Evaluation of Aardvark Mk IV Flail - gichd

Evaluation of Aardvark Mk IV Flail 

DERA/LWS/LSAA/TRD000603/1.2 

Copy 1 of 10 

Cover + xii + 77 pages 

February 2001 

Mr. C A Leach 

DERA is an Agency of the UK Ministry of Defence

2 

Customer Information 

Customer Reference Number TBA 

Project Title Evaluation of Aardvark Mk IV 

Company Name Department For International 

Development 

Customer Contact Ms. A Docherty 

Contract Number TBA 

Milestone Number N/A 

Date Due (dd/mm/yyyy) 06/11/2000 

This Document was produced by DERA for Department For International 

Development Under Order/Contract reference TBA 

© Crown copyright 2001Defence Evaluation and Research Agency UK 

DERA/LWS/LSAA/TRD000603/1.2

Authorisation 

Prepared by Mr C A Leach 

Title Project Engineer 

Signature 

Date 26/02/2001 

Location DERA Chertsey 

Authorised by Mr J. Hambly 

Title Technical Manager 

Signature 

Date 

Principal authors 

Name Mr C A Leach 

Appointment Project Engineer 

Location DERA Chertsey 

DERA/LWS/LSAA/TRD000603/1.2 iii

Record of changes 

iv 

Issue Date Detail of Changes 

A 5/9/2000 Draft 

1.0 28/10/2000 Initial Issue 

1.1 6/11/2000 Minor Amendments 

1.2 26/02/2001 Additional Ammendments 


Abstract 

Aardvark Clearmine Ltd have upgraded their Aardvark flail unit, a system that 

has an already proven track record for detonating mines and clearing mine 

affected land. 

DERA undertook testing and evaluation of the system on behalf of DFID (the 

Department for International Development). The machine offered for trialing was 

the MK IV Aardvark Flail, which performed well throughout the trial completing all 

the tests adequately. 

Overall, the objectives of the trial, testing the improved power and performance, 

were achieved by demonstrating the concept of using a flail to clear mines and 

dense foliage from various terrain. As with most mechanical clearance processes 

the application of this equipment has to be in the context of the mine threat, type 

of terrain, climatic and environmental conditions and of the overall demining 

operation. 

DERA/LWS/LSAA/TRD000603/1.2 v

Executive Summary 

vi 

Aardvark Mine Clear Ltd have been designing and producing mechanical mine 

clearance equipment for the last 17 years, supplying 25 different countries. The 

latest version of the Aardvark Flail, the Mark IV, came to the trial with an 

extensive depth of knowledge and experience behind its design. 

The testing and evaluation of the upgraded Mk IV Aardvark was carried out by 

DERA on behalf of DFID (The Department For International Development). The 

tests were carried out at DERA’s Bagshot test track in the U.K. and were 

designed to test the potential of the new version of the Aardvark flail to clear antitank 

mines from roads, tracks and cross-country. Testing was done under the 

headings of Transportability, Mobility and Performance. No Survivability tests 

(Live Ordnance Encounter) were carried out since the Royal Netherlands Army 

Ammunition Branch had already carried out survival tests¹ on the Mk IV 

Aardvark. 

During the trial the Aardvark Mk IV proved to be a well thought out and 

engineered machine. It proved to be very manoeuvrable for a vehicle of its size. 

It has the ability to be stripped down to make it air-portable and it fits onto the 

back of a large low-loader truck making it easily transportable. 

Aardvark Mk IV showed a great ability as both a brush and vegetation clearer 

and a mine clearance device with the capability to reduce medium to heavy 

density foliage to fine mulch. In the limited tests carried out, the Mk IV cleared all 

the surrogate model mines in its path. 

This piece of equipment would be a valuable asset when used in the right 

environment and under appropriate circumstances. One characteristic of flails 

such as Aardvark is the amount of dust and debris that is thrown out during the 

clearance operation, this debris could contain disrupted mine parts and 

deactivated mines. 


