Project completeness

Overview
Completeness chart
Key

Overview

The primary goal for the pylons section of this site is to visually illustrate every standard UK tower type by way of outline diagrams. Some non-standard types are included but many will not be, especially the more ad-hoc towers.

For 132 kV and above, this site contains at least the majority of the standard tower series that have ever existed, although not all are fully illustrated or even illustrated at all.

For 33 and 66 kV, the tower series listed below are only those for which it has been possible to assign some kind of a name. More series are known to exist but no means is yet available to name them.

Completeness chart

See the key below the chart for the details of each of the columns.

Designation	Source	Coverage	Drawings needed	Data needed	Identity	Notes	FAO
33 and 66 kV (well-defined types)
Hebden Bridge–Elland	—	None	All	C, S, D, A	Mfr. contract
Milliken L134	GA/ED	Fair	Transposition	C, V	Mfr. contract		SPEN
Milliken E102 single circuit	GA/ED	Good	Earthing arms, lower angle GPO crossing if they existed	C	Mfr. contract		UKPN
Milliken E102 double circuit	None	None	All	C	Mfr. contract	Believed to exist, but formal connection between known towers and E102 is yet to be made	UKPN
Milliken T163	GA/ED	Poor	All except D3 and D10	C, V	Mfr. contract
Milliken T169	—	None	All	C, S, D, A	Mfr. contract		NIE Networks
SEE SL2	GA/ED	Poor	All except D60	C, V	Contract		UKPN
Milliken K721	Various	Poor	All	C	Mfr. contract		NPG
SEE SL3(b)	GA/ED	Poor	S3, S20, ST, GPO crossing, terminal	C, V	Contract		UKPN
SEE SL4	GA/ED	Poor	Line, D30, S60, ST	C, V	Contract		UKPN
J L Eve C15 0.1	GA/ED	Poor	D60, DL, DT		Mfr. drawings
J L Eve C15 0.15	Various	Fair	D60, DL, DT		Mfr. drawings
Pontypridd	—	None	All	C, V, S, D, A			NGED
Milliken E177 single circuit	Street View	Poor	All	C	Mfr. contract		SSEN South
Milliken E177 double circuit	GA/ED	Good	D60 GPO crossing, D90, D90 GPO crossing
Milliken E177 four circuit	Other	Poor	All
SEE SL6	Street View	Bad	All	C, D	Contract		UKPN
SEE SL8	GA/ED	Poor	All except terminal	C	Contract		UKPN
Blaw Knox K1373	GA/ED	Complete		C
Blaw Knox K4611	GA/ED	Fair		C		Update and completion from GA/ED queued
NWE SL4	GA/ED	Fair	Terminal, GPO crossing	C, V	Contract
J L Eve C333	GA/ED	Fair	Terminal	C, A	Mfr. drawing range
Abergavenny and Cwmbran	Street View	Fair	All	C, V	Location-based moniker		NGED
Preston Corporation	Street View	Fair	All	C, D	Customer	Double earthwire barely covered (now all demolished or downgraded)	ENWL
Coventry	—	None	All	C, V, S, D, A			NGED
Riley and Neate H99	GA/ED	Good	72° towers		Mfr. contract		NPG
Blaw Knox K9906	GA/ED	Complete	—	C	Mfr. contract
L4(m) 66	GA/ED	Fair	D60, production terminal types; all GA&ED		Official		NPG
110 kV (Northern Ireland)
Blaw Knox K1641	Various	Good	S30, S60, S90	C	Unknown	SCT appears to be a standard 132 kV type …	NIE Networks
Belfast four-circuit	—	None	All	C, D	Route-based moniker		NIE Networks
132 kV
CS-PL1	Other	Fair	All		Problematic	No trace so far of a B2 type (equivalent to D10)
SS-PL1	Various	Good	D30, S30, S60, S90, ST; 6 foot peak ST (e.g. Glenlee)		Problematic	This is a mish-mash of separate, related series
Stafford–Wolverhampton S2	Street View	Good	S2		?	Substitute S2 tower for CE PL1 used between Stafford and Wolverhampton	NGED
NWE PL2	GA/ED	Poor	Towers 3, B15, B16, F6, F7, 16–20, 112–113, 217, J3J4		Contract
