No, 1C is actually Oliver Bulleid - a common misspelling of his surname. 

 
All correctly identified except the extreme bottom right - which is LTC Rolt, Author of "Narrow Boat" and pioneer of the Talyllyn preservation too.



In order reading along from top left:

     1   George Stevenson
     2   Isambard Kingdom Brunel
     3   Oliver Bullied
     4   Heidi Alexander
     5   Mark Hopwood
     6   Werner von Seimens
     7   Nigel Gresley
     8   Richard Trevithick
     9   Daniel Gooch
    10   Jane Jones
    11   Andrew Adonis
    12   Fred H Stephens
    13   Tom Hanks
    14   Richard Beeching
    15   David Shepherd
    16   Magnus Volk
    17   Thomas Tank Engine
    18   Wilbert Vere Awdry
    19   Stephen Joseph
    20   Christian Wolmar
    21   Stephen Byers
    22   Peter Hendy
    23   Richard Branson
    24   Jenny Agutter
    25   Lionel Thomas Caswall Rolt

 

Yes - correct.

 
or even Stephen Joseph?

 

No, it isn't.  Both of the remaining gentlemen are names that I (and many members here) are and will be familiar with, but where the cause is / was so much more than the person, and it strikes me from a quick read that Colin was along similar lines - though before I became quite the activist I am these days.

 

.....famously described himself as a "cab for hire" and was banned from Parliament, as was Geoff Hoon.........what is it about Labour Transport Secretaries that sees so many of them leaving under a cloud?

 
I was looking at 4D and thinking he does look familiar, when it struck me - it's Colin Rosenstiel, isn't it?

 

When I see how many different names some locomotives have been through in their lives, I wonder how Thomas has managed to go unaltered for so many years.

Just two left ... bottom right and just up from there - the ones without the green dots:

 
4B Thomas the tank Engine

 
I K B only real picture of him known to exist he's standing in front of the drag chains that would eventually help with the delayed launch of the Great Eastern.

 
Erm ... I rather think you're getting your rows and columns mixed up: we are all desperately trying to identify the apparently Victorian character in Row 1, Column B. 

 
https://www.wellho.info/pix/wq30.jpg
A2 Sir Nigel Gresley when do I claim my Fiver Tim...

 
4A is Magnus Volk.

 
First face on the last row is former Secretary of State for Transport, Stephen Byers.

 
Row 2, Column A: Werner von Siemens (1816-1892) 

CfN. 

 
Going back to A2, are there some barons building Denmark in the background?

[Edit: The cryptic crossword clue should probably read something like 'Barons building Denmark engineered a railway (8,7,6)']

[Edit: can't count]

 

3C = Tom Hanks

 
Try as I might I can't see Charles Tyson Yerkes.  (OK, I confess that I'm a fan of Jago Hazzard's YouTube videos, in which CTY is frequently mentioned, often along with a mention of his financial 'reputation'.)

 

3B = Colonel Holman Stephens

 

8 to go, including 3 which are so blindingly obvious that I suspect that everyone is leaving them in favour of giving more obscure answers.

I did wonder how long it would take for our new Secretary of State for Transport to be identified.

 
1A: George Stephenson
1D: Heidi Alexander

 
Row 4, Col C:  Rev W Awdry
Row 5, Col D:  Jenny Agutter

 
B4 = Daniel Gooch,
D3 = Rev. Wilbert Awdry

oops.  Mixed up using letters for rows and number for columns! What I meant was:-

2D = Daniel Gooch,
4C = Rev. Wilbert Awdry

 
2D is Sir Daniel Gooch
3A is Lord (Andrew) Adonis

 

Ah - screen width and you are correct then.  See https://www.wellho.info/pix/wq00.jpg for the alternative smartphone layout. 

 
I’m going to bet a fiver that no one gets A2…

 
Oh, there seems to be a different layout on my smartphone screen.  Mark H is in a row on his own.

Sir Nigel is just to the left of Trevithick

 
I have set myself a real challenge in umpiring the answers here, haven't I?

Here is the original graphic with a green dot added on each correctly identified so far to help you check whether a person has been identified; full listing to follow at the end?

 

Slight typo in one of those?  But impressive knowledge of some of the historic faces

 
Ok:
 3E David Shepherd CBE FRSA FGRA
 5B Peter Hendy

 
1C Oliver Bulleid
3B Sir Nigel Gresley

 
2E is Jane Jones
4E is Christian Wolmar

 
Row 3 Column 4: Dr Richard Beeching;
Row 5 Column 3: Richard Branson.

 
Row 1, column 5: our very own Mark Hopwood if I'm not very much mistaken.  His face is fresh in my memory from watching Geoff Marshall's recent YouTube video of the Marlow branch starring Geoff, Mark and the branch's signalling technology.

 
Row 2, column C: Richard Trevithick (13 April 1771 – 22 April 1833) 

There are several others there who I sussed out straight away, but I'll give everyone else a chance first. 

 
Rows 1 to 5, columns A to E.   Maximum 2 each please (today) 2nd December as there's an awful lot of these!  If you're on a small screen, all the images unfolded are at https://www.wellho.info/pix/wq00.jpg