{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "trim-tab",
 "name": "Trim tab and antiservo tab",
 "kind": "standard",
 "category": "Aircraft design",
 "group": "Control surfaces",
 "year": null,
 "question": "How does a trim tab work?",
 "tags": [
  "vehicle design",
  "control surfaces",
  "rc design",
  "aerodynamics",
  "guide"
 ],
 "aliases": [
  "trim tab",
  "elevator trim tab",
  "antiservo tab",
  "trim tab how it works",
  "servo tab",
  "anti servo tab stabilator",
  "rudder trim tab",
  "fixed trim tab"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "not-scanned",
 "les": false,
 "free_files": 0,
 "url": "https://xemstudio.com/objects/trim-tab/",
 "sheet_txt": "https://xemstudio.com/objects/trim-tab/sheet.txt",
 "sheet": {
  "basis": "Design rules and figures from the cited sources; example geometry by Xem Studio",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A trim tab is a small surface on a control surface's trailing edge that moves opposite to the surface, holding it deflected so the pilot needn't; full nose-down trim moves the elevator tab full up (FAA PHAK ch.6).",
   "On a stabilator an antiservo tab moves the same way as the surface to add feel and prevent over-control (FAA)."
  ],
  "table": {
   "columns": [
    "parameter",
    "value or range",
    "source"
   ],
   "rows": [
    [
     "Trim tab motion",
     "opposite to the surface",
     "FAA PHAK ch.6"
    ],
    [
     "Antiservo tab motion",
     "same direction as stabilator",
     "FAA PHAK ch.6"
    ]
   ]
  }
 },
 "sheet_text": "Trim tab and antiservo tab — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/trim-tab/  (sheet CC BY 4.0)\nBasis: Design rules and figures from the cited sources; example geometry by Xem Studio\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A trim tab is a small surface on a control surface's trailing edge that moves opposite to the surface, holding it deflected so the pilot needn't; full nose-down trim moves the elevator tab full up (FAA PHAK ch.6).\n- On a stabilator an antiservo tab moves the same way as the surface to add feel and prevent over-control (FAA).\n\nparameter  value or range  source\nTrim tab motion  opposite to the surface  FAA PHAK ch.6\nAntiservo tab motion  same direction as stabilator  FAA PHAK ch.6\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- FAA: Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25), Ch. 6 Flight Controls — web — Publisher's page; dimensions are facts — https://www.faa.gov/sites/faa.gov/files/08_phak_ch6.pdf\n\nNo true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.\nAPI: https://xemstudio.com/api/geometry?object=trim-tab\n",
 "sources": [
  {
   "publisher": "FAA",
   "title": "Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25), Ch. 6 Flight Controls",
   "url": "https://www.faa.gov/sites/faa.gov/files/08_phak_ch6.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "aileron",
  "frise-aileron",
  "differential-ailerons",
  "elevon",
  "flaperon",
  "spoiler"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn.",
 "mating": [],
 "faq": [
  {
   "q": "Which way does a trim tab move?",
   "a": "Opposite to its control surface (FAA PHAK ch.6)."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/trim-tab/index.md"
}