Get the current price and information for O Steam Articulated Key Model Imports Challenger Union Pacific 4-6-6-4 by Key Model Imports (KEY) Call 352-292-4116 Mon-Thur 9am-4pm EST Model Search:Premier 4-6-6-4 Challenger Steam Locomotive Compatibility This engine will operate on any traditional O-72 Gauge track system, including M.T.H.’s RealTrax® or ScaleTrax™ or traditional tubular track. It is also compatible with most standard AC transformers. (See pag e 23 for a complete list of compatible transformers and wiring instructions.) Union Pacific had 10 two-tone gray 4-6-6-4 Challengers. These 10 locomotives were part of a group of 13 oil-burning 4-6-6-4 Challengers that UP re-assigned beginning in December 1946 from Southern California on UP's South-Central District, to the Northwestern District. The new service was between Seattle and Portland, and along the Columbia ...Bowser - HO - Steam Loco Kits Union Pacific Challenger 4-6-6-4. History: The 4-6-6-4 class, original Challenger was designed by Otto Jabelmann of the Union Pacific and first built by Alco for UP. Approximately 230 Challengers were built nearly alike, differing only in their steam pressure, cylinders, and boilers. The last two Flyer steamers I tested in CTT were the plastic 0-6-0T and the Union Pacific 4-8-4 in the Feb and Sept 2007 issues. After running the new Challenger, I’d say it is time to close the door on old Flyer and embrace a new era of gear that isn’t stuck in 1962 regarding design or performance.The introduction of “super-power” steam technology in the 1920’s, however, enabled builders to create freight locomotives that combined speed and power. Perhaps the zenith of the fast freight engine was the 4-6-6-4 Challenger, first conceived by the Union Pacific Railroad and American Locomotive Works in the mid-1930s.These pictures, captioned the last challenger were taken June 7 1953. They show engine 1211 leading yet another westbound train out of Cumberland and up Sandpatch with mid-train helper Decapod 1130 and shoving on the rear is 4-8-4 number 1404. Only 1210 and 1211 remained on the roster that June. When talking to WM men there seemed to be only 2 ...See full list on american-rails.com The resulting machine was a winner. UP tested the new 4-6-6-4 engine on a section of track in Utah over the Wahsatch Range. The engineer commented that would be a challenge for any locomotive, and the name stuck. UP officially called the machine the Challenger. A total of 252 Challengers were built between 1935 and 1943. UP received the most, 105.The name Challenger was given to steam locomotives with a 4-6-6-4 wheel arrangement. This means that they have four wheels in the leading "pilot" truck, which helps guide the locomotive into curves; two sets of six "driving" wheels, and finally, four "trailing" wheels, which support the rear of the engine and its massive firebox.6.4L HEMI Info. Chrysler introduced a production version of the crate 392 Hemi engine in the 2011 Dodge Challenger SRT8. It was a 6.4-liter V8 naturally aspirated engine, based on the architecture of the 5.7L Hemi V8. In 2014, a revised version of the 6.4L Hemi SRT became available for the Ram 2500/3500 trucks and Ram 3500, 4500, and 5500 Cab ...The first Challengers were conceived in 1936 as fast freight engines to replace the Union Pacific's fleet of three-cylinder 4-12-2 locomotives. With an extra center cylinder for added power and a top speed of 45 mph, the 4-12-2s had been successful freight engines when built in 1926.All of the tenders were recycled from other (earlier) models - Long Distance Coal from the 4-6-2 Heavy Pacific, Vanderbilt from the 2-8-2 Heavy Mikado, and Centipede from the 4-8-8-4 Big Boy. The chassis is all-metal and quite hefty. As mentioned previously, the motor is an open-sided Mabuchi (3-pole / skew-wound).Jul 27, 2023 · Get the current price and information for O Steam Articulated Key Model Imports Challenger Union Pacific 4-6-6-4 by Key Model Imports (KEY) Call 352-292-4116 Mon-Thur 9am-4pm EST Model Search: For those looking at really making their Dodge Challenger or Charger scream, a 6.4 HEMI supercharger is the way to go. The current production 392 HEMI makes 485 hp and 475 lb-ft, while the crate version makes 525 hp and 510 lb-ft. Adding a supercharger can easily add 100+whp to your engine without breaking a sweat.Lionel Union Pacific 4-6-6-4 Challenger equipped with QSI