List of contents 

Authorisation iii 

Record of changes iv 

Abstract v 

Executive Summary vi 

List of contents vii 

List of Tables ix 

List of Figures x 

1 Introduction 1 

1.1 Contractual Matters 1 

1.2 Background 1 

1.3 Mine Threat 1 

2 Aim 2 

3 Scope 2 

4 Improvements 4 

4.1 Additional Alterations: 5 

5 Trials Methodology 6 

5.1 General 6 

5.2 Sites 6 

5.3 Procedures 6 

6 Test Procedures and Results 7 

6.1 General 7 

6.2 Results 7 

6.3 Transportability 8 

6.4 Handling & Mobility 14 

6.5 Performance 34 

7 Conclusions 70 

8 Recommendations 71 

DERA/LWS/LSAA/TRD000603/1.2 vii

9 References 72 

A MK III AND MK IV RELATED PERFORMANCES 73 

B Summary of the Maintenance Schedule 74 

Distribution list 77 

Report documentation page 79 

viii 


List of Tables 

Table 4-1; Improvements 4 

Table 6-1; Summary of Tests 7 

Table 6-2; Principle Dimensions 8 

Table 6-3; Weight 10 

Table 6-4; Maximum Approach Angles 12 

Table 6-5; Turning Circle in forward and Reverse 14 

Table 6-6; Maximum gradient climbed 16 

Table 6-7; Table of Flailing Depth against Speed 18 

Table 6-8; Minefield Data Run 1 34 









DERA/LWS/LSAA/TRD000603/1.2 ix

List of Figures 

Figure 3-1; Aardvark Mark IV 3 

Figure 6-1; Plan view of Aardvark 8 

Figure 6-2; Measuring the height of Aardvark 9 

Figure 6-3; Using load cells to weigh Aardvark 11 

Figure 6-4; Measuring the Approach Angle with a straight edge and clinometer 13 

Figure 6-5; Aardvark on the gravel used for a Turning Circle 14 

Figure 6-6; Turning Circle 15 

Figure 6-7; Aardvark climbing Birch Up Road (Grad. 1 in 3.5) 17 

Figure 6-8; Graph of Flailing Depth against Speed 18 

Figure 6-9; Speed = 67m/hr, Depth = 528mm 19 

Figure 6-10; After flailing at 100m/hr 19 







Figure 6-17; Measuring Level used 23 

Figure 6-18; Aardvark entering the water filled gully 25 

Figure 6-19; At the end of the water run 25 

Figure 6-20; Foliage and terrain encountered in test area 27 

Figure 6-21; Aardvark at the start of the run 27 

Figure 6-22; Aardvark at the end of the run. Note the large debris thrown from the flail 28 

Figure 6-23; Test run after clearance, compare with Figure 6-14 28 

Figure 6-24; Test run before clearance 31 

Figure 6-25; Test run after clearance, 31 

Figure 6-26; View of Aardvark flailing the fire-break. 32 

Figure 6-27; Plan of Run 1 34 

Figure 6-28; Layout before Run 1 35 

Figure 6-29; Test area after Run 1 35 

Figure 6-30; Although just outside flail width (shown by pin above the mine) one fuse was 

removed. 36 

Figure 6-31; Giat mine with evidence of the flail encounter 36 

Figure 6-32; Position of mines after Run 1 37 


Figure 6-34; Layout of Run 2 39 

Figure 6-35; Test area after Run 2 39 

Figure 6-36; GIAT mine 25m behind Aardvark 40 

Figure 6-37; Spoil after run 2 40 


Figure 6-39; Layout of 3 43 

Figure 6-40; Aardvark flailing Run 3 43 

Figure 6-41; End of Run 3 44 

Figure 6-42; Spoil after Run 3 44 



x 


Figure 6-45; Aardvark just passed Run 4, GIAT in foreground 47 



Figure 6-48; End of Run 5 49 

Figure 6-49; Aardvark using the blast plate to fill in the scar left from the run 50 

Figure 6-50; Spoil left after Run 5 50 




Figure 6-54; GIAT in spoil after several hits 54 

Figure 6-55; Buried TMA-3 that partly fell outside of the flail width 54 



Figure 6-58; Dust profile when flailing 57 

Figure 6-59; GIAT in the foreground, broken mine casings in the background 58 

Figure 6-60; TMRP-6 and TMA-2 59 

Figure 6-61; TMA-3 outside flail width 59 



Figure 6-64; Aardvark having cleared Run 8 62 


Figure 6-66; TMA-3 outside flail width 63 



Figure 6-69; Aardvark flailing in ~200mm of water 66 

Figure 6-70; Run 9 after flailing 67 

Figure 6-71; State of the mines after flailing 67 

Figure 6-72; Summary of Mines Laid/Cleared 68 

DERA/LWS/LSAA/TRD000603/1.2 xi

xii 

This page is intentionally blank 


1 Introduction 

1.1 Contractual Matters 

1.1.1 This report has been issued by the Defence Evaluation Research Agency (DERA) for the 

Conflict and Humanitarian Affairs Department (CHAD) of The Department for 

International Development (DFID). 

1.1.2 Authority by DFID to undertake the trial was given by DFID fax dated 16 June 2000. 

1.1.3 A Trial Plan No. DERA/LSAA1/CMW8/13/03/01/01 was submitted to DFID on 13 March 

2000. 

1.1.4 This Trial Report constitutes part 1 of the overall trial and study package. 

1.2 Background 

1.2.1 Aardvark Mine Clear Ltd have developed a mark four version of their Aardvark flail with a 

larger power train and other improvements outlined in section 4. 

1.2.2 Equipment. The equipment evaluated by this trial was the Aardvark Mk IV Flail. 

(See Fig 3.1) 

1.2.3 Trial. The trial was conducted at DERA Bagshot test track between 26 – 30 July 2000. 

1.3 Mine Threat 

1.3.1 Generic wax filled model AT mines and solid metal model scatterable AT mines were 

used. 

1.3.2 Limitations of the Trial. The mines were not instrumented in any way. Therefore, 

although they were representative in size and weight of the generic mine threat, they 

gave no indication of actuation caused by pressure. The criteria used to determine 

whether detonation occurred are explained below. 

1.3.3 Mines End State. The mines were inspected after each test to determine the damage. 

Mines that were struck on the fuse or pressure plate sufficiently to leave an indent mark 

were considered as probably detonated. Mines that were struck on the body causing 

penetration, break up or destruction were considered as only possibly detonated but 

probably destroyed. When the results were analysed, mines were considered to have 

been cleared if they met one or more of the following criteria: 

• Probable detonation i.e. if the fuse had been hit or the mine had taken more than 

three hits. 

• Removed from the path of the clearance vehicle. 

• Break up or destruction of the mine. 

