Flight Model & Stores

The aircraft flight model (FM_*) and hardpoint/stores management (HARD_*) — how the engine turns pilot/AI control inputs and a loadout into per-frame aircraft state: gear, flaps, wing sweep, thrust vectoring, weapon-bay doors, throttle, fuel burn, weight, and the rearm/repair bookkeeping behind it. All virtual addresses are from the shipping binary. Fixed-point values use the engine's standard s8.8 format (divide by 256 for real units) unless noted.

Scope: this is the reconstruction-program flight-model subsystem (#212) — FM_* + HARD_*, 0x451480–0x454800. The broader physics story it used to bundle lives in adjacent subsystems: collision (_Collision, COL_*) is

222, weapons/projectiles (PROJ_*, the seeker/ballistics model) is #215, and

terrain height/queries (T_*) is #221. The sections below that describe those (§ Terrain Collision, § PROJ dispatch, § Collision Detection) are provisional and migrate to those docs as they land.

Provenance: Ghidra static analysis of the game executable with FA.SMS symbols applied; every flight-model symbol here is recorded in the symbol database and applied to the Ghidra project. Confidence markers follow spec-authoring.md: confirmed · inferred · unknown.

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Globals — Key Physics State

These globals are polled by nearly every function in the flight model. All are per-player (the flight model operates on the current object selected by _curId).

Global	Address	Role
DAT_0050ceb4	0x50CEB4	Current airspeed (s16.8 knots)
DAT_0050ce9f	0x50CE9F	Pitch angle (s16, engine units)
DAT_0050ce95	0x50CE95	Altitude (absolute, engine units — 1 unit = 1 ft)
DAT_0050ceaf	0x50CEAF	Ground elevation below aircraft
DAT_0050ce9d	0x50CE9D	Heading angle
DAT_0050cea1	0x50CEA1	Bank angle
DAT_0050ce91	0x50CE91	X world position
DAT_0050ce99	0x50CE99	Z world position
DAT_0050d06e	0x50D06E	Current throttle position (s16.8, smoothed)
DAT_0050d072	0x50D072	Target throttle % (0–100)
DAT_0050d07c	0x50D07C	Internal fuel quantity (s16.8)
DAT_0050d01b	0x50D01B	G-load (s16.8, 0x100 = 1 G)
DAT_0050d08c	0x50D08C	Stall state byte (0=normal, 1=warning, 2=stall, 3=deep stall, 4=snap)
DAT_0050cfef	0x50CFEF	HUD/state flags word — bit 0x40 = gear down, bit 0x20 = afterburner, bit 0x80 = low fuel, bit 0x200 = bay open
_onTheGround	(SMS)	Boolean: aircraft on ground

---

1. Flight Model Overview

The player flight model runs inside _FMFlight@0. For NPC aircraft the same PT data is used but fuel burn goes through @FMBurnNPCFuel@4.

_FMFlight@0 — 0x47B020

FA.SMS name: _FMFlight@0

Main per-frame flight update for the player aircraft. Called from the flying loop. Entry sequence:

1. _FMAircraftSetup_0() — copies PT type fields to the working globals (see §7).
2. _F24ToPA_4(DAT_0050d013) → DAT_0050ce9f — converts stick pitch to pitch angle.
3. _SetThrottle_4(_throttle) — applies throttle input.
4. _BurnFuel_0() — deducts fuel for this tick.
5. Gear, gear pitch, weapon bay, thrust vector, and wing sweep update calls.
6. Stall detection: compares DAT_0050ceb4 >> 8 against _oneGStallSpeed__3JA. State machine transitions through DAT_0050d08c values 0→1→2→4; state 2 applies control authority reduction proportional to (stallSpeed - currentSpeed) / stallSpeed.
7. Stick inputs fed through _StickInput_28 for pitch (DAT_0050d01b), roll (DAT_0050cfff), yaw (DAT_0050d007), and thrust-vector nozzle (DAT_0050d12f / DAT_0050d133).

