Module issues 

Warnings for known errors in hpr’s drag, each by its issue number: where a flight’s speed and its design’s shape meet the condition under which a number is known to read wrong (ADR-163 §4, ADR-180).

Drag that reads high makes three numbers flatter than they are: the apogee reads low against a waiver’s ceiling; the top speed reads low, so the flutter margin and the largest dynamic pressure look better; the drift reads small. Each warning names them. Every flight still flies; a warning only says which numbers to trust less, and which way they lean. A flight flown on a drag of its own (a table or a model in place of hpr’s) meets none of these.

issue	the error	the condition
#67	the closed-form cone’s pressure drag reads high, transonic	a nose or a shoulder whose shape takes it (takes_cone_formula), past Mach 0.8
#68	base drag reads high from Mach 0.8 to 1.2, low from 1.5	every rocket, past Mach 0.8
#70	a sharp fin section’s drag reads high, supersonic	an Airfoil fin set, past Mach 1
#72	a steep boattail’s drag reads high, supersonic	a boattail steeper than 10°, past Mach 1
#222	supersonic pressure drag about twice OpenRocket’s	an Ogive nose or an Airfoil fin set, past Mach 1
#73	a boattail’s drag by Niskanen’s subsonic rule, up to +41.7% on a measured one	a boattail steeper than 9.46° (SUBSONIC_BOATTAIL_RULE_RAD), any flight
#18	skin friction taken as fully turbulent reads high on a surface smooth enough for a laminar run	every flight (friction_issue_warnings)

Others warn where the margin reads high (stability_issue_warnings, layout_stability_issue_warnings): a forward-swept fin past Mach 1 (#64), fin sets sharing a station (#325), a freeform fin set at any speed (#326, ADR-190), the supersonic switches (#87, #120, #121) and #172 on every flight (ADR-189).

Two more warn where a part flies on its own after a separation, with only its devices’ drag (separated_part_issue_warnings): a booster (#179), and a part that starts with nothing open (#354). They read the flight’s bodies, not its drag, so a flight on a drag of its own meets them too.

Each Mach edge is exclusive, as the envelope’s are (crate::envelope): a flight whose top Mach number is exactly at an edge raises nothing, and a NaN top Mach number raises every warning whose shape the design has, so a broken number can’t hide one.

Structs

IssueWarning

A known issue a flight meets, with the flight’s top Mach number and the parts whose shape meets its condition.

Enums

KnownIssue

A known error in hpr’s drag or stability that a flight can meet.

Constants

BASE_DRAG_HIGH_MACH

Where base drag starts to read high: Mach 0.8 (issue #68: Fleeman’s formula gives 0.225 at Mach 0.9 where MIL-HDBK-762’s measured data give 0.156).

BASE_DRAG_HIGH_TOP_MACH

The last Mach number where base drag is measured to read high: 1.2 (0.208 against MIL-HDBK-762’s 0.194, issue #68). Past it a flight’s warning adds the low side (BASE_DRAG_LOW_MACH); between the two the sign is unmeasured.

BASE_DRAG_LOW_MACH

Where base drag is measured to read low: from Mach 1.5 (5% under Love’s correlation, NACA TN 3819, at Mach 1.5, 17% at 2.0, 14% at 3.0; issue #68). There the apogee reads high.

FINS_WITHOUT_INTERFERENCE

The most fins that one station can hold before the fin–fin interference factor drops below 1: four (Niskanen 2009 table 3.3, hpr_aero::fins::fin_count_factor). Fin sets at one station with more than this between them are counted apart by hpr and together by OpenRocket (issue #325).

FIN_SETS_AT_ONE_STATION_CAL

How much of the margin gap on OpenRocket’s Pods–airframes and winglets example counting fin sets apart explains, calibres: about 0.029 of 0.071 to 0.076 (issue #325).

FORWARD_SWEEP_MACH

Where a forward-swept fin’s warning starts: Mach 1 (ADR-188). Its measured error is a normal-force slope that rises by up to 7.7% past linear theory’s start, Mach 1.2 (hpr_aero::fins::SUPERSONIC_START_MACH), peaking up to 0.37 past it (issue #64); the warning starts at the lowest supersonic Mach number, below that rise. The transonic join into linear theory starts at Mach 0.8 (hpr_aero::fins::TRANSONIC_START_MACH); below Mach 1 the error isn’t measured.

FREEFORM_FIN_MARGIN_CAL

The share of the static margin, calibres, that a kinked freeform fin’s center of pressure takes on OpenRocket’s Pods–airframes and winglets example, where hpr’s sits 1.6 mm aft of OpenRocket 24.12’s (issue #326). Unprobed on other outlines, so every freeform fin set warns.

