eVTOL ACOUSTIC INTELLIGENCE PLATFORM
WE MAKE AVIATION SILENT

From first rotor noise prediction to type certificate submission — SONONAI covers the complete eVTOL acoustic engineering workflow. Peer-reviewed physics, browser-based, no installation required.

⊛ ACOUSTIC ANALYSIS — SONIQ ◈ CERTIFICATION PATH — CERTIQ
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ACOUSTIC ANALYSIS
Rotor noise · Cabin treatment · SPL mapping · Benchmarks
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ACOUSTIC CERTIFICATION
ICAO Annex 16 · EASA SC-VTOL-01 · EPNdB · Margins
SCROLL
01
ACOUSTIC PREDICTION · SONIQ

PREDICT NOISE.
DESIGN FOR SILENCE.

Real-time rotor noise computation using Lowson, FW-H, and BPM models. Far-field SPL heatmaps, cabin treatment design, directivity patterns — all in one browser-based tool. 18 aircraft types, 8 acoustic models.

OPEN SONIQ →
02
CERTIFICATION PATHWAY · CERTIQ

STRUCTURE COMPLIANCE.
FLY WITH CONFIDENCE.

Structured noise certification support from acoustic prediction to EPNdB calculation. ICAO Annex 16, EASA SC-VTOL-01, and FAR Part 36. Certification margin analysis across all measurement points.

OPEN CERTIQ →
18
AIRCRAFT TYPES
8
ACOUSTIC MODELS
12
COMPANIES BENCHMARKED
±1.6
dB MEAN ERROR
100%
BROWSER-BASED
WORKFLOW

HOW SONONAI WORKS

Two tools, two purposes, one platform. Switch between acoustic prediction and certification documentation seamlessly.

01
AIRCRAFT DATABASE
SELECT YOUR AIRCRAFT
Choose from 18 preconfigured aircraft — Joby S4, Archer Midnight, Lilium Jet, Volocopter 2X, EHang 216, DJI M300, Wingcopter 198 and generic UAM layouts. Physics parameters auto-loaded: rotor count, diameter, RPM, blade count, chord, disc loading.
02
LOWSON · FW-H · BPM
RUN ACOUSTIC ANALYSIS
Instant computation of thickness noise, loading noise, and BPM broadband across 4 live charts: SPL spectrum with BPF tones highlighted, exterior vs cabin interior, harmonic levels, and polar directivity pattern.
03
JCA · HELMHOLTZ · MPP · CLD
DESIGN CABIN TREATMENTS
Apply 8 acoustic treatment models to the cabin interior spectrum. Each model shows absorption α(f) and cabin noise reduction charts. Adjust area fraction and see real-time SPL reduction.
04
ISO 9613 · INVERSE SQUARE LAW
MAP FAR-FIELD RADIATION
Generate HD ground-level SPL heatmap with configurable rotor positions, ground absorption, and A-weighting. Dashed contour rings at 75/65/55/45 dB certification limits. SPL vs distance chart.
05
12 AIRCRAFT · ±2.3 dB MAX
COMPARE WITH BENCHMARKS
Validate your predictions against 12 published eVTOL noise measurements from Joby, Archer, Lilium, Volocopter, EHang, Wisk, DJI, Wingcopter, Amazon, and NASA. Mean absolute error 1.6 dB.
SONIQ · LIVE PREVIEW
01
SONIQ OUTPUT
IMPORT ACOUSTIC DATA
CERTIQ reads SONIQ's one-third octave SPL spectra at each measurement microphone position for hover, take-off, and flyover reference procedures.
02
ISO 9613-1
ATMOSPHERIC CORRECTION
Normalise all levels to ICAO reference atmosphere (25°C, 70% RH). Frequency-dependent absorption correction α(f) applied at slant distance to microphone.
03
ICAO DOC 9501
PNL + TONE CORRECTION
Perceived Noise Level from noy conversion tables. Tone correction C where spectral irregularities exceed 1.5 dB slope criterion. PNLT = PNL + C at each timestep.
04
ANNEX 16 APPENDIX 2
EPNL CALCULATION
EPNdB = PNLT_max + duration correction D + max tone correction. Full uncertainty budget. Compliant with ICAO Doc 9501 procedure for VTOL aircraft.
05
EASA SC-VTOL-01 / ICAO CH.14
COMPLIANCE MARGIN
Compare EPNdB against MTOW-dependent limits. Cumulative margin across flyover, approach, and lateral measurement points. Report to 0.1 EPNdB resolution.
CERTIQ · CERTIFICATION MARGIN
INDUSTRY VALIDATION

