Triggering failures

I am currently adding random failures in the sim based on real world data, surprisingly that is the easy part, failures are working correctly in the sim using the A350. What I am finding is that I also have to trigger the correct ECAM/ FWC warning. Not a huge issue, but it adds extra time. Any experienced modders that have tried this before? Shouldn't the logic already be in the sim? if APU Gen fails, surely the APU Gen msg should appear by default?

Both fascinating and frustrating trying to create mods for FS4, its a bit sad that the modding community is so tiny compared to the other sims.

One more question - I have successfully built several random failures that work, downsteam FWC logic also works now. Before I waste any time, is it possible to use coordinates as a trigger? I can fail the GPS system. I wanted to simulate passing over certain parts of Europe, for example, by blocking or spoofing the GPS signal when near Ukraine during a flight from Doha to a European destination. Currently, I am using altitude, airspeed or time off ground as triggers for airborne failures.

$Failures = @(
# CLEAN
@{ Name = "NORMAL"; File = "system_clean.tmd"; Weight = 80 }

# SINGLE FAILURES
@{ Name = "APU_GEN"; File = "system_apu_only.tmd"; Weight = 4 }
@{ Name = "GEN_1A"; File = "system_gen1a_fail.tmd"; Weight = 4 }
@{ Name = "AIR_GEN1A_FAIL"; File = "system_air-Gen1a-fail.tmd"; Weight = 5 }
@{ Name = "GEN_1B"; File = "system_gen1b_fail.tmd"; Weight = 4 }
@{ Name = "GEN_2A"; File = "system_gen2a_fail.tmd"; Weight = 4 }
@{ Name = "GEN_2B"; File = "system_gen2b_fail.tmd"; Weight = 4 }

# DUAL FAILURES (RARE)
@{ Name = "GEN_1A_2A"; File = "system_gen1a_gen2a_fail.tmd"; Weight = 1 }
@{ Name = "GEN_1B_2B"; File = "system_gen1b_gen2b_fail.tmd"; Weight = 1 }

# ENGINE FAILURES RARE– AIRBORNE (ALTITUDE-BASED)

@{ Name = "ENG_FAIL_5000"; File = "system_eng_fail_5000ft.tmd"; Weight = 1 }
@{ Name = "ENG_FAIL_14000"; File = "system_eng_fail_14000ft.tmd"; Weight = 1 }
@{ Name = "ENG_FAIL_19000"; File = "system_eng_fail_19000ft.tmd"; Weight = 1 }

# HIGH-ALTITUDE (RARE)
@{ Name = "ENG_FAIL_34000"; File = "system_eng_fail_34000ft.tmd"; Weight = 1 }
@{ Name = "ENG_FAIL_37000"; File = "system_eng_fail_37000ft.tmd"; Weight = 1 }
@{ Name = "ENG_FAIL_41000"; File = "system_eng_fail_41000ft.tmd"; Weight = 1 }

# VERY RARE – V1 engine failure
@{ Name = "ENG_FAIL_V1"; File = "system_eng_fail.tmd"; Weight = 1 }
# SLATS
@{ Name = "SLAT_SYS1"; File = "system_SLAT_SYS1_FAIL.tmd"; Weight = 3 }
@{ Name = "SLAT_SYS12"; File = "system_SLAT_SYS12_FAIL.tmd"; Weight = 2 }
# RARE - FLIGHT COMPUTERS
@{ Name = "SEC1_FAIL"; File = "system_SEC1_FAIL.tmd"; Weight = 2 }
@{ Name = "SEC1_SEC2_FAIL"; File = "system_SEC1_SEC2_FAIL.tmd"; Weight = 1 }
# RARE - INS/ADR/GPS
@{ Name = "NAV_IR1"; File = "system_NAV_IR1_FAIL.tmd"; Weight = 2 }
@{ Name = "GPS_LOSS"; File = "system_GPS_LOSS.tmd"; Weight = 2 }

Quote from larrylynx

This is way above my paygrade but the sim does output both GPS plus lat and long data in the tmd file

GPS.OutputPosition and InertialReferenceSystem.OutputPosition plus InertialReferenceSystem.OutputLatitude and InertialReferenceSystem.OutputLongitude

Maybe this can help but like I said, mind blowing stuff for me

Good fun tinkering with this

What i find tricky is bypassing certain systems, for example, the aircraft has ground air logic for the packs and engine start, but the sim doesn't provide ground air, so I can't fail the APU bleed system on the ground; I would have no way to start the engines. I have to be careful not to break anything.