Quantum DCC Sound and most recent software/upgrade chip.Features metal die cast frame & superstruct...The last two Flyer steamers I tested in CTT were the plastic 0-6-0T and the Union Pacific 4-8-4 in the Feb and Sept 2007 issues. After running the new Challenger, I’d say it is time to close the door on old Flyer and embrace a new era of gear that isn’t stuck in 1962 regarding design or performance.Jan 11, 2021 · 6.4 HEMI Common Problems Summary. The 6.4 HEMI first began its life as a crate engine under the name 392 HEMI. In 2011, FCA began using the 392 Apache in production models beginning with the Dodge Challenger SRT8. Since then the engine found its way into many flagship performance models and trucks. Introducing Broadway Limited Imports' newest addition to our line of N Scale steam locomotives, the Union Pacific Late Challenger.Between 1936 and 1944, the American Locomotive Company (ALCO) constructed a total of 105 Challengers in five classes for the 6.4L HEMI Info. Chrysler introduced a production version of the crate 392 Hemi engine in the 2011 Dodge Challenger SRT8. It was a 6.4-liter V8 naturally aspirated engine, based on the architecture of the 5.7L Hemi V8. In 2014, a revised version of the 6.4L Hemi SRT became available for the Ram 2500/3500 trucks and Ram 3500, 4500, and 5500 Cab ... The Northern Pacific ordered 21 "Challengers" from the American Locomotive Company in 1936 and took delivery of them during 1936 and 1937. These 4-6-6-4s were designated Class Z-6 and were assigned road numbers 5100 through 5120. They had four 23 x 32 cylinders, 69" drivers, a 250 psi boiler pressure, exerted 104,500 lbs of tractive effort and ...In Whyte notation, a 4-6-6-4 is a railroad steam locomotive that has four leading wheels followed by six coupled driving wheels, a second set of six driving wheels and four trailing wheels. 4-6-6-4's are commonly known as Challengers. Union Pacific Challenger No. 3985 is an example of a 4-6-6-4 locomotive. Get the best deals for 4-6-6-4 challenger at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!JLC Clinchfield TMCC 4-6-6-4 Challenger #673 (TMCC) Back by popular demand, the Joshua Lionel Cowen Series Challenger is sure to thrill and amaze you. Built with more detail than anything previously attempted in O-Gauge die-cast, this locomotive is the piece de resistance of any collection. Get the best deals for lionel 4-6-6-4 challenger at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!In Whyte notation, a 4-6-6-4 is a railroad steam locomotive that has four leading wheels followed by six coupled driving wheels, a second set of six driving wheels and four trailing wheels. 4-6-6-4's are commonly known as Challengers.The name Challenger was given to steam locomotives with a 4-6-6-4 wheel arrangement. This means that they have four wheels in the leading "pilot" truck, which helps guide the locomotive into curves; two sets of six "driving" wheels, and finally, four "trailing" wheels, which support the rear of the engine and its massive firebox.Broadway Limited Imports -- 4-6-6-4 Challenger Late, Smoke Lifters, Oil Tender, Sound, DCC, Smoke - Paragon 3 -- Union Pacific 3985 (Excursion Scheme, black, graphite) -- This 4-6-6-4 Challenger features full Paragon3 sound and DCC for realistic sound and The Union Pacific Railroad took delivery of the very first locomotive with the 4-6-6-4 wheel arrangement in 1936 when it received 15 of them from the American Locomotive Company. These newly named "Challengers" were designated Class CSA-1. In 1937, another 25 ALCO-built "Challengers" were added to the roster. This group, designated Class CSA-2 ...Jan 11, 2021 · 6.4 HEMI Common Problems Summary. The 6.4 HEMI first began its life as a crate engine under the name 392 HEMI. In 2011, FCA began using the 392 Apache in production models beginning with the Dodge Challenger SRT8. Since then the engine found its way into many flagship performance models and trucks. This BLI model is of the Class CSA-2 Challenger, commonly called an “early challenger”. Our models have a post-1947 appearance, after the locomotives were renumbered from 3900 to 3800 series. We are offering three locomotive variations: four road numbers with the as-delivered front engine, four road numbers with a rebuilt front engine, and ...N SCALE UNION PACIFIC CHALLENGER 4-6-6-4 BRASS MODEL KEY IMPORTS Cab Forward. Pre-Owned. $1,399.99. or Best Offer. +$16.00 shipping. Free returns. Sponsored.8 4-6-6-4 Challenger Steam Locomotive Using DCS With DC Power M.T.H.’s revolutionary Digital Command System, or DCS, allows users to control their RailKing One-Gauge locomotives in a command control environment. User’s can remotely access hundreds of features inside each RailKing One-Gauge locomotive with the wireless remote control.In Whyte notation, a 4-6-6-4 is a railroad steam locomotive that has four leading wheels followed by six coupled driving wheels, a second set of six driving wheels and four trailing wheels. 