Kids Remote Control Airplane

Rationale: Bench test eliminates airframe variables. Optical tachometer gives ±50 RPM accuracy — sufficient for 80% RPM threshold measurement. 5 trials cover unit-to-unit variation.

Rationale: EN 71 Part 1 Clause 8.6 propeller impact method. Rigid cylinder simulates worst-case rigid obstacle contact geometry. Ballistic pendulum is the standard fragment energy measurement method per EN 71 test protocol.

Rationale: SIL 2 safe state test must be deterministic. Variable bench supply simulates battery voltage drop under load without battery risk during test. Tight cutoff tolerance (±0.1V) ensures neither premature flight termination nor deep discharge. Results must be documented in safety case.

Rationale: Integration test for ESC-motor interface. Oscilloscope measurement of dead time directly proves shoot-through prevention — the primary failure mode causing ESC destruction and motor runaway.

Rationale: Prop retention failure at flight speed is a SIL 2 hazard. Static load test at 2x normal operating load provides confidence margin against dynamic in-flight loads and vibration-induced loosening.

Rationale: This is the control latency bench test referenced as STK-001 in previous session context. Logic analyser measurement captures both MCU processing delay and RF packet timing. 10-sample statistical method accounts for FHSS hopping timing jitter.

Rationale: Range test is the system-level integration test for the RF link. Three orientations cover antenna radiation pattern asymmetry. 60-second run at 50Hz gives 3000 frame opportunity sample — statistically robust for <1% threshold detection (±0.2% confidence interval).

Rationale: System-level integration test covering the complete TX-to-actuator signal chain. Tests two paths simultaneously: the digital control path (TX MCU -> RF -> FCE -> servo) and the power path (ESC -> motor). Provides single test evidence for SYS-REQ-002 end-to-end latency and SYS-REQ-001 motor performance under realistic radio range conditions.

Rationale: Load cell bench test isolates motor thrust from airframe and battery sag variables. 30-second test at full throttle confirms rated thrust at nominal voltage. Result directly validates the 80g minimum thrust specification without requiring flight-test infrastructure.

Rationale: 75 percent throttle for 10 minutes represents sustained cruise load without the intermittent duty reduction from bank angles and throttle modulation in flight. Still-air condition removes forced convection benefit, creating a worst-case thermal scenario. Contact or IR measurement at 30s intervals ensures peak temperature is captured before the measurement decays.

Rationale: Mass budget compliance is most directly verified by weighing the actual subsystem assembly. 0.1g scale resolution is adequate for a 45g limit with 5% budget margin typical for component assemblies.

Rationale: Failsafe configuration is safety-critical per SYS-REQ-004; functional testing is the only way to verify the specific failsafe values are stored and output correctly. The 600ms timeout window accounts for receiver frame-loss debounce timing.

Rationale: Power delivery interface must be verified under actual load conditions; static voltage measurement is insufficient. 50 percent throttle represents a realistic sustained cruise load. 6.0V minimum threshold at the ESC input prevents voltage sag below the minimum required for reliable commutation.

Rationale: Reverse-polarity connection destroys the ESC and may cause battery fire; this is a safety-critical failure mode that must be prevented by physical design, not procedure. Visual inspection and physical mating test confirm polarisation protection without requiring powered test.

Rationale: Safety-critical LVC test verifies that the protective mechanism activates before permanent cell damage occurs. 0.1V/s ramp rate represents realistic in-flight discharge under moderate load.

Rationale: Bench discharge test at representative cruise current measures actual capacity independent of ESC efficiency. 9.6min provides 20% margin over the 8-minute STK requirement to account for in-flight efficiency losses.

Rationale: Safety-critical test for SIL-2 requirement. Three repetitions confirm the charger IC does not exhibit false-positive termination or overshooting the 4.21V limit on repeated cycles.

Rationale: Failsafe timing test is safety-critical (SIL-1); five repetitions cover statistical variation in transmitter shutdown timing. Oscilloscope measurement eliminates observer reaction time error from manual stopwatch method.

