Specifications by size
Head dimensions are derived from the ratios the FAA Airframe Handbook states — head diameter 2D, head height approximately 0.425D — not copied from a dimensional table. Neither of our primary sources publishes one for AN470, so the arithmetic is shown rather than hidden.
Manufacturing tolerances are in the NASM/MS standard, which we have not sourced. For a job requiring guaranteed dimensions, go to the standard.
| Shank Ø (D) | Dash | Head Ø (2D) | Head height (0.425D) | Drill | Min edge dist. (2D) |
|---|---|---|---|---|---|
| 3/32" (0.0938") | -3 | 0.188" | 0.040" | #40 (0.0980") | 0.188" |
| 1/8" (0.1250") | -4 | 0.250" | 0.053" | #30 (0.1285") | 0.250" |
| 5/32" (0.1563") | -5 | 0.313" | 0.066" | #21 (0.1590") | 0.313" |
| 3/16" (0.1875") | -6 | 0.375" | 0.080" | #11 (0.1910") | 0.375" |
| 1/4" (0.2500") | -8 | 0.500" | 0.106" | F (0.2570") | 0.500" |
Dash number is the diameter in thirty-seconds. Length is a separate dash after a hyphen and is in sixteenths — see the length section below.
What it is and where it goes
AN470 is the universal head: a rounded protruding head with a flat bearing face, roughly twice the shank diameter across. It replaced the older round (AN430), brazier (AN455) and flat (AN442) heads for most new work, because one head profile covers what previously took three.
It goes anywhere aerodynamic smoothness does not matter — internal structure, ribs, stringers, bulkheads, non-flush skin joints, and the majority of what a homebuilder drives. Where the surface must be flush, the answer is AN426 instead — whose own spec page is not published yet, because neither FAA source carries its head dimensions and we will not invent them.
A universal head is stronger than a countersunk one in the same size, because countersinking removes material from the top sheet. That is why the minimum edge distance is 2D here and 2.5D for a flush rivet, and why you do not countersink where you do not have to.
Available alloys
Which alloy the head marking tells you, and what it means for handling. The alloy is a separate decision from the head shape and is called out separately in the part number.
| Code | Alloy | Head marking | Handling |
|---|---|---|---|
| A | 1100 | Plain | Non-structural only. |
| AD | 2117-T4 | Indented dimple | Drive as received, store indefinitely. The default. |
| D | 2017-T4 | Raised teat | Icebox above 3/16" diameter. |
| DD | 2024-T4 | Raised double dash | Icebox, all sizes. Strongest of the common aluminum rivets. |
| B | 5056-H32 | Raised cross | For magnesium structure. Chosen for galvanic compatibility. |
AC 43.13-1B Table 4-8 also lists a 7075-T73 rivet marked with three raised dashes as available in this head style. Full details on the rivet identification chart.
Reading the part number
AN470AD4-5 breaks down as: AN470 universal head · AD alloy 2117-T4 · 4 shank diameter in thirty-seconds (4/32" = 1/8") · -5 length in sixteenths (5/16").
Two different fractions in one part number is not a mistake and it is the most common misreading. Diameter in 32nds, length in 16ths, always.
MS20470AD4-5 is the identical rivet. Drawings use whichever designation matches their vintage.
Substitutions and equivalents
MS20470 for AN470: direct, same rivet.
Alloy substitution is not free. AD is not a drop-in for DD because it is easier to drive — DD is specified where the joint needs the strength. Going the other way, driving DD where AD was called out, means handling icebox rivets and a harder drive for strength nobody asked for. The drawing picked the alloy for a reason.
Universal for countersunk is a change to the external surface and to the required edge distance. Not a shop-floor substitution.
Going up a diameter is the standard remedy for an enlarged or damaged hole, and it is a repair-design decision against approved data — not a fix for a layout that came out wrong. Note that edge distance and pitch minimums scale with D, so the surrounding geometry gets tighter, not looser.
Blind rivets are not equivalents. A CherryMAX may be dimensionally interchangeable with a solid rivet size for size, but where it may be substituted is governed by approved data.
Installation notes
Length. Total length = grip + 1.5D, rounded up to the next 1/16". The 1.5D is the shank allowance that upsets into the shop head. Our rivet length calculator does the arithmetic and returns the dash number.
Hole. Drill to the size in the table above — two to four thousandths over the shank, which is designed-in clearance, not slop. The rivet swells to fill it when driven.
Layout. Minimum edge distance 2D, preferred 2.5D, maximum 4D. Minimum pitch 3D, typical 4D-6D.
Shop head. Aim for roughly 1.5D across and 0.5D high, checked with a rivet gauge. AC 43.13-1B Figure 4-6(a) gives 1½D as a minimum width and ½D as a minimum height, so aim above them rather than at them.
Deburr both faces of every hole before assembly. A joint riveted over burrs has a gap in it, and it is the step most often skipped.
Where to buy
Both distributors are real, live and verified. We link to their own category pages so you see current stock rather than a price we copied months ago.
The Aviation Point links to third-party manufacturer and distributor websites. We may earn a commission on purchases made through these links, at no additional cost to you. No affiliate agreement is in place with either distributor at the time of writing.
Sources
- FAA-H-8083-31, AMT Handbook — Airframe, Volume 1, Figure 4-74 — universal head geometry stated as ratios — head diameter 2D, head height about 42.5% of shank diameter. The head columns above are computed from these, and no dimensional table for AN470 appears in either source.
- FAA AC 43.13-1B CHG 1, Chapter 4, Table 4-8 and ¶4-57 — which alloys are available in this head style, icebox handling, and the 2D minimum edge distance and 3D minimum pitch.
- NASM20470 / MS20470 — the governing standard for manufactured dimensions and tolerances. Not sourced by us — cited here so you know where the authoritative figures live.