@FMFuelConsumption@4 — 0x451E50

FA.SMS name: @FMFuelConsumption@4

int _FMFuelConsumption_4(int throttle_pct)
{
    if (100 < throttle_pct)
        return (int)DAT_0050d3cb << 8;      // afterburner fuel flow (PT field)
    return (DAT_0050d3c9 * throttle_pct * 0x100) / 100;  // mil power flow × pct
}

Parameters: throttle_pct — integer 0–100 (or >100 for afterburner).
Returns: fuel flow rate in s16.8 units per tick.
Reads: DAT_0050d3c9 (mil power fuel flow, PT field), DAT_0050d3cb (AB fuel flow, PT field).
Callers: _PLANECheckFuel@0 (0x49FB70), FUN_00451e8b (0x451E8B — the player fuel tick).

_BurnFuel@0 — 0x451E80

FA.SMS name: _BurnFuel@0

Deducts fuel from the internal tank (DAT_0050d07c) and from external hardpoint stores (via _HARDFindStore_12). Called directly by _FMFlight@0 (0x47B020) and @FMBurnNPCFuel@4 (0x452050). The player tick wrapper FUN_00451e8b calls _FMFuelConsumption_4 to get the current flow rate and deducts 5 units per 5-tick service interval; when an external tank empties it is automatically jettisoned and the HUD message "Empty external tanks automatically jettisoned" is played with the _BOMB_11K sound.

@FMBurnNPCFuel@4 — 0x452050

FA.SMS name: @FMBurnNPCFuel@4

NPC fuel burn. param_1 is the NPC's current fuel quantity. Computes a throttle percentage from the fuel level relative to PT thresholds (DAT_0050d0cb / DAT_0050d0cf), smooths towards the target via _MatchF24_12, then calls _BurnFuel_0(). Also triggers the afterburner HUD flag (bit 0x20 of DAT_0050cfef) when fuel is critically low and the PT has an afterburner (DAT_0050d3bb != 0).

---

2. Aerodynamic Parameters

Stall

Symbol	Address	Role
?oneGStallSpeed@@3JA	0x54B72C	1-G stall speed (knots, integer) — threshold for stall warning
?stallVol@@3GA	0x5718E4	Stall warning audio volume
?stallString@@3PADA	0x4EC9E8	Stall text string pointer
?stallWarningString@@3PADA	0x4EC9F0	Stall-warning text string pointer
?liftFailString@@3PADA	0x4ECA08	Lift-fail text string pointer

Stall onset: _FMFlight@0 checks (DAT_0050ceb4 >> 8) <= _oneGStallSpeed__3JA + 25. The margin of 25 knots above 1-G stall speed is the warning threshold.
Stall sounds: _STALL_5K (looped) at full _stallVol during stall state 2; _STALLWR_5K (looped) at 55% volume during state 1 (warning).

Flight envelope check uses _CheckFlightEnvelope_8 (reads DAT_0050d32a–DAT_0050d32c for the altitude-band range), _GetFlightEnvelope_4, and _EnvelopeSpeedLimits_16. Return codes from _CheckFlightEnvelope_8: 0 = normal, 1 = stall warning, 2 = stall, 3 = deep stall / snap.

Turn Rate and G

Function	Address	Role
_COTurnRate@0	0x4780D0	Returns current sustained turn rate. For aircraft (_cg == 4) calls _GToTurn_8(PT.brv[5], airspeed); for ground vehicles returns DAT_0050d2c5.
_COBankRate@0	0x478090	Returns current bank rate. For aircraft with _cg == 4 returns PT.brv[1] * 0xB6; caps at 0x7FFF.
_GToTurn_8	(SMS)	Converts G-load + airspeed to turn-rate. Used in _FMFlight@0 for DAT_0050d003 (current turn demand).
_MaxGAtAlt_0	(SMS)	Returns the flight-envelope index for max-G altitude band; used to look up corner speed via _GetFlightEnvelope_4.
_COGPullDrag@0	0x4784A0	Returns G-induced drag increment. Computes (DAT_0050d3d3 * (gPullLoad * DAT_0050d3e3 / 100 + 100)) / 100.

_COGPullDrag@0 reads two PT drag fields: DAT_0050d3d3 (base induced drag coefficient) and DAT_0050d3e3 (G-drag scaling factor). DAT_0050d0dd and DAT_0050d0df hold the accumulated G load across pitch and yaw axes.

Thrust

@COThrust@4 (0x478190) returns DAT_0050d3b7 (mil thrust) or DAT_0050d3bb (AB thrust) depending on the param_1 AB flag. In multiplayer with _gameMultiPrefs bit 0x10 set, thrust is halved for AI opponents.

