Structural floor track (transport aircraft)
Deep I- or T-section tracks that act as floor members, with a slotted crown on top. Produced to the airframe maker's drawing in 7075, 7050 or 7150 over-aged tempers, or titanium in wet zones.
Seat track and cargo track
Aircraft Seat Track Extrusions
An aircraft seat track is a high-strength aluminium extrusion with a slotted crown, set into the cabin floor so that seats, galleys and cargo fittings can be locked at any 1-inch position. It is both a mounting rail and part of the floor structure, and must hold seats in place under crash loads. Metline supplies seat-track extrusions and machined tracks in 7075, 7050, 7150 and 6061, plus airline-style L-track for vehicles, to customers worldwide.
- Slot pitch
- 1.000 in (25.4 mm)
- Main alloys
- 7075 · 7050 · 7150 · 6061
- Fittings
- MS33601-pattern studs
- Forms
- Extrusion or machined track
What is an aircraft seat track?
A seat track looks simple: a rail with a row of circular openings joined by a narrow slot. Seat legs carry stud fittings that drop through the openings, slide half a pitch and lock under the lips of the crown. Because the openings repeat every inch, an operator can change seat pitch or cabin layout without drilling the floor.
In transport aircraft the tracks are much more than rails. They run fore and aft across the floor beams, carry the floor panels at their edges, and transfer seat loads in turbulence and emergency landings into the fuselage. Certification rules require seats and their attachments to withstand high static and dynamic crash loads, so the track crown, its lips and its attachment to the beams are all sized for those cases.
The same track profile, in lighter alloys, is widely used outside aviation as "airline-style" or L-track for securing cargo in vans, trailers, rail cars and race transporters, and for wheelchair tie-downs in buses. Metline supplies both the aerospace and the commercial versions; the material and certification requirements are very different, so it is important to say which you need.
Types of seat track
Surface-mounted seat track
Lower-profile track bolted on top of a floor or structure, used in business jets, helicopters, light aircraft and modifications.
Light-aircraft seat rail
Adjustable pilot and passenger seat rails with pin holes or slots, often in 6061-T6 or 2024-T3511.
Cargo and logistic track
Flush or surface-mounted track for cargo nets, tie-down rings and pallets in freighter and combi cabins.
Airline-style L-track (commercial)
Surface or flush-mount track for vans, trailers, trucks and buses; usually 6061-T6 or 6005A-T6, mill finish or anodised.
Beveled logistic track
Commercial track with sloped edges so that wheeled loads roll over it without catching.
Standard seat-track geometry
Aerospace seat tracks are drawn to the airframe maker's or customer's drawing, but most share a common crown pattern so that standard seat fittings can be used.
Common crown features
- Opening pitch
- 1.000 in (25.4 mm) centre to centre, with cumulative pitch tolerance controlled over the track length
- Opening diameter
- About 0.785 in (19.9 mm) on many standard tracks
- Slot
- Continuous narrow slot between openings, into which the fitting's locking plunger or shear plunger engages
- Fitting compatibility
- MS33601 / AS33601-style single and double stud fittings
- Typical widths
- About 1.1 – 2 in for commercial and light-aircraft tracks; floor tracks to drawing
- Lengths
- 10, 12, 20 and 24 ft extrusions, cut and machined to drawing
Dimensions are typical. Always check track geometry against the seat or fitting maker's drawing; small differences in crown depth or lip width can prevent fittings from locking.
Openings can be machined in the extrusion, or the extrusion can be supplied plain for the customer to machine. Machining after extrusion and heat treatment is normal, followed by deburring and corrosion protection of the cut edges.
Seat-track alloys and tempers
| Alloy-temper | Typical use | Why |
|---|---|---|
| 7075-T73511 | Aircraft seat and floor tracks | High strength with good stress-corrosion resistance |
| 7075-T6511 | Surface-mounted and light-aircraft tracks | Peak strength where stress-corrosion risk is low |
| 7050-T76511 / T74511 | Floor tracks on modern airframes | Good strength, toughness and corrosion resistance |
| 7150-T77511 | Highly loaded floor tracks and beams | High strength with improved exfoliation resistance |
| 2024-T3511 | Light-aircraft seat rails, legacy tracks | Good fatigue properties |
| 6061-T6 / T6511 | Commercial L-track, cargo track, light aircraft | Economical, corrosion resistant, anodises well |
| 6005A-T6 / 6351-T6 | Commercial vehicle and bus tracks | Good extrudability with moderate strength |
An earlier version of this page also listed 5083 and 6063. These are not suitable for load-rated seat track: 5083 is not normally extruded into such complex hard shapes, and 6063 is too weak for crash loads. Titanium is preferred in the wettest floor zones of some airliners because aluminium tracks there are prone to corrosion.