These criteria have been taken from the previous trial report on Aardvark dated 

December 1995². 

DERA/LWS/LSAA/TRD000603/1.2 Page 1 of 77

2 Aim 

3 Scope 

Page 2 of 77 

The aim of the trial was to test the potential of the new upgraded version of the Aardvark 

Flail to clear anti-tank mines from roads, tracks and cross-country. The tests were carried 

out under the headings Transportability, Mobility and Performance. There were no 

Survivability tests conducted on this trial. 

The Aardvark Mk IV was evaluated on its performance and its ability to clear 

representative AT mines. The standard tests for Transportability were carried out; 

General Dimensions, Weight and Approach/Departure angles. Mobility was assessed by 

measuring the turning circle and results from the cross-country and alpine tracks. The 

Performance criteria encompassed an assessment of reliabilty, running costs and ease 

of maintenance, additional tests included encountering an inert minefield. Although 

Survivability was not assessed, it is the understanding of DERA that the Mk IV has been 

independantly tested against live mines in Jordan and by the Royal Netherlands Army 

Ammunition Branch. 


Rear 

Front 

Figure 3-1; Aardvark Mark IV 


4 Improvements 


This section outlines the specifications given by Aardvark Clear Mine on the 

improvements to the Aardvark Mk IV in comparison to the Mk III.³ 

Mark IV Mark III 

Cab Assembly 10mm fully armoured 10mm fully armoured 

56mm armoured glass with 56mm armoured glass with 

polycarbonate liner protection polycarbonate liner protection 

Sound proofed inner walls Sound proofed inner walls 

Air conditioner with 

Air conditioner with 

temperature controls 

temperature controls 

Heater unit Heater unit 

Filtered fresh air intake with Filtered fresh air intake with 

booster fan. 

booster fan. 

Console with all controlling Console with all controlling 

functions for prime mover and functions for prime mover and 

flail operation. 

flail operation. 

Lower underside of cab angled Lower underside of cab angled 

profile to provide maximum profile to provide maximum 

blast force deflection 

blast force deflection 

Power Train New Holland TM165 ‘T’ 

(turbocharged) 

Ford 8210 Series 

Brake Horse-Power 165 115 

Displacement: 7472cm³ 6572cm³ 

Transmission: 16 forward and 16 reverse 32 forward and 16 reverse 

gears (Plus creep options in all 

gears) 

gears 

Power Take Off: Three selectable speeds for 

flail drive and attachments 

Power take off for flail drive 

Fuel Tank: Equipped with explosafe Equipped with explosafe 

Brakes 4 wheel braking with inhibitor 

switch to front wheel brakes 

when flailing. 

Parking brake 

Power Train 

Compartment 

Full length 10mm armoured 

belly plate, 6mm plate hood 

2 wheel braking on rear 

(tracked) axle 

Full length 10mm armoured 

belly plate, 6mm plate hood 

Flail Unit 10mm box section A-frame 

New chain configuration 

8mm box section A-frame 

Rotor Bearings: Steel (Mk III Bearings were 

prone to shattering) 

Cast Iron 

Rotor Speed: 300 rpm 220 rpm 

Table 4-1; Improvements 


4.1 Additional Alterations: 

4.1.1 The V-belts supplying drive to the rotor have been upgraded. 

4.1.2 The width of each track has been narrowed from 660mm to 508mm to improve the skid 

steer capability. 

4.1.3 An air compressor has been fitted for pneumatic tool use and to assist in cleaning the 

machine. 

4.1.4 The oil coolers are removable for cleaning (with the pipework still attached) 

4.1.5 The size of the radiator and air intake have been increased to compensate for the larger 

engine and to allow Aardvark to operate in higher temperatures. 


5 Trials Methodology 

5.1 General 


The trial was carried out and managed by the Countermine Warfare team from DERA 

Chertsey. Details can be found in the Trial Plan, Ref: DERA/LSAA1/CMW8/13/03/01/01 

Results and observations were recorded daily and supported by still photography and 

video recordings. 

5.1.1 Performance, Mobility and Transportability 

This included measuring of major dimensions, handling and mobility of the machine, 

safety, followed by encountering mines in an inert minefield. 

5.1.2 Survivability 

5.2 Sites 

There were no survivability tests carried out in this set of trials . 

The site used for this trial was DERA Bagshot. 

5.2.1 DERA Bagshot 

The DERA Bagshot test track is split into three sections: 

Rough Road Course 

This is a 3.7 mile rough road course suitable for wheeled vehicles of all sizes (including 

loaded tank transporters). ‘Rough Road’ indicates a graded, compacted surface of 

flintstones (up to 6 inches in diameter) with a clay and sand binding. With use the road 

becomes rutted and covered in potholes and this combination provides a very severe 

test for suspension systems and tyres. 

Alpine Course 

This is a narrower, steeper (up to 1-in-2.7 gradients) 3.5 mile circuit constructed with the 

same mixture of flint, sand and clay. 

Cross Country Area 

There is a central Cross-Country driving area, approximately 1 km square, consisting of 

sand and mud between heather and small trees. This area was not used for the trial. 

5.3 Procedures 

5.3.1 The trial was conducted using a range of test lanes and slopes available to measure 

performance. 

5.3.2 The inert minefield encounter used inert model AT mines as targets. These were laid to a 

specific pattern and depth for each test run. 