Rationale: Gimbal test allows bank angle measurement without actual flight risk. 47-degree pass criterion (vs 45-degree requirement) provides 2-degree instrument tolerance. Recovery time test confirms stability augmentation is active rather than just limiting.

Rationale: Drop test from 5.1m achieves 10 m/s impact per SYS-REQ-008 under gravity (v^2 = 2*g*h; h = v^2/2g = 100/19.6 = 5.1m). Grass surface matches specified impact medium. Three units provide sample coverage for manufacturing variation in foam density and latch torque.

Rationale: Direct calliper measurement of control surface deflection at full servo travel confirms the pushrod geometry and surface hinge position achieve the required authority.

Rationale: IFC-REQ-004 mandates 50 Hz frame rate and 20ms latency across the RF control link — the primary human-in-the-loop constraint. Direct measurement at the receiver PWM output is the only way to verify end-to-end latency inclusive of FHSS packet scheduling, receiver decode, and PWM generation.

Rationale: IFC-REQ-006 defines the throttle signal specification and 200ms motor-stop response critical to failsafe operation — the ESC must cut motor power within 200ms of FCE receiving a failsafe command, which traces to SYS-REQ-004 (500ms total failsafe time budget).

Rationale: SUB-REQ-011 governs the 5V power rail supplying the FCE receiver, MCU, and servos. Voltage outside 4.75–5.25 V causes servo malfunction; slow transient recovery causes glitches during motor throttle changes that generate BEC switching noise spikes.

Rationale: SUB-REQ-014 is the primary over-current protection for the 2S LiPo wiring harness. A fuse that fails to trip at 8 A within 1 second will allow sustained short-circuit current that risks wiring insulation fire — directly mitigating H-002 (LiPo thermal runaway).

Rationale: SUB-REQ-016 defines the maximum acceptable charge time from fully depleted — 90 minutes at 0.5C is the safety-limited maximum charge rate for LiPo cells in consumer products per IEC 62133-2.

Rationale: SUB-REQ-017 ensures the parent can verify charging status without approaching the charging area — a safety practice for LiPo monitoring that reduces risk of unattended fire (H-002).

Rationale: SUB-REQ-020 governs servo response speed; servos slower than 100ms per full deflection cause sluggish control response that makes trimming difficult for novice pilots and may cause oscillations in gusty conditions.

Rationale: SUB-REQ-021 enforces the FCE mass allocation within the 250 g total system budget (SYS-REQ-001). Inspection alone insufficient — each component's mass may individually comply while exceeding the subsystem budget when assembled.

Rationale: IFC-REQ-012 defines the BEC output to FCE supply quality; ripple exceeding 50mV can corrupt SPI communications from IMU to FCE MCU and cause servo position jitter — both compromise flight stability.

Rationale: IFC-REQ-018 defines the gyro data path that feeds the stability augmentation loop; sample rate below 1 kHz causes aliasing in the 250 Hz control loop, and noise density above the limit causes oscillation in the stabiliser output at low airspeed.

Rationale: SUB-REQ-023 enforces the airframe mass allocation within the 250g total system budget. The airframe is the largest variable-mass component; exceeding 80g directly reduces the available budget for electronics and battery, forcing compromise on performance or safety.

Rationale: STK-REQ-001 is a stakeholder-level scenario requirement that can only be verified by direct demonstration with target users. Analysis and inspection cannot confirm that a real child can complete the workflow — only a live trial can. 5 participants gives statistical confidence that the requirement is met across the age range, not just for one child.

Rationale: STK-REQ-002 requires demonstration that a real novice can execute manoeuvres — this cannot be verified by analysis of control response data alone. The requirement is about pilot experience, not control surface performance, so a user trial is the only valid method. Piggybacking on the VER-REQ-036 trial avoids duplicate test overhead while maintaining separation of acceptance criteria.

