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LSEAT Aerospace
PATENTED INNOVATION — DESIGNED TO EASA CS-25 & FAA FAR-25

Upgrade Economy Comfort Without Sacrificing Seat Density.

Ultra-lightweight (< 1,650 g / 3 seats) non-electric retrofit kit enabling 40° sleep mode. Zero AOG time, installed in < 15 minutes per seat.

Request the EASA Form 1 Dossier Run Fleet ROI Simulator

Download 2025 Technical Brochure

  • EASA Part 21J
  • FAA Part 21
  • 3 moving sub-parts
  • 0 motors

Integrated Kit Mass

< 1,650 g

For a 3-seat block. TSO tolerance < 5 kg on 2 seat track legs.

MRO Retrofit Time

< 15 min

Direct installation without removing seat track legs.

Aircraft On Ground

0 h

Zero forced airframe downtime.

Dynamic Crash Test

16G CS-25 / FAR-25

Automatic spring-return holds an unoccupied seat upright.

PATENTED COUPLED MOTION

Patented Kinematics & Coupled Glide

Two composite frames are inserted under the original seat pan. The backrest / seat pan motion is mechanically coupled: no electric motor, only 3 moving sub-parts, 16G CS-25.562 retention maintained in all four positions.

Passenger position simulator

Passenger position selection
Seat kinematics — schematic side view Schematic, not to scale. The backrest, the seat pan and the passenger silhouette are driven by the selected position. 0°
Readout 0°

16G Upright Sitting Mode

Upright seated position

Backrest recline
0°
Seat pan travel
0 mm
Retention
16G CS-25.562

16G CS-25.562 retention verified

  • 16G RETENTION ACTIVE

Seat pan travel amplified for clarity. Rear footprint measured against the certified seat-pitch envelope of the preceding row.

2 composite frames

Two pre-printed carbon frames are inserted under the original seat pan. No rework to the seat structure, no drilling, no seat pan removal.

3 moving sub-parts, 0 motors

Front frame, rear frame, return cam. Three moving parts, purely passive transmission, spring return to the sitting position.

0 W, 0 electronics

No power supply, no sensor, no aircraft wiring. 100% mechanical operation, on the ground and in flight, with no EMC impact.

INTERACTIVE 3D MASS MODEL

Kinematics in Three Dimensions

The same four certified positions, rendered as a real 3D solid model you can orbit. Two composite frames are inserted under the original seat pan, the backrest and seat pan motion is mechanically coupled, and only three sub-parts move: no motor, 0 W, spring return to upright.

Interactive 3D passenger position viewer

Kinematic position selection
Seat kinematics - schematic side view Simplified fallback schematic, not to scale. It is shown until the 3D model is loaded, and replaces it if the 3D renderer cannot start. The backrest, the seat pan and the passenger follow the selected position. 0°

Interactive 3D model region. Focus the model, then use the arrow keys to rotate it, plus and minus to zoom, and zero to reset the camera. The same commands are also available as buttons below the model, and the position selector above changes the kinematic state.

The 3D model loads on its own when this section scrolls into view. Seat pan travel is amplified for clarity.

Readout 0°

16G Upright Sitting Mode

Upright seated position

Backrest recline
0°
Seat pan travel
0 mm
Retention
16G CS-25.562

16G CS-25.562 retention verified

  • 16G RETENTION ACTIVE

Solid model of the seat, its two composite frames, the passenger mass and the seat-back IFE screen. The rear envelope annotation is drawn in Sleep Mode only. Seat pan travel is amplified for clarity.

2 composite frames

Two pre-printed carbon frames are inserted under the original seat pan. No rework to the seat structure, no drilling, no seat pan removal.

3 moving sub-parts, 0 motors

Front frame, rear frame, return cam. Three moving parts, purely passive transmission, spring return to the upright position for an unoccupied seat.

0 W, 0 electronics

No power supply, no sensor, no aircraft wiring. 100% mechanical operation, on the ground and in flight, with no EMC impact.

Certification dossier

Technical Specifications & EASA Form 1

Every figure below is covered by the EASA Part 21J engineering package: engineered architecture, Part 21G subcontracted production, mass margins and compliance with the CS-25.562 / FAR-25.562 cabin safety requirements. The full dossier is released on request.

