Based on the figures provided in these tables, it looks like the CATTB would provide armour protection far short of its own massive size?
My friend's calculations suggest that at best the front of the turret of this tank would only provide protection equivalent to about 530mm RHA. According to him the main reason for this is the abnormally low density of the armour which is 40-50 inches thick.
Is this because the CATTB's armour was just plain counterweight blocks and did not feature DU composite armour similar to that found on the M1A1HC and M1A2. Or is there something else going on?
Looking forward to professional answers
Based on the figures provided in these tables, it looks like the CATTB would provide armour protection far short of its own massive size?
My friend's calculations suggest that at best the front of the turret of this tank would only provide protection equivalent to about 530mm RHA. According to him the main reason for this is the abnormally low density of the armour which is 40-50 inches thick.
I'd go so far as to suggest that the last two letters of the acronym explain this: Test Bed. CATTB was a technology demonstrator for future tanks. There was likely no requirement to be particularly well armoured, and presumably no armour that needed to be demonstrated on an AFV. So why go to the cost and effort of providing especially heavy armour?
Based on the figures provided in these tables, it looks like the CATTB would provide armour protection far short of its own massive size?
My friend's calculations suggest that at best the front of the turret of this tank would only provide protection equivalent to about 530mm RHA. According to him the main reason for this is the abnormally low density of the armour which is 40-50 inches thick.
Your friend calculations are wrong, because the 50" special armor of the CATTB turret front has an area density of 750 lbs / ft² (3362 kg / m²), which is already way more than the 199 lbs / ft² (972 kg / m²) area density of the 1976 Chobham armour.
Based on the figures provided in these tables, it looks like the CATTB would provide armour protection far short of its own massive size?
My friend's calculations suggest that at best the front of the turret of this tank would only provide protection equivalent to about 530mm RHA. According to him the main reason for this is the abnormally low density of the armour which is 40-50 inches thick.
Your friend calculations are wrong, because the 50" special armor of the CATTB turret front has an area density of 750 lbs / ft² (3362 kg / m²), which is already way more than the 199 lbs / ft² (972 kg / m²) area density of the 1976 Chobham armour.
WOW！wow, thank you very much for the valuable answers(๑><๑）.
and here is another question:
In the 1990s the CATTB faded into obscurity and another similar looking M1 variant with the same ATAC system, the "THUMPER", appeared.
Is it reasonable to assume that the THUMPER was a simplified version of the CATTB project, similar to the transformation of the MBT70 into the XM803 main battle tank?
Or are these two completely different projects.
In the 1990s the CATTB faded into obscurity and another similar looking M1 variant with the same ATAC system, the "THUMPER", appeared.
Is it reasonable to assume that the THUMPER was a simplified version of the CATTB project, similar to the transformation of the MBT70 into the XM803 main battle tank?
Or are these two completely different proj
The THUMPER's "real" name is ATAC Sytem Demonstrator, it got built in 1988 only to test the ATAC system (ATACS), XM291 gun + XM291 auto loader and few other things of the ATAC System, like a rearm port in the turret rear and a stub case ejector right behind the XM291 breach.
To make the whole system work, they had to build a new turret and that's what the THUMPER is, just the ATACS demonstrator, although they used it later to test various system modifications to reduce the flexibility of gun tube and of the whole system, in the end the THUMPER tested the XM291 120mm tube in three different lengths.
The THUMPER has nothing to do with the CATTB apart from the ATAC System.
Edit: The CATTB got built in 1993 and used a normal M1A1 chassis, it only received it's "real" chassis in 1994, that's why theres photos of the CATTB with 2 different chassis configurations.
The CATTB's turret got finished first, then they had to use a normal M1A1 hull to test it while they had to wait for it's real chassis to be ready.
This is from the Swiss Government study using their own 140mm gun and ammo. The XM964 APFSDS-T used by the XM291 140mm gun is longer and heavier.
The length of the XM291 140mm tube is identical to the XM291 120mm L/55 tube.
This is the XM291 using the 120mm tube, most of the other photos of the XM291 shows the 140mm tube.
Thank you all for your answers to my questions about CATTB's firepower and defensive capabilities.
The next question I would like to ask is: why did the CATTB have a large number of external grenade launchers. Is this just for perception jamming like the current main battle tanks.
Or are these launchers also capable of killing close range infantry with high explosive grenades in special circumstances.
Another theory is that this is to make room for new APS systems like the Trophy and Iron Fist to be added in the mid-term upgrades.