4-6-6-4's are commonly known as Challengers. [1] A similar wheel arrangement exists for Garratt locomotives, but is referred to as 4-6-0+0-6-4. The introduction of “super-power” steam technology in the 1920’s, however, enabled builders to create freight locomotives that combined speed and power. Perhaps the zenith of the fast freight engine was the 4-6-6-4 Challenger, first conceived by the Union Pacific Railroad and American Locomotive Works in the mid-1930s. the tender drawbar pin. Now join the 6-pin connectors so they are properly seated. If the ground spring on the drawbar does not have good contact with the tender drawbar pin, the engine will have erratic or no operation. Premier 4-6-6-4 Challenger Steam Engine 6The Great Northern Railway bought two 4-6-6-4s from its subsidiary, the Spokane, Portland & Seattle Railroad These two ALCO-built, former SP&S road numbers 903 and 904, were designated Class Z-6 and were given road numbers 4000 and 4001 on the Great Northern. They had four 23 x 32 cylinders, 69" drivers, a boiler pressure of 250 psi, a tractive ...Union Pacific had 10 two-tone gray 4-6-6-4 Challengers. These 10 locomotives were part of a group of 13 oil-burning 4-6-6-4 Challengers that UP re-assigned beginning in December 1946 from Southern California on UP's South-Central District, to the Northwestern District. The new service was between Seattle and Portland, and along the Columbia ...Union Pacific had 10 two-tone gray 4-6-6-4 Challengers. These 10 locomotives were part of a group of 13 oil-burning 4-6-6-4 Challengers that UP re-assigned beginning in December 1946 from Southern California on UP's South-Central District, to the Northwestern District. The new service was between Seattle and Portland, and along the Columbia ...Introducing Broadway Limited Imports' newest addition to our line of N Scale steam locomotives, the Union Pacific Late Challenger.Between 1936 and 1944, the American Locomotive Company (ALCO) constructed a total of 105 Challengers in five classes for theThe Great Northern Railway bought two 4-6-6-4s from its subsidiary, the Spokane, Portland & Seattle Railroad These two ALCO-built, former SP&S road numbers 903 and 904, were designated Class Z-6 and were given road numbers 4000 and 4001 on the Great Northern. They had four 23 x 32 cylinders, 69" drivers, a boiler pressure of 250 psi, a tractive ...The Union Pacific introduced the 4-6-6-4 in 1936 and ended up owning the largest and most famous fleet of Challengers. Designed as freight haulers, they were regularly used in high-speed passenger service. The line’s fleet operated well into the diesel era, with the last Challenger being dropped from the roster in 1962.This BLI model is of the Class CSA-2 Challenger, commonly called an “early challenger”. Our models have a post-1947 appearance, after the locomotives were renumbered from 3900 to 3800 series. We are offering three locomotive variations: four road numbers with the as-delivered front engine, four road numbers with a rebuilt front engine, and ... 451 N Nova Road, Daytona Beach, FL. 2021 Dodge Challenger R/T Scat Pack Widebody. Exterior Color: Triple Nickel Clear Coat. Interior Color: Black. Engine: 6.4L V8 Gas (485hp) Transmission:This video contains products that were purchased, provided or discounted. In most cases, products are a mix of discounted and otherwise purchased. In addit...These earliest Challengers, some 60 in total, proved their worth on the steep grades of the Wasatch Mountains, showing clearly that the big brute 4-6-6-4 engines had more power and speed than their predecessors. In 1943, twenty five additional ALCO Challengers arrived at the Union Pacific Railroad. These locomotives were initially designed as ...The 4-6-6-4 Challenger first appeared on U This is an MTH 70-3016-1 Union Pacific 4-6-6-4 Challenger Steam Engine