Flaws of Arjun:
1. Main sight weakspot - General armour of front turret is estimated at 735 mm but area behind weakspot is rated at only 400 mm of armour by Western Analysts.
2. Side Turret armour placement - 30 degree Safe Manoeuvring angles are safe but beyond that, composites are weak and at least 2 empty tool boxes are there instead of armour. First block of armour is rated at 300 mm+ comparable to Western tanks but area behind tool boxes is a pitiful 60 mm.
3. Main gun - The biggest mistake was going for a rifled weapon. While Arjun's gun is comparable in strength to smoothbore weapons, the barrel wears out much quicker. However, the gun has potential for an extreme 800 mm long rod penetrators to be used.
Solutions:
Problem 1. Arjun Mk-II has already solved a part of the problem by adding NERA and thicker Kanchan plate after main sight.
Problem 2. Tool boxes can be removed and composite filler added - NERA might be placed OVER tool boxes.
Problem 3. Is bound to be solved in FMBT. (Arjun MK-III) DRDO has stated that smoothbore 120 mm weapon development has begun and rifled gun is bound to be replaced.
Otherwise license for Rh 120 L/44 or L/55 or even Rh NPzK 140 L/48 license can be purchased. Possibility of Ukrainian "Vitiaz" 125 which is superior to 2A46M and "Bageera" much superior to L/55 are also on the table - Ukraine has offered to sell 6TDF series 1500 HP and 1800 HP in development engines for Arjun and T-90MS tanks - if such trade offer is accepted, there is possibility of purchase of Ukrainian armament.
Flaws of Al-Khalid
1. ERA coverage: As in tanks of Chinese origin, ERA coverage over glacis is close to 70%. There is 40-50% possibility of 3BM42 Mango rounds used by T-90 and ARDE 120 round penetrating glacis if area without ERA is hit.
Since Indian T-90MS has Russian T-90A modifications, longer rounds such as 3BM42M Lekalo, 3BM59/60 Svinets-1/2 which may be supplied to India in the future have assured penetrations. Also able to penetrate glacis is Ukrainian 125 mm round "Vityaz" AP which is rumoured to have 750 mm penetration.
2. Roof armour: A moderate portion of roof armour slopes onto frontal turret armour in Chinese designs Type 90-II, 85-II and 96. Al-Khalid has also been observed with this flaw. In Soviet and Chinese school of tank design, roof armour is paltry, sometimes a mere 50 mm. As such, Al-Khalid is in risk of being penetrated frontally by even BMP-1's 73 mm and BMP-II's 2A42. Only Type 99A2 has been observed WITHOUT this flaw.
3. Side turret armour placement: In Soviet school of design, the turret was small and well angled but had poor protection on the sides which would not be exposed frontally. In Chinese school of design, the turret was larger and resembled Western turrets but had Soviet style armour placement - worst of both worlds. The side turret armour of T-90 itself is rated at only 140 mm without ERA. Al-Khalid seems to have similar placement to Type 85 and 90 which is to say poor. This flaw has been partially fixed by Chinese in Type-99A2 by uparmouring sides slightly and adding heavy ERA.
Solutions:
Problem 1. Simple, increase ERA blocks and rethink placement of the blocks.
Problem 2. Complete redesign of turret is required to remove this problem. Partially fixed by Pakistani designers by adding more ERA to the sloped part.
Problem 3. Redesign of turret - but weight will increase by one or two tons which may require redesigning of suspension.
The only clear advantage of Al-Khalid over Arjun is smoothbore weapon.
The only clear advantage of Arjun is hydrogas suspension which reduces weight of tanks by 1 or 2 tons compared to torsion bar.
Torsion bar provides comparable cushioning to hydrogas but must weight much more.
Arjun MK-III is perceived to receive 120 mm or 140 mm smoothbore weapon with 700+ mm penetrating rounds. DRDO has stated that development of 650 mm penetrating APFSDS round for old rifled gun itself is complete. Pakistan must change armour placements on hull and redesign turret to prevent frontal penetration.
As of now, both Arjun and Al-Khalid cannot penetrate each other frontally from other than above-mentioned weakspots.
Perhaps Al-Khalid-2 will receive long rod penetrators and hydrogas suspension to evenly match future Arjun.
It needs to become more interesting
Generally saying, Arjun has more potential for upgrades without turret redesign. It is expected that Chinese designers who are rectifying problems in their tanks will help Pakistan in design of future Al-Khalid variants.
The sub-continent is getting competitive.
I hope this cleared it all up.
Regards,
Keshav