M1 Abrams gas turbine engine question.

nightsight971

New Member
Hello my fellow military techies,

I have been watching and hoping for the M1 Abrams or Leapord 2 to be sent to Ukraine.

They state the Leopard is easier logistically since it takes diesel gas, but I am confused.

It was my understanding for a long time that the plus side of the M1 Abrams jet turbine engine was that it could run on many types of fuel.

I had heard that if it burns, you can use it for fuel in the Abrams. It seems now that is not the case and it needs a special jet fuel.

Seems odd we would design it like that.
 

FormerDirtDart

Well-Known Member
Hello my fellow military techies,

I have been watching and hoping for the M1 Abrams or Leapord 2 to be sent to Ukraine.

They state the Leopard is easier logistically since it takes diesel gas, but I am confused.

It was my understanding for a long time that the plus side of the M1 Abrams jet turbine engine was that it could run on many types of fuel.

I had heard that if it burns, you can use it for fuel in the Abrams. It seems now that is not the case and it needs a special jet fuel.

Seems odd we would design it like that.
The M1 has a turbine engine. It is not a "jet engine". Turbines do not require jet fuel. All tactical vehicles in the US military run JP8. It's a logistics decision, not a mechanical requirement. Prior to 1990 all those vehicles ran on diesel. If M1s are donated to Ukraine they can easily be set up to run diesel
 

OPSSG

Super Moderator
Staff member
Part 1 of 3: Free The Leopards

They state the Leopard is easier logistically…
1. All Main Battle Tanks (MBTs), be it Leopard 2s, Challenger 2s or even M1A2s, in NATO service, need trained crews, maintenance and logistics support — it’s not as easy to maintain and support as many claim it to be. The more diverse the vehicle fleet, the bigger the challenge for Ukrainian Army logisticians.

2. As Lt. Gen. (Retired) Mark Hertling explains, below:

(a) More importantly, Leopard 2s and M1A2s use a 120mm main gun, which is a different ammo type to the 125mm ammo used in the T-90/T-72 series. The plus side of modern Leopard 2s and M1A2s compared to the T-90/T-72 series is better armour, more powerful engines and a better one piece 120mm sabot round that has no problem cutting through the T-90’s inferior armour. Germany’s DM63 APDSFS long rod penetrator anti-tank sabot ammunition will pass completely through any T-72. Whereas, the T-90 is just modernised T-72. It doesn't have any significant protection improvements, except ERA.​
(b) We need to ask 2 key questions:​
Q1: Can the Ukrainian Army quickly learn the capability of the Abrams (& Leopard II) the way it is designed to operate?​
Point to note: When the M1A2 or small critical parts in the MBT — break (which they do), & when those small & large replacement parts need replacing, & when it requires daily/ weekly/ monthly echelon maintenance. All these need to be done in the field, at war, under threat of Russian artillery fire.​
Q2: Will Ukraine have also trained those who do these things?​
Point to note: For the war in 2023, the Ukrainian Army will be training with tanks (to fight at tank company level), infantry, scouts, drones, artillery, engineers, intel. It is a lot more than just M1A2 or Leopard 2 crew training. The reason I ask these things is because armoured operations need to get all these things synchronized.​
3. These Western designed MBTs are also NOT as simple to maintain as a T-90/T-72 derivative (like the PT-91). And MBTs are often supported by specialist armoured recovery vehicles (ARVs) — it takes skill to operate the specialised lifting and recovery equipment to repair these MBTs. Further:
(a) the training for crew members and commanders of the Leopard 2s and M1A2s is pretty long and requires a certain minimum standard. A Leopard 2 crew training period takes about 6 weeks, for a basics only abbreviated short course.​
(b) in many countries operating the Leopard 2 or M1A2, the loader has 11 seconds to reload, when firing on the move — whereas the T-90/T-72 series has an auto loader — training for a Leopard 2 tank commander or a Leopard platoon commander needs another 9 weeks (after the basics short course), if they are to be tactically competent to fight at tank platoon level.​

4. I note:
(a) Germany’s Chancellor, Olaf Scholz, has not agreed to #FeeTheLeopards. Most Western engine power packs in armoured vehicles, including the EuroPowerPack (MTU MT883 Ka-500/501 diesel engine), will need ‘clean’ lubricants, hydraulic fluid, diesel fuel, to run — if not lots of problems with keeping these armoured vehicles running in the long haul.​
(b) that diesel engines have been destroyed by contaminated lubricants or hydraulic fluid. I have attended failure analysis class and seen these examples first hand.​
 
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koxinga

Well-Known Member
The M1 has a turbine engine. It is not a "jet engine". Turbines do not require jet fuel. All tactical vehicles in the US military run JP8. It's a logistics decision, not a mechanical requirement. Prior to 1990 all those vehicles ran on diesel. If M1s are donated to Ukraine they can easily be set up to run diesel
The AGT15000 is a multi-fuel engine and in addition to JP-8, it is able to run on diesel #1 and #2. That said, different types of fuel have different levels of viscosity and volatility (combustion). Engines and engine management systems are usually tune to a certain range of fuel to achieve optimal efficiency and reliability.