Mach

@SpeedOfSound@4 (0x412780) is present in FA.SMS. Mach number is not stored as an explicit global; the engine scales indicated airspeed from knots using the BRF fixed-point convention (6,076 units = 1 nm; 1 unit = 1 ft).

Wing Sweep

_FMUpdateWingSweep@0 (0x4515E0) — for variable-sweep aircraft. Reads _COMinSpeed_0() and _COMaxSpeed_0(), linearly interpolates sweep position _DAT_0050d021 from 0 to 0x7FFF across the speed range [minSpeed, (minSpeed + maxSpeed)/2].

---

3. _PROJProc Virtual Dispatch

Wrapper — FUN_004C1F10 (0x4C1F10)

No FA.SMS name. Confirmed to read entity field +0x4 from the PROJ entity. Callers list in the Ghidra output is empty — the wrapper is invoked indirectly through the object-update loop's utilProc pointer, not via a direct call chain that Ghidra could trace statically. The architecture.md table maps _PROJProc as the utilProc symbol for .JT projectile files.

Dispatch — 0x4C1F50 and PROJMoveProc — 0x4C11B0

Both addresses returned NOT FOUND in the Ghidra analysis; neither contains a decompilable function at those exact VAs. They are likely thunks or mid-function entry points in the PROJ update path. The closest named functions in the vicinity are:

VA	Name	Notes
0x4C1120	_PROJSpeed@8	Computes clamped projectile speed
0x4C1170	_PROJEngineState@0	Returns 0/1/2 for motor phase (boost / coast / burnout)
0x4C20C0	_PROJHit@8	Hit detection; reads entity +0x55
0x4C2170	_PROJFire@16	Fire initialisation; reads entity +0x50
0x4C26F0	_PROJFireSound@4	Fire sound; reads entity +0x7F
0x4C2860	_PROJInFOV@40	FOV check; reads entity +0x50

_PROJSpeed@8 — 0x4C1120

int _PROJSpeed_8(int proj_type_ptr, int throttle_pct)
{
    int spd = (*(byte*)(proj_type_ptr + 0x115) * (throttle_pct >> 8)) / 100;
    if (spd < *(short*)(proj_type_ptr + 0xFB)) spd = *(short*)(proj_type_ptr + 0xFB);
    if (spd < *(short*)(proj_type_ptr + 0x67)) spd = *(short*)(proj_type_ptr + 0x67);
    if (*(short*)(proj_type_ptr + 0x6B) < spd)  spd = *(short*)(proj_type_ptr + 0x6B);
    return spd;
}

Reads three PROJ_TYPE speed fields at +0x67 (min speed floor), +0x6B (max speed cap), +0xFB (boost minimum), and +0x115 (throttle scaling byte).

_PROJEngineState@0 — 0x4C1170

Returns the motor phase for the current projectile: - 0 — boost phase (time since fire < ram0x0050d367) - 1 — sustain phase - 2 — coast / burnout (time since fire >= DAT_0050d369)

Reads DAT_0050cf68 (fire timestamp) and ram0x0050d367 / DAT_0050d369 (phase durations from the JT type). Turn rates in _COTurnRate@0 for _cg == 6 (missile) dispatch through this state machine: state 0 returns 0, state 1 returns DAT_0050d36d, state 2 returns _DAT_0050d36f.

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4. Terrain Collision

_GetGround@0 — 0x47AF20

FA.SMS name: _GetGround@0. Reads entity field +0x1 (confirmed from offset scan). Returns the ground elevation at the current object's position. Called by terrain avoidance and landing logic throughout the flight model.

The Ghidra script queried 0x47AF70 under the label _GetGround@0 but found _FMSetTV@8 at that address — the correct VA from the offset scan is 0x47AF20.

_FMSetTV@8 — 0x47AF70

FA.SMS name: (none found; internal FM helper). Configures thrust-vector nozzle direction flags _dirTVY / _dirTVZ and the corresponding _onTVY / _onTVZ booleans. Refuses to activate thrust vectoring while _OnTheGround_0() is true. Callers: ?TVKey@@YIGG@Z (0x413C70), @FlightKey@4 (0x414690), _FMFlight@0 (0x47B020), _FlightMenu (0x474800), _FMResetTV@0 (0x47B000).