5.3.3 Details of the test procedures and results are shown in the following pages. 


6 Test Procedures and Results 

6.1 General 

6.1.1 For the purposes of the trial the ‘cab’ end of Aardvark will be defined as the front and the 

flail end will be defined as the rear of the vehicle, i.e. the machine flails minefields in 

reverse. (See Fig 3.1) 

6.1.2 Test procedure and performance sheets were issued for each performance and test. 

These test performance sheets have been published separately and are available from 

DERA. A summary of the tests is shown in Table 6.1. The description, summary of 

results and comments/observations of each test are detailed on the following pages. 

6.2 Results 

Test Description Test No. 

Weight & General Dimensions a) Wheelbase A1/1 

b) Approach Angle A1/1 

c) General Dimensions A1/1 

d) Axle Weights A1/1 

Handling & Mobility a) Turning Circle A2/1 

b) Slopes A3/1 

c) Flailing Depths A4/1 

d) Obstacles A5/1 

e) Rough Terrain A6/1+2 

Inert Minefield Encounter A7/1 - 9 

Table 6-1; Summary of Tests 

The results will be presented in order of category and not necessarily in chronological 

order. The catagories are; Transportability, Handling & Mobility and Performance. 


6.3 Transportability 


This category of tests is used to assess the factors effecting the transport of the 

equipment. 

6.3.1 Test A1 General Dimensions (Data sheet A1/1) 

6.3.1.1 Description 

6.3.1.2 Results: 

The vehicle was parked on solid flat level ground and the following dimension were 

obtained: 

• The overall length, width and height of the main body. 

• The wheelbase of the main body and trailer. 

Figure 6-1; Plan view of Aardvark 

Test Measurement Result 

Principle Dimensions Overall Length of vehicle 8.000m 

Overall width of vehicle 3.505m 

Overall Height:- Top of Air Intake 3.460m 

Air Transportable 2.579m 

6.3.1.3 Comments & Observations 

Table 6-2; Principle Dimensions 

Transportability: The machine was capable of being driven onto and off a low loader 

transporter and it can be made air-portable with the removal of the air filter and flail arm. 


Figure 6-2; Measuring the height of Aardvark 


6.3.2 Test A1 Weights (A1/1) 

6.3.2.1 Description 



Individual compression load cells were positioned on solid flat level ground and the 

vehicle driven onto them to measure the weight of each wheel station of the main body. 

An average from 3 measurements was taken. 


Weight Gross Weight 15377kg 


Table 6-3; Weight 

This is a minimum value for the gross weight (total operational weight, fully fueled up) 

due to the load cell on wheel station 4 (WS4) being overloaded. It can be compared with 

the dry weight specified by Aardvark Clearmine in Annex A. 


Figure 6-3; Using load cells to weigh Aardvark 


6.3.3 Approach Angle (A1/1) 

6.3.3.1 Description: 



The vehicle was parked on solid flat level ground. The end of a flat bar was placed on the 

ground parallel to the centre of the front road wheel and the bar raised until it came into 

contact with the vehicle frame. The angle between the ground and the bar, the approach 

angle was then measured using a clinometer. This process was repeated for the 

following 


Approach Max. Forward Approach Angle 26º 07’ 

Angles Reverse Approach Angle: Airfield Mode 30º 42.5’ 

Rough Terrain Mode 32º 17.5’ 

Transportation Mode 32º 41.5’ 

Table 6-4; Maximum Approach Angles 


No Comment. 


Figure 6-4; Measuring the Approach Angle with a straight edge and clinometer 


6.4 Handling & Mobility 


This category is concerned with the manoeuvrability and speed of the machine. 

6.4.1 Turning Circle (A2/1) 



Aardvark was required to turn in as smaller radius as was possible both anti-clockwise 

and clockwise, and in the forward and reverse direction. (For a definition of front and rear 

of Aardvark see figure 3.1) 


Direction Average Diameter 

(metres) 

Forward Left Hand Lock 10.68 

Reverse Left Hand Lock 10.37 

Forward Right Hand Lock 11.40 

Reverse Right Hand Lock 10.68 

Table 6-5; Turning Circle in forward and Reverse 

Aardvark performed adequately on the gravel area set aside for this exercise. 

Figure 6-5; Aardvark on the gravel used for a Turning Circle 


Figure 6-6; Turning Circle 


6.4.2 Slopes (A3/1) 




Aardvark was required to climb a series of sloped compacted gravel tracks. 


Direction Gradient 

Forward Greater than 1 in 2.33 (23º12’) 

Reverse Greater than 1 in 2.33 (23º12’) 

Table 6-6; Maximum gradient climbed 

Driving forward (driving tyres first) steering traction was lost on the tyres but steering was 

maintained by use of tracks. This did not occur in the reverse direction. 


Figure 6-7; Aardvark climbing Birch Up Road (Grad. 1 in 3.5) 


6.4.3 Flailing Depths (A4/1) 



Flailing Depth mm 


Aardvark flailed over a marked out flat area of track at varying speeds and flail depths. 

See Figures 6.9 to 6.17 

600 

500 

400 

300 

200 

100 

0 


Speed m/hr Average Depth mm 

67 528 

100 430 

150 265 

200 275 

300 163 

600 100 

900 102.5 

1200 45 

Table 6-7; Table of Flailing Depth against Speed 

Aardvark Mk4 Flailing Depths 

y = 14450x -0.7751 

0 200 400 600 800 1000 1200 1400 

Speed m/hr 

Figure 6-8; Graph of Flailing Depth against Speed 

These results can be compared with those in Appendix A (Note: Flail depths will vary 

with different terrain types). The graph includes a line of best fit which is intended to 

highlight the overall trend. 


