USA — Army testing new JLTVs

ARLINGTON, Va. — The U.S. Army and Marine Corps are using the new­ly built gov­ern­ment pro­to­types of the Joint Light Tac­ti­cal Vehi­cle to refine pro­gram require­ments through rig­or­ous bal­lis­tic, per­for­mance and reli­a­bil­i­ty test­ing.

JLTV
JLTV dri­ving on test track at Aberdeen Test Cen­ter, Md.
Pho­to cred­it Army Pho­to
Click to enlarge

It’s all part of an effort to field a next-gen­er­a­tion tac­ti­cal vehi­cle that can hit speeds of 70mph, with­stand road­side bombs and oth­er threats, dri­ve through off-road ter­rain and fly through the air beneath a CH-47 Chi­nook or CH-53 heli­copter, ser­vice offi­cials said.

“The whole pur­pose of this TD (tech­nol­o­gy devel­op­ment) phase is to get the require­ments right,” said Brett John­son, JLTV chief engi­neer.

The three con­trac­tor teams for the cur­rent 27-month tech­nol­o­gy devel­op­ment phase — BAE-Nav­is­tar, Lock­heed-BAE and Gen­er­al Tac­ti­cal Vehi­cles — each deliv­ered sev­en pro­to­type vehi­cles engi­neered to reach an unprece­dent­ed blend of per­for­mance, pay­load and pro­tec­tion.

Fol­low­ing a Mile­stone C pro­duc­tion deci­sion in 2013, the Army plans to buy 55,000 JLTVs and the Marines plan to buy 5,500. Full pro­duc­tion is slat­ed for 2015.

“The JLTV Pro­gram is imple­ment­ing the com­pet­i­tive pro­to­typ­ing pol­i­cy for the Army. What we have in this tech­nol­o­gy devel­op­ment phase is three con­trac­tor teams to help us inform our require­ments,” said Lt. Col. Wolf­gang Peter­man, JLTV prod­uct man­ag­er. “As we get results from the test­ing, we will feed that back into our require­ments.”

The Army-led pro­gram will put the vehi­cles through blast, mobil­i­ty and per­for­mance test­ing at Aberdeen Prov­ing Ground, Md., and reli­a­bil­i­ty test­ing at Yuma Prov­ing Ground, Ariz., as part of an effort to refine the require­ments for the next phase of the com­pe­ti­tion, the Engi­neer­ing and Man­u­fac­tur­ing Devel­op­ment, or EMD phase.

Bal­lis­tic hulls and armor coupons have already been test­ed; now the vehi­cles will under­go addi­tion­al sur­viv­abil­i­ty test­ing against a vari­ety of known and antic­i­pat­ed threats, pro­gram offi­cials said.

A for­mal request for pro­pos­al for the EMD phase is slat­ed for June 2011, to be fol­lowed by con­tract awards in Decem­ber of 2011, Peter­man said.

“When we go to EMD phase, it will be a full and open com­pe­ti­tion again. Our plan is to award two con­tracts for the EMD phase,” he said.

The test­ing dur­ing the TD phase is aimed at low­er­ing risk and pro­duc­tion costs by find­ing and solv­ing chal­lenges which may arise ear­li­er in the devel­op­men­tal process.

“We’re devel­op­ing pro­to­types and require­ments for the next phase so that when we enter the next phase we will have a low-risk pro­gram,” said Dean John­son, Marine Corps deputy pro­gram man­ag­er, JLTV.

The vehi­cles are built with 85-per­cent com­mon parts. For exam­ple, all of the JLTV vari­ants are built with a 2500 series Alli­son 6‑speed auto­mat­ic trans­mis­sion.

There are three dif­fer­ent vari­ants or cat­e­gories of JLTV:

— Cat­e­go­ry A is a four-per­son gen­er­al pur­pose vehi­cle with a curb weight of 13,000 pounds and the abil­i­ty to car­ry 3,500 pounds of pay­load and 3,500 pounds of add-on armor.

— Cat­e­go­ry B is six-per­son infantry car­ri­er with a curb weight of 15,000 pounds. It is able to add 4,500 pounds of pay­load and 4,000 pounds of armor.

— Cat­e­go­ry C vehi­cle is a two pas­sen­ger util­i­ty vehi­cle with a short cab/open bed for haul­ing equip­ment or putting on shel­ters. Cat­e­go­ry C has a curb weight of 15,000 pounds can car­ry 5,100 pounds of pay­load with crew, fuel, gear and a full com­pli­ment of armor.

In addi­tion, the Army and Marine Corps are prepar­ing to accept deliv­ery of a new Enhanced Pro­tec­tion Vari­ant of the JLTV, which is a mod­i­fied Cat­e­go­ry A vehi­cle designed with addi­tion­al pro­tec­tions. Each of the ven­dors will deliv­er an Enhanced Pro­tec­tion Vari­ant in the next sev­er­al months, pro­gram offi­cials said.