BENCHMARKED AGAINST
PUBLISHED MEASUREMENTS

SONIQ predictions validated against 12 published eVTOL and UAV noise measurements. Physics model calibrated per aircraft against stated observation conditions.

AIRCRAFT CATEGORY REPORTED SONIQ ERROR CONDITION
* Lowson (1970) + FW-H + BPM (1989). Calibrated per aircraft vs published measurements. Rizzi et al. (2020) NASA/TM-220630.
TOOL CAPABILITIES

WHAT EACH TOOL DOES

SONIQ handles acoustic physics. CERTIQ handles certification structure. Together they cover the complete noise engineering workflow for eVTOL type certification.

⊛ OPEN SONIQ → ◈ OPEN CERTIQ →
SONIQ
ACOUSTIC PREDICTION
✈
18 AIRCRAFT CONFIGURATIONS
Quadcopter, hex, octo, coaxial, tandem, lift+cruise, Joby S4, Archer Midnight, Lilium Jet, Volocopter 2X, EHang 216, Wisk Cora, DJI M300/600, Wingcopter 198, Zipline P2, tilt-wing, tiltrotor — all with physics-appropriate defaults.
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4 LIVE ACOUSTIC CHARTS
SPL spectrum with BPF harmonic overlay · Exterior vs cabin interior SPL · Harmonic level decay (8 harmonics) · Polar directivity pattern. All update in real time as parameters change.
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8 CABIN TREATMENT MODELS
JCA 5-parameter foam · Delany-Bazley · Miki · Biot limp-frame · Helmholtz resonator · Micro-perforated panel (MPP) · Constrained layer damping (CLD) · Glazing. Each with absorption + noise reduction charts.
🗺
HD FAR-FIELD SPL HEATMAP
Multi-rotor incoherent summation at configurable positions. Ground absorption α. A-weighting. Dashed contour rings at 75/65/55/45 dB certification limits. Hover readout at any point.
⊟
INDUSTRY BENCHMARKS
12-aircraft comparison with reported vs SONIQ predictions. Error bar chart, MTOW scatter, and per-aircraft calibration table with physics parameters and published references.
§
COMPLETE GLOSSARY
30+ defined terms with full formulae and citations covering fundamental quantities, rotor parameters, noise metrics, porous media, resonators, and certification standards.
CERTIQ
CERTIFICATION TOOLKIT
📋
ICAO ANNEX 16 DATA PACKAGE
Structures SONIQ acoustic predictions into ICAO Annex 16 Appendix format. Generates flyover, approach, and lateral measurement point data with all required metadata and uncertainty budgets.
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EPNL CALCULATION CHAIN
Full ICAO Doc 9501 procedure: PNL from noy tables → tone correction C → duration correction D → EPNdB. Uncertainty budget per Appendix 2. Traceable to each standard and chapter.
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FLIGHT PATH ANALYSER
Reference procedure definition for hover, take-off, and overflight. Microphone array placement per SAE ARP1779. Ground-to-aircraft slant distance and geometry calculations at each timestep.
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NOISE MARGIN CALCULATOR
Certified EPNdB versus MTOW-adjusted ICAO Chapter 14 limits. Cumulative margin across all measurement points. Design trade-study: shows how rotor diameter, RPM, and blade count affect margin.
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ATMOSPHERIC CORRECTION
ISO 9613-1 absorption correction to ICAO reference conditions (25°C, 70% RH). Day/night ambient corrections per ISO 1996-2. Required for all noise certification measurement submissions.
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8 CERTIFICATION STANDARDS
ICAO Annex 16 Vol. I · EASA SC-VTOL-01 (2022) · SAE ARP1779 · SAE ARP1580 · ISO 9613-1/-2 · IEC 61672-1 · FAA AC 36-4C · ICAO Doc 9501 — all documented with chapter-level traceability.
LIVE VISUALISATIONS

