Aerospace Wire and Cable: AS22759, M27500 and Coax
Aerospace hookup wire is bought to SAE AS22759 slash sheets that fix insulation, conductor plating, voltage and temperature; shielded multi-conductor cable to the M27500 designation now under NEMA WC 27500; and coax to MIL-DTL-17. The part number carries the slash sheet, gauge and color, so buy by full number and reel lot.
Updated
Wire and cable types and where they are used
Four document families cover most of what goes into a flight or GSE harness. The choice is driven by temperature, weight, abrasion and what the conductor is carrying.
| Type | Governing document | Typical use |
|---|---|---|
| Single conductor hookup wire, fluoropolymer insulated | SAE AS22759 slash sheets (M22759 part numbers) | Airframe and vehicle harnesses, box wiring, connector pigtails |
| Shielded and jacketed multi-conductor cable | NEMA WC 27500 (M27500 part numbers, formerly MIL-DTL-27500) | Signal pairs, data, sensor runs that need a shield |
| Coaxial RF cable | MIL-DTL-17 (M17 part numbers) | Antennas, telemetry, radar and RF test cables |
| Polyimide insulated wire (legacy) | MIL-DTL-81381 slash sheets | Older aircraft wiring kept for sustainment |
How these are built into a harness, tested and documented is covered on the wire harness sourcing page, including the current AS22759 revision. This page is about buying the wire itself.
The specifications that govern it, and their status
Most aerospace wire documents moved from military to industry ownership, but the M-prefixed part numbers stayed. Status below is from EverySpec, NASA and the issuing bodies as of October 2026.
| Document | What it covers | Status we verified |
|---|---|---|
| SAE AS22759 | Fluoropolymer insulated copper and copper alloy wire, by slash sheet | Active SAE standard; part numbers still read M22759 |
| NEMA WC 27500 | Shielded and jacketed multi-conductor cable built from listed wire types | Replaced MIL-C-27500 as a non-government standard; NASA updated its parts list for the transfer in October 2012 |
| MIL-DTL-17 Rev J, Amendment 2 (22 Feb 2019) | Flexible and semirigid RF cables with solid and semisolid dielectric cores | Active |
| MIL-DTL-81381 | Fluorocarbon and polyimide insulated wire | Base document listed as inactive; 2017 slash sheet revisions carry an inactive for new design note |
| MIL-STD-681 Rev F (7 Mar 2012) | Color coding for hookup and lead wire | Current revision per published copies |
| SAE AS50881 | Wiring design and installation for aerospace vehicles, including identification | Adopted by DoD in place of MIL-W-5088L |
AS22759 slash sheets: insulation, plating and temperature
The slash sheet is the whole design choice. NASA's parts selection list groups the common sheets like this:
| Slash sheet | Insulation | Conductor | Rating |
|---|---|---|---|
| /11 | PTFE | Silver-coated copper | 600 V, 200 C |
| /12 | PTFE | Nickel-coated copper | 600 V, 260 C |
| /16 | Extruded ETFE, medium weight | Tin-coated copper | 600 V, 150 C |
| /18 | Extruded ETFE, light weight | Tin-coated copper | 600 V, 150 C |
| /32 | Crosslinked ETFE, light weight | Tin-coated copper | 600 V, 150 C |
| /33 | Crosslinked ETFE, light weight | Silver-coated high strength copper alloy | 600 V, 200 C |
| /34 | Crosslinked ETFE, normal weight | Tin-coated copper | 600 V, 150 C |
| /43 and /44 | Crosslinked ETFE, normal and light weight | Silver-coated copper | 600 V, 200 C |
| /41 and /45 | Crosslinked ETFE, normal and light weight | Nickel-coated copper | 600 V, 200 C |
The trade-offs follow the plating. Tin-coated conductors cap the wire at 150 C, silver allows 200 C, and nickel is used where the insulation goes to 260 C. Light weight walls save mass on a long harness but give less abrasion margin than normal or medium weight. High strength copper alloy conductors, as on /33, help fine gauges survive handling and vibration. Diameter differences are real: NASA lists 22 AWG /32 at 0.043 inch finished diameter against 0.052 inch for /16, which changes how many wires fit a backshell or a connector grommet range.