Engi­neer­ing Chal­lenge

The JLTV is engi­neered to push the enve­lope of tech­no­log­i­cal pos­si­bil­i­ty and build a light tac­ti­cal, mobile vehi­cle which has the abil­i­ty to thwart IEDs and oth­er kinds of attacks.

“The basic chal­lenge that we faced was try­ing to cre­ate a total inte­grat­ed pro­to­type, not so much a par­tic­u­lar chal­lenge with a sub­sys­tem but rather putting all the sys­tems togeth­er and still meet­ing our full pay­load, full pro­tec­tion and full per­for­mance enve­lope,” said Brett John­son.

The vehi­cles are built with vari­able ride height sus­pen­sion designed to give the chas­sis the abil­i­ty to raise and low­er off the ground depend­ing on road con­di­tions. The sus­pen­sion can raise and low­er the vehi­cles from five inch­es off the ground to fit on some of the Marine Corps ships all the way up to up to 22 inch­es off the ground for max­i­mum pro­tec­tion from under blast attacks and IEDs, Brett John­son said.

“Two of the ven­dors chose an air-bag style sus­pen­sion to raise and low­er the vehi­cle which you see on com­mer­cial tucks. The third one chose a hydrop­nue­mat­ic strut with a com­press­ible flu­id to raise and low­er the vehi­cle,” he said.

Each one of the pro­to­type vehi­cles has four-wheel inde­pen­dent sus­pen­sion which uses a dou­ble-wish­bone race­car-like sus­pen­sion — two wish­bone-shaped struc­tures that work to keep the vehicle’s wheels in a per­pen­dic­u­lar posi­tion to the ground, Brett John­son said.

Also, all the ven­dors employed a cen­tral tire infla­tion sys­tem which is an on-the-fly sys­tem that can reg­u­late tire pres­sure; the sys­tem can adjust tire pres­sure from high­er pres­sures for high­er speed con­di­tions on flat­ter roads to much low­er pres­sures in soft soil such as sand or mud, said Brett John­son.

Instead of hav­ing a belt-dri­ven alter­na­tor, the vehi­cles are built with an inte­grat­ed gen­er­at­ing sys­tem that is sand­wiched between the engine and trans­mis­sion.

“A flat alter­na­tor is more effi­cient. These are very effi­cient machines for gen­er­at­ing pow­er, much more than a belt-dri­ven machine,” said Brett John­son.

The JLTV has a require­ment to gen­er­ate 30 kilo­watts of exportable pow­er — to include 10 kilo­watts of on-board 28-volt DC pow­er.

“There’s a point at which alter­na­tors reach their max­i­mum. We have as big as 500 amp alter­na­tors out there; the prob­lem is they take a lot of RPMs in the engine to keep the speed high enough on a belt-dri­ven sys­tem to get the pow­er out of them. Once you get past about 1500 RPMs — you are rac­ing the engine. These sys­tems can gen­er­ate steady stream of three to four times as much pow­er at 1300 RPMs,” said Brett John­son.

There is a require­ment for a gen­er­al range of 400 miles in this phase, but that will like­ly low­er to 325 after look­ing at how much fuel the vehi­cles can car­ry, he said.

Inter­na­tion­al Efforts

The U.S. and Aus­tralia have entered into a Land Force Capa­bil­i­ty Mod­ern­iza­tion Project Arrange­ment for the TD phase of the JLTV, effec­tive as of Jan­u­ary of last year.

The Aus­tralian vehi­cles will fea­ture right-hand oper­a­tion, but the vehi­cles will main­tain 90-per­cent com­mon­al­i­ty with the left-hand­ed pro­to­types. In addi­tion, the Aus­tralian vehi­cles will not exceed a 20 kg weight dif­fer­ence. Aus­tralia has con­tributed $30 mil­lion to the JLTV effort.

“We want trans­porta­bil­i­ty and reli­a­bil­i­ty as well. We decid­ed to invest in the U.S. pro­gram because their pro­gram meets a lot of our require­ments. We are fight­ing the same fight and fac­ing the same threats that the U.S. Army faces,” said Aus­tralian Army Lt. Col. Robin Peter­son, JLTV pro­gram man­ag­er.

The U.S.-Australian col­lab­o­ra­tion is aimed at reduc­ing risk, low­er­ing costs and enhanc­ing test­ing and sim­u­la­tion for both coun­tries.

Source:
U.S. Depart­ment of Defense
Office of the Assis­tant Sec­re­tary of Defense (Pub­lic Affairs)

Team GlobDef

Team GlobDef

Seit 2001 ist GlobalDefence.net im Internet unterwegs, um mit eigenen Analysen, interessanten Kooperationen und umfassenden Informationen für einen spannenden Überblick der Weltlage zu sorgen. GlobalDefenc.net war dabei die erste deutschsprachige Internetseite, die mit dem Schwerpunkt Sicherheitspolitik außerhalb von Hochschulen oder Instituten aufgetreten ist.

Alle Beiträge ansehen von Team GlobDef →