SEE THE PHYSICS IN ACTION

Every visualisation in the landing page is computed live from the same physics model that runs inside SONIQ. No pre-rendered images.

FAR-FIELD SPL HEATMAP · HOVER
BPF DIRECTIVITY · LOWSON MODEL
THICKNESS NOISE · LOWSON (1970)
Monopole radiation from blade volume displacement. SPL ∝ B²Ω²R²chord·τ/r. Dominant at high tip Mach number (M_tip > 0.6). Scales with N rotors.
LOADING NOISE · FW-H (1969)
Dipole radiation from unsteady aerodynamic forces. SPL ∝ B·T·Ω/a₀·ρ·r². Dominant source in eVTOL hover at low tip Mach. Phase-adjusted for climb, cruise, approach.
BROADBAND · BPM (1989)
Trailing-edge, separation, and tip vortex self-noise. SPL ∝ ρ²a³·chord·δ*·M⁵/r². Boundary layer displacement thickness δ* from NACA 0012 blade-element data.
A-WEIGHTING · IEC 61672
Applied at blade-passing frequency BPF = B×RPM/60. Low BPF (EHang: 53Hz) penalised by −26 dB. High BPF (Lilium: 400Hz) penalised by only −5 dB.
GROUND REFLECTION · ISO 9613
Coherent ground reflection with configurable absorption coefficient α. Hard ground (asphalt): α=0. Soft ground (grass): α=1. Applied as correction to far-field SPL.
MULTI-ROTOR SUMMATION
Incoherent energy summation across all rotors: SPL_total = 10·log₁₀(Σ 10^(SPLᵢ/10)). Each rotor's contribution computed at its geometric position relative to the observer.
REFERENCES

BUILT ON PEER-REVIEWED
AEROACOUSTICS

No black boxes — every calculation traces to a published, peer-reviewed source.

01
THICKNESS NOISE
Lowson (1970)
J. Acoust. Soc. Am. 47(1B):371. BPF harmonics via Fourier decomposition. Monopole rotating source.
02
LOADING NOISE
Ffowcs Williams & Hawkings (1969)
Phil. Trans. R. Soc. A 264:321. Dipole from unsteady forces. Dominant in eVTOL hover.
03
BROADBAND (BPM)
Brooks, Pope & Marcolini (1989)
NASA RP-1218. Trailing-edge & tip self-noise. Industry standard semi-empirical model.
04
JCA POROUS MEDIA
Johnson-Champoux-Allard
J. Fluid Mech. 176 + J. Appl. Phys. 70. 5-parameter TMM on rigid backing.
05
MICRO-PERF PANEL
Maa, D.Y. (1998)
J. Acoust. Soc. Am. 104(5):2861. Sub-mm viscous resistance. Aircraft-grade liner.
06
CERTIFICATION
ICAO Annex 16 / EASA SC-VTOL-01
Vol. I Amendment 13 + SC-VTOL-01 (2022) + SAE ARP1779. EPNdB, limits, procedures.
CONTACT

GET IN TOUCH

For licensing, custom acoustic analysis, eVTOL certification support, or any technical questions about rotorcraft noise engineering.

SONONAI is developed by Zirconique — an aerospace acoustics consultancy specialising in rotorcraft and advanced air mobility noise engineering.

✉
EMAIL
info@sononai.com
 🌐
WEBSITE
www.sononai.com
 ⊛
ACOUSTIC TOOL
Launch SONIQ
 ◈
CERTIFICATION TOOL
Launch CERTIQ