LAMINAR_FRICTION_PERCENT

How much of the friction a laminar run takes off on RocketPy’s Calisto at Mach 0.3, where hpr takes it fully turbulent (issue #18): Barrowman 1967’s transitional term 1700/R (eq. 4-6) at R = 1.8e7, against Niskanen 2009’s smooth turbulent coefficient 1/(1.50 ln R − 5.6)² (eq. 3.78), in percent. Barrowman gives no rule for when a surface is too rough to stay laminar, so every flight on hpr’s drag warns.

MARGIN_HIGH_BOUND_CAL

How far the static margin read high against OpenRocket 24.12, calibres: the largest gap on the private designs, 0.1108 (four designs read 0.0350 to 0.1108 calibres more stable in hpr, none with a measured cause; How far to trust the margin on the stability page, issue #172).

STEEP_BOATTAIL_RAD

A boattail steeper than this, in radians, warns past SUPERSONIC_DRAG_MACH: 10°, the steepest that issue #72 measured inside its spread (−6.3% to +17.4% at 10° and below). It measured 15° at +13.5% to +50.8% and 16° at +26.4% to +54.1%; between 10° and 15° is unmeasured, so the warning takes it in rather than leave a high drag unwarned.

SUBSONIC_BOATTAIL_RULE_RAD

The steepest boattail that Niskanen’s subsonic rule gives no drag, rad: where its length ratio γ = l/(d₁ − d₂) is 3, so atan(1/6), 9.46° (Niskanen 2009 eq. 3.88, hpr_aero::drag::boattail_factor). A steeper one takes a share of base drag below Mach 0.8, which read from −40.8% to +41.7% on Cubbage’s measured 16° boattails and high on the Arcas Robin’s 15° one (issue #73); between 9.46° and 15° is unmeasured, so the warning takes it in.

SUPERSONIC_DRAG_MACH

Where the supersonic drag warnings start: Mach 1 (issues #70, #72 and #222). Their measured gaps start at Mach 1.0 to 1.5; the warning starts at the lowest.

SUPERSONIC_SWITCH_MACH

Where the supersonic body switches start to matter: Mach 1.2, the earliest the shock-expansion method joins slender-body theory (hpr_aero::SUPERSONIC_JOIN_START_MACH).

TRANSONIC_NOSE_DRAG_MACH

Where the closed-form cone’s transonic pressure drag starts to read high: Mach 0.8 (issue #67: +87% at Mach 0.8 and +105% at 0.85 against Stoney’s measured 3:1 cone, NASA TR R-100; 2 to 9 times MIL-HDBK-762’s 3:1 tangent ogive from Mach 0.9 to 1.2; still +15% at Mach 1.5).

Functions

friction_issue_warnings

The friction issue a flight on hpr’s own drag meets: #18 whenever it has a top Mach number, at any speed and on any finish, since Barrowman 1967 gives no rule for when a surface is too rough to stay laminar (LAMINAR_FRICTION_PERCENT). Apart from issue_warnings, which reads the design’s shape.

issue_warnings

The issues a flight meets: one whose top Mach number is max_mach, of a rocket whose parts are parts, each an id and its part, flown on hpr’s own drag. In KnownIssue’s order, each listing the parts that meet its condition. A flight with no top Mach number meets none.

layout_issue_warnings

issue_warnings over every part of layout, pods’ included.

layout_stability_issue_warnings

The stability issues a design’s shape meets, on a flight whose top Mach number is max_mach (ADR-189): #64 for its forward-swept fin sets past FORWARD_SWEEP_MACH, then #325 for its fin sets that share a station, then #326 for its freeform fin sets at any speed (FREEFORM_FIN_MARGIN_CAL). They are errors in hpr’s normal force, not its drag, so a flight on a drag of its own meets them and one on a normal-force table of its own doesn’t, as with stability_issue_warnings. A flight with no top Mach number meets none.

separated_part_issue_warnings

The separated parts’ issues a flight meets (ADR-200), read from the bodies that flew on their own (FlightResult::bodies), whatever the rocket’s drag: each part’s descent is a point under its open devices (crate::recovery), never the rocket’s drag.

stability_issue_warnings

The stability issues a flight meets (ADR-181): one whose top Mach number is max_mach, whose aerodynamics stopped the supersonic body run for fallback (hpr_aero::AeroModel::supersonic_fallback), and whose smallest static margin is min_static_margin. Issues #87, #120 and #121 when their switch stopped the run and the flight is past SUPERSONIC_SWITCH_MACH, naming the component; #172 whenever the flight has a smallest static margin. A flight with no top Mach number meets none.