FROM THE BACKCOUNTRY

Let ’s f ind your per fect ride.

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COMPILED BY JERED KORFHAGE JERED.KORFHAGE@FOURWHEELER.COM

August 1-7

What: Sierra Fest Where: Georgetown, California Hosted by: North American XJ Association Info: naxja.org

August 2-4

What: Rimrocker Trail Adventure Where: Montrose, Colorado Hosted by: Off-Road Safety Academy Info: discoveroffroading.com

August 2-4

What: UTV Con’Quest on the Rubicon Trail Where: Georgetown, California Hosted by: Jeepers Jamboree Info: jeepersjamboree.com

August 5-7

What: Carlisle Truck Nationals Where: Carlisle, Pennsylvania Hosted by: Carlisle Events Info: carlisleevents.com

August 5-7

What: Great American Crawl Where: Gales Creek, Oregon Hosted by: Mickey Thompson Tires & Rockstar Performance Garage Info: mickeythompsontires.com

August 5-7

What: Jeepers Jamboree Where: Georgetown, California Hosted by: Jeepers Jamboree Info: jeepersjamboree.com

August 5-7

What: Trucks Gone Wild Where: Livermore, Maine Hosted by: Barnyard All Terrain Info: trucksgonewild.com

August 6

What: Combine Demolition Derby Where: Lancaster, Pennsylvania Hosted by: Buck Motorsports Park Info: buckmotorsports.com

August 6-7

What: Truck & Jeep Fest Where: San Mateo, California Hosted by: 4 Wheel Parts Info: 4wheelparts.com

August 6-7

What: W.E. Rock Western Series Where: Goldendale, Washington Hosted by: Broken Boulder Farm Info: werocklive.com

August 10-13

What: Vegas to Reno Where: Las Vegas, Nevada Hosted by: Best in the Desert Racing Association Info: bitd.com

August 11-14

What: Mid-Atlantic Overland Festival Where: Huntingdon, Pennsylvania Hosted by: Main Line Overland Info: overlandfestival.com

August 11-14

What: Sierra Trek Where: Truckee, California Hosted by: California Four Wheel Drive Association Info: cal4wheel.com

August 12-13

What: Off-Road and Camping Expo Where: Mormon Lake, Arizona Hosted by: Mormon Lake Lodge Info: campingexpos.com

August 12-14

What: Toledo Jeep Fest Where: Toledo, Ohio Hosted by: City of Toledo Info: toledojeepfest.com

August 12-14

What: Topless for Tatas Where: Pine Grove, Pennsylvania Hosted by: Rausch Creek Off-Road Park Info: rc4x4.org

August 13

What: Lucas Oil East Coast Series Truck and Tractor Pull Where: Lancaster, Pennsylvania Hosted by: Buck Motorsports Park Info: buckmotorsports.com

August 13-14

What: Monster Jam Where: Pensacola, Florida Hosted by: Pensacola Bay Center Info: monsterjam.com

August 15-21

What: Trucks Gone Wild Where: Hale, Michigan Hosted by: Iosco County Fairgrounds Info: trucksgonewild.com

August 17-21

What: Beartooth Adventure Where: Cody, Wyoming Hosted by: Jeep Jamboree USA Info: jeepjamboreeusa.com

August 19-20

What: Savage Off-Road Run Where: Pine Grove, Pennsylvania

Hosted by: Rausch Creek Off-Road Park Info: rc4x4.org

August 19-21

What: Jeep Jam Where: Wilmington, Ohio Hosted by: Muddy Buddys Jeep Wrangler Club Info: jeepjam.org

August 20-21

What: Iron Range Off-Road August Rust Buster Where: Gilbert, Minnesota Hosted by: Iron Range Offroad Info: ironrangeoffroad.com

August 25-27

What: Bighorn Mountains Jeep Jamboree Where: Burgess Junction, Wyoming Hosted by: Jeep Jamboree USA Info: jeepjamboreeusa.com

August 25-27

What: Great Smoky Mountain Jeep Club Invasion Where: Pigeon Forge, Tennessee Hosted by: LeConte Center Info: gsmji.com

August 26-27

What: Scheid Diesel Extravaganza Where: Lyons, Indiana Hosted by: Scheid Diesel Service Company Info: scheiddiesel.com

August 26-28

What: Overland Expo Mountain West Where: Loveland, Colorado Hosted by: The Ranch Info: overlandexpo.com

August 27

What: Monster Trucks and Car Soccer Where: Lancaster, Pennsylvania Hosted by: Buck Motorsports Park Info: buckmotorsports.com

August 27

What: Xrock Extreme Rock Crawling Where: Harrisville, New Hampshire Hosted by: Field and Forest Recreation Area Info: facebook.com/XRockExtreme/

August 27-28

What: SCCA Rally Where: Pine Grove, Pennsylvania Hosted by: Rausch Creek Off-Road Park Info: rc4x4.org

All submissions become the property of Four Wheeler, and we reserve the right to edit them for length, accuracy, and clarity. The editorial department can also be reached through the website at fourwheeler.com. Due to the volume of mail, electronic and otherwise, we cannot respond to every reader, but we do read everything.