_T_Info@24 — 0x4ABAB0

FA.SMS name: _T_Info@24. Returns terrain elevation at a world-space point. Called by @COLPitchToAvoidTerrain@0 to find the ground level 250 ft ahead of the aircraft:

iVar1 = _T_Info_24(0, NULL, look_ahead_pos, NULL, 0, 0);
clearance = altitude - iVar1 - DAT_0050d2dd;

DAT_0050d2dd is the terrain avoidance margin.

_COLPitchToAvoidTerrain@0 — 0x42DF80

Computes the pitch command needed to avoid terrain. Projects a point 250 ft ahead using _Rotate2_8 and the current heading DAT_0050ce9d, then queries _T_Info_24. The required pitch-up is iterated from −90° to +90° (−0x3FFC to +0x3FFC in engine units) in 0x38E increments until vertical clearance is positive. Returns the cached pitch value DAT_0050ceda; the cache expires based on whether the aircraft is in a critical regime (DAT_0050ce9f < -0x71C or terrain clearance < 0xBB800 = ~3 nm), refreshed every 1 vs. 4 ticks accordingly.

do_use_terrain_detail — 0x4D2344 and expandTerrain — 0x50E145

Neither address resolved to a function in the Ghidra output. _expandTerrain (the global, not a function) is used as a flag at 0x50E145-vicinity code: it is set to 1, _coarse is set to 1, a terrain dispatch via vector_table fires, then both are cleared. This confirms _expandTerrain is a render-quality hint that forces the terrain renderer to emit extra-detail geometry for the current tick.

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5. PROJ_TYPE Physics Fields — Offset Scan 0x50–0x7F

Offsets confirmed used by projectile functions. All relative to the PROJ_TYPE base pointer (the .JT BRF data pointer passed as param_1).

Offset	Confirmed by	Likely field
+0x50	_PROJFire@16, _PROJInFOV@40, FUN_004c2b5a	Projectile class / type word
+0x55	_PROJHit@8	Hit-detection radius or damage flags
+0x57	FUN_004c0a9d	Proximity fuze or arming distance
+0x60	FUN_004c24b0	Seeker or guidance parameter
+0x64	_PROJSpeed@8	Speed parameter block (also confirmed as @FMFuelConsumption@4 offset in throttle context)
+0x67	_PROJSpeed@8	Minimum speed (s16)
+0x6B	_PROJSpeed@8	Maximum speed (s16)
+0x7F	FUN_004c1c10, _PROJFireSound@4	Fire sound index or audio flags

The offset-0x64 collision between @FMFuelConsumption@4 and _PROJSpeed@8 is not a conflict: @FMFuelConsumption@4 uses global DAT_0050d3c9 (mapped from the PT type area at 0x50D3xx) while _PROJSpeed@8 works on a passed proj_type_ptr. They happen to share the same local offset within their respective type structs.

---

6. Collision Detection

_Collision@56 — 0x42B800

FA.SMS name: _Collision@56. The main broad-phase + narrow-phase collision query.

Signature:

void _Collision_56(
    ushort   obj_id,         // param_1  — object to test against
    char    *last_hit_cache, // param_2  — optional per-object cache (NULL = no caching)
    byte     flags,          // param_3  — bit 0x80 = use cache; bits 1/4/8/10 = test modes
    int     *pos_a,          // param_4  — start position [x,y,z]
    int     *pos_b,          // param_5  — end position [x,y,z]
    int      radius,         // param_6  — swept-sphere radius
    short    sweep_len,      // param_7  — sweep length hint
    ushort   col_flags,      // param_8  — bit 0x1 = terrain test; bit 0x4 = mesh test; bit 0x200 = no-radius
    ushort  *result_type,    // param_9  — OUT: 0=miss, 0xFFFF=terrain, else mesh-hit index
    int     *hit_pos,        // param_10 — OUT: hit world position [x,y,z]
    ushort  *surface_id,     // param_11 — OUT: mesh surface ID (optional)
    ushort  *poly_id,        // param_12 — OUT: polygon ID (optional)
    short   *hit_normal,     // param_13 — OUT: surface normal (via _COLSetAngle_8)
    int      cache_write     // param_14 — if non-zero, writes back to last_hit_cache
);

When col_flags & 1 is set (terrain test), calls _COLFlatGround__YIDJPAUF24_POINT3__00_Z for the coarse flat-terrain check, then optionally _T_GetLeaf_12 for the detailed terrain leaf hit. When col_flags & 4 is set, calls FUN_0042c9b0 for the mesh sweep. When col_flags & 0xA is set, calls FUN_0042c840 for the broad-phase AABB sweep.