Figure 6-9; Speed = 67m/hr, Depth = 528mm 

Figure 6-10; After flailing at 100m/hr 













Figure 6-17; Measuring Level used 


6.4.4 Obstacles - Water (A5/1) 




Aardvark was sent into a water filled 450mm deep gully in flailing mode. See Figures 

6.18, 6.19. 

Aardvark started flailing at 200m/hr but to get better water penetrationl speed was 

reduced to 67m/hr. At 67m/hr a flail speed of 1970rpm was held. 


There was no way of telling whether the flails were hitting the bottom although rocks and 

a tin can were thrown up. 


Figure 6-18; Aardvark entering the water filled gully 

Figure 6-19; At the end of the water run 


6.4.5 Rough Terrain (A6/1) 




A 100m strip of heavily vegetated/wooded land on a side slope was set out. 

A simulated minefield was laid in the first 5m and a tree was situated in roughly halfway 

along the strip (~300mm thick trunk). See figures 6.20 to 6.23. 

Aardvark started flailing at 200m/hr this was flail speed was cutting too deep, so after a 

few metres the speed was increased to 300m/hr. This changed the flail depth from an 

average depth of 275mm to an ayerage depth of 163mm. 

The angle of the side slope at various points is as follows. 

• At the end of the minefield = 10º 10’ 

• ½ way across = 5º 

• ¾ way across = 14º 14’ 


Aardvark cleared the minefield and reduced the 2.5m high foliage to fine mulch. It 

knocked the tree over and reduced half of it to mulch. 

The TMA-3 AT mine simulant in figure 6-23 has been hit several times, one of the fuses 

has been split. It was considered that this would have probably detonated or been 

incapacitated. 


Figure 6-20; Foliage and terrain encountered in test area 

Figure 6-21; Aardvark at the start of the run 


Figure 6-22; Aardvark at the end of the run. Note the large debris thrown from the flail 


Destroyed 

Mine Case 

Figure 6-23; Test run after clearance, compare with Figure 6-14 




6.4.6 Rough Terrain (A6/2) 




A 750m strip of partially vegetated/wooded track on a slope was set out (an overgrown 

firebreak). 

This test was designed to test Aardvark’s brush clearance capability. 

Aardvark flailed at varying speeds throughout this test according to what the terrain 

permitted. 

The angle of the side slope at various points is as follows. 

• Start = 16º 03’ 

• At ½ way:- downhill = 20º 07’, Side slope = 18º 15’ 


The flail threw stones, branches and debris high in the air (~30m) depositing it over a 

wide area. 


Figure 6-24; Test run before clearance 

Figure 6-25; Test run after clearance, 



Figure 6-26; View of Aardvark flailing the fire-break. 




6.5 Performance 

This section of the report is concerned with the fitness for purpose, reliability, running 

costs and ease of maintenance. 

6.5.1 Inert Minefield Encounter (A7/1) 


A minefield consisting of inert filled AT mines was laid in a 6m by 3m area. Aardvark was 

set to clear it. The position of the minefield was on White Hill and had a gradient of 1 in 

6.0. Aardvark flailed uphill at a speed of 150m/hr. 

6.5.1.2 Results: Run 1 see figures 6.27 to 6.32 

Figure 6-27; Plan of Run 1 

Mine No. Mine Type Outcome 

1 TMA-3 Partly damaged – 1 fuse removed & Outside flail width 

2 TMA-2 Destroyed 


4 GIAT Minotaur Hit 3 times, left in spoil on centreline 

5 GIAT Minotaur Hit 2 times, left in spoil on left-hand side 


Table 6-8; Minefield Data Run 1 

Although mine No.1 was partly damaged since one fuse was hit it would have probably 

detonated, figure 6.30. It can be assumed that the other four mines would have been 

deactivated. 



Destroyed 

Mine Case 

Figure 6-28; Layout before Run 1 

Figure 6-29; Test area after Run 1 



Edge 

of Flail 

width 

Figure 6-30; Although just outside flail width (shown by pin above the mine) one fuse was 

removed. 

Figure 6-31; Giat mine with evidence of the flail encounter 


GIAT 

buried in 

spoil 

Figure 6-32; Position of mines after Run 1 






set to clear it. The position of the minefield was on White Hill and had a gradient of 1 in 

13.7. Aardvark flailed uphill at a speed of 150m/hr. 






4 GIAT Minotaur Hit 4 times, thrown 25m behind vehicle to RHS 



The GIAT Minotaur would probably been destroyed or detonated. 




Destroyed 

Mine Case 

Figure 6-34; Layout of Run 2 

Figure 6-35; Test area after Run 2 


Mine Case 

Fragments 


Figure 6-36; GIAT mine 25m behind Aardvark 

Figure 6-37; Spoil after run 2 








set to clear it. The position of the minefield was around a corner on White Hill and had a 

gradient of 

1 in 13.7. Aardvark flailed uphill at a speed of 150m/hr. 