While the AGT15000 can run on diesel, the question is how that impacts the reliability and MTBF of the engines. We do have data points on this. The Australian Army appears to run their M1s on diesel (not sure #1 or #2) but MTBF has not been as high as the US Army/USMC. More importantly, it requires dedicated facilities to maintain.


I think the concerns about logistics and maintenance are valid. MTU is next door in Germany. Leopard tank engines (MTU Ka501s) can be overhauled there. If they bring the M1s over and running on diesels, in all likelihood, they will have to come with a ton of spares engines for field swaps, since there are no D level facilities in Europe until the Polish facility comes on line.


US/NATO has been looking at the single fuel concept (SFC) for a while. But in practice, that's another story.
 

Rob c

The Bunker Group
Verified Defense Pro
The M1 has a turbine engine. It is not a "jet engine". Turbines do not require jet fuel. All tactical vehicles in the US military run JP8. It's a logistics decision, not a mechanical requirement. Prior to 1990 all those vehicles ran on diesel. If M1s are donated to Ukraine they can easily be set up to run diesel
Turbine engines and jet engines work on the same principle and as long as the fuel control unit is set up correctly they will run on just about anything that will burn. now days with electronic fuel control units it is quite simple, but even older engines were adaptable. I remember reading spec's when I was in D Eng that the then navy Wasp helicopter could be set up to run on ships diesel. When went to US bases with the Skyhawk we had to change from F34 to JP8 which was just meant moving a leaver from one slot to another. The only difference was a slight drop in range due to the lighter S.G.
 

koxinga

Well-Known Member
they will run on just about anything that will burn
Yes, it will run, but the question is what that does to the engine on the long run, in a region where there are no maintenance facility.

Personally, I am skeptical of the multi-fuel promise. If electronic wizardry alone can solve the difference between different compression ratios of diesel and gasoline, we would all have an easier time at the pump.
 

StobieWan

Super Moderator
Staff member
Yes, it will run, but the question is what that does to the engine on the long run, in a region where there are no maintenance facility.

Personally, I am skeptical of the multi-fuel promise. If electronic wizardry alone can solve the difference between different compression ratios of diesel and gasoline, we would all have an easier time at the pump.
GT's run fine on quality fuel, without much regard to what that fuel is - there are other complications for aircraft, like anti-static additives and so forth, but for a tank or other ground vehicle running at sea level or near enough, running it on JP8 or diesel makes no difference.

GT's have basically been multifuel since their inception - the way they work makes them relatively agnostic about what they're running on - as long as the fuel selected is free of contaminants and so forth, it's not a big deal.
 

Rob c

The Bunker Group
Verified Defense Pro
Yes, it will run, but the question is what that does to the engine on the long run, in a region where there are no maintenance facility.

Personally, I am skeptical of the multi-fuel promise. If electronic wizardry alone can solve the difference between different compression ratios of diesel and gasoline, we would all have an easier time at the pump.
Just remember that the gas turbine runs on a continuous burn cycle not the Otto cycle of a piston engine ( it is similar to a continuous Otto cycle) and once running does not require the high compression of a diesel engine for compression ignition or spark plugs of a gasoline engine.. It requires the right air fuel ratio to extract the most energy available from the fuel it is using. The reason that Gas Turbines use a lot of fuel is to keep the temperatures in the engine under control (cooling) and up to 80% of the power of the engine is used to supply air to the engine for cooling and not combustion. this figure has been improving over the years as new materials have allowed the engines to run hotter. As long as the fuel is clean, what the fuel is will have little impact on either the performance or maintenance of the engine.
 

John Fedup

The Bunker Group
From an application POV, the diesel and GT both utilize similar fuels as per above so the main advantages for diesel are reduced consumption and fewer tanker vehicles required for fuel logistics. I think my earlier comment about more available diesel mechanics is also valid so this what makes the Leo2 a better option but as others have pointed out there aren’t many available for immediate use. Perhaps the US should match any Leo donations with M1s and a tanker vehicle.
 