Rationale: Direct physical measurement of the mass budget compliance is the only reliable method — dimensional analysis cannot account for manufacturing variation in foam density, adhesive application, or component selection from approved alternatives.

Rationale: Labelling compliance is a binary pass/fail inspection requirement. Pre-production sample inspection catches tooling/artwork errors before production commitment. Regulatory non-compliance cannot be corrected post-production without a product recall.

Rationale: SUB-REQ-025 requires ESC to respond to PWM loss within 150ms and restore full output within 500ms. Replaces vague 'normal operation' with quantified RPM recovery: plus-or-minus 200 RPM tolerance is derived from 3 percent speed regulation spec at hover throttle. Without a measurable recovery criterion, a pass would not demonstrate restoration of controlled flight thrust.

Rationale: Gimbal test allows quantitative measurement of angle limiting performance in a controlled ground environment, capturing the same flight dynamics as airborne test without crash risk. 500ms recovery window is conservative relative to the 250Hz loop rate capability.

Rationale: Bench test with radio link simulation is the only controlled method to measure 500ms timeout compliance. Flight test would require deliberate signal loss in a live flight environment which is hazardous and unrepeatable.

Rationale: Drop test from 0.5m onto hard surface approximates a 10 m/s nose-first impact deceleration load for a 250g aircraft. This is the minimum test for battery retention compliance before certification to EN 71 Part 1. Physical inspection is required because analytical methods cannot predict connector pull-out under shock loading without FEA.

Rationale: Direct measurement on load-cell stand is the only method that can verify a specific thrust value. A 20% thrust shortfall results in insufficient climb rate for safe recovery.

Rationale: Mass measurement is the only valid verification. Wiring harness mass varies by assembly. A propulsion assembly >45 g pushes total aircraft mass above the 250 g SYS-REQ-011 budget.

Rationale: Thermal limits must be tested in situ because airflow in a foam fuselage differs substantially from open-air bench tests. ESC overtemperature >85 degrees C degrades MOSFET switching and risks PCB delamination.

Rationale: Failsafe bind configuration cannot be verified by inspection alone — end-to-end signal interruption with channel measurement is required. An incorrectly stored failsafe (throttle at 50%) would result in a runaway aircraft, which is hazard H-001.

Rationale: Run-time verification under representative load is required. Manufacturer capacity ratings are at low C rates; actual 10C discharge capacity can be 10-20% lower. An 8-minute flight time is the minimum safe window for a child to complete a flight circuit without mid-air power loss.

Rationale: Mass measurement is the only valid verification for a physical part. A LiPo >30 g consumes more than 12% of the 250 g SYS-REQ-011 mass budget for a single component, leaving insufficient margin for other subsystems.

Rationale: Low-voltage cutoff timing is safety-critical. A delay >200ms allows cell voltage to continue falling toward catastrophic 2.5V deep-discharge threshold. Deep discharge of a LiPo below 3.0V/cell causes permanent electrode damage and increases fire risk (hazard H-002).

Rationale: Overcharge termination accuracy is safety-critical. Failure to terminate at 4.20V leads to LiPo thermal runaway. Testing with external cell voltage logging provides independent verification. A 10 mV overcharge tolerance is the accepted industry margin per IEC 62368-1.

Rationale: Receiver failsafe timing is the primary flight safety mitigation for signal loss events (hazard H-001). A 500 ms timeout is derived from maximum safe glide distance: at 10 m/s, 500 ms = 5 m travel. Direct PWM output probing excludes servo mechanical latency from the measurement.

Rationale: Stability augmentation must be tested under dynamic inputs because static analysis cannot capture closed-loop behaviour. The +-45 degree limit prevents tip-stall in trainer mode for novice pilots; the 50 ms loop rate is the minimum for effective proportional correction of typical roll rates for this aircraft size.