Rannoch–Abernethy	Street View	Good	All	C, D, A	Route-based moniker		SSEN
SEE PL1a/MEE PL1	Various	Good	All except D2, DT, S2; DX especially		Contract		UKPN
SEE PL1a/MEE PL1	Various	Good	All except D2, DT, S2; DX especially		Contract		NPG
SEE PL1(b)	Various	Good	S30, S60, terminal towers		Contract		UKPN
Spey Valley	GA/ED	Fair	Short peaks; spires; 132/132 transposition		Contract	Name taken from the drawings	SSEN
CE PL3	Various	Poor	All except D2, D30 and DD30		Contract		NGED
PL4/WGR double circuit	Tower Bible	Good	Terminal towers		Convention	Redraw from GA/ED queued
PL4/WGR single circuit	Various	Poor	All except S60 SEW		Convention	Also known as PL9/SWE PL9, Blaw Knox K5297
Lydney	Photos	Poor	All	S, D, A	Location-based moniker	Nothing known about the reason for this line or its identity	NGED
PL7	Tower Bible	Good	Terminal tower adaptations		Convention	Redraw from GA/ED queued	UKPN
Blaw Knox K5735	GA/ED	Poor	Single earthwire types; terminal	C	Mfr. drawings		ENWL
PL16 (double circuit only)	GA/ED	Good	Gantries, DC types		Problematic
Blaw Knox K1201	GA/ED	Good	SS10, SS60, S90, SS90		Contested	PL16/STL1 naming dispute	SSEN
Blaw Knox K1420	GA/ED	Good	S2; wood pole intermediates		Contested	PL16/STL1 naming dispute	SSEN
J L Eve C534 (L16)	GA/ED	Good	—		Mfr. contract
J L Eve C670	GA/ED	Complete	—		Mfr. contract
J L Eve C772	Other	Poor	D2, D10, D30, D60		Mfr. contract	PL16/STL1 naming dispute	SSEN
Inveraray–Taynuilt	GA/ED	Good	Loch Awe crossing tower dimensions		Route-based moniker		SSEN
J L Eve C1415	GA/ED	Good	DT extended top crossarms		Contested	Drawn from C1824; PL16/STL1 naming dispute	SSEN
Quoich–Broadford	GA/ED	Complete	—		Route-based moniker
L7	Key diagrams †	Good	—		Official	Redraw from GA/ED queued
L4(m)	Key diagrams †	Good	—		Official	Redraw from GA/ED stalled due to major source material errors
275 and 400 kV
L34	Mixed	Good	All		Contract
L66 / L66/89 / L1	Key diagrams	Complete	—		Contract	Redraw from GA/ED queued
L2	Various	Good	All		Official
L3, Blaw Knox	Various	Good	All		Official
L3, J L Eve	GA/ED	Good	ST, any gantries		Official
Blaw Knox T1521	GA/ED	Unknown	All		Mfr. contract	Scope of contract unknown	SSEN
Blaw Knox T1648	GA/ED	Unknown	All		Mfr. contract	Scope of contract unknown	SSEN
Blaw Knox T2175	Key diagrams	Good	—		Mfr. contract	GA&ED believed to be lost forever
L6, Balfour Beatty	Key diagrams †	Good	All		Official
L6, BICC	Key diagrams †	Good	All		Official
L6, Blaw-Knox	Key diagrams †	Good	All		Official
L6, J L Eve	Key diagrams	Fair	All		Official
L6(c)	Key diagrams	Good	All		Official
L6(m)	Key diagrams †	Fair	All		Official
L8	Key diagrams †	Good	All		Official
L8(c) Modified	Key diagrams †	Unknown	All		Official	L8 single circuit
L8 R	Other material	Poor	All		Official	L8 275 kV–only reduced height
L9	(GA/ED)	(Complete)	—		Official	L9(c) LD redraw from GA/ED failed due to major source material errors
L12	Other	Good	?		Official	Is there any visual difference with L12X?
L12 low-height	Other	Good	All		Official
Coylton–Auchencrosh	Key diagrams	Complete	—		Route-based moniker
L13	Public material	Poor	All		Official
SSE400	Key diagrams	Complete	Lower-strength D		Official		SSEN
C-IVI-1	Various	Good	—		Official	Under construction
AS4	Key diagrams	Complete			Official	Not yet constructed

Key

Designation

The designation chosen for this site; these range from official to completely ad-hoc.