Terran

Well-Known Member
From an application POV, the diesel and GT both utilize similar fuels as per above so the main advantages for diesel are reduced consumption and fewer tanker vehicles required for fuel logistics. I think my earlier comment about more available diesel mechanics is also valid so this what makes the Leo2 a better option but as others have pointed out there aren’t many available for immediate use. Perhaps the US should match any Leo donations with M1s and a tanker vehicle.
The degree is often overstated however to put it in simple terms The Abrams fuel Econ would be about .6 gallons to the mile. A Leo would be about 1 gallon to the mile. That’s obviously an over simplification but where 70 ton tanks are involved fuel is guzzled not sipped.
The bit where the Abrams suffers on fuel efficiency is in stationary watch. Where operating systems of the tank needs power but the tank isn’t charging. That requires either batteries, an APU or running the engine. Abrams was supposed to have an APU however in practice this hasn’t happened until the latest power pack modification.
There were attempts but the system an air conditioner sized box bolted on to the rear right corner of the tank had a habit of being knocked off crashed into and generally smashed. Batteries were used as an interim solution until they finally integrated the APU into the power pack.
Ukraine’s favorite tank; The T80 also uses a gas turbine in the T80U line. It’s an older design and is supposed to similarly have an external APU. There is also the Ukrainian T80UD which swapped the Turbine for a 2 stroke Diesel. Ukraine was left post Soviet break up with a hodgepodge fleet some T80U some T80UD
As well as T72 and T64. So Ukraine likely has more familiarity with gas turbines that most give them credit for but it’s still a dramatically different engine than the Soviet model.
 
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OPSSG

Super Moderator
Staff member
Part 2 of 3: Free The Leopards

5. IMO, M-1A2s, with their modern optics, and AGT1500 engine (with fuel efficiency increased by 10% due to the DECU), while sophisticated, will be a huge pain for Ukrainian logisticians. The M1A2’s AGT1500 gas turbine consumes 11 gallons (35kg) of fuel per hour at idle. This is said to be 2 to 2.5 times more compared to Leopard 2. Most Leopard 2s and M1A2s also come with an APU, to keep the fuel consumption down.

(a) Russian diesel engines for the same horsepower range, tend to be less fuel efficient but can often tolerate usage that would destroy many a Western diesel engine design. I have been to Vietnam and met with locals who destroyed a fleet of world leading Western made off-highway vehicles due to their mindset problem of switching over to from Russian made off-highway trucks.​
(b) They basically ran the work-system such that the hydraulic fluid temperature was abnormally high, leading to failures in the fleet while under warranty. We had to bring in a team do a process improvement mapping to prevent the locals from doing the illogical from a Western maintenance perspective and preventing the locals from destroying the entire vehicle fleet while under warranty.​
(c) Likewise, Russian/Ukrainian thinking behind maintainability of vehicles is quite different from the typical NATO/Western mindset. What works for a Russian vehicle fleet may not work for a Western vehicle fleet. Even if we just look just at Soviet era tanks (eg. T-64s, T-72s, PT-91s, T-80s and T-90s, which I will hence forth refer to as “Warsaw Pack era tanks”), the diversity of the Ukrainian Army’s fleet is just crazy — which makes it difficult to support.​

6. I support #FeeTheLeopards but I am also a realist on the support requirements — which is not easy to meet.
(a) The Foreign Ministers of the Baltic states issue joint statement calling on Germany to release the Leopard 2s. Currently, the US goal at Ukraine Contact Group is “working with Germany to unlock that decision” on Leopard 2 MBTs for Ukraine.​
(b) The G4/S4s of the Ukrainian Army have to nail the logistics and support or all of this talk of #FeeTheLeopards is going to be counter-productive, even outright harmful to Ukraine's cause, no matter how good it feels on a superficial level.​
(c) Ukraine has been given a hodgepodge of armoured vehicles (Warsaw Pack era tanks, IFVs, APCs, M113s, CV90s, AMX-10 RCs, MRAPS of all kinds & civilian vehicles) — this makes it much harder for the Ukrainian Army to stock parts & push support to the front.​
 
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koxinga

Well-Known Member
2022 was the phase of "getting whatever is available to Ukraine, especially stuff they already know how to operate".