The cache (last_hit_cache) skips the full geometry query if the object position matches the previous tick's stored values; cache validity is bounded by _currentTicks + 1 or _currentTicks + 0x100 depending on the hit object's altitude and armor state.

?IntersectT@@YAJPAUF24_POINT@@JJ@Z — 0x447970

FA.SMS name (demangled): IntersectT(F24_POINT*, long, long).

Ray-sphere intersection test. Takes a point record, a minimum distance, and a maximum distance; returns the intersection parameter along the ray or 0 on miss.

int _IntersectT(int *point, int t_min, int t_max)
{
    if (t_min <= point[1])
    {
        int t = _MultDiv32_12(*point >> 8, t_min >> 8, point[1] >> 8);
        if (t < t_max) return t;
    }
    return 0;
}

Terrain flat-ground test — _COLFlatGround__YIDJPAUF24_POINT3__00_Z

Called by _Collision@56 with the object ID, start/end positions, and an output buffer for the hit point. Returns non-zero on terrain hit; if detailed terrain (_th != 0) is active, calls _T_GetLeaf_12 to get the surface classification byte from the T2 tile, which is then passed to FUN_0042de60 for the landing/damage event.

---

7. PT_TYPE (Aircraft Performance Type) — Field Mapping

_FMAircraftSetup@0 (0x47A690) copies PT type data into the working globals at 0x50D3xx and 0x50D38x. This copy is the _cgt type-record mirror: it is byte-for-byte at base 0x50D268, so a global DAT_[0x50D268 + X] reads exactly PT offset X. The source offsets below are therefore DAT − 0x50D268; the 65-word aero block (0xCA–0x14B) is fully mapped in PT.md § The 65-word aerodynamic block.

Global (after setup)	PT offset	Confirmed by	Role
DAT_0050d3b5	0x14D	FUN_00451e8b	Afterburner spool-up time
DAT_0050d3b7	0x14F	@COThrust@4	Mil-power thrust (= military_thrust)
DAT_0050d3bb	0x153	@COThrust@4, @FMBurnNPCFuel@4	AB thrust (= afterburner_thrust; 0 = no AB)
DAT_0050d3bf	0x157	FUN_00451e8b	Throttle ramp-down (= throttle_accel)
DAT_0050d3c1	0x159	FUN_00451e8b	Throttle ramp-up (= throttle_decel)
DAT_0050d3c3	0x15B	_FMInitPlane@8	Min nozzle angle (= tv_min_angle)
DAT_0050d3c5	0x15D	_FMInitPlane@8, _ThrustSupport@0	Max nozzle angle (= tv_max_angle; 0 = no TVC)
DAT_0050d3c7	0x15F	_FMUpdateThrustVector@0	Nozzle slew rate (= tv_speed)
DAT_0050d3c9	0x161	@FMFuelConsumption@4	Mil-power fuel flow (= fuel_consumption_mil)
DAT_0050d3cb	0x163	@FMFuelConsumption@4	AB fuel flow (= fuel_consumption_ab)
DAT_0050d3cd	0x165	_FMInitPlane@8	Initial/full fuel load (= fuel_capacity)
DAT_0050d3d3	0x16B	_COGPullDrag@0	G-induced drag base coefficient (= g_drag)
DAT_0050d3db	0x173	_FMInitPlane@8	Gear-up spawn flag (PT.md: gear_drag)
DAT_0050d3e3	0x17B	_COGPullDrag@0	G-drag scaling factor (= g_drag_loaded)
DAT_0050d3e5	0x17D	_FMUpdatePlaneFields@0	Damage drag penalty (PT.md: gear_pitch)
DAT_0050d32a	0xC2	_FMUpdatePlaneFields@0	Neg-G envelope count (= neg_g_count; low altitude band)
DAT_0050d32c	0xC4	_FMUpdatePlaneFields@0	Pos-G envelope count (= pos_g_count; high altitude band)
DAT_0050d322	0xBA	_FMInitPlane@8, _FMUpdatePlaneFields@0	PT capability flags (= carrier_flags; bit 3 = carrier, bit 0x1C = TVC, bit 0x400 = snap stall)
DAT_0050d3a8	0x140	_FMUpdateGearPitch@0	Gear-down pitch-trim authority (aero word 59, × 0xB6)

The flight-envelope data (_GetFlightEnvelope_4, _EnvelopeSpeedLimits_16, _StallSpeed@4) is indexed by altitude band (integer 0–DAT_0050d32c). Each envelope entry holds a min speed, a max (corner) speed, and a stall speed; the interpolation in _FMUpdatePlaneFields@0 produces DAT_0050d0d7 (min safe speed) and DAT_0050d0d9 (best turn speed) every game tick.