Source

All the diagrams on the site should be traced from general arrangement and erection diagrams, but in many instances, less accurate sources have been used.

GA/ED: Diagrams traced from official general arrangement and/or erection diagrams. Older GA/ED drawings are prone to exaggerated dimensions for various tower components, requiring the diagrams on this site to be adjusted according to visual sources to be closer to the actual design. This is particularly problematic with tower peaks, especially Milliken PL1 suites.
Key diagrams: Official drawings in outline form, often known as key diagrams, outline diagrams or key erection diagrams. These are fairly accurate but may contain errors, especially where marked †.
Tower Bible: Either Jon Bruford’s original [Tower Bible] or Matt’s enhanced version (less incomplete than the original). The source material is in wireframe form only and (especially where marked †) inaccurate.
Street View: Google Street View, owing to not having neither unlimited time and money nor a teleporter. Tracing from Street View introduces various errors and does not allow the tower sizes to be determined.
Photos: Photographs only
Various: Multiple source types
Other: Other material, e.g. National Grid or SSEN publicly-available stakeholder material; these can be considerably inaccurate (especially where marked †).

Coverage

Coverage refers exclusively to the completeness level of a tower suite, regardless of the quality of source material. Coverage is relative to an estimate of what tower types exist within the suite, as this information is seldom available.

Entries in brackets (parentheses) denote the coverage status once all queued material has been processed.

None: No diagrams attempted due to lack of material and size data
Poor: Only a small portion of the series has been covered due to lack of material
Fair: Most tower types are illustrated but one or more important types remain missing
Good: All standard types are covered; gaps may still exist for less-common types such as gantries or crossing towers
Complete: Believed to be complete
Unknown: Insufficient data to determine what the tower suite contains

Drawings needed

This column indicates the towers for which drawings are needed, preferably general arrangement and erection diagrams. For towers where the source is already noted as an outline source (key diagrams, Tower Bible etc), then a general arrangement or erection diagram is needed for greater accuracy. For tower types where the source is only visual (e.g. Street View) or where there is no source at all, then any reasonable material is acceptable, as lower-accuracy material can be used as a stop-gap.

Needed less

Needed

Needed more

Work done

Data needed

Abbreviated in the table to save space:

C: Design conductors (phase and earthwire), preferably including the modern variant codename, e.g. 0.175^□″ SCA (now 175 mm² Lynx ACSR); Lynx is assumed for all 132 kV types where not specified on the drawings
V: Design voltage
S: The contract (such as SEE SL1) for which the towers were designed
D: Tower type designations
A: Age of design

Photography coverage

: No photographs at all. This normally indicates a tower type that is out of travel range, but it can also be due to the extinction of a tower type (for which licensable historic photos may exist).
: Minimal coverage, often just the header image.
: Partial coverage: some tower types remain missing.
: Good coverage; one or more types may still be missing but there is a good visual depiction of the series.

Identity

Per industry convention, the identity should represent the oldest contract for which the towers were designed. Determining this original contract is often impossible.

Official: The designation used on this site is the official designation for the tower series in question.
Mfr. contract: The series is designated per the manufacturer’s contract number (Milliken and Blaw Knox). Prior to the 1950s there is no guarantee that the same towers do not exist in a previous contract.
Mfr. drawing range: The series is designated per the manufacturer’s drawing number range (J L Eve) — the same tower suite may have multiple sets of drawings and there is no guarantee that the drawing set used for this site is the original set for the tower series in question.
Contract: The series is designated per the contract (e.g. SEE SL4, CE PL3) for which the drawings are understood or assumed to have been produced. The same towers can exist in multiple contracts and there is no guarantee that the same tower designs don’t also exist in an earlier contract.
Convention: Conventional name within the industry.
Route-based moniker: The tower suite has been assigned a name within this site based on the endpoints of the route due to lack of source material; for tower suites specific to a single line, these names will be retained for ease of use compared to memorising manufacturer contract numbers, unless there is good evidence of a more appropriate name.
Location-based moniker: As above, but where the original routes are not known due to partial demolition of the original line.
Problematic: One or more problems exist with determining the identity, for example industry abuse (as with “PL16”) or where more work is needed for clarity (K1373 and K4611 appear to be overlapping contracts).
Contested: The identity of the tower suite is disputed