How the wire and cable part numbers are built
Hookup wire. NASA's ordering example is M22759/11-22-90: specification, detail sheet, wire size in AWG, then a color code per MIL-STD-681. Applied to a common part:
| Field | M22759/16-22-9 | Meaning |
|---|---|---|
| Specification | M22759 | SAE AS22759 wire |
| Detail sheet | /16 | Extruded ETFE, tin-coated copper, 600 V, 150 C, medium weight |
| Size | -22 | 22 AWG, 19 strands of 34 AWG per NASA's table |
| Color | -9 | White under MIL-STD-681, where 0 to 9 run black, brown, red, orange, yellow, green, blue, violet, gray, white; NASA's own example ends in -90, where added digits specify stripe colors |
Shielded cable. A wire distributor's anatomy guide for NEMA WC 27500 decodes M27500-20RC2S06 as follows:
| Field | Code | Meaning |
|---|---|---|
| Specification | M27500 | NEMA WC 27500 cable |
| Identification method | - | Conductor color coding and shield coverage method, set by a single character |
| Size | 20 | 20 AWG conductors |
| Basic wire | RC | M22759/11 conductors |
| Conductors | 2 | Two conductors (cables run from 1 to 15) |
| Shield | S | Single round silver-plated copper braid, 200 C (T is tin-plated, 150 C; N is nickel-plated, 260 C; U is no shield) |
| Jacket | 06 | Single white PTFE jacket, 260 C (00 is no jacket; 14 white ETFE, 150 C; 23 white modified crosslinked ETFE, 200 C) |
The cable is only as hot as its weakest element: a 200 C wire under a tin braid or ETFE jacket is a 150 C cable. Check all three codes against the zone temperature.
Coax. MIL-DTL-17 cables are bought by slash sheet and RG designation, for example M17/75-RG214. Some sheets in circulation still reference older general specification revisions, so ask which revision your program accepts.
MIL-DTL-81381 polyimide wire: a historical note
MIL-DTL-81381 covers fluorocarbon and polyimide insulated wire that was widely used on aircraft for its thin wall and light weight. The base document is listed as inactive, and its slash sheets revised in 2017 carry the note inactive for new design. Buy it only to repair or extend existing wiring built with it, and do not select it for a new drawing. If a legacy drawing calls it out, confirm with engineering whether a current AS22759 type is approved as a replacement before the harness is built.
Marking, identification and fluorine outgassing
Wire identification is part of the installation requirement, not an afterthought. SAE AS50881 sets wiring design and installation requirements for aerospace vehicles, and DoD adopted it in place of MIL-W-5088L.
- Hot stamp. SAE ARP5369A states that hot stamp marking is prohibited on aerospace vehicle wiring required to conform to AS50881, and encourages methods that do not deform insulation, such as ink jet, dot matrix or UV laser, especially on walls under 0.010 inch.
- UV laser. SAE AS5649 is the UV laser wire marking process standard; the current edition listed by ANSI is AS5649B (2025). Wire must be specified as UV laser markable for the method to work, so put that on the PO if your harness shop laser marks.
- Fluorine outgassing. NASA's GSFC advisory NA-GSFC-2003-03 warns that fluoropolymer insulation such as ETFE can outgas trace fluorine, which in sealed packaging forms hydrofluoric acid that corrodes nickel and gold. Store terminated wire and pre-wired connectors in open packaging with humidity control.
Shelf life, storage and lot traceability
Lot traceability is the part of wire buying that most often breaks. A harness shop cuts many lengths from one reel, so the reel identity has to follow every length to the harness serial number.
- Require the manufacturer's certificate of conformance and the distributor's certificate for each reel, with the reel or lot number on both.
- Ask for footage, manufacture date and reel label that match the certificate.
- Do not assume wire has no shelf life. We did not find a single shelf life rule across the AS22759 family, so check whether your program, prime or the manufacturer assigns one, and ask for the manufacture date so the question can be answered.
- Specify storage: reels covered, away from UV and heat, and no sealed long-term storage of terminated fluoropolymer wire.
- For cut lengths or rewound reels from a distributor, require that the original manufacturer lot is carried over to the new label and certificate.
Our certs and traceability page explains what a complete cert trail looks like.
What to put on the purchase order
- Full part number: M22759 sheet, gauge and color; M27500 identification, size, basic wire, conductor count, shield and jacket codes; or M17 sheet and RG number.
- Governing document and revision (AS22759, NEMA WC 27500, MIL-DTL-17), and any NASA or prime parts list that limits choices.
- Approved manufacturers or a qualified source requirement where your program sets one.
- Source: manufacturer or its authorized or franchised distributor, with lot traceability back to the manufacturer.
- Length per reel, minimum continuous length and whether cut lengths are acceptable.
- UV laser markable requirement where the harness is laser marked.
- Certificates: manufacturer and distributor certificates of conformance with reel or lot number, and test data if your program requires it.
- Packaging and storage requirements, including reel covers and no sealed long-term storage of terminated wire.
Counterfeit and quality risks, and how to receive it
Wire fraud is mostly mislabeling: a commercial wire on an M22759 reel label, a different slash sheet under the same gauge and color, or rewound remnants with no traceable lot. The print legend is the first line of defense.