_StallSpeed@4 (0x49D1D0) is a thin wrapper:

uint _StallSpeed_4(short *envelope_entry)
{
    uint spd;
    _EnvelopeSpeedLimits_16(envelope_entry, &spd, NULL, NULL);
    return max(spd, 1);
}

---

8. Dark Zone 0x4D0000–0x4EFFFF

This range is the 3D renderer and rasteriser — not a physics dark zone in the traditional sense. It has no FA.SMS symbols but contains dense, hand-optimised x86. Notable functions found:

VA	Internal name	Role
0x4D028C	FUN_004d028c	Polygon clip / projection kernel. Takes a packed shift word; applies the 3×3 rotation matrix (m1–m9, _scaled_matrix) to a scaled vertex and tests all six clip planes. Returns a signed distance for the determining clip edge.
0x4D0494	get_sort_dist	Painter's-algorithm sort key. Computes |xv32| + |yv32| + |zv32| using abs-and-add approximation plus a per-object size bias from *(ushort*)(EDI - 0xC) * 0x100.
0x4D057C	_GRAddBrentObj@40	Adds a BRF object to the render list. Transforms object-relative position to viewer-relative, scales, calls FUN_004d028c for the clip test, calls get_sort_dist, then writes a 0x30-byte sort entry to obj_ptr / cur_sort_ptr.
0x4D0798	FUN_004d0798	BRF shape renderer. Saves the rotation matrix and viewer-relative components (_xv, _yv, _zv), calls _WRSetRemaps_8 for palette remapping, calls FUN_004ce784 for the perspective divide, dispatches to the shape-type draw routine via vector_table, then restores state.
0x4D1694	FUN_004d1694	Terrain object render entry. Computes absolute viewer-relative delta (*ESI - __viewer_x/y/z), shift-normalises, applies the rotation matrix, and dispatches to the terrain polygon pipeline.
0x4D715A	_DirectDrawCreate@12	Thin thunk to DirectDrawCreate Win32 API — marks the start of the DirectDraw IAT stub block.

Key renderer globals in this range:

Global	Role
_scaled_matrix, m2–m9	Current 3×3 rotation matrix (s16 fixed-point)
_xv, _yv, _zv	Current vertex in viewer space (s16)
_xv32, _yv32, _zv32	Same in s32 for high-precision paths
__viewer_x/y/z	Camera world position
obj_ptr / cur_sort_ptr	Write cursors into the render / sort list
_expandTerrain	Set to 1 during the terrain detail render pass
_coarse	Set to 1 alongside _expandTerrain for the detail pass
_overflow	Set to 0xFFFF when a vertex overflows the clip range
axis_check_type	Selects the axial clip variant via PTR_LAB_004d04dc

_expandTerrain and _coarse are not function VAs — they are boolean globals toggled around the terrain dispatch call. The query for function expandTerrain @ 0x50E145 found them being set at that address as part of a larger terrain-update function that builds a terrain command buffer before dispatching through vector_table.

---

Summary — Function Quick Reference

VA	FA.SMS name	Section
0x42DF80	@COLPitchToAvoidTerrain@0	§4
0x42B800	_Collision@56	§6
0x447970	?IntersectT@@YAJPAUF24_POINT@@JJ@Z	§6
0x451E50	@FMFuelConsumption@4	§1
0x451E80	_BurnFuel@0	§1
0x452050	@FMBurnNPCFuel@4	§1
0x47AF20	_GetGround@0	§4
0x47AF70	_FMSetTV@8	§4
0x47B020	_FMFlight@0	§1
0x478090	_COBankRate@0	§2
0x4780D0	_COTurnRate@0	§2
0x478190	@COThrust@4	§2
0x4784A0	_COGPullDrag@0	§2
0x4515E0	_FMUpdateWingSweep@0	§2
0x4ABAB0	_T_Info@24	§4
0x49D1D0	_StallSpeed@4	§7
0x49FB70	_PLANECheckFuel@0	§1
0x4C1120	_PROJSpeed@8	§3
0x4C1170	_PROJEngineState@0	§3
0x4C1F10	FUN_004c1f10 (PROJ wrapper)	§3
0x4D028C	FUN_004d028c (clip kernel)	§8
0x4D0494	get_sort_dist	§8
0x4D057C	_GRAddBrentObj@40	§8
0x4D0798	FUN_004d0798 (shape renderer)	§8