Rationale: Battery ejection on impact (hazard H-002) must be tested as a physical crash simulation because structural analysis of foam cannot predict latch retention under dynamic loading. The 10 m/s velocity represents a realistic unrecoverable nose-dive from typical training altitude.

Rationale: Control surface travel directly determines pitch and yaw authority. Insufficient travel (<10 mm) prevents the aircraft from achieving the turn and pitch rates required for SYS-REQ-002. Measurement must be done in as-built configuration as linkage geometry can reduce theoretical travel by 15-30%.

Rationale: Setup time and ease-of-use cannot be verified by inspection of the quick-start guide. Direct user testing with the target demographic is required because cognitive load for children differs significantly from adult engineers. Failure to meet 10-minute setup removes the core product differentiator from STK-REQ-001.

Rationale: USB input protection must be tested for reversal and overcurrent because children may connect incorrect cables or chargers. A field failure where a reversed cable damages the charger creates a replacement cost and potential fire risk from unprotected lithium charging circuits.

Rationale: Aerodynamic performance cannot be verified by analysis without CFD. A lift-to-drag ratio below 4:1 results in insufficient glide and excessive power consumption, reducing flight time below the 8-minute target and increasing crash risk from energy depletion.

Rationale: RF compliance with FCC Part 15.249 is verified by manufacturer certification — individual product testing is cost-prohibitive and not required where the RF module is a certified sub-assembly. FHSS channel count is verified by spectrum observation to confirm the module behaves as declared.

Rationale: Voltage drop at the power interface directly affects motor performance. A drop >0.2V at 8A represents a 2.7% efficiency loss and may cause under-voltage motor stumble. 18 AWG wire ampacity verification prevents insulation overheating under sustained high-current draw.

Rationale: Gate driver propagation latency >150 ns introduces timing error into BEMF zero-crossing detection, causing commutation mis-timing at high motor speeds. At 6000 RPM (100 Hz electrical), 150 ns represents 1.5 degrees of timing error — within acceptable tolerance for smooth commutation.

Rationale: Antenna VSWR >2.0:1 results in >11% reflected power, reducing effective TX power and range below the 150 m SYS-REQ-007 requirement. VNA measurement is the standard characterisation method for RF interface impedance matching.

Rationale: PWM timing accuracy directly determines servo positioning accuracy and control surface deflection. A +-50 us timing error at 50 Hz corresponds to +-2.5 degrees of elevator deflection error, which affects pitch stability. Logic level compatibility ensures reliable servo trigger.

Rationale: Rudder PWM accuracy determines yaw control authority. Derived from same rationale as IFC-REQ-011 elevator interface — a +-50 us timing error corresponds to +-2.5 degrees of rudder deflection error, affecting turns for novice pilots.

Rationale: Balance tap connector pin-out determines whether the charger monitors individual cells correctly. An incorrect wiring sequence causes the charger to read incorrect cell voltages and may overcharge one cell while undercharging another, causing premature capacity degradation or cell reversal.

Rationale: FCE PCB vibration isolation is required to prevent IMU measurement corruption from motor and propeller harmonics (typically 50-200 Hz for this propulsion system). 20 dB attenuation ensures IMU noise floor remains below 0.1g, sufficient for gyro-assisted stability augmentation at SUB-REQ-019 loop rate.

Rationale: Joystick spring force outside 100-200 gf range causes control difficulties for children — too light causes unintended inputs; too heavy causes fatigue and imprecise control. Child hand ergonomics must be verified with the actual demographic, not adult testers, as hand spans differ by 30-40%.

Rationale: AC mains compatibility across global voltage ranges (100-240V) must be tested to prevent charger failure in overseas markets. Efficiency >= 90% is required to prevent excessive heat generation in the enclosed charger housing, which could create a surface temperature hazard for child contact.

Rationale: Battery voltage measurement accuracy determines when the low-voltage warning and cutoff are triggered. A +-50 mV error at the 3.3V monitoring threshold represents +-100 mV error on the actual cell voltage, which could cause premature cutoff or delayed warning — the latter contributing to deep discharge events (hazard H-002).