w/Proto-Sound 2.0, (Yellow Stripes) Cab No. 3980. In the midst of the Great Depression, Union Pacific designed and asked ALCO to build the best high-speed simple articulated engines to grace American rails. The 4-6-6-4 Challenger first appeared on U This is an MTH 70-3016-1 Union Pacific 4-6-6-4 Challenger Steam Engine w/Proto-Sound 2.0, (Yellow Stripes) Cab No. 3980. In the midst of the Great Depression, Union Pacific designed and asked ALCO to build the best high-speed simple articulated engines to grace American rails. Get the best deals for lionel 4-6-6-4 challenger at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items! The Denver & Rio Grande Western Railroad bought ten 4-6-6-4s from the Baldwin Locomotive Works in 1937 to speed up its freight trains. These locomotives were designated Class L-105 and were given road numbers 3700 through 3709. They had four 23 x 32 cylinders, 70" drivers, a boiler pressure of 280 psi, a tractive effort of 105,000 lbs and ...Number of 4-6-6-4 "Challenger" Type Locomotives Built by Year (by Richard Duley) Railroads that used 4-6-6-4 "Challenger" Locomotives in the USA (data provided by Steve Llanso of Sweat House Media) Carolina, Clinchfield & Ohio Delaware & Hudson Denver & Rio Grande Western Great Northern Northern Pacific Spokane, Portland & Seattle Union Pacific The Northern Pacific ordered 21 "Challengers" from the American Locomotive Company in 1936 and took delivery of them during 1936 and 1937. These 4-6-6-4s were designated Class Z-6 and were assigned road numbers 5100 through 5120. They had four 23 x 32 cylinders, 69" drivers, a 250 psi boiler pressure, exerted 104,500 lbs of tractive effort and ...Reviewing my recently purchased AHM Rivarossi - ALCO Schenectady 4-6-6-4 "Challenger" road number 1506 with the Delaware & Hudson.The model is a AHM Rivaros...In order to mate the connectors of the drawbar and the tender, place the engine and the tender on the track. Position the tender over the drawbar connector and insert the drawbar pin on the swivel connector into the hole in the drawbar. M.T.H. HO 4-6-6-4 Challenger Steam Engine... While a large number of Challengers found service out West, 4-6-6-4s had colorful careers in the East, too. In 1942, eight Challengers were initially ordered by Clinchfield, and after the war they received four additional units. The Clinchfield Railroad also purchased six final Challenger locomotives in 1947 that the D&RGW had rejected a few ...Unclebob said: I've had 4 scat packs and 2 5.7's. (I get bored lol) The 5.7 is arguably a better motor imo, although the 6.4 is faster. You really would be happy with either, as the 5.7 isn't a slouch. (The 5.7 stock exhaust sounds better too) If my choice was between a stripped down 5.7 vs. a stripped 6.4, I'd go 6.4.Bowser - HO - Steam Loco Kits Union Pacific Challenger 4-6-6-4. History: The 4-6-6-4 class, original Challenger was designed by Otto Jabelmann of the Union Pacific and first built by Alco for UP. Approximately 230 Challengers were built nearly alike, differing only in their steam pressure, cylinders, and boilers. This video contains products that were purchased, provided or discounted. In most cases, products are a mix of discounted and otherwise purchased. In addit...Locking your locomotive into a single operational state 4 Your locomotive’s Odyssey™ System speed control 5 Using your tender-mounted ElectroCoupler in the non-Command environment 6 Your locomotive’s RailSounds system—the basics 7 Experiencing the range of your locomotive’s RailSounds system 8 Notes on RailSounds 8While a large number of Challengers found service out West, 4-6-6-4s had colorful careers in the East, too. In 1942, eight Challengers were initially ordered by Clinchfield, and after the war they received four additional units. The Clinchfield Railroad also purchased six final Challenger locomotives in 1947 that the D&RGW had rejected a few ...The Northern Pacific ordered 21 "Challengers" from the American Locomotive Company in 1936 and took delivery of them during 1936 and 1937. These 4-6-6-4s were designated Class Z-6 and were assigned road numbers 5100 through 5120. They had four 23 x 32 cylinders, 69" drivers, a 250 psi boiler pressure, exerted 104,500 lbs of tractive effort and ...Reviewing my recently purchased AHM Rivarossi - ALCO Schenectady 4-6-6-4 "Challenger" road number 1506 with the Delaware & Hudson.The model is a AHM