Not too sure why they coded the ground air, but never gave us an air cart to use it.

I changed plans and created a full failure program with a GUI and various scenarios built using powershell. Works great on my system, but unfortunately can't be released to the public as part of it backs up and replaces the main system.tmd (for testing purposes)

It has over 100 failures and combinations now built all with random weights based on the component or system that fails. For example, it could start with just a GEN1 failure, and then slowly progress into a full engine failure with fire and FWS warnings, or just a 30% thrust rollback from a birdstrike

My question to devs (or any modders), certain warnings like cargo fire triggers, just can't seem to be done outside of the main system.tmd (despite trying multiple times) in fact a lot of the more complex failure combos seem to be impossible from the user folder, am certain it is just a limit to my knowledge, I even asked AI, it too seems to think is is impossible.

Would going down the Python/ DLL route be the better option? Am happy using this current version for my personal use, but would like to share as a mod at some point in the future, so I need to stay away from the main system.tmd

Quote from ApfelFlieger

You can "update" the TMD data in the main folder via subfolders with the files graphics.tmd, parameters.tmd, and system.tmd.

Thanks for the reply. Just so I am clear, I currently have a parameters and system.tmd in the user folder, I have parts of the mod and my other mods operating fine from those files in the user folder.

I start getting crashes if I add more complex systems outside of the main system.tmd

For example, 3mins after take off or above 5000ft, left engine rolls back, and fails, engine fire warning displays that require ECM actions. This works perfectly if done inside the main system.tmd, fails if I add it outside of the main folder.

Are you saying I can create these files inside of the main folder (paste the engine block in there and modify?)

Sorry for being a bit slow, am newish to this

Ok, I decided to ask AI about this, it came back with the following, I don't trust it too much as it does come up with nonsense, I prefer to use it for planning and spotting any mistakes

(override-based, safe)

• Uses override system.tmd
• Only includes:
  • MEL-known items
  • pre-dispatch degradations
  • things that can exist at load time
• No random logic
• No timers
• No latches

Examples of safe override failures:

• APU GEN inop
• Single GEN inop
• TR inop
• Reverser inop
• Pack inop

These are perfect for MEL simulation.

WHAT IS SAFE TO OVERRIDE (VERY IMPORTANT)

✅ SAFE IN OVERRIDE

• Constants (<[constant]>)
• Logic gates (logic_and, logic_or)
• Availability flags
• Power source availability
• Valve positions
• Limits and clamps
• Anything that is static from flight start

❌ NOT SAFE IN OVERRIDE

• Integrators
• Timers
• Confirm delays
• Altitude-based triggers
• Random logic
• Fire bell logic
• Anything that expects sequencing

Rule:

Quote

If it needs time or state → variant
If it’s a fixed condition → override

Excellent info

My experience with AI in this scenario is great for dumping huge amounts of data (FCOM/FCTM) and sorting through it all to plan the various failures. Also great for eliminating other tedious tasks, for anything else, not worth the frustration, the actual scripting and tmd editing is not complicated. Keeping on top of everything else is the tricky part, so it makes a great planning tool.

Overall, it gives me a huge amount of respect for the people creating these TMD files from scratch.

Quote from larrylynx

So if its possible to do this sort of thing how come IPACS has not implemented it yet. Me thinks its all to do with mobile users, would want to upset the little darlings.

I agree with my TMD god Michael, option 1 is the best way to go. AI seems pretty useless and just gives you the obvious things you already know. It is also very happy to please you to the point of telling porkies....lies to those who don't know Cockney Rhyming slang.

Steve

I think a lot has to do with priorities. The PC user base seems to be tiny, how many actually care about simulating LOFT training, or having realistic failures in the SIM. This is more Fenix PMDG territory.

I'd rather they focus on rain effects, wet/dry braking. Real-world weather injection, winds aloft, Direct-TO/Missed approach procedures in the sim etc etc. Us modders can focus on the really niche stuff

After spending a few days rebuilding my PC, I am now converting all the aircaft failures to the parameters and user system.tmd folder. (full list of current failures below. This really adds a great dynamic to the sim, on departure from Antaliya, in heavy fog, I had a number Engine2 fire and rollback while climbing through 5000ft, since all the FWC logic is built in by default, it felt very immersive running through the ECAM actions.