6.5.3.2 Results: Run 3 see figures 6.38 to 6.42. 





4 GIAT Minotaur Hit 4 times 







Figure 6-39; Layout of 3 

Figure 6-40; Aardvark flailing Run 3 



Figure 6-41; End of Run 3 

Figure 6-42; Spoil after Run 3 








set to clear it. The position of the minefield was on Alpine Way and had a gradient of 




1 TMA-3 Partly Damaged 



4 GIAT Minotaur Hit 2-3 times 








Figure 6-45; Aardvark just passed Run 4, GIAT in foreground 






set to clear it. The position of the minefield was on Alpine Way and had a gradient of 







4 GIAT Minotaur * 

5 GIAT Minotaur * 




Run stopped before the last two mines due to a communication error. The blast plate 

was used as a dozer to fill the flail damaged surface, see figures 6.49. 


Run stopped before these mines 


Figure 6-48; End of Run 5 



Figure 6-49; Aardvark using the blast plate to fill in the scar left from the run 

Spoil 

Figure 6-50; Spoil left after Run 5 








set to clear it. The position of the minefield was on Birch Up on the Alpine Way and had a 






2 TMRP-6 Destroyed 







The pencil in Figure 6.55 has been placed along the edge of the flail line. The GIAT 

Minotaurs would probably been destroyed or detonated. 





Pencil on 

edge of 

flail line 


Figure 6-54; GIAT in spoil after several hits 

Figure 6-55; Buried TMA-3 that partly fell outside of the flail width 








set to clear it. The position of the minefield was on Birch Up on the Alpine Way and had a 





1 TMA-3 Outside Flail path 








The GIAT Minotaur would probably been destroyed or detonated. Typical dust profile 

shown in figure 6.58. 



Figure 6-58; Dust profile when flailing 



Figure 6-59; GIAT in the foreground, broken mine casings in the background 


Figure 6-60; TMRP-6 and TMA-2 

Figure 6-61; TMA-3 outside flail width 






set to clear it. The position of the minefield was on Birch Down heading downhill on the 

Alpine Way and had a gradient of 1 in 2.7. Aardvark flailed uphill at a speed of 200m/hr. 



1 TMA-3 Outside Flail path 








At start-up the flails on the RHS were seen to oscillate in a left to right motion causing a 

100mm rut to be formed, this rut did not adversely affect the clearance 


een destroyed or detonated. 

. The GIAT Minotaur would probably 




Figure 6-64; Aardvark having cleared Run 8 



Figure 6-66; TMA-3 outside flail width 








set to clear it. The position of the minefield was in a 215mm deep puddle on the flat run 

onto the cross-country track and was on flat horizontal ground. Aardvark flailed at a 

speed of 200m/hr. 

6.5.9.2 Results: Run 9 








The flail speed dropped from 300 to 260 rpm. 






Figure 6-69; Aardvark flailing in ~200mm of water 


Figure 6-70; Run 9 after flailing 

Figure 6-71; State of the mines after flailing 



Figure 6.72 below summarises the results of all Inert Minefield Encounters. 

Mines Laid End State of Mines 

Buried Flush Surface Total Hit Missed Outside width of 

Flail 

TMA-2 0 2 5 7 7 0 0 

TMA-3 11 5 2 18 16 0 2 

TMA-5 0 2 0 2 2 0 0 

TMRP-6 0 0 3 3 3 0 0 

GIAT 15 15 13 0 2 

45 41 0 4 

Figure 6-72; Summary of Mines Laid/Cleared 


6.5.10 Running Costs and Ease of Maintenance 


6.5.10.2 Results: 

Throughout the trial maintenance needs were recorded and repair times were noted. 

Aardvark was run for a total of 12 hours during the week. 

2 sets of chain were replaced during the week ( 1 hour to change). 

The track pads were changed in 1hour. 

It was stated that the flail could be removed from the prime mover in 20 minutes. 

100 litres of fuel was used. 

1 fuse was replaced 


The Aardvark flail appeared to be an easy machine to service and maintain with a well 

thought out maintenance schedule. See Appendix B 


7 Conclusions 

7.1 The test track at Bagshot proved to be an adequate site for the trial. However, there are 

certain limiting factors involved in carrying out a trial on one site only over a short time 

period, such as only being able to flail in one type of soil (flint/sand/clay mix). A large 

amount of data was gathered from the inert minefield clearance tests, although due to 

the small sample size less emphasis can be placed on the statistics of this test. Aardark 

was weighed using portable vehicle load cells. Certain inaccuracies were encountered 

because the vehicle exceeded the maximum readable load on one of the wheel stations. 

7.2 The Aardvark Mk IV is easily transportable, has a good turning circle for the size of the 

vehicle and has good manoeuvrability that is only limited by the skill of the operator. It is 

air portable when the flail and air filter are removed. Detracting from its transportability is 

its weight. At over 15 tonnes and 3505mm wide, certain limitations of where Aardvark 

can be transported on land must be accepted. If the role of the Aardvark Mk IV is 

predominantly clearance of anti-tank mines then this should not be a problem since it has 

the capability of going where a tank can go and therefore where anti-tank mines would 

most likely be laid. Aardvark has adequate approach and departure angles for most 

transporter trailers. 

7.3 From the Forward speed/Flail depth plot (Fig 6.8) it can be seen that the optimal speed 

to reach a depth of 300mm (NATO quoted average depth to base of a buried anti-tank 

mine) was between 150 & 200m/hr on this terrain. 