Rationale: Reclassified from Inspection to Test during validation session 497: the procedure includes applying 30 A from a bench supply to confirm PTC fuse rating under live current — this is a functional test, not a passive inspection. For a SIL-2 requirement, Test is the appropriate verification method. Visual inspection of XT30 markings and reverse-polarity mating attempt are also included as part of the same test procedure.

Rationale: The AC-DC module output voltage tolerance directly affects balance charger IC operating range. A ripple >100 mV peak-to-peak superimposes AC noise on the charger reference, causing cell voltage measurement error and potential premature or missed termination. 100 mV ripple limit is consistent with charger IC datasheet requirements.

Rationale: Direct system-level acceptance test for the primary performance requirement. Mass measurement is pre-flight; flight envelope test confirms the airspeed range is achievable with the as-built aircraft.

Rationale: Control latency directly drives flight safety — excessive lag causes PIO (pilot-induced oscillations). 50 ms is derived from the human motor reaction threshold for novice pilots.

Rationale: Stability augmentation is the primary mechanism preventing novice pilots from entering unrecoverable attitudes. Test must confirm both the bench-level algorithm response and the in-flight physical result.

Rationale: SYS-REQ-004 specifies 500ms failsafe activation on signal loss. The amended pre-test baseline replaces vague 'confirm normal flight control response' with quantified surface deflection latency (<50ms) and throttle response (<100ms) traceable to IFC-REQ-004, establishing that the control loop was functional before the failsafe test sequence. Without this baseline, a passing failsafe test could be on an already-degraded control system.

Rationale: LiPo overcharge termination is a SIL-2 safety requirement per the hazard register. Cell overvoltage and thermal runaway are the primary LiPo fire mechanisms.

Rationale: Propeller blade contact with a child's hand at rotation speed is a primary injury hazard (severity: severe). EN 71 and ASTM F963 require demonstration that propeller does not transmit injurious forces.

Rationale: RF link reliability at operating range is the primary mechanism preventing unintended signal loss failsafe activation during normal flight. 150 m derives from STK-REQ-007 operational range.

Rationale: Crash safety is a SIL-1 requirement. Battery ejection during crash creates LiPo fire hazard; exposed wiring creates electrocution risk; sharp edges cause lacerations during post-crash handling by a child.

Rationale: First-flight readiness within 10 minutes is STK-REQ-001 — the primary out-of-box experience requirement. User trial with age-appropriate participants is the only valid verification method.

Rationale: LVC cutoff protects the LiPo from deep discharge damage and is a SIL-2 safety requirement. Audible warning is the primary pilot notification mechanism for battery state since there is no telemetry display.

Rationale: STK-REQ-003 derives from the parent supervisor role — the safety case relies on a non-expert adult being able to confirm airworthiness before flight. Failure to meet this requirement means the aircraft may be flown with a low battery, unbound link, or damaged airframe without adult awareness, directly increasing risk of uncontrolled flight (H-001).

Rationale: Updated to align thermal cutoff acceptance criterion with SYS-REQ-005 (45°C threshold). Previous criterion of <60°C was 15°C above the specified threshold and would have permitted a non-compliant charger to pass the test. Battery thermal runaway initiates above 60°C; the 45°C cutoff provides the required safety margin. Thermal pad simulation replaces the less controllable previous method.

Rationale: STK-REQ-005 is the primary bystander injury prevention requirement. At 12J, an impact is broadly equivalent to a 0.5kg mass falling 2.4m — below the threshold for serious injury per EN 71 impact analysis. Direct measurement of mass and max airspeed with KE calculation is the only valid verification method.

Rationale: STK-REQ-006 is the primary uncontrolled-flight-away safety requirement. Demonstration at altitude with range is the only way to validate real failsafe behaviour including aerodynamic response — bench test cannot replicate the flight dynamics component.