Update flow

Each frame, the object system services the aircraft entity; for a player/AI plane the control inputs (throttle, stick, gear/flap/brake/hook/bay commands) are folded into the mirrored entity state, FMUpdatePlaneFields recomputes the derived aircraft state (weight from the current loadout via HARDPtrs, thrust from FMVector/throttle, drag and fuel burn), and the result is written back. Stores management (HARD_*) sits beside it: the loadout on each hardpoint sets the weight FMGetWeight sums, and rearm/repair rebuild the loadout between sorties.

Functions

Representative subset; the full record is in db/symbols/flight-model.csv.

VA	Symbol	Role
0x4518A0	FMInitPlane	initialise the flight model for a spawned aircraft
0x452140	FMUpdatePlaneFields	per-frame recompute of derived aircraft state
0x4516B0	FMGetWeight	sum airframe + fuel + loadout weight
0x451A60	LimitThrottle	clamp throttle to the flight-envelope / damage limits
0x451B00	SetThrottle	apply a throttle command
0x451B60	FMFlaps	flap deployment state and effect
0x451C90	FMGear	landing-gear deployment
0x451C30	FMHook	arrestor-hook state (carrier ops)
0x451D70	FMBrakes	wheel/speed-brake state
0x451E00	FMVector	thrust-vectoring nozzle angle
0x4515E0	FMUpdateWingSweep	variable-geometry wing sweep update
0x452630	FMBay	weapon-bay door state
0x451E50	FMFuelConsumption	fuel-flow rate from throttle/engine state
0x451E80	BurnFuel	drain fuel from the tanks/stores each tick
0x452770	HARDPtrs	resolve a hardpoint's loaded store record
0x452980	HARDCanLoad	test whether a store may load on a hardpoint
0x452C20	HARDLoad	load a store onto a hardpoint
0x452D90	HARDBestSeekers	rank a target's seeker-capable weapons
0x453220	HARDUnrotatedHardPos	hardpoint position in the airframe frame
0x453890	HARDStoreName	resolve a loaded store's resource-name string
0x453A70	HARDTotalFuel	total fuel including external tanks
0x453B90	HARDRearmTest	can this loadout be rearmed at the current base
0x454140	ChangePlaneType	swap the aircraft to a different type record
0x4543C0	SelectRepairPlane	pick/repair an aircraft in the campaign rearm flow

Open Questions

1. Fuel-flow scaling constant — resolved

FMFuelConsumption (0x451E50) is a two-branch scale of the throttle term:

int FMFuelConsumption(int throttle) {
    if (100 < throttle) return DAT_0050D3CB << 8;          // afterburner: fixed rate
    return (DAT_0050D3C9 * throttle * 0x100) / 100;         // mil power: linear per-percent rate
}

Both DAT_0050D3C9 and DAT_0050D3CB fall inside the _cgt type-record mirror (≈0x50D268–0x50D420; _cgt+0x161 and +0x163), which GetCurObj refreshes from the active object's type record each frame. So the fuel rate is derived from the engine/type record (_cgt), per-aircraft-type — not a single global tuning constant: _cgt+0x161 is the mil-power fuel rate (scaled linearly by throttle 0–100%) and _cgt+0x163 the fixed afterburner rate (throttle > 100%). BurnFuel (0x451E80) then drains the result.

Status: resolved — re-static.

Related

• reconstruction.md — the program this subsystem belongs to.
• objects.md — the entity service loop that drives the per-frame FM update and owns the _cg/_cgt mirror the FM state lives in.
• formats/PT.md — the aircraft performance-type record whose fields feed the flight model.
• shape-selection.md — PLANEBreakUp and the destroyed-model swap that the damage path triggers.