Given this is the second year of the war, their stated ambition to recover the Crimea and at least to push the Russians back to the pre-war boundaries, it is probably better to get them started now on NATO spec hardware and learn on the job.

The Russian kit will still co-exist and tide over this period of transition and for a significant period of time. But their future lie firmly with the West. So to me, the logistic challenges that the UAF has to face is a bridge they have to cross, sooner or later. But they are not alone.
 

ngatimozart

Super Moderator
Staff member
Verified Defense Pro
2022 was the phase of "getting whatever is available to Ukraine, especially stuff they already know how to operate".

Given this is the second year of the war, their stated ambition to recover the Crimea and at least to push the Russians back to the pre-war boundaries, it is probably better to get them started now on NATO spec hardware and learn on the job.

The Russian kit will still co-exist and tide over this period of transition and for a significant period of time. But their future lie firmly with the West. So to me, the logistic challenges that the UAF has to face is a bridge they have to cross, sooner or later. But they are not alone.
It's not the second year of the war; the war started on 24/02/2022. Today is 25/01/2023 so we are still in the first year of the war. The second year starts 30 days from now and a lot can happen in those next 30 days.
 

John Fedup

The Bunker Group
Have posted this here as it seems like the best location. It is a rather dated experience of a M1 operator’s account of working with a Leo2. Nothing surprising and it seems like a reasonable assessment. Needless to say both tanks have received numerous important upgrades since 1991.

 

OPSSG

Super Moderator
Staff member
Part 3 of 3: Free The Leopards

7. The number of British Challenger 2s being sent is a token, and the same will be true for the French Leclerc, if it is given.

(a) Finally, after sustained pressure, Germany has freed the Leopard 2s — Chancellor Olaf Scholz has announced his approval to send Leopard 2s to Ukraine as part of an address in German parliament. The real dynamics will play-out between the M1A2 Abrams and Leopard 2 based on how many arrive and by when. Therefore, I think that supportability and maintenance will be a big issues for 2023 to 2024.​
(b) IMO, deliveries of new IFVs and 8x8s, like the Bradley and Stryker, are more significant than Leopard 2 tanks because Ukraine lacks enough IFVs/8x8s and the relative improvement of a Bradley or a Stryker 8x8 over BMP-1 or MRAP is even greater than Leopard 2 over many Ukrainian tanks.​

8. Hats off to the Ukrainian Army logisticians (G4/S4 branch) for trying to support such a diverse vehicle fleet. But even if Germany ultimately agrees, #FeeTheLeopards is not a magic bullet, or an alternative to combined arms warfare competence.
Not sure if the US will offer tanks with DU armour.
9. Very unlikely and suggested in your link— given the amount of tank losses taken by both sides to-date and more tank losses are expected in Ukraine for the fight in 2023. A Foreign Military Sales approved armour package will be installed in Ukrainian M1A2 turrets.

10. The version being sent is M1A2, which is great.
 
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Pukovnik7

New Member
Hello my fellow military techies,

I have been watching and hoping for the M1 Abrams or Leapord 2 to be sent to Ukraine.

They state the Leopard is easier logistically since it takes diesel gas, but I am confused.

It was my understanding for a long time that the plus side of the M1 Abrams jet turbine engine was that it could run on many types of fuel.

I had heard that if it burns, you can use it for fuel in the Abrams. It seems now that is not the case and it needs a special jet fuel.

Seems odd we would design it like that.
1) M1 Abrams doesn't have jet turbine, it has gas turbine. And yes, it can run on many types of fuel. However...
2) Modern diesel engines have multifuel capability, so that "runs on many types of fuel" bit is no longer an advantage.

Obviously, both engines run best on the fuel they are designed for (JP-8 for Abrams, diesel for Leopard), but they can use other types of fuel.
 

John Fedup

The Bunker Group
Wondering how forgiving wrt to $hit fuel GTs are compared to diesels? From my experience with marine diesels, 95% of all problems are related to water/contaminants in fuel.
 

FormerDirtDart

Well-Known Member
For all the continued talk of running M1s on diesel, according to reporting in 1989 when the US Army was transition their M1's from DF-2 to JP-8 the change resulted in reduced fuel economy. https://web.archive.org/web/2023012.../news/ct-xpm-1989-09-01-8901090654-story.html
That's right, the M1 ran better on DF-2.
Additionally, my understanding is that the Australian Army feeds their M1s a hearty diet of diesel

Push comes to shove, I'm willing to bet the Ukrainians will be able to run M1s on a mixture of sunflower seed oil and captured vodka. /sarc/
 
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