Aircraft troubleshooting that walks the technician to the cause, cites every step, and gets the aircraft out on time
Each fault traced to its cause with cited steps, and the aircraft out on time.
See one case, screen by screen ↓Aircraft Troubleshooting Assistant is AI aircraft troubleshooting software for line maintenance: technicians ask about a fault and get the fix path, cited to the troubleshooting manual and the fleet's own history. Seven aircraft maintenance AI agents read the write-up and fault data, cite the manual task for this tail, find the fixes that held, guide fault isolation step by step and draft the logbook entry. The technician decides every action and signs.
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Aircraft troubleshooting starts when a pilot writes up a fault, and the line technician has until the next departure to find the cause, fix it and sign the logbook. That means finding the right task in the troubleshooting manual for this tail's effectivity and the current revision, phoning Maintenance Control, asking whoever saw the same message last month, and checking stores, tooling and the required inspection list before a panel comes off.
When the clock runs short, too many faults are closed with a reset and an ops check — and that is how repeat defects are born. The fix that worked last time sits in a free-text corrective action at another station, repeats surface weeks later in the reliability report, and an isolation night shift started loses its findings at shift change.
Estimated split of one line fault, by hand and with the solution; the totals match the working solution's median before and after (3.9 h and 2.3 h).
Seven agents read the fault, cite the manual and the fleet's own fixes, and walk the technician through isolation; the technician decides and signs.
Corvane Airways 737-8 N812CV lands at Denver late on Oct 14 with a BLEED DUCT LEAK L message written up in climb. It is due out at 08:55 as CV1422 to San Francisco. Here is the aircraft troubleshooting, screen by screen, in the working solution.
Luis works the DEN line on day shift. Today shows his two open faults, one DEN departure at risk and two repeat faults at the station, and what the agents did overnight: the write-up read, the repeat flagged, causes ranked for 9 open faults across 5 stations, a hand-off drafted. His first job is at the top, with 2 h 43 m to departure.
Isolation agent: “Your first job is N812CV at B31: a repeat BLEED DUCT LEAK L, due out at 08:55. Dale's leak detection test passed overnight, so the clamp leads at 61%. Step 2 is yours: the clamps at the precooler.”
The fault reader took maintenance message 36-11021 from the aircraft by datalink and read the captain's write-up under 14 CFR 121.563, logbook page 4471, item 1: zone 431, the left engine strut, lit on the aircraft outline. The manual agent cites troubleshooting manual task 36-11-00-810-801, revision 58, effective for N812CV's line number 7,236. The fleet history agent finds twelve earlier reports on Corvane 737-8s and the three most like this one: N827CV's clamp replacement held 220 days, N841CV's re-torque came back in 11 days, N806CV's sensing element replacement held.
Every agent message carries numbered citations to the manual passage, the fleet record or the reading.
The same message was closed at SFO on Oct 6 with a passing leak detection test and a reset: no fault found. Two reports in nine days meets Corvane's repeat rule, so the repeat watch agent pages Maintenance Control and blocks a reset-only close. Choosing “Reset and close” opens a refusal, not a sign-off.
“Corvane's program says a repeat may not be closed by a reset or a test alone. The last reset, on Oct 6, is why it came back.”
Dale ran step 1 at 01:22: the leak detection system test passed, loop resistance normal on both channels. The isolation agent re-ranked the causes — clamp 61%, seal 21%, sensing element 11%, wiring 7%. Out of time with the lift booked for 06:00, Dale handed off; the logbook writer drafted the turnover at 05:28 and Luis accepted it at 06:04.
The turnover: Done · Found · Next — each line cited to the conversation.
With panels 431AL and 431BL open, the isolation agent asks Luis what he found at the V-band clamps. He taps one answer. The clamp moves to 92% and the agent says why: hot air escaping at a loose joint is what the loop detected, and the loop itself tested good overnight. Fleet history says replace, don't re-torque — both re-torques on record came back within 14 days.
The isolation agent never tells the technician to skip a manual step; below 0.70 confidence it asks or brings in an engineer.
Working on its own, without seeing the isolation agent's answer, the check agent confirms task 36-11-05-400-801 applies and revision 58 is current, clamp P/N 3618-0425-02 is in DEN stores (2 in bin D-14), torque is 85–95 in-lb with wrench TW-0412 in calibration to Jan 12, 2027, it is not a required inspection item, and 1.6 hours fits before CV1422. Luis approves the plan, edits it or rejects it — here, he approves.