Rationale: STK-REQ-007 ensures the product remains manufacturable and repairable using off-the-shelf parts. A demonstration purchase and build proves that the design has not inadvertently specified proprietary parts that create supply chain dependence.

Rationale: STK-REQ-008 is the field repairability requirement — a key differentiator from disposable toys. The 30-minute repair criterion was derived from typical park or field session duration; longer repairs mean the flying session is lost.

Rationale: EN 71 and ASTM F963 are mandatory legal requirements for toy safety in EU and US markets. Third-party laboratory certification is required by both standards for products in these categories — self-declaration is not sufficient for CE marking or CPSC compliance.

Rationale: STK-REQ-010 is the regulatory threshold for UAS exemption from FAA Part 107 and EU UAS category A1 registration. Exceeding 249g removes the product from the registration-exempt category, creating a regulatory barrier for purchasers. Three-sample test accounts for unit-to-unit mass variation in foam moulding.

Rationale: STK-REQ-011 ensures the product is self-contained at first purchase — the buyer must not need to source additional components before the first flight. Failure here creates immediate return-to-retailer events and negative safety outcomes if a child attempts to fly with a missing charger or no spare propeller.

Rationale: STK-REQ-012 requires legible labelling per EN 71 and ASTM F963. Replaces vague 'normal retail display lighting' with the specific 500 lux ISO 3664 illuminance standard used in retail print inspection. 500 lux is the minimum recommended general retail illuminance per ISO 8995-1; using this value ensures the test represents the worst realistic viewing condition at shelf level, not an artificially bright laboratory setting.

Rationale: STK-REQ-013 is the environmental envelope requirement. The 15-knot wind limit was chosen as the threshold for typical park flying conditions. Controlled-flight demonstration at wind limit verifies structural margins, power budget, and gyro stabilisation all function together at the boundary of the operational envelope.

Rationale: STK-REQ-014 is a mandatory radio regulatory requirement in all target markets. FCC type approval and CE RED Declaration of Conformity are required before sale. EIRP and FHSS requirements derive from spectrum access conditions for the 2.4 GHz ISM band in both US and EU regulations.

Rationale: SYS-REQ-013 requires post-crash documentation and kit contents — both must be verified by inspection (documentation content) and demonstration (user behaviour). Behaviour observation is required because a printed instruction that users do not follow provides no safety benefit; the demonstration confirms the instruction is clear enough to be followed without coaching. Three-parent sample provides statistical confidence across non-RC-experienced users.

Rationale: STK-REQ-001 requires a 25-minute park session including setup and teardown, achievable by a child aged 8-14. Direct usability observation with a representative user is the only method that validates the setup complexity claim; document review and analysis cannot reveal whether a child can physically unpack, charge-check, and launch the aircraft within the time budget. Three-trial average eliminates first-flight novelty effects.

Rationale: STK-REQ-002 requires that flight controls are learnable by a novice child with no prior RC experience. Only a direct user study with representative users can validate learnability. The success criterion (2 of 3 completing turns) is consistent with introductory aviation training benchmarks and accounts for individual learning rate variation.

Rationale: STK-REQ-003 requires that a parent can verify safe operating state using only onboard visual indicators and the product manual. Usability testing with a representative non-technical adult is the only valid method. 60 seconds is the expected interaction time for pre-flight checks per the Weekend Park Flight scenario.

Rationale: STK-REQ-005 limits kinetic energy at any achievable airspeed to below 12 J to ensure injury risk from collision is below the threshold for serious blunt force injury (established in EN 71-1 impact energy limits). Direct measurement of both mass and airspeed is required because analytical estimation of maximum airspeed in uncontrolled conditions has too high an uncertainty for a safety-critical claim.

Rationale: STK-REQ-009 requires compliance with EN 71 Parts 1-3 and ASTM F963 — legal market access requirements in the EU and US respectively. Third-party accredited laboratory testing is mandatory under the EU Toy Safety Directive 2009/48/EC for products with electrical components and lithium batteries. Internal test results are not accepted as conformance evidence by market surveillance authorities.