I also noticed as long as you follow the single-engine procedure of 10 degrees or less pitch for a failure after V1, the aircraft will happily climb (perhaps not a MTOW)

Full list of faults below. I need some clarification on a few things -

A. No direct law? I had thought it was hidden, but the A350 remains in Normal Law no matter what; that means when simulating pitot or triple air data failures, the aircraft becomes hard to control. It should revert to Alternate law & Direct Law when gear is down

B. I was aware the hydraulic system wasn't finished due to lack of time for release, but the whole system looks like a placeholder. I cant see anywhere to properly fail the Green or Yellow system the A350 just ignores it.

• Most flights are normal
• Some depart with MEL-style defects
• Rare events simulate serious airborne failures
• No “mid-air random explosions” unless deliberately designed

The system supports:

• Weighted probabilities (common vs rare failures)
• Airborne-only failures using IRS altitude
• System-specific degradation (ELEC, HYD, AIR, ENG, etc.)
• Fully deterministic, repeatable behaviour
• A simple GUI front-end (compiled EXE) for one-click dispatch

Implemented Failures (Current Set)

Normal Dispatch

• NORMAL – Clean aircraft (no failures)

Electrical / Power Generation

• APU_GEN – APU generator failure
• AIR_APU_GEN_FAIL – APU generator failure with air system interaction
• GEN_1A – Generator 1A failure
• GEN_1B – Generator 1B failure
• GEN_2A – Generator 2A failure
• GEN_2B – Generator 2B failure
• AIR_GEN1A_FAIL – GEN 1A with air system implications
• AIR_GEN1B_FAIL – GEN 1B with air system implications
• AIR_GEN2A_FAIL – GEN 2A with air system implications
• AIR_GEN2B_FAIL – GEN 2B with air system implications
• GEN_1A_2A – Dual generator failure (rare)
• GEN_1B_2B – Dual generator failure (rare)

Transformer Rectifiers

• AIR_TR1_FAIL – TR1 failure (air/electrical interaction)
• AIR_TR2_FAIL – TR2 failure (air/electrical interaction)

Hydraulic Systems (Currently in testing)

• HYD_GREEN – Green hydraulic system failure (airborne, CTD-safe, LOW-pressure logic)

Pneumatic / Pressurisation

• CABIN_PRESS_LOSS – Cabin altitude / pressurisation failure
• CRUISE_EM_DESCENT – Emergency descent profile
• CRUISE_EMDECENT_SLOW – Slower emergency descent variant

Fluids, Oils & Leaks

• APU_OIL_FAIL – APU oil failure
• ENG1_OIL_SLOW_LEAK – Engine 1 slow oil leak
• APU_FUEL_1 – APU fuel pressure issue
• OIL_QTY_1 → OIL_QTY_5 – Progressive engine oil quantity scenarios

Reversers

• REV1 – Thrust reverser 1 inoperative
• REV2 – Thrust reverser 2 inoperative

Engine Failures (Airborne / Altitude-based)

• ENG1_PREV1_FAIL – Engine 1 failure prior to V1
• ENG_FAIL_V1 – V1 engine failure
• ENG2_FAIL – Engine 2 failure

Fire & shutdown triggerd at specific altitudes:

• 500 ft
• 2000 ft
• 5000 ft
• 5500 ft
• 14,000 ft
• 19,000 ft
• 34,000 ft
• 37,000 ft
• 41,000 ft
• 41,500 ft

Includes both engine failures and engine fires on either side.

Batteries & AC Buses

• BAT_1_FAIL_AIRBORNE – Battery 1 failure
• BAT_EMER_2_FAIL – Emergency battery 2 failure
• BAT_EMER_2_DC_FAIL – DC side failure
• BAT_EMER_2_AC_FAIL – AC side failure
• ACBUS1_AIR_FAIL – AC Bus 1 failure (airborne)

Air Data & Navigation

• PITOT_CAPT_ONLY – Captain pitot failure
• NAV_IR1 – IR1 failure
• GPS_LOSS – GPS signal loss

Flight Controls

• SLAT_SYS1 – Slat system 1 failure
• SLAT_SYS12 – Dual slat system failure

Flight Computers

• SEC1_FAIL – SEC 1 failure
• SEC1_SEC2_FAIL – Dual SEC failure (rare)

)

• No random mid-flight script injections
• Full system realism without CTDs

Quote from Jet-Pack (IPACS)

Yes, some things like hydraulics are not implemented and therefor failures of that system have no consequences yet.

The alternate and direct law are also not yet implemented for the A350 and A380 but are available on the A320 series.

Ok, thanks. The 'not yet' part gives me hope for the future.