“I checked the plan — replace the precooler inlet clamp, then leak check — on my own, against the records.”
Luis asks for the clamp in the conversation; Mike Sato delivers it to B31 at 06:52, batch 26-0911, with its certificate of conformity. Luis records his readings: clamp replaced, torque 92 in-lb, blanket serviceable, leak check at idle for 5 minutes with no leak and no message. Both readings are inside the manual's limits, and the isolation agent marks the fault isolated and corrected.
Isolation agent: “Fault isolated and corrected: the loose precooler inlet clamp was the cause.”
The logbook writer drafts the entry from the conversation: the discrepancy as the captain wrote it, the troubleshooting manual task and revision, Dale's test with his certificate number, the finding, the clamp replaced with its part number, batch, torque and wrench, the blanket inspection, the leak check, and the repeat it closes. A record check beside it ticks the description, date and performer under 14 CFR 43.9(a), the repeat rule and part traceability; the signature line and 121.709(b) wait for Luis.
The logbook writer never signs and never returns an aircraft to service.
Luis reviews the entry, picks reason code RS1 — fault corrected, return to service — and signs with his A&P certificate 4120917. N812CV is returned to service at 08:10, 2.1 hours after he accepted the hand-off, and CV1422 leaves on time. The evidence pack for an inspector — the write-up, the conversation, the sources cited, the plan check, the readings, part traceability, the signed entry and the audit trail — downloads as one 14-page PDF.
“Your signature certifies the work in this entry under the Corvane maintenance manual and that no known condition makes the airplane unairworthy.”
From the two re-torques that came back, the fleet history agent drafts fleet tip FT-36-004: on a 737-8 precooler inlet clamp found loose after a leak message, replace it, don't re-torque. It waits for Hannah Brooks with its evidence — re-torques came back 2 of 2 times, clamp replacements held 4 of 4. No agent cites a tip until an engineer approves it.
Draft · not cited yet.
The same repeat fault, seen by the five people who carry it — what their shift looked like, and what it looks like now.
Seven agents read the fault, cite the manual and the fleet's own fixes, and walk the technician through isolation; the technician decides and signs.
Reads the logbook write-up and the maintenance messages the aircraft sends by datalink, and finds the message, ATA chapter, zone and phase of flight.
Searches the troubleshooting manual (TSM; the fault isolation manual, or FIM, on some fleets) for the task that fits this tail's effectivity and the current revision, and cites its steps, cautions and the maintenance manual tasks it points to.
Finds how the airline fixed the same message before and whether each fix held, and drafts fleet tips from the outcomes.
Ranks the likely causes, walks the technician through fault isolation one step at a time, asks what they found and re-ranks with the reason for every move.
Independently checks the plan — effectivity, revision, the part in stores, tooling calibration, required inspection items, the MEL and the time to departure — and blocks a plan that does not fit. It also runs the record check on the drafted logbook entry against 14 CFR 43.9(a) and 121.709(b).
Applies the reliability program's rules — repeat is two reports in 10 days, chronic is three in 15 — refuses a reset-only close on a repeat, alerts Maintenance Control and the station lead, and opens an engineering review for a chronic fault.
Drafts the corrective action for the electronic logbook entry, and the shift turnover, from the conversation, each line cited to the step, the reading or the manual task.
Decides every action and signs; Maintenance Control decides deferrals; engineers approve fleet tips. The agents propose; a named person decides.
Generative AI in aircraft maintenance only helps when the answer can be checked. Technicians, leads and controllers ask the way they would ask a colleague; every answer points to the manual passage, the fleet record or the reading it came from, and nothing is signed, ordered or deferred until a person says so.
Why is the clamp the likely cause on N812CV?
Three things moved it to 92%. Dale's leak detection test passed, so the sensing element fell from 31% to 11%. Luis then found the precooler inlet clamp loose with heat marks. And 6 of Corvane's 12 earlier reports of this message were clamps.
What fixed BLEED DUCT LEAK for good on the 737-8?
Clamp replacements held 4 of 4 times; re-torques came back 2 of 2 times; sensing element replacements held twice.
Is N812CV going to make 08:55?
If step 2 finds the clamp, yes: replacement and leak check take about 1.6 hours and the part is in DEN stores.
Show the repeat faults open right now
Three: N812CV (2 in 9 days), N845CV (chronic, 3 in 14) and N819CV (2 in 8). None can be closed with a reset alone.