Standards and certification requirements
| Area | Document | What it governs |
|---|---|---|
| Material | AMS-QQ-A-200/11 (7075), AMS 4340-series (7050), AMS 4345 (7150), ASTM B221 | Chemistry, temper, mechanical properties of the extrusion |
| Tolerances | ANSI H35.2, customer drawing | Cross-section, straightness, twist |
| Fittings interface | MS33601 / AS33601 | Stud-fitting pattern that the track must accept |
| Seat strength | 14 CFR 25.561 and 25.562; SAE AS8049; FAA TSO-C127 | Static and dynamic crash loads that seats and attachments must survive |
| Anodising | MIL-A-8625 Type II (sulphuric) or Type I (chromic) | Corrosion protection and wear surface |
| Quality | AS9100 supply chain where the buyer requires it; EN 10204 3.1 certificates | Traceability from cast to finished track |
For installation on a certificated aircraft, the track must also be an approved part for that aircraft, through the type design, a supplemental type certificate, a parts manufacturer approval or a field approval. Raw extrusion supplied to a material specification is not in itself an approved aircraft part.
Machining, finishing and inspection
Opening and slot machining
CNC machining of openings, fastener holes and end features to the drawing pattern, with pitch checked over the full length.
Cut to length
Square, deburred ends; jig holes and alignment features on request.
Anodising
Clear or black sulphuric anodising for commercial track; chromic or boric-sulphuric anodising for aerospace parts through qualified processors.
Sealing and primer
Corrosion-inhibiting primer and sealant on machined edges for tracks in wet zones.
Inspection
Dimensional, pitch, straightness and conductivity checks; first article inspection for new part numbers.
Marking
Part, alloy, temper and lot identification for traceability.
Corrosion and maintenance
Seat tracks sit at the lowest point of the cabin floor, so spilled drinks, cleaning fluids and condensation collect around them. The areas next to galleys, lavatories and doors are the most common sites of seat-track corrosion found during heavy maintenance checks.
- Specify over-aged tempers (T73, T76, T77) rather than T6 for structural floor tracks
- Seal floor-panel edges and fastener holes; keep drain paths clear
- Use track covers between seats to keep debris and fluids out of the slot
- Inspect crown lips for cracks and wear at frequently used seat positions
- Repair or replace damaged track sections according to the aircraft structural repair manual
How to order seat track
- SpecifyAlloy and temper, profile drawing, length, opening pattern and finish, quantity and the governing specification with its revision (e.g. AMS-QQ-A-200/11, customer drawing).
- ConfirmWe confirm the specification can be met, the tolerance class, any extra tests and the delivery terms (EXW, FOB, CIF or DAP).
- InspectMaterial is checked for dimensions, straightness and surface condition; tests named on the order are carried out or arranged with a third party.
- DocumentEach lot ships with a mill test certificate to EN 10204 3.1 showing chemistry and mechanical results, traceable to the cast or lot number.
- Pack and shipExport packing in sealed, moisture-protected wooden cases, coils on pallets or reels, shipped by sea or air to your port or door.
References and standards
- 14 CFR 25.562 – Emergency landing dynamic conditions (eCFR)
- SAE AS8049 – Performance Standard for Seats in Civil Rotorcraft, Transport Aircraft, and General Aviation Aircraft
- SAE AMS-QQ-A-200/11 – Aluminum Alloy 7075, Bar, Rod, Shapes, Tube and Wire, Extruded
- MIL-A-8625 – Anodic Coatings for Aluminum and Aluminum Alloys
- ASTM B221 – Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes
Aircraft seat track (aluminium / aluminum): frequently asked questions
What is the standard pitch of aircraft seat track?
1.000 in (25.4 mm) between opening centres, which lets seats and fittings be positioned in 1-inch steps.
Which alloy is used for airliner seat tracks?
High-strength 7xxx alloys in over-aged tempers, such as 7075-T73511, 7050-T76511 or 7150-T77511. Some aircraft use titanium tracks in wet areas.
Can I use aircraft seat track in a van or trailer?
Yes. Airline-style L-track in 6061-T6 or 6005A-T6 is common for cargo securing. Choose fittings and fasteners rated for the loads you need to restrain.
Is seat-track extrusion an approved aircraft part?
Not by itself. Material certified to a specification must still be made into a part approved for the specific aircraft through its type design, an STC, PMA or field approval.
Why do seat tracks corrode?
Fluids collect around them near galleys, lavatories and doors. Over-aged tempers, sealing, drainage and track covers reduce the risk.
Can you machine the openings?
Yes. Openings, fastener holes and end features can be CNC machined to your drawing, or plain extrusion can be supplied for your own machining.
Need seat track or L-track?
Tell us whether it is for aircraft or vehicle use, with the profile, alloy, length and finish. We will confirm supply and certification.
