Thread by @delfoarse

Many people concern Ukrainian Army cannot maintain and sustain M1 Abrams.

AGT1500 Turboshaft Gas Turbine is widley believed to be a problem because it drains fuel a lot.

But it's not true.

Fuel efficiency of M1 Abrams tank got significantly improved compared to the past.

I. Fuel consumption during vehicle's movement

Figures indicating characteristics of various engines.

What you only need to see here is BSFC values.

Unit: lb/hp/hr

M1: 0.5
Leopard2/K1 88: 0.414
K2: 0.369
Challenger 2: 0.364
T-80BV: 0.525
T-80U/BVM: 0.503

In 2006,Total Integrated Engine Revitalization (TIGER) progam added Digital Engine Control Unit(DECU) to M1's AGT1500 engine.

It improves AGT1500's fuel efficiency by 10% percent.

ECU had existed for M1s in the past but it was analogue type.

DECU monitors and controls many aspects of engine performance.

It was type-classfied as EA-J7 by US DOD.

II. Idle fuel consumption issue

AGT1500 gas turbine consume 11 gallons of fuel(35kg) per hour at idle. This is said to be 2.5 times more compared to Leopard 2.

Fortunately EA-J7 DECU guarantees 20% lower idle fuel consumption for M1 tank but it's not enough.

Auxiliary Power Unit also gives reduction to fuel consumption at idle status.

There has been several types of APU adopted for M1 Abrams variants. Among them what we look at right now here is Under-Armor Auxiliary Power Unit(UAAPU) for M1A2 SEPv3

According to DOT&E FY20 report it's said "Fuel usage when operating the Abrams M1A2 SEPv3 with the UAAPU was 78 percent less than the amount used when running the main engine at idle for the same amount of time."

III. Jet fuel for turbine engine

AGT1500 is a multifuel engine able to consume many different types o' fuel.

During the cold war US M1 had used DF-2 diesel fuel without problem.

Then JP-8 got considered and adopted for a standardization purpose in logistics system.

IV. Maintenance

AGT1500 is modular in its design and without cylinder it has fewer parts than common diesel engines.

Leading to easy repair and maintenance.

Engine overhaul programs like PROSE and TIGER made its core parts more durable.

In short, DECU provides 10% less fuel comsumption on the move and 20% less at idle.

APU gurantees 78% better fuel efficiency at idle status in maximum.

a combination of DECU and APU can give AGT1500 82+% less idle fuel consumption(2gallons per an hour).

pretty maintainabe.

US Official once said there would be difficulties for Ukraine to use and maintain M1 Abrams.

At that time I assumed it was an expression of hesitation as I already know features explained above.

Now about 30 Abrams are on standby headed to Ukraine. Let's wish em' a good luck.