How DFARS applies. DFARS 252.246-7008 (Jan 2023) sets authorized-source rules for electronic parts, defined as integrated circuits, discrete electronic components and circuit assemblies. Wire and cable are not in that definition. Programs may still require authorized sources for wire under their own contract terms or quality clauses, so read your flow-downs rather than assuming either way. Our counterfeit parts avoidance guide covers the broader controls.
At receiving:
- Read the insulation print and confirm it matches the reel label and certificate.
- Measure finished diameter against the slash sheet table; a /16 and a /32 of the same gauge differ visibly.
- Check conductor plating color at a cut end: tin, silver and nickel look different.
- For cable, strip a sample to confirm conductor count, shield type and jacket against the M27500 codes.
- Quarantine reels with no lot number or mismatched footage.
See receiving inspection for dock procedures.
How we source wire and cable
We do not stock wire, show prices or act as an authorized distributor for any wire maker. We source the exact M22759, M27500 and M17 part numbers on your drawing from manufacturers and their authorized and franchised distributors, with reel lot certificates delivered with the order.
- Reels or cut lengths bought alone, or kitted with connectors and contacts for a harness build.
- Wire combined with the harness build itself, so one PO covers material and assembly with traceability carried through.
- Legacy types such as MIL-DTL-81381 chased for sustainment; see obsolete aerospace parts.
Related parts: circular connectors, contacts, backshells and terminals and the electrical parts overview. For harness pricing drivers, see wire harness cost.
Request wire and cable
Send part numbers, lengths and any approved manufacturer list through the harness and wire quote form. Telling us whether you need full reels or cut lengths, and whether wire must be laser markable, decides which sources can quote. A person replies within one business day, and every order ships with a certificate of conformance.
Send the job. A person replies within 1 business day.
Part, quantity and date are enough to start. Drawings and the mutual NDA follow by reply, and controlled programs never send technical data through this site.
We have it.
Reference . A person replies within 1 business day. Watch for our email from [email protected].
Questions
What does M22759/16-22-9 mean?
It is SAE AS22759 slash sheet 16 wire: extruded ETFE insulation, tin-coated copper conductor, 600 volts, 150 C, medium weight wall. The 22 is the AWG size, built from 19 strands of 34 AWG per NASA's parts list, and the 9 is the MIL-STD-681 color code for white. Additional digits after the base color specify stripes; NASA's ordering example, M22759/11-22-90, shows the two digit form.
Is M27500 cable still a valid callout?
Yes, the M27500 part numbers are still used, but the governing document moved from the military specification to NEMA WC 27500, and NASA recorded that transfer in its parts list in October 2012. Check which document your drawing cites. If it still names MIL-C-27500 or MIL-DTL-27500, ask engineering whether NEMA WC 27500 product is accepted against it.
Should I use tin, silver or nickel plated wire?
Match the plating to the temperature. In NASA's AS22759 listing, tin-coated sheets such as /16, /32 and /34 are rated 150 C, silver-coated sheets such as /11, /33 and /43 are rated 200 C, and nickel-coated /12 is rated 260 C with PTFE insulation. Use the lowest rating that covers the zone with margin, and remember the cable shield and jacket can lower the cable's rating.
Can I still buy MIL-DTL-81381 wire?
It is available from some sources, but the base document is listed as inactive and its 2017 slash sheets are marked inactive for new design. Use it only to repair or extend existing wiring built with it, under your engineering authority's direction. For new harnesses, the drawing should call a current AS22759 type.
Why does my harness shop care whether wire is laser markable?
SAE ARP5369A says hot stamp marking is prohibited on wiring that must conform to AS50881 and encourages marking methods that do not deform the insulation, including UV laser. UV laser marking under SAE AS5649 only works on wire specified as UV laser markable, so buying the wrong grade forces the shop to use sleeves or another method.
Related
Sources
- NASA NEPP, AS22759 part number ordering explanation and slash sheet list
- NASA NEPP, AS22759/16 ETFE wire, tin-coated copper, 150 C
- NASA NEPP, AS22759/32 ETFE wire, light weight, 150 C
- NASA NEPP, revision history for NEMA WC 27500 listing
- Wiremasters, M27500 / NEMA WC 27500 part anatomy guide
- MIL-STD-681F identification coding for hookup and lead wire
- EverySpec, MIL-DTL-17J Amendment 2 (22 Feb 2019)
- SAI Global, MIL-DTL-81381/11 Rev D (2017), inactive for new design
- ANSI Webstore, SAE ARP5369A guidelines for wire identification marking
- ANSI Webstore, SAE AS5649B wire and cable marking process, UV laser (2025)
- EverySpec, DoD adoption notice for SAE AS50881 superseding MIL-W-5088L
- NASA NEPP, micro-D application notes citing GSFC advisory NA-GSFC-2003-03
Ready to
source it?
A person replies within 1 business day. NDA first.
Request a quote