResolver } from '@squawk/procedures';
const resolver = createProcedureResolver({ data: myProcedures });
Browser / SPA usage
The resolver factory has no Node-specific imports and ships an explicit /browser subpath for SPAs and edge runtimes. Pair it with @squawk/procedure-data/browser:
import { loadUsBundledProcedures } from '@squawk/procedure-data/browser';
import { createProcedureResolver } from '@squawk/procedures/browser';
const dataset = await loadUsBundledProcedures();
const resolver = createProcedureResolver({ data: dataset.records });
The /browser entry is identical to the main entry; the separate subpath exists so browser support is an explicit, publint-verified part of the public API surface.
API
createProcedureResolver(options)
Creates a resolver object from an array of Procedure records.
Parameters:
options.data - an array of Procedure objects (from @squawk/types).
Returns: ProcedureResolver - an object with the lookup methods described below.
resolver.byIdentifier(identifier)
Looks up every procedure matching a CIFP identifier (case-insensitive). CIFP
identifiers are not globally unique - the same identifier (for example
SARDI1 or I04L) is published separately for each adapted airport, so this
returns all matches. Returns Procedure[].
resolver.byAirportAndIdentifier(airportId, identifier)
Resolves a single procedure by (airport, identifier). Case-insensitive for
both arguments. Returns Procedure | undefined.
resolver.byAirport(airportId)
Returns every procedure (SID, STAR, or IAP) adapted at the given airport.
Case-insensitive. Returns Procedure[].
resolver.byAirportAndRunway(airportId, runway)
Returns procedures at an airport that serve a specific runway. For IAPs, the
match is on the runway field directly. For SIDs and STARs, the match is on a
runway transition named RW<runway> (for example RW04L). Case-insensitive.
Returns Procedure[].
resolver.byType(type)
Returns every procedure of a given type. Pass 'SID', 'STAR', or 'IAP'.
Returns Procedure[].
resolver.byApproachType(approachType)
Returns every IAP of a given approach classification ('ILS', 'LOC',
'LOC_BC', 'RNAV', 'RNAV_RNP', 'VOR', 'VOR_DME', 'NDB', 'NDB_DME',
'TACAN', 'GLS', 'IGS', 'LDA', 'SDF', 'GPS', 'FMS', 'MLS').
Returns Procedure[].
resolver.expand(airportId, identifier, transitionName?)
Expands a procedure into an ordered leg sequence. Without a transition name,
returns the procedure's first common route. With a transition name, merges the
named transition's legs with the common route in flying order:
- SID + enroute exit transition - common route first, then transition.
- SID + runway transition (
RW* name) - transition first, then common route.
- STAR + enroute entry transition - transition first, then common route.
- STAR + runway transition - common route first, then transition.
- IAP + approach transition - transition first, then final approach segment.
The connecting fix between transition and common route is deduplicated when
both segments reference it.
Returns ProcedureExpansionResult | undefined, containing:
procedure - the full Procedure record.
legs - the ordered ProcedureLeg sequence.
resolver.search(query)
Fuzzy-searches procedures across identifier and name. Matching is case-insensitive
and tolerant of prefixes, substrings, subsequences, and small typos. Results are
scored and returned best-match first.
text | string | Search text, matched fuzzily against each procedure's identifier and name |
limit | number | Optional. Maximum number of results. Defaults to 20 |
type | ProcedureType | Optional. Restrict to 'SID', 'STAR', or 'IAP' only |
approachType | ApproachType | Optional. Restrict to IAPs of a given approach classification |
minScore | number | Optional. Minimum match score (exclusive) in [0, 1] a result must reach. Defaults to 0 |
Returns ProcedureSearchResult[], sorted by descending score, each containing:
procedure - the matched Procedure record
score - match strength in [0, 1], where 1 is an exact identifier or name match
matchedField - which field produced the best match: 'identifier' or 'name'
ranges - matched character ranges within the best-matching field's text, for highlighting
const results = resolver.search({ text: 'AALLE', type: 'STAR' });
for (const { procedure, score, matchedField } of results) {
console.log(procedure.identifier, score, `(matched ${matchedField})`);
}
Extracts the ordered drawable points from an expanded leg sequence (the legs
array of a ProcedureExpansionResult). Only legs that terminate at a known fix
contribute a point; legs whose ARINC 424 path terminator ends at an altitude,
DME distance, radial, intercept, or manual event (CA, FA, VA, CD, FD,
VD, CR, VR, CI, VI, FM, VM, and the HA/HM holds) carry no
coordinate and are skipped, so a non-positional leg in the middle of a sequence
leaves a gap. Consecutive duplicate points are suppressed. Returns
ProcedureLegPoint[], each with label, lat, and lon.
expansionToLineString(legs)
Builds a GeoJSON LineString from an expanded leg sequence, ready to render as a
polyline on a map (for example MapLibre or Leaflet). Coordinates follow the
GeoJSON [lon, lat] ordering. Because non-positional legs are skipped (see
extractLegPoints), the line connects only the fix-terminated legs and is an
approximation that omits the non-drawable segments rather than a precise flyable
track. Returns LineString | undefined - undefined when the legs yield fewer
than two drawable points, since a LineString requires at least two positions.