Rivaros...Challenger marks Lionel’s return to HO. “Challenger” is one of the more dramatic names given to any steam locomotive wheel arrangement, and the new HO scale 4-6-6-4 from Lionel lives up to that moniker. It’s a well-executed model of a well-known group of locomotives, made more famous because one of them still steams.These pictures, captioned the last challenger were taken June 7 1953. They show engine 1211 leading yet another westbound train out of Cumberland and up Sandpatch with mid-train helper Decapod 1130 and shoving on the rear is 4-8-4 number 1404. Only 1210 and 1211 remained on the roster that June. When talking to WM men there seemed to be only 2 ...In Whyte notation, a 4-6-6-4 is a railroad steam locomotive that has four leading wheels followed by six coupled driving wheels, a second set of six driving wheels and four trailing wheels. 4-6-6-4's are commonly known as Challengers.Union Pacific LEGACY 4-6-6-4 Challenger #3985 (BLACK) Challengers for the first time in American Flyer S Gauge. With the advent of diminished locomotive production due to World War II demands and restrictions, many western railroads were hungry for top performing and even more powerful steamers.Introducing Broadway Limited Imports' newest addition to our line of N Scale steam locomotives, the Union Pacific Late Challenger.Between 1936 and 1944, the American Locomotive Company (ALCO) constructed a total of 105 Challengers in five classes for thePremier 4-6-6-4 Challenger Steam Locomotive Compatibility This engine will operate on any traditional O-72 Gauge track system, including M.T.H.’s RealTrax® or ScaleTrax™ or traditional tubular track. It is also compatible with most standard AC transformers. (See pag e 23 for a complete list of compatible transformers and wiring instructions.)O GAUGE PREMIER LINE 4-6-6-4 CHALLENGER BY MTH Price: Features: O-72 operation, die-cast metal construction, can-style motor, ProtoSound 2.0, coil coupler on tender. Pros: Visually stunning, clever new wireless drawbar, superb performance. Cons: Some of the piping and details can be bent by clumsy fingers. Made in the Republic of Korea for MTH ...We offer you choices for building your own 7 1⁄4 - 7 1⁄2 inch gauge live steam model of the Union Pacific 4-6-6-4 Challenger: Scaled down from original Union Pacific railroad drawings: Ensures high model accuracy. Unique among models: Largest, most powerful and only articulated model on the market. Exceptionally high quality product: Fully ...The introduction of “super-power” steam technology in the 1920’s, however, enabled builders to create freight locomotives that combined speed and power. Perhaps the zenith of the fast freight engine was the 4-6-6-4 Challenger, first conceived by the Union Pacific Railroad and American Locomotive Works in the mid-1930s.In Whyte notation, a 4-6-6-4 is a railroad steam locomotive that has four leading wheels followed by six coupled driving wheels, a second set of six driving wheels and four trailing wheels. 4-6-6-4's are commonly known as Challengers.While a large number of Challengers found service out West, 4-6-6-4s had colorful careers in the East, too. In 1942, eight Challengers were initially ordered by Clinchfield, and after the war they received four additional units. The Clinchfield Railroad also purchased six final Challenger locomotives in 1947 that the D&RGW had rejected a few ...The two ALCO-built 4-6-6-4s received in 1944 were also oil burners and were designated Class Z-8 and given road numbers 910 and 911. These locomotives had (4) 23 x 32 cylinders, 70" drivers, a 260 psi boiler pressure, a tractive effort of 107,000 lbs and weighed 639,000 pounds. The eight SP&S "Challengers" were scrapped in 1960.Jan 16, 2017 · Like UP’s earlier 4-6-6-4 Challenger, the Big Boy was articulated to help it negotiate curves and turnouts. On the prototype, the front engine pivoted under the smokebox. On the model, both engines pivot, which is necessary to handle 18″ radius curves, but it creates unrealistic cab overhang. sc e2 bi polar sc usra 0-6-0 rk fef northern rk hudson hiawatha sc nh l5 4-6-4 rk aero train rk usra y6b sc wm challenger rk ese sc c&nw e-4 sc gp-30 sc russian dacapod sc z-6 challenger rk wabash hudson sc orient express sc gp-9 sc gg1 sc class a rk disney engine in vt sc ese hudson sc e-8 rk usra mallot sc berkshire rk p-47 baldwin sc ...This BLI model is of the Class CSA-2 Challenger, commonly called an “early challenger”. Our models have a post-1947 appearance, after the locomotives were renumbered from 3900 to 3800 series. We are offering three locomotive variations: four road numbers with the as-delivered front engine, four road numbers with a rebuilt front engine, and ... Get the best deals for 4-6-6-4 challenger at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items! RailKing 4-6-6-4 Challenger Steam Engine Set Up There are a few simple steps you must take before operating this RailKing steamer. 