Also, from what I've found on Google, the Army wanted to launch a diesel engine called the XAP-1450 in the 1990s, which appeared to be a Cummins or Lycoming product, with a new generation of transmissions to achieve lower fuel consumption and noise.
But the XAP-1450 did not make it into production. What were the technical features of this engine, and were there other reasons for its eventual demise than a reduction in funding?
PS: In a "magical" game called "Armour Wars", CATTB also had the option of a "BAE 1750 horsepower hybrid engine "Is this pure fabrication or is there a similar historical prototype?
Also, did Honeywell have any historical ideas or plans to increase the power output of the AGT1500 engine?
Also, from what I've found on Google, the Army wanted to launch a diesel engine called the XAP-1450 in the 1990s, which appeared to be a Cummins or Lycoming product, with a new generation of transmissions to achieve lower fuel consumption and noise.
But the XAP-1450 did not make it into production. What were the technical features of this engine, and were there other reasons for its eventual demise than a reduction in funding?
PS: In a "magical" game called "Armour Wars", CATTB also had the option of a "BAE 1750 horsepower hybrid engine "Is this pure fabrication or is there a similar historical prototype?
Also, did Honeywell have any historical ideas or plans to increase the power output of the AGT1500 engine?
Copiously Long Post to talk about copious amounts of grenade launchers
Thank you all for your answers to my questions about CATTB's firepower and defensive capabilities.
The next question I would like to ask is: why did the CATTB have a large number of external grenade launchers. Is this just for perception jamming like the current main battle tanks.
TL: DR Pretty much, but there is more nuance and speculation.
The copious amount of smoke grenade launchers is related to VIDS, or Vehicle Integrated Defense System and the design of a grenade launcher. This system was meant to be fitted on the Block III tank. One of the many components utilized for VIDS was the MSGL, Multi-Salvo ( Smoke ) Grenade Launcher or Rapid Obscuration System. MSGL/ROS was designed to rapidly obscure the tank if a threat was detected through one of the many types of sensors by IR and Visual smoke grenades, basically an American predecessor to Rheinmetall ROSY.
One of the purposes of MSGL/ROS seen on the CATTB was to replace the M257 Smoke Launchers and all other smoke launchers in service (M243, M250, etc). The MSGL was an attempt to standardize the various smoke grenade launchers found on a variety of different U.S Vehicles. MSGL was also made to address the perceived deficiency that the current U.S smoke screen systems don't allow for operator selective obfuscation of the top, rear, or sides of the vehicle . This is probably why there are smoke grenades mounted on the sides of CATTB's turret that are also pointing up, and to the rear.
MSGL is similar to the M257, with the main visual difference being that all four tubes are mounted parallel to each other producing two vertical 'sets’ mounted 15 degrees apart, producing a coverage of only 30 degrees. This meant unlike M257, where each tube is spaced 15 degreesapart allowing for 60 degrees of coverage for one launcher, you would require four instead of two separate launchers to make a 120 degree smokescreen coverage. This is probably the one of the main reasons for the amount of smoke launchers at the front of CATTB, to achieve optimal smoke coverage of 120 degrees. As it states in MSGL abbreviated Analysis:
Beyond that, MSGL had the advantages of requiring far less mounting surface (85 sq IN vs 58 sq IN), allowing for better placement of smoke launchers across the vehicle, being slightly lighter and allowing easier replacement of the four discharger tubes. As the mounting bolts of the tubes are accessible at the front, whereas on the M257, they’re only accessible at the rear of the mounting bracket. It was also rated as being better for overhead smoke than M257, receiving an ‘excellent’ while M257 got ‘good’, however that rating is quite dubious.
The ultimate conclusion of this Analysis was that MSGL provides a marginal improvement over m257, while costing 9-12 million more to develop, produce, field and sustain. However m257 might not be fit for future HFM (Heavy Force modernization, or Armored systems modernization) vehicles, due to being defined much earlier than HFM technical characteristics.
Back to MSGL/ROS, The U.S army also wanted the MSGL/ROS to be capable of firing multiple salvos ( Smoke grenades covering 120 Degrees ) whenever a threat was detected, and depending on the type of threat and what grenades where available, those dictated the response. These factors would, combined with the others, increase the amount of smoke needed IMO.
