Module real_flight 

Real flights: hpr against the altitude logs of RocketPy’s example rockets, flown in the ERA5 weather of their day (M2.3b, decision ADR-082).

Each RealFlight is a rocket RocketPy’s documentation flies against its team’s log. hpr flies the same rocket (its design under validation/designs/, built from the example’s inputs), on the example’s own thrust file with the example’s burn options, from the example’s rail and site, in the ERA5 file the example reads, with hpr’s own aerodynamics: the way a user would fly it. The log is the reference.

The logs, most of the thrust files and the full weather files carry their own terms, so they are read from the pinned RocketPy checkout under the gitignored refs/ and never committed. What is committed is REPORT_JSON and REPORT_MD: per flight, the log’s apogee and hpr’s, the apogee error, the altitude-trace RMS, and the SHA-256 of every file read. cargo xtask real-flights writes them and --check flies them again; CI, which has no refs/, holds the summary to the rows and the page to the data (RealFlightReport::check_consistent).

What is compared, for each flight:

• Heights: a barometric altimeter reads the standard atmosphere’s altitude of the pressure it measures, less the pad’s, not the height it climbed: on a warm day, less. So hpr’s height is read the same way, from the ERA5 pressure at its center of mass, for a log whose Altimeter is barometric (Barometer), and taken as it is otherwise. Each log’s height column is used as recorded.
• Apogee: the highest height in the log, read up to Log::until_s where the recovery’s pressure transients would otherwise set it, against hpr’s apogee read the same way. The error is hpr’s less the log’s, as a percentage of the log’s.
• Altitude-trace RMS: the log’s heights against hpr’s over the ascent. The two clocks are aligned where each trace first reaches ALIGN_HEIGHT_M, since a log’s zero is its own (armed, launch detected, or power on) and not hpr’s ignition. The RMS is over every log row from there until the first of the two apogees, hpr’s heights linearly interpolated from a GRID_S grid of its dense output. The descent is not compared: its events (which parachute opened, when) are the team’s, and one of these flights lost its main.

Two diagnostic flights, not predictions, say where a miss may come from: the same flight on the example’s own drag, and where the example reshapes its thrust file, on the file as recorded. Where a log keeps its pressure or the flight a satellite altitude, the report holds the barometric reading against them. Each row carries the SHA-256 of its flight’s entry in FLIGHTS, so CI sees an input change the report hasn’t caught up with.

The mean absolute apogee error is reported against the APOGEE_TARGET_PERCENT target of docs/VALIDATION.md; it is a target, not a gate. A flight outside it is an outlier, and each outlier carries its explanation in RealFlight::explanation.

Structs

Barometer

A barometric altimeter on a pad, in the air of a day: it reads the standard atmosphere’s altitude of the day’s pressure where it is, less that at the pad, H(p(z)) − H(p(z₀)) (Ussa76::pressure_altitude_m).

FileRead

A file read and its SHA-256.

FlightRow

One flight’s result, as the report keeps it.

Gnss

Where a flight’s satellite altitude is and how to read it.

Log

Where a flight’s altitude log is and how to read it.

RealFlight

One logged flight.

RealFlightReport

The real-flight report.

RecordedThrust

The flight on the thrust file as recorded, without the example’s reshape.

Summary

What the report sums up.

TraceComparison

What the trace comparison gives.

Enums

Altimeter

What a log’s height is.

ExampleDrag

The drag the example flies, as its notebook gives it: the second, diagnostic flight’s.

Explanation

Why a flight’s apogee misses the log’s by more than APOGEE_TARGET_PERCENT: a claim the report’s own numbers are checked against (RealFlightReport::check_consistent), so a change that makes it false fails the check, with the words that argue it.

RealFlightError

Why a real flight could not be read, flown or reported.

Constants

ALIGN_HEIGHT_M

The height each trace’s clock is aligned at, m above its start.

APOGEE_TARGET_PERCENT

The target for the mean absolute apogee error, per cent (docs/VALIDATION.md, “Principles”).

FLIGHTS

The flights, in the order the report lists them.

GRID_S

The spacing of hpr’s heights the trace is compared against, s.

MASS_FIXTURE

The design fixture that records each example’s own thrust file and burn options.

REPORT_JSON

The report, as data.

REPORT_MD

The report, as a page.

ROCKETPY

The pinned RocketPy checkout the logs, thrust files and weather files are read from.

Functions

compare_traces

The ascent of hpr (time since ignition, height) against the log’s, each aligned where it first reaches ALIGN_HEIGHT_M, over the log’s rows from there to the first of the two apogees.

fly

Flies one flight and compares it with its log.

parse_log

A log’s rows as (time, height in meters), in file order.

parse_thrust

A thrust file as RocketPy 1.13.0 reads it, with the example’s burn options.

run

Flies every flight in FLIGHTS and builds the report.

summarise

The summary of rows.