---
title: "Do the Lukyanov Water Integrator's dates, purpose, and service history rest on more than one Tier-4 source?"
type: "question"
status: "open"
progress_log: ["2026-07-14: The claim-note's own 2026-07-10 cross-model audit corroborated the 1936 date, PDE/concrete-cracking purpose, export list, and 1980s service across multiple secondary sources (IEEE Xplore doc 8420115 'Lukyanov's Hydraulic Integrator', history-computer.com, Amusing Planet) and corrected a mis-attributed sub-claim — so it no longer rests on a single Tier-4 page. Still no primary or institutional (Polytechnic Museum / Lukyanov's own publications) source read, so the question's evidentiary bar is not met; remains open."]
date_raised: "2026-07-10T00:00:00.000Z"
tags: ["analog-computing","engineering-history","ussr","lukyanov","water-integrator","unverified-source"]
---


The note [[claim-lukyanov-water-integrator-1936-hydraulic-differential-equation-solver]]
rests entirely on the Tier-4 Wikipedia article *Water integrator*. Its
load-bearing specifics are all single-sourced:

- the **1936** build date,
- that it solved **partial differential equations** for **concrete-crack /
  thermal** prediction,
- **export** to China, Poland, Bulgaria, and Czechoslovakia, and
- continued official use **into the 1980s** (canals, railways, rocket
  production).

For an obscure, load-bearing historical entity this clears only the "uncontested
Tier 3–4" bar weakly, so the claim is flagged `[unverified-source]`.

**What would answer it:**
- The Polytechnic Museum (Moscow) holdings/records for Lukyanov's integrator,
  which preserves surviving units.
- Lukyanov's own publications or a Soviet-era engineering history (e.g.
  accounts in the history of analog computing by A.N. Krylov's milieu, or
  Russian secondary histories with citations).
- An English-language scholarly history of hydraulic/analog computation that
  cites primaries rather than repeating the Wikipedia summary.

This also underwrites the independence framing in
[[claim-hydraulic-analog-computers-independently-invented-economics-engineering]]:
confirming Lukyanov's 1936 priority and isolation from the British work is what
makes the convergence genuinely independent rather than tidy. Note stays
`seedling` until a primary or institutional source is read.