I think that all the launchers mounted on the CATTB turret would be armed with both IR and VIS smoke with both mounted in the two 'set's, so that if a Laser designator or Laser Beamrider ATGM threat was detected, the VIDS could decide what type of grenade it uses. This would easily allow for multiple salvos of both types. Visual Below:
Now for VIDS. It was an American Active Protection System utilizing sensors, inter/ intra-vehicular data exchange networks, warning receivers, DEW’s, obscurants like IR or Visual smoke (fired from MSGL) or chaff, spoofing behaviour like flares, and a jamming system for soft kill effect against missiles, like Shtora or AN/VLQ 6 or 8. VIDS was tested through SIMNET, with a Full Crew Simulator ( with 3 crewmen instead of 4 ) of a M1 Abrams equipped with VIDS.
VIDS, as described by [SECOND DRAFT REGARDING] VEHICLE INTEGRATED DEFENSE SYSTEM FUNCTIONAL DESCRIPTION which is 76 pages long states:
The proposed VIDS system is composed of four distinct elements:
- The track vehicle - assumed to be essentially an M1A1 tank, with respect to hull
and turret dynamics, weapons and ammunition characteristics. Allowances are
assumed for a reconfigured crew compartment (possibly 3 man only) and an
additional, vertical launch weapon
- The Sensor Suite and Integrating System - a multi-faceted system capable of
collecting and assessing information presented over a broad energy spectrum.
- The Control and Display system - assumed to be compatible with the Control and
Display system available in the M1A2 tank.
- The Countermeasure system - both automated and manual, consisting of direct
fire weapons, transmission jamming systems, obscurants, spoofing behaviors,
and internal and external data exchange networks
CATTB was equipped with a VIDS, or a version of it and was meant to test it out in Q2 1991. CATTB VIDS utilised famously the MSGL/ROS launchers, possibly with both smoke nades for IR and Visual. Though the rest, IDK. It probably should have almost all the optical and warning receiver sensors, the display panels like CCDP (commanders control and display panel for VIDS), jammers (MCD or Missile countermeasure device) for MMW and RF ATGMS, and automatic turret slew to detected highest priority target (counterfire). The more exotic stuff (Multi-sensor target acquisition system/Commanders milli-meter wave radar, Optic Sensor, DEW, etc) I don't think were mounted on CATTB.
VIDS had three modes: Automatic, Semi-Automatic, and manual. Automatic made it so that the system would work entirely by it's own without input from the TC, whereas semi automatic required the TC to grip a palm switch on his Commanders Control Handle. Manual however, only made suggestions to the crew and warned them.
Also when counterfire would happen in automatic and semi, the gunner and commander wouldn't be able to manually cancel it through their controls, they would have to wait until it was done. IIRC
If you want, please go read the 76 page functional description report, operators manual and launcher Analysis, they are pretty damn interesting.
[SECOND DRAFT REGARDING] VEHICLE INTEGRATED DEFENSE SYSTEM FUNCTIONAL DESCRIPTION, it's 76 pages long but contains good info and pictures relating to both VIDS and SIMNET as a whole.
ADST Operators/Users Manual for the BDS-D VIDS-equipped M1, which has lots of info as well. 20 Pages long. Includes drawing of the CCDP, or Commanders Control and Display Panel, a legend of the various threat icons, among a whole lotta writing and other cool stuff.
ADST Software Maintenance Manual for the BDS-D VIDS-equipped M1(FINAL) has some stats on VIDS on it's last page.
I'll post Screenshots, but please still read the full documents. There will be info not screenshotted thats still highly relevant to VIDS and I can't describe these systems better.
Copiously Long Post to talk about copious amounts of grenade launchers
Thank you all for your answers to my questions about CATTB's firepower and defensive capabilities.
The next question I would like to ask is: why did the CATTB have a large number of external grenade launchers. Is this just for perception jamming like the current main battle tanks.
TL: DR Pretty much, but there is more nuance and speculation.
The copious amount of smoke grenade launchers is related to VIDS, or Vehicle Integrated Defense System and the design of a grenade launcher. This system was meant to be fitted on the Block III tank. One of the many components utilized for VIDS was the MSGL, Multi-Salvo ( Smoke ) Grenade Launcher or Rapid Obscuration System. MSGL/ROS was designed to rapidly obscure the tank if a threat was detected through one of the many types of sensors by IR and Visual smoke grenades, basically an American predecessor to Rheinmetall ROSY.
One of the purposes of MSGL/ROS seen on the CATTB was to replace the M257 Smoke Launchers and all other smoke launchers in service (M243, M250, etc). The MSGL was an attempt to standardize the various smoke grenade launchers found on a variety of different U.S Vehicles. MSGL was also made to address the perceived deficiency that the current U.S smoke screen systems don't allow for operator selective obfuscation of the top, rear, or sides of the vehicle . This is probably why there are smoke grenades mounted on the sides of CATTB's turret that are also pointing up, and to the rear.