Rationale: STK-REQ-010 requires mass below 250 g to remain exempt from UAS registration requirements under EU Regulation 2019/947 and equivalent jurisdictions. Direct measurement on multiple production samples is required because manufacturing variation can add 1-5 g across lots; testing a single sample would not represent worst-case mass distribution.

Rationale: STK-REQ-011 requires the complete system packaged with all accessories needed for flight. Inspection of a production sample against the manifest is the appropriate verification method because the requirement is about kit completeness, not functional performance. Testing a production sample (rather than a pre-production kit) catches omissions introduced during packaging line configuration.

Rationale: STK-REQ-013 requires controlled flight up to 15 knots and controlled descent (but not manoeuvre) in 16-25 knots. Direct flight testing in representative wind is the only method to validate the aerodynamic control authority claim. Simulation or analysis cannot predict actual stability margins for a low-cost foam aircraft where as-built surface tolerances affect lift and drag.

Rationale: STK-REQ-014 requires the FHSS link to co-exist with Wi-Fi and other RC aircraft. Only a live RF environment test with controlled co-channel interference sources (Wi-Fi APs and a second aircraft) can validate the FHSS channel diversity claim of SUB-REQ-032. Spectrum analyser confirms the test environment meets the interference level required to stress the FHSS algorithm.

Rationale: STK-REQ-012 requires mandatory safety labelling on all product surfaces. Inspection is the appropriate verification method for labelling requirements — testing cannot confirm text content. Multilingual requirements are regulatory obligations under EU Toy Safety Directive and CA Prop 65; failure to include all required markings results in market withdrawal.

Rationale: IFC-REQ-023 requires the receiver to refuse control from all transmitters except the bound one. This is a direct functional test of the bind protocol exclusivity claim, which is the primary mitigation for H-006 (RF cross-binding). Transmitter B must be of the same make and model to test the worst-case same-frequency scenario.

Rationale: IFC-REQ-024 specifies RSSI-triggered failsafe and re-link restoration. Replaces vague 're-link restores normal control' with a quantified criterion: all-axes (rudder, elevator, motor) restore within one 22ms frame period at the 45Hz update rate specified in IFC-REQ-004. Without enumerating which axes must restore, a partial restoration (e.g., motor only) would pass the test, leaving the aircraft uncontrollable during recovery.

Rationale: SUB-REQ-030 requires 10-bit (1024 step) stick resolution at 100 Hz. A logic analyser sweep of the full stick travel directly counts distinct output values and confirms the ADC rate. This test cannot be replaced by specification inspection because ADC non-linearity and mechanical dead-band can reduce effective resolution below the nominal bit depth.

Rationale: SUB-REQ-034 specifies MOSFET electrical ratings. Datasheet review (Analysis) is used for VDS and ID ratings as these cannot be easily measured in the assembled circuit. Rds-on is verified by direct 4-wire measurement on production samples because it is sensitive to bond wire resistance and assembly variation that may not match datasheet typical values.

Rationale: SUB-REQ-035 is a safety requirement (H-002 shoot-through mitigation). Oscilloscope measurement of gate signals on the production PCB is the only reliable method to verify dead-time because gate driver IC datasheet values are nominal and board parasitics (trace inductance, gate resistor tolerance) can reduce effective dead-time by 20-50 ns.

Rationale: Safety-critical requirement addressing LiPo thermal runaway risk after crash requires demonstration that non-technical parents can execute the procedure.

Rationale: Inadequate rise time causes shoot-through in the MOSFET bridge and out-of-range gate drive voltage causes either incomplete turn-on or gate oxide breakdown, both destroying the ESC.

Rationale: A 100 Hz sample rate prevents stick movement aliasing and 50 Hz RF frame rate provides sufficient control bandwidth for responsive flight. Dropped frames cause perceptible control lag for the child pilot.