7.4 Although the driver’s view of the road was adequate looking towards the flail, it was 

greatly reduced by the engine cowling and the flail unit on the front. This drawback is 

partly overcome by having a crewmember sitting opposite the driver who is able to look 

down the other side of the vehicle. 

7.5 Aardvark proved its worth as a brush and vegetation clearer. It was able to clear through 

dense shrub and knocked over a tree of diameter 350mm and 7m high. However, it did 

throw a lot of debris (of greater than 250mm major dimension) over a large area. This 

raises the issue of contamination of areas that either have been cleared already or 

weren’t contaminated in the first place. 

7.6 Aardvark performed well clearing the inert mines from on the flat and on slopes. The 

overall percentage clearance rate was in line with the UN expected standard of 

clearance. Due to the small sample size less emphasis can be put on the 

7.7 statistics of this test: if Aardvark had missed one mine the clearance rate of 100% would 

have dropped to 97.7%, below the UN standard. Since the main aim of the trial was to 

evaluate the increased power of the Mk IV it can be said that there was no noticeable 

drop in flail performance between flailing on the flat and on the steepest hill at DERA 

Bagshot (1 in 2.7). 

7.8 The water obstacle test was an interesting test and, although not conclusive, showed 

that Aardvark Mk IV had the power and potential to clear mines in water 450mm deep. 

7.9 During the trials maintenance checks were carried out and two sets of chains and a set 

of track pads were removed and changed with ease. It is evident that a lot of effort has 

been directed toward making the Mk IV maintenance friendly, with the inclusion of an air 

compressor for power tools and cleaning of the machine and easily accessible parts 

such as radiators and air filters. 



8 Recommendations 

8.1 The driver’s lack of visibility was seen as an area for improvement. Use of CCTV 

cameras on the passenger side and perhaps one camera facing towards the flail from a 

roof mounted position incorporating wide-angle visibility could improve this. 

8.2 It is appreciated that by their very nature armoured vehicles are heavy and that the 

Aardvark flail has been proven to be well engineered against blast and fragmentation 

damage in the field. However, reduction of the overall weight of the Mk IV without 

detracting from it’s structural integrity would; 

• Reduce transport costs 

• Increase the areas that Aardvark could gain access to. 

• Reduce fuel costs 

8.3 The guard over the top of the flail could be extended with a sacrificial large holed mesh 

to stop the larger pieces of debris from being thrown out. 


9 References 


1. Project No. 6984.07.4010 Vulnerability study mine-clearing system Aardvark and 

operating personnel. Maj ir. P.J.M de Veer. 

2. DRA/LSF3/CR95/042/1.0 Operation HAMDEN Countermine Equipment Trials for 

Newly Specified Terrains. N Goulton – Dec 95 

3. Aardvark Clear Mine publicity brochure. 


A MK III AND MK IV RELATED PERFORMANCES 

MKIII MK IV 

ENGINE TYPE:- FORD 8210 SERIES NEW HOLLAND TM165"T” 

BHP:- 115 165 

PTO OUTPUT:- 540RPM 1000RPM 

ROTOR SPEED:- 220RPM 300RPM 

BRAKES:- MULTI PLATE (TRACK ONLY) (TRACK) MULTI PLATE 

(CAB WHEEL) DRUM 

FLAIL DRIVE:- BELT (GATES MAKE) BELT (ARAMID MAKE) 

STEERING:- HYDROSTATIC HYDROSTATIC 

WEIGHT:- 13,624KG 15,180KG 

BATTERY:- 12VOLT 12VOLT, 2x720GCA 

FUEL:- DIESEL, 16LTR PER HOUR DIESEL, 23LTR PER HOUR 

GRADIENTS:-34% CLIMB, 25%SIDE SLOPE 34% CLIMB, 25% SIDE SLOPE 

TRANSMISSION:- MECHANICAL 32 FORWARD & MECHANICAL 16 FORWARD 

16 REVERSE SPEEDS & 16 REVERSE 

(PLUS CREEP OPTIONS IN ALL GEARS) 

DIGGING PERFORMANCES & FLAILING SPEEDS 

MK III:- 900MTR PER HOUR = 50mm TO 100mm DEPTH 

MK IV:- SPEED APPROX DEPTH 

1100m per hour 100mm TO 150mm 

500m per hour 200mm to 250mm 




B Summary of the Maintenance Schedule 

Interval Servicing Task 


FLAIL 

PRIME 

MOVER 

CHECK 

CLEAN 

LUBE 

LOC 

EVERY HYDRAULIC TRANSMISSION GEARBOX OIL X X X 

10 

HOURS HYDROSTATIC STEERING PUMP X X X 

OR 

DAILY RADIATOR COOLING LEVEL X X X 

ENGINE OIL LEVEL X X X 

BRAKES, CLUTCH & DIFFERENTIAL FLUID 

LEVELS 

PRE-CLEANER AIR FILTER X X 

NB:- CLEAN ONLY WHEN WARNING LIGHT ON 

DASH ILLUMINATES 

AIR PRE-CLEANER BOWL X X 

DOOR FAN BREATHER FILTER X X 

CHANGE 

ADJUST 

X X X 

GREASE PTO SHAFT (2 NIPPLES) X X X 

GREASE MAIN FLAIL PIVOT BEARINGS X X 

(4 NIPPLES) 