MSGL is similar to the M257, with the main visual difference being that all four tubes are mounted parallel to each other producing two vertical 'sets’ mounted 15 degrees apart, producing a coverage of only 30 degrees. This meant unlike M257, where each tube is spaced 15 degreesapart allowing for 60 degrees of coverage for one launcher, you would require four instead of two separate launchers to make a 120 degree smokescreen coverage. This is probably the one of the main reasons for the amount of smoke launchers at the front of CATTB, to achieve optimal smoke coverage of 120 degrees. As it states in MSGL abbreviated Analysis:
Beyond that, MSGL had the advantages of requiring far less mounting surface (85 sq IN vs 58 sq IN), allowing for better placement of smoke launchers across the vehicle, being slightly lighter and allowing easier replacement of the four discharger tubes. As the mounting bolts of the tubes are accessible at the front, whereas on the M257, they’re only accessible at the rear of the mounting bracket. It was also rated as being better for overhead smoke than M257, receiving an ‘excellent’ while M257 got ‘good’, however that rating is quite dubious.
The ultimate conclusion of this Analysis was that MSGL provides a marginal improvement over m257, while costing 9-12 million more to develop, produce, field and sustain. However m257 might not be fit for future HFM (Heavy Force modernization, or Armored systems modernization) vehicles, due to being defined much earlier than HFM technical characteristics.
Back to MSGL/ROS, The U.S army also wanted the MSGL/ROS to be capable of firing multiple salvos ( Smoke grenades covering 120 Degrees ) whenever a threat was detected, and depending on the type of threat and what grenades where available, those dictated the response. These factors would, combined with the others, increase the amount of smoke needed IMO.
I think that all the launchers mounted on the CATTB turret would be armed with both IR and VIS smoke with both mounted in the two 'set's, so that if a Laser designator or Laser Beamrider ATGM threat was detected, the VIDS could decide what type of grenade it uses. This would easily allow for multiple salvos of both types. Visual Below:
Now for VIDS. It was an American Active Protection System utilizing sensors, inter/ intra-vehicular data exchange networks, warning receivers, DEW’s, obscurants like IR or Visual smoke (fired from MSGL) or chaff, spoofing behaviour like flares, and a jamming system for soft kill effect against missiles, like Shtora or AN/VLQ 6 or 8. VIDS was tested through SIMNET, with a Full Crew Simulator ( with 3 crewmen instead of 4 ) of a M1 Abrams equipped with VIDS.
VIDS, as described by [SECOND DRAFT REGARDING] VEHICLE INTEGRATED DEFENSE SYSTEM FUNCTIONAL DESCRIPTION which is 76 pages long states:
The proposed VIDS system is composed of four distinct elements:
- The track vehicle - assumed to be essentially an M1A1 tank, with respect to hull
and turret dynamics, weapons and ammunition characteristics. Allowances are
assumed for a reconfigured crew compartment (possibly 3 man only) and an
additional, vertical launch weapon
- The Sensor Suite and Integrating System - a multi-faceted system capable of
collecting and assessing information presented over a broad energy spectrum.
- The Control and Display system - assumed to be compatible with the Control and
Display system available in the M1A2 tank.
- The Countermeasure system - both automated and manual, consisting of direct
fire weapons, transmission jamming systems, obscurants, spoofing behaviors,
and internal and external data exchange networks
CATTB was equipped with a VIDS, or a version of it and was meant to test it out in Q2 1991. CATTB VIDS utilised famously the MSGL/ROS launchers, possibly with both smoke nades for IR and Visual. Though the rest, IDK. It probably should have almost all the optical and warning receiver sensors, the display panels like CCDP (commanders control and display panel for VIDS), jammers (MCD or Missile countermeasure device) for MMW and RF ATGMS, and automatic turret slew to detected highest priority target (counterfire). The more exotic stuff (Multi-sensor target acquisition system/Commanders milli-meter wave radar, Optic Sensor, DEW, etc) I don't think were mounted on CATTB.
VIDS had three modes: Automatic, Semi-Automatic, and manual. Automatic made it so that the system would work entirely by it's own without input from the TC, whereas semi automatic required the TC to grip a palm switch on his Commanders Control Handle. Manual however, only made suggestions to the crew and warned them.