1. You should prime the operating smoke unit with smoke fluid before operating. Add 15-20 drops of smoke fluid through the smokestack, then gently blow into the stack to eliminate any air bubbles in the fluid. See ... The name Challenger was given to steam locomotives with a 4-6-6-4 wheel arrangement. This means that they have four wheels in the leading "pilot" truck, which helps guide the locomotive into curves; two sets of six "driving" wheels, and finally, four "trailing" wheels, which support the rear of the engine and its massive firebox.
Union Pacific LEGACY 4-6-6-4 Challenger #3977 (GRAY) Challengers for the first time in American Flyer S Gauge. With the advent of diminished locomotive production due to World War II demands and restrictions, many western railroads were hungry for top performing and even more powerful steamers.. Sampercent27s club gas price elgin il
Lionel Union Pacific 4-6-6-4 Challenger equipped with QSI Quantum DCC Sound and most recent software/upgrade chip.Features metal die cast frame & superstruct...Jul 17, 2023 · Find many great new & used options and get the best deals for AHM Challenger -4-6-6-4 -5113-05- Rio Grande -Minty Box at the best online prices at eBay! Free shipping for many products! Jun 20, 2007 · It combines detail, performance, and a solid sound package with a stealthy tether that makes conventional tethers look old fashioned. O GAUGE PREMIER LINE 4-6-6-4 CHALLENGER BY MTH. Price: $1,399.95 (no. 20-3241-1) Features: O-72 operation, die-cast metal construction, can-style motor, ProtoSound 2.0, coil coupler on tender. Get the best deals for lionel 4-6-6-4 challenger at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!The Union Pacific introduced the 4-6-6-4 in 1936 and ended up owning the largest and most famous fleet of Challengers. Designed as freight haulers, they were regularly used in high-speed passenger service. The line’s fleet operated well into the diesel era, with the last Challenger being dropped from the roster in 1962.Jun 20, 2007 · It combines detail, performance, and a solid sound package with a stealthy tether that makes conventional tethers look old fashioned. O GAUGE PREMIER LINE 4-6-6-4 CHALLENGER BY MTH. Price: $1,399.95 (no. 20-3241-1) Features: O-72 operation, die-cast metal construction, can-style motor, ProtoSound 2.0, coil coupler on tender. Introducing Broadway Limited Imports' newest addition to our line of N Scale steam locomotives, the Union Pacific Late Challenger.Between 1936 and 1944, the American Locomotive Company (ALCO) constructed a total of 105 Challengers in five classes for theThe 4-6-6-4 was one of the most technologically advanced of its kind with advancements that allowed for both high horsepower and efficient operations. Sadly, however, like the Yellowstones the Challengers had an extremely short lifespan. Upon delivery of the UP’s first Challenger during the mid-1930s all were scrapped in short order ...the tender drawbar pin. Now join the 6-pin connectors so they are properly seated. If the ground spring on the drawbar does not have good contact with the tender drawbar pin, the engine will have erratic or no operation. Premier 4-6-6-4 Challenger Steam Engine 6Jan 16, 2017 · Like UP’s earlier 4-6-6-4 Challenger, the Big Boy was articulated to help it negotiate curves and turnouts. On the prototype, the front engine pivoted under the smokebox. On the model, both engines pivot, which is necessary to handle 18″ radius curves, but it creates unrealistic cab overhang. The Union Pacific Railroad took delivery of the very first locomotive with the 4-6-6-4 wheel arrangement in 1936 when it received 15 of them from the American Locomotive Company. These newly named "Challengers" were designated Class CSA-1. In 1937, another 25 ALCO-built "Challengers" were added to the roster. This group, designated Class CSA-2 ... .