BY JERED KORFHAGE JERED.KORFHAGE@FOURWHEELER.COM PHOTOS: FOUR WHEELER ARCHIVES

Visiting the Yuma Proving Ground and the LeTourneau Overland Train

Four Wheeler’s July 1969 issue took us to a special part of the desert where the Devil vacations when he needs some heat. Just north and east of Yuma, Arizona, sits the expansive facility known at the time as the Yuma Proving Ground. Its location makes it favorable for year-round testing with higher-than-average temperatures and some of the lowest precipitation levels around (in 1968, 1.2 inches of rain fell). The Yuma Proving Ground allowed the Army to subject its vehicles to extreme temperatures, deep water crossings, onslaughts of silt to detect dust intrusion and resistance, rocky ledges and punishing washouts to verify structural integrity, and even drops from supply planes.

Among the wheeled and tracked vehicles designed and evaluated at the Yuma Proving Ground, one hulking behemoth caught our attention: the LeTourneau TC-497 Overland Train Mark II. The concept began with logging in mind as a way to transport felled timber away from sites through undeveloped terrain. LeTourneau’s VC-12 Tournatrain was the first iteration, and it was fronted by an engine car fit with a 500hp Cummins VT-12 and a generator. Each car that followed had four wheels and tires, each powered by its own electric motor. A later version of the land locomotive, the VC-22 Sno-Freighter, was used in the arctic regions of Alaska to deliver materials to the Distant Early Warning (DEW) radar stations. This locomotive and its six individually powered cars floated over snowdrifts and crossed rivers with 10-foot-tall pneumatic tires. In addition to moving loads over the frozen tundra, another of LeTourneau’s over-the-snow haulers, the TC-264 Sno-Buggy, gained notoriety for donating its tires and wheels to the Bigfoot 5 monster truck.

Following the success of the previous LeTourneau trackless trains, the United States Army contracted the TC-497 Mark II. This train traded Cummins diesel power for a quartet of gas turbine engines with a better power-toweight ratio, and the ability to expand the train to greater lengths. Four 1,170hp Saturn 10MC engines were spread throughout the train, one in the head car, and the three others dispersed among the trailing cars. In addition to their own electrically driven wheels, all cars were designed to steer individually. Signaling each car to turn at the same point allowed the train to round challenging corners and avoid obstacles. The Mark II was built from aluminum and due to the smaller size of the gas turbine engines, there was room aboard for a crew of six with space for dining and sleeping. The train was 30 feet tall, could carry 150 tons of material, and measured 570 feet long with the ability to extend its payload with additional fuel and cargo cars.

The train was tested at the Yuma Proving Ground and was known as Project OTTER (Overland Train Terrain Evaluation Research). Despite its remarkable capabilities, the train was abandoned with the advent of cargo helicopters. Although most of the overland train was reduced to scrap metal, you can still see its control car at the Yuma Proving Ground. In conjunction with the Army, General Motors has more recently built its Desert Proving Ground within the government test site, allowing for the discreet development and testing of consumer vehicles in the punishing desert environment, far from prying eyes.

If you have a personal account of overland arctic travel or have ever met any of these land trains face to face, please tell us about it by sending a note to editor@fourwheeler.com. Don’t forget to include high-resolution photographs, if you have them. FW

Another of the vehicles that was tested at the Yuma Proving Ground.

FOUR WHEELER (ISSN 0015-9123) August 2022; Vol. 59, No. 8. Copyright © 2022 by Motor Trend Group, LLC. All rights reserved. Published monthly by Motor Trend Group, LLC, 831 South Douglas Street, El Segundo, CA 90245. Periodicals postage paid at Los Angeles, CA, and at additional mailing offices. Single copy price is $6.99. SUBSCRIPTIONS: U.S. APO, FPO and U.S. Possessions $19.97 for 12 isssues. Canada orders add $12.00 per year and international orders add $24.00 per year (for surface mail postage). Payment in advance, U.S. funds only. POSTMASTER: Send all UAA to CFS. (See DMM 707.4.12.5); NON-POSTAL AND MILITARY FACILITIES: Send address corrections to FOUR WHEELER, P.O. Box 37198, Boone, IA 50037.