Also when counterfire would happen in automatic and semi, the gunner and commander wouldn't be able to manually cancel it through their controls, they would have to wait until it was done. IIRC
[SECOND DRAFT REGARDING] VEHICLE INTEGRATED DEFENSE SYSTEM FUNCTIONAL DESCRIPTION, it's 76 pages long but contains good info and pictures relating to both VIDS and SIMNET as a whole.
ADST Operators/Users Manual for the BDS-D VIDS-equipped M1, which has lots of info as well. 20 Pages long. Includes drawing of the CCDP, or Commanders Control and Display Panel, a legend of the various threat icons, among a whole lotta writing and other cool stuff.
Multi-Salvo Grenade Launcher Abbreviated Analysis, full 42 page report, very cool as well.
I'll post Screenshots, but please still read the full documents. There will be info not screenshotted thats still highly relevant to VIDS and I can't describe these systems better.
[SECOND DRAFT REGARDING] VEHICLE INTEGRATED DEFENSE SYSTEM FUNCTIONAL DESCRIPTION, it's 76 pages long but contains good info and pictures relating to both VIDS and SIMNET as a whole.
Just in case people want the full document's for that image above, it's full of other interesting tidbits and images on other programs and initiatives:
These Files are located on USAHEC inside WILLIAM G.T. TUTTLE, JR. PAPERS; BOX 18, REPOSITORY REVIEW, ORGANIZATIONAL DOCUMENTS, 1990 inside various folders.
WILLIAM G.T. TUTTLE, JR. PAPERS; BOX 18, FOLDER 10, AMC TECHNOLOGY EXPO DOCUMENTS [PART 1 OF 3], 1990
https://emu.usahec.org/alma/multimedia/953686/20184655MN0014175.pdf PT 2
Other Cool Stuff like Combat Vehicle Suspension Technology ( Page 2 ), showing a great image of torsion vs hydro-pneumatic suspension systems and lists various reasons for why Hydro is better, a picture of the ADKEM missile with a little info and more.
More Relevant, I asked a guy ( CimaGarahau ) on reddit a few months back after I saw a post on the cattb with a very interesting image, 2 days later on Sturgeonshouse he posted the full document . Credits to him fully, It is an Incredible document and I am extremely grateful that he found it and decided to post it after I asked him. I will repost here. Hopefully he will be fine with it.
Thank you all for your answers to my questions about CATTB's firepower and defensive capabilities.
The next question I would like to ask is: why did the CATTB have a large number of external grenade launchers. Is this just for perception jamming like the current main battle tanks.
Or are these launchers also capable of killing close range infantry with high explosive grenades in special circumstances.
I'd wager there was some consideration of different munitions besides for conventional and infrared blocking (multi-spectral) smoke. I've read of aerosols that can stop/deflect a laser which could throw off a laser-guided ATGM for example.
The French GALIX system is supposed to have the option of less-than-lethal grenades for crowd control purposes and I wouldn't be surprised if they've considered a more lethal variety for close-in defense.
If it was supposed to be a unified complex for all vehicles, it would be able to fire masking and less-lethal grenades. Flashbangs and sting ball grenades are standard features on HMMWVs deploying for anti-riot pacification in U.S. cities with the National Guard along with the M5 MCCM.
If it was supposed to be a unified complex for all vehicles, it would be able to fire masking and less-lethal grenades. Flashbangs and sting ball grenades are standard features on HMMWVs deploying for anti-riot pacification in U.S. cities with the National Guard along with the M5 MCCM.
All modern ones are electrical. They use the vehicle's alternator to supply power. The main families are the M1/M2's M257 and M250, the Stryker/M104's M6, and the HMMWV's M305/M310. The M88's use whatever the M1 uses which is probably the M257 if it's not the M239s still.
If the CATTB was supposed to be a unified complex, and since the individual modules resemble the M305/M310 this is probably the case, they would all be electrical, 66mm, and employing everything from obscurants like the M90 multi-spectral grenade (or L8 RP) to the various riot control grenades.
All modern ones are electrical. They use the vehicle's alternator to supply power. The main families are the M1/M2's M257 and M250, the Stryker/M104's M6, and the HMMWV's M305/M310. The M88's use whatever the M1 uses which is probably the M257 if it's not the M239s still.
If the CATTB was supposed to be a unified complex, and since the individual modules resemble the M305/M310 this is probably the case, they would all be electrical, 66mm, and employing everything from obscurants like the M90 multi-spectral grenade (or L8 RP) to the various riot control grenades.
Does anyone have access to this report AD-B135 236, or this one TACOM-TR-13431-VOL-2?
It has additional information about the CATTB. I think USAHEC had the first one, but I'm not sure.
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