Applicable references

  • EASA Part 21J
  • FAA Part 21
  • EASA CS-25.562
  • FAR-25.562
  • TSO-C127
  • 16G Dynamic Crash Test
Contractual LSEAT technical specifications and associated normative references
Category Parameter Value Normative reference
DELIVERABLES Certification release EASA Form 1 + Part 21J engineering package EASA Part 21J
DELIVERABLES Kinematic architecture 2 composite frames inserted under the original seat pan LSEAT patent
PRODUCTION Manufacturing Certified subcontract production EASA Part 21G
PRODUCTION Moving sub-parts 3 (no motor, no electronics) Part 21J dossier
MASS Integrated kit mass (3-seat block) < 1,650 g TSO tolerance
MASS Load on seat track legs < 5 kg / 2 legs TSO tolerance
MAINTENANCE MRO installation time < 15 min / seat, without removing seat track legs A-Check procedure
MAINTENANCE Direct maintenance cost reduction -75 % LSEAT manufacturer data
MAINTENANCE Electrical components 0 0 W
CERTIFICATION Dynamic crash test 16G CS-25 / FAR-25 CS-25.562 / FAR-25.562
CERTIFICATION Unoccupied seat return Spring-return to upright CS-25.562
CERTIFICATION Aircraft On Ground 0 h MRO procedure

Swipe the table sideways: the category column stays pinned.

Figures are LSEAT manufacturer engineering data, released with the EASA Form 1 documentation on request. The LSEAT 2025 brochure is a marketing publication and is not a technical datasheet.

Download the 2025 Brochure (PDF, 1.5 MB)

Marketing overview of the retrofit kit, published for fleet operators and MRO buyers. The Part 21J engineering dossier, the EASA Form 1 and the certification figures listed above are released on request to qualified operators, MROs and certification authorities.

FLEET FINANCIAL MODEL

Interactive Fleet ROI Simulator

A model built for Revenue, Cabin and Procurement directors. LSEAT is not sold: it is installed through a flexible rental model, with zero upfront investment and no hardware for the airline to own. Adjust your fleet, your retrofitted Economy seat inventory and your pricing policy: the ancillary revenue, the rental cost, the net benefit and the break-even load factor are recomputed in real time. Every displayed value derives exclusively from the assumptions you enter.

Fleet assumptions

12

Aircraft with the kit installed and in service

180

Excluded seats (business class, berths)

€45

Net unit revenue per passenger per flight

82 %

Annual load factor retained by the airline

1.0 ×

1.00 = full year of operation

€25

User hypothesis: the actual LSEAT tariff is quoted on request

Rental model status

Maximum exposure before free termination: €324,000 (6 months of rent).

Break-even from month 1
  • Rental model — no upfront investment
  • Free termination after 6 months

Annual ancillary revenue

€29,091,960

Sleep-mode surcharge, year 1

Total annual rental cost

€648,000

Recurring seat rent, year 1

Net annual benefit

€28,443,960

Ancillary revenue minus rental cost

Net monthly benefit per retrofitted seat

€1,097.37

Net annual ÷ seats ÷ 12

Break-even load factor

1.8%

Load factor that exactly covers the rent

Break-even passengers per year

14,400

Passengers that exactly cover the rent

Max exposure before free termination

€324,000

6 months of rent, then free exit

Cumulative ancillary revenue vs rental cost

  • Cumulative ancillary revenue
  • Cumulative rental cost
Year 1 Year 2 Year 3 Year 4 Year 5

Over 5 years: €145,459,800 in ancillary revenue against €3,240,000 of cumulative rental cost — net margin €142,219,800.

Aircraft in fleet : 12. Retrofitted Economy seats per aircraft : 180. Sleep-mode surcharge per passenger : €45. Average load factor : 82 %. Seasonality factor : 1.0 ×. Monthly rental fee per seat : €25

Indicative simulation. Based on the assumptions entered above. LSEAT is offered through a rental model with no upfront investment and free termination after six months; the actual rental tariff is quoted on request. This tool does not replace a commercial offer nor the Part 21J documentation package. The monthly rental fee and the passenger surcharge are user hypotheses, not certified values.

Request a Quoted Fleet Pricing

Quoted response within 5 business days, backed by the EASA Part 21J engineering package.

Engineering Enquiry

B2B Engineering Contact Hub

Direct line to the LSEAT Aerospace engineering team. Every enquiry is handled by an engineer, not by an automated form: technical response within 24 h, complete documentation on explicit request.

What you receive

Items issued on request, according to the maturity level of your programme.

  • EASA Form 1 Certificate of conformity, released on request after a full review of the certification file.
  • Part 21J Engineering Package Design definition, drawings, bills of material and preventive maintenance instructions.
  • Dynamic 16G Certification Notes CS-25.562 / FAR-25.562 substantiation, Y and Z axes, DMSO 9G / OY 4G seats.
  • MRO Installation Procedure Installation sequence, tooling, labour time and post-installation inspection.
  • Quoted Fleet Pricing Cost per seat, per aircraft, with batch scheduling and volume assumptions.

Direct contact

No generic form: you talk to the LSEAT Aerospace engineering team. Technical response within 24 h.

CS-25.562 FAR-25.562 Part 21J 0 W < 15 min / seat

Company / MRO / OEM address required.

Drawings, Part 21J files or specifications can be sent in reply to your e-mail. No file attachment is accepted by this form.

Privacy & GDPR

* Required fields — Technical response within 24 h