Can some NYC expert explain the difference between the Central's class K5, K5a and K5b Pacifics. They're handsome engines who are obvious cousins of the H10 class Mikes and it's easy to see how they led to the Hudsons. Thanks!
While I'm doing some research (just in case Ed is slacking this morning! ) there is some discussion of the K5s in the 'what went before' section of Staufer's 'Thoroughbreds' book on the Hudson's (which you should own if you like Kiefer and late NYC power).
Only one K5 was a NYC engine: 5000 (indicating first of a significant class; compare Woodard's 'super-power' Mikado 8000). All the others went to NYC subsidiaries (Big Four, Michigan Central, P&LE) so were 'west end' engines where higher speeds were expected. The inimitable K6s (which Staufer saw as the direct predecessors of the Hudson design) were also for a subsidiary, the B&A -- the Brooks "design" for smokebox front being one of the great WTF moments in locomotive design.
Oddly steamlocomotive.com is silent on the specific phase differences, so Edson or Staufer's 'NYC Later Power' (which I do not own) may have to be consulted.
I do know some specifics for the two high-speed conversions (K5bs 4915 and 4917 as designated in the 1936 renumbering, which received disc drivers and other improvements as part of their streamlining and assignment to the new Mercury train.) Boiler pressure was increased to 210psi, increasing TE to over 47,000lb with starting booster cut in -- the streamlining's increased weight keeping FA reasonable.
At least one K5b was given a 'Selkirk front end' in the late '40s, so the class was still recognized as important into the Niagara era. 4915 survived in service to 1952, and wasn't scrapped until 1954.
Here is the 'best' of the K5 evolution in Cincinnati, 1949, after the Mercury shroud was removed:
https://www.railarchive.net/nyccollection/images/nyc4915.jpg
For fun, here is what you get when you apply some of the refinements of the K5b to an older K11:
https://8c8bcb47-a-62cb3a1a-s-sites.googlegroups.com/site/bostonalbanyrailroad/home/0-6-0/0-8-0/2-8-0/2-8-2/2-8-4/4-4-0/4-6-0/tank/4-6-2/IMG_0030-001.jpg?attachauth=ANoY7crVH3XuM52Hh4KCoZ7Hnb6_vCWlVEliYNmtWEkgt4jjvTkAGpNeV4QA7B4g7ZagZKNGp0aXyeP4nzc5KXcdAm7J6smiU5jzDpdSTbR5bPnF4cBTyrBvBhOUAit4vfquRq92Pd7qLj9sfS1r-US8P-soVUMuwGhFiw-OxzuqYWYNSGCo3GNaKaXrDCYbtZdqQDGQmUpMZTQULWRj-xo9qkVhRFuJP6iKtq4mEFsUkhibYmS33oKNvWmsKmJdyJrE_9RjSJbYigmy3ZPM-nVGtzJbQCQ8Db9vYph5YEdNVZLSlqkcFlf3Z4c_m7ldxer-MyhhL5JiFwbDYhNzMpAQlxev6gtzPw%3D%3D&attredirects=0
And this is why Staufer considered the K6 and not the K5 to be the immediate processor of the Hudson design:
https://8c8bcb47-a-62cb3a1a-s-sites.googlegroups.com/site/bostonalbanyrailroad/home/0-6-0/0-8-0/2-8-0/2-8-2/2-8-4/4-4-0/4-6-0/tank/4-6-2/IMG_0040.jpg?attachauth=ANoY7cr-y5ZSxc584xmTxMi20MI_bW-8n27Y0PbFEMLvFnzVXY67nucibs3seeGzsv2G5QGo7tJYn48lEP1svN5UGhb4Qu3AxjS2nVdCkBG7djfO7HHaISNZguCAHlBs4qG8TZfYnbHkvyQe_RxEpqTK0FPFAZE9PqlVsfrvuZE2mmnXLxp0mHYPLUjB596hfsb7TryXTacCYJ25spVaLTjTNsci3RarvePwCvqgiQqiBox6AP8DqgGnaSzajIf1huzSDfzlZF-JFyKFNu0e7h_siwCYe7vD4GaQZPcffKl9u1O692W91PONsbQCl_ATWQLYliMabiog&attredirects=0
Those are 75" drivers, as on the B&A J2 Hudsonettes, which makes the bigger boiler look even bigger...
Hello,
Mr. Overmod has provided some good background.
The K5, No. 5000 had reached the maximum permissible axle loading at 303,000 lbs.. As pointed out the K-5a were built for the Michigan Central and had a 25" piston bore as opposed to the 26" on the K-5 (x 28" stroke) and 79" drivers. Only 36 were built. Later, 10 slightly modified (75" drivers, 26 x 26 cylinders) were built for the B&A, designated K-6, and later served on the P&LE after the J-2 Hudsons were delivered.
The smokebox front of the 5000 (re-4925) had the air compressor mounted to the left side of the engine and the door off-set to the right in an odd-looking configuration.
Some K-5a and b's were equipped with Elesco feedwater heaters.
OvermodFor fun, here is what you get when you apply some of the refinements of the K5b to an older K11:
For some good information regarding the K-11s here is a good resource:
https://nycshs.files.wordpress.com/2014/07/pages-from-1981q2the-k-11s.pdf
Compliments of the NYC Historical Society.
Hope that helps, Ed
gmpullmanFor some good information regarding the K-11s here is a good resource: https://nycshs.files.wordpress.com/2014/07/pages-from-1981q2the-k-11s.pdf Compliments of the NYC Historical Society.
Thanks for that. For some reason I thought the K-11 was a fast freight loco. Didn't realize it was so versatile. I have a Bowser K-11 that I really like.
Gary
You're not wrong, they were bought as freight engines but were bumped from that by Class L1 Mohawks (4-8-2's) and ended up being remembered as commuter, local and branch line passenger power (and, yes, they occasionally hauled local freights). Also using Pacifics as fast freighters were DL&W, FEC, ACL, SAL and RF&P - maybe others.