Gresley's original Cock O The North

I have found this picture of the original Cock O The North from a book printed in the 1930's so hope it dosn't infringe any copyrights.

The P2s were designed to handle the express passenger traffic on the Edinburgh to Aberdeen main line, which is noted for its steep gradients and tight curves. Double-headed Pacifics were prohibited from the line, so the heaviest traffic was usually handled by double-heading two smaller engines. Gresley sought to overcome this need with a Mikado (2-8-2) design with four driving axles for greater adhesion compared to an A3 Pacific. Initial plans were drawn up in 1932, and consisted of a 2-8-2 Mikado design using an A3-type boiler and dual chimney. Whilst the design was still being finalised, two engines were authorised in February 1933. At the end of March, this initial order was reduced to one locomotive. The firebox was lengthened, and a double blastpipe was added. The Kylchap chimney/blastpipe arrangement was chosen, along with an ACFI feed water heater, and smoke deflectors reminiscent of the W1 No 10000 "Hush-Hush".  (LNER Encyclopedia)

Technical Details

The following details are for the P2/3 and P2/2 (streamlined) variants. Mechanically these were the same before streamlining, although No. 2001 "Cock o'the North" was fitted with Lentz R.C. motion with 8" poppet steam and 9" poppet exhaust valves. The total heating surface was also slightly larger (3490.5 sq.ft). This was converted to match the other five P2s in 1938.

Cylinders (x3):		21x26in.
Motion:	Inside:	Gresley conjugated
	Outside:	Walschaerts
	Valves:	9" piston
Boiler:	Max. Diameter:	6ft 5in
	Pressure:	220psi
	Diagram No.:	108
Heating Surface:	Total:	3346.5 sq.ft.
	Firebox:	252.5 sq.ft.
	Tubes:	1281.4 sq.ft. (121x 2.25in)
	Flues:	1063.7 sq.ft. (43x 5.25in)
	Superheater:	748.9 sq.ft. (43x 1.244in)
Grate Area:		50 sq.ft.
Wheels:	Leading:	3ft 2in
	Coupled:	6ft 2in
	Trailing:	3ft 8in
Tractive Effort:	43,462lb	(@ 85% boiler pressure)
Wheelbase:	Total:	64ft 0.9in
	Engine:	37ft 11in
	Tender:	16ft 0in
Weight (full):	Total:	167 tons 10cwt
	Engine:	107 tons 3cwt
	Tender:	60 tons 7cwt
Max. Axle Load:

Once again many thanks to the LNER Encyclopedia for the above tech details http://www.lner.info/locos/P/p2.shtml