---
title: "Proposal for Development in the Mathematics Division of an Automatic Computing Engine (ACE)"
authors:
  - "Alan M. Turing"
year: 1946
venue: "National Physical Laboratory report"
arxiv: null
doi: null
source: "https://www.npl.co.uk/getattachment/ea5c6585-0929-4713-962c-2306f8dcf1f2/turing-proposal-Alan-LR.pdf?lang=en-US"
topics:
  - ace
  - computer-architecture
  - turing
  - stored-program
seed_rank: 522
seed_batch: "foundations-greats-2026-08-13"
reviewed: "2026-08-13"
pool: "systems"
relevance_score: 9
lineage: foundations-of-computing
cites:
  - title: "First Draft of a Report on the EDVAC"
    url: "https://web.mit.edu/STS.035/www/PDFs/edvac.pdf"
    year: 1945
    arxiv: null
    doi: "10.5479/sil.538961.39088011475779"
  - title: "On Computable Numbers, with an Application to the Entscheidungsproblem"
    url: "https://doi.org/10.1112/plms/s2-42.1.230"
    year: 1936
    arxiv: null
    doi: "10.1112/plms/s2-42.1.230"
  - title: "Preliminary Discussion of the Logical Design of an Electronic Computing Instrument"
    url: "https://www.ias.edu/sites/default/files/library/pdfs/ecp.preliminarydiscussion.pdf"
    year: 1946
    arxiv: null
    doi: null
  - title: "The Preparation of Programs for an Electronic Digital Computer"
    url: "https://archive.org/details/preparationofpro00wilk"
    year: 1951
    arxiv: null
    doi: null
see:
  - "542-first-draft-of-a-report-on-the-edvac"
  - "515-on-computable-numbers-with-an-application-to-the-entscheidun"
  - "543-preliminary-discussion-of-the-logical-design-of-an-electroni"
  - "572-the-preparation-of-programs-for-an-electronic-digital-comput"
---

# Proposal for Development in the Mathematics Division of an Automatic Computing Engine (ACE)

## One-sentence takeaway

Turing's ACE report is a complete stored-program machine design—instruction set, delay-line memory, subroutine discipline—written by the author of the universal machine.

## Why it matters here

Pairs with EDVAC as the UK stored-program vision. Anoptic's runtime (program and data in one memory, libraries of kernels, speed as a first-class constraint) is closer to ACE's "detailed code and a library" culture than to a pure logic paper.

## Key ideas

- Drafted late 1945, submitted to the NPL Executive Committee in February 1946; archive title *Proposed Electronic Calculator*.
- Specifies a mercury delay-line store, a compact instruction code, and an emphasis on subroutine libraries so the human does not recode elementary operations.
- Explicitly engages von Neumann's EDVAC draft while pushing a different engineering trade (fewer tubes, more ingenious coding).
- Lineage runs through Pilot ACE (1950) and the later production ACE.

## Caveats

## Links

- NPL PDF: https://www.npl.co.uk/getattachment/ea5c6585-0929-4713-962c-2306f8dcf1f2/turing-proposal-Alan-LR.pdf?lang=en-US
- Turing Archive ACE index: https://www.alanturing.net/turing_archive/archive/index/aceindex.html