WINDSCREEN WASHER WATER X X X 

DIESEL FUEL X X X 

WHEEL NUTS (FRONT AXLE) X X X 

TRACKS X X X X 

HIGH TENSION DRIVE (HTD) BELTS (2 OFF) X X X 

FLAIL DRIVE BELTS (10 OFF) X X X 

TENSION LOCKOUT LINKS (8 OFF) X X X 

CHAINS, TIPS & INTERLINKS (72) X X X 

HYDRAULIC PIPES X X X 



DERA/LWS/LSAA/TRD000603/1.2 Page 75 of 77 

FLAIL 

PRIME 

MOVER 

CHECK 

CLEAN 

LUBE 

LOC 

CHANGE 

EVERY 10 HOUR SERVICE IS CARRIED OUT IN 

50 CONJUNCTION WITH THIS SERVICE 

HOURS DRIVE SPROCKET SECURING NUTS X X X 

OR 

WEEKLY TYRES - FOAM FILLED X 

CLUTCH PEDAL FREE PLAY X X X 

BATTERY ELECTROLYTE LEVEL X X X 

FUEL SYSTEM WATER & SEDEMENT 

SEPARATOR 

X X 

TRANSMISSION/REAR AXLE OIL LEVEL X X X 

FRONT WHEEL SPINDLES/AXLE PIVOT X X X 

(5 NIPPLES) 

BRAKES CROSS SHAFT (3 NIPPLES) X X X 

HAND BRAKE CABLES (2 NIPPLES) X X X 

CLUTCH CROSS SHAFT (1 NIPPLE) X X X 

GEAR CHANGE LEVERS (6 NIPPLES) X X X 

DOOR HINGE PINS (2 NIPPLES) X X 

EVERY 10 & 50 HOUR SERVICE IS CARRIED OUT IN 


HOURS 

ENGINE OIL & FILTER X X 

HYDROSTATIC STEERING OIL LEVEL X X X 

HYDRAULIC OIL FILTERS X X 

HYDRAULIC OIL X X X 

GEARBOX OIL X X X 

TRACK CARRYING FRAME (4 NIPPLES) X X X 

FOOT BRAKES X X X 

HANDBRAKE X X X 

HRC COUPLING X 

ADJUST



FLAIL 

PRIME 

MOVER 

CHECK 

CLEAN 

LUBE 

LOC 

CHANGE 

EVERY 10, 50 & 200 HOUR SERVICE IS CARRIED OUT 

IN 


HOURS 

FRONT WHEEL BEARINGS X X X 

FRONT WHEEL HUBS/GREASE X X 

VALVE TAPPET CLEARANCE X X X 

FUEL INJECTORS X 

FUEL FILTER X 

STARTER MOTOR PINION X X X 

EVERY 10 & 50 HOUR SERVICE IS CARRIED OUT IN 


HOURS 

TRANSMISSION/REAR AXLE OIL X X 

HYDROSTATIC STEERING OIL FILTER X X 

GEAR BOX OIL X X 

ANNUAL ENGINE COOLANT 

AS 

REQUIRED GENERAL SERVICING X X 

ADJUST 

DERA/LWS/LSAA/TRD000603/1.2 

X 

TEST 

X

Distribution list 

Ms A Doherty DFID 1 

Mr D Sadler Aardvark Clear Mine Ltd 2 

Technical Manager, 

Engineer Equipment 

DERA 3 

Counter Mine Library DERA 4 

Main Library DERA 5 

DRIC 6 

Copy 

Spare (X4) DERA 7 - 10 


Report documentation page 

1. Originator's report number: DERA/LWS/LSAA/TRD000603 

2. Originator's Name and Location: Mr C A Leach Counter Minewarfare, DERA 

Chertsey 

3. MOD Contract number and period covered: TBA 

4. MOD Sponsor's Name and Location: N/A 

5. Report Classification and Caveats in use: 6. Date written: Pagination: References: 

UNCLASSIFIED COMMERCIAL February 2001 xii + 77 3 

7a. Report Title: Evaluation of Aardvark Mk IV Flail 

7b. Translation / Conference details (if translation give foreign title / if part of conference then give 

conference particulars): 

7c. Title classification: UC - COMMERCIAL 

8. Authors: Mr. C A Leach 

9. Descriptors / Key words: Aardvark, Flail, Humanitarian De-mining, DFID, 

DERA Bagshot 

10a. Abstract. (An abstract should aim to give an informative and concise summary of the report in up to 

300 words). 

Aardvark Clearmine Ltd have upgraded their Aardvark flail unit, a system that has an 

already proven track record for detonating mines and removing UXO and debris from 

mine affected land. 

DERA undertook testing and evaluation of the system on behalf of DFID (the 

Department for International Development). The machine offered for trialing was the MK 

IV Aardvark Flail, which performed well throughout the trial completing all the tests 

adequately. 

Overall, the objectives of the trial, testing the improved power and performance, were 

achieved by demonstrating the concept of using a flail to clear mines and dense foliage 

from various terrain. As with most mechanical clearance devices the application of this 

equipment has to be in the context of the mine threat, type of terrain, climatic and 

environmental conditions and of the overall demining operation. 

10b. Abstract classification: UC - COMMERCIAL FORM MEETS DRIC 1000 ISSUE 5

Evaluation of Aardvark Mk IV Flail - gichd

Create successful ePaper yourself

Delete template?

Save as template?