13 screens from the working solution, on its sample data. Pick one to see it large.
The rules the agents follow are settings your Director of Quality approves. A proposed change waits for that approval, and the agents keep the current value until then.
| Setting | Default | Choose from |
|---|---|---|
| Repeat fault | Same fault twice on one aircraft within 10 days | Any window in days · Director of Quality approves |
| Chronic fault | 3 reports within 15 days → engineering review | Any window in days · Director of Quality approves |
| No reset-only close on a repeat | On — a controller may override with reason O1 | On · Off |
| Confidence floor | 0.70 — below it the isolation agent asks or escalates | Any value · Director of Quality approves |
| Departure alert | 60 minutes before departure if not isolated | Any number of minutes · Director of Quality approves |
| Fix counts as held after | 30 days without a repeat | Any number of days · Director of Quality approves |
| Who signs the logbook | Aircraft maintenance technicians and lead technicians | By role, with certificate numbers from training records |
Every figure is labelled: a target the solution is built to, an estimate, a typical published result, or a proven one.
“demo” = seen in the working solution, on its sample airline data · “target” = the design goal, measured in the live solution · “estimated” = our estimate (the split of a fault's ground hours) · “typical” = published figures (McKinsey, The generative AI opportunity in airline maintenance — about 60% of technician time on research, troubleshooting and reports; AIN, Oct 10, 2025 — 182 of 248 windshield-heat work orders at one FAA repair station in 2024 were repeats). Regulations named as context: 14 CFR 43.9(a), 121.563 and 121.709. People, airlines, aircraft registrations, flights, work orders and part numbers named on this page are fictional — characters and sample data in the working solution.
Aircraft Troubleshooting Assistant is AI aircraft troubleshooting software for line maintenance: technicians ask about a fault and get the fix path, cited to the troubleshooting manual and the fleet's own history. Seven aircraft maintenance AI agents read the write-up and fault data, cite the manual task for this tail, find the fixes that held, guide fault isolation step by step and draft the logbook entry. The technician decides every action and signs.
It is AI for aircraft maintenance technicians, not instead of them. The isolation agent ranks the likely causes from the troubleshooting manual and the airline's fix history, then asks the technician what they found after each step and re-ranks with the reason. In the working solution a passing leak detection test drops the sensing element to 11%, and “clamp loose, heat marks on the blanket” lifts the clamp to 92%.
Yes. Troubleshooting manual search is by tail: the manual agent cites the fault isolation task for the aircraft's effectivity and the revision in force — revisions load the day they publish — and never cites a superseded page. The check agent confirms effectivity and revision again before the plan is approved.
The repeat watch agent applies your reliability program's rules for repeat (repetitive) and chronic defects, such as two reports in 10 days for a repeat and three in 15 for a chronic fault. It refuses to close a repeat with a reset or a passing test alone (a “no fault found”), alerts Maintenance Control and the station lead, and flags chronic faults to Technical Services for an engineering review. Only a controller can override, with a reason code.
It drafts it. The logbook writer turns the conversation into a corrective action with every line cited to the step, the reading or the manual task, and the check agent checks the draft against the elements of 14 CFR 43.9(a) and 121.709(b). The technician can edit any line, then signs with their certificate; no agent signs.
The logbook writer drafts a turnover for every open isolation — what was done, what was found and what is next, with the readings — and the next shift accepts it or asks back. A technician can also hand off their own open conversation in one click.
Yes. The agents never sign, return an aircraft to service, order a part, defer an item, close a repeat with a reset or cite a superseded manual. The technician approves every plan and signs every entry, the maintenance controller decides deferrals and overrides, engineers approve fleet tips, and the Director of Quality approves the rules.
The Agentic Solution Engine builds and deploys it from your requirements and documents — your manuals, MEL, reliability program and a sample of past write-ups and work orders — and it goes live once every quality gate has passed. We will walk you through it on your own faults first.
No tail flies past an AD, and every line of the status report is proven.
1-min demoService Bulletin EvaluationEvery bulletin decided in days on the fleet’s own evidence, every tail and dollar cited.
1-min demoDeferred Defect ManagementNo aircraft flies past its MEL limit, and every fix lands on a planned overnight.
1-min demoWe'll run Aircraft Troubleshooting Assistant on a sample of your own past write-ups, manuals and fleet history.