- Yes
- No
M163A1 PIVADS at Fort Irvin, image via AFVDB
The M163 Product Improved Vulcan Air Defense System (PIVADS) is an improved version of the M163 VADS produced in the 1980s. By gaining a better fire control system and improved ammunition (including Mk 149 APDS and M940 MPT-SD), the PIVADS provides superior anti-air and anti-armour capabilities, making it a viable successor (or even replacement) to the VADS in the US tech tree.
History and Design
The PIVADS was a simple upgrade kit for the old VADS, mostly focusing on improving gunner effectiveness by providing more sophisticated electronics. The disturbed-line-of-sight was replaced with a director sight, and a new digital fire control computer was linked to the radar. The radar itself was replaced with the AN/VPS-2A. However, it’s unclear what, if any, differences it has from the old AN/VPS-2 apart from the addition of a radome (I’m also unsure whether this was a PIVADS-specific upgrade, or one performed during the M163A1/M163A2 upgrades, based on which PIVADS was created). The PIVADS also allegedly gained access to the Mk 149 APDS and later the M940 MPT-SD; see the next section “Ammunition discussion” for more details. Otherwise, the vehicle was unchanged from the original VADS.
The Lockheed Electronics Company, a division of the Lockheed Corporation, was contracted in 1982 to produce 285 PIVADS upgrade kits for both self-propelled and towed VADS versions. Deliveries began in 1984 and were completed by 1988.
Ammunition discussion
The ammunition available to the M163 VADS, and hence, by extension, the PIVADS, has been the subject of extended discussion on this forum. The most critical issue is whether the VADS had access to the Mk 149 APDS, originally developed for the Phalanx CIWS.
There are numerous secondary and primary (specifically, General Dynamics brochures) sources stating that the Mk 149 was compatible with all Vulcan gun systems. Additionally, all secondary sources about the PIVADS also state that it was equipped with APDS to extend its effective range to 2600 m. However, all official sources make no mention of the PIVADS being equipped with APDS, except for an “official-looking” document I found on the Internet Archive titled “Vulcan Mk 149 Stinger”, which allegedly is an “Excerpt from military paper on upgrades on the VADS/PIVADS system and Air To Air Stinger launcher”. I suspect that while compatible, APDS might not have been issued to VADS/PIVADS units due to cost reasons.
Another ammunition option that’s less discussed is the M940 MPT-SD (multi-purpose, tracer, self-destructing) round. It contained 4 g of Comp A4 and had a hardened steel body and delayed fuse, essentially a SAPHE round. It is said to extend the effective range of the VADS/PIVADS to 2000 m, thanks to reduced drag and superior ballistics. Testing has shown that it can penetrate 3/8 inches (9.5 mm) of RHA at 500 m. Using data from a Northrop Grumman brochure, it should have about 32 mm of penetration at point-blank range according to the Jacob de Marre formula.
This round was available to the VADS/PIVADS, as stated by TM-43-0001-27 (which also says that it received its type classification on March 13, 1989, just shortly after the PIVADS conversion ended) and the General Dynamics brochure, although similar to the APDS situation, official documents and manuals do not mention it either. Strangely, TM-43-0001-27 says that it was meant to replace the M246 HEIT-SD as the “primary air defense cartridge” for VADS/PIVADS.
Given the above information, and in the interest of differentiating the PIVADS from the old VADS, I recommend that the PIVADS be implemented with both Mk 149 APDS and M940 MPT-SD ammunition.
Specifications
As PIVADS was upgraded from existing VADS vehicles, specifications remained largely the same. Any specifications not mentioned here are presumed to be identical. See the in-game M163 model for more details.
Crew: 4
Armour: 12-38 mm
Armament: 20 mm M168 cannon
Ammunition: Mk 149 APDS, M940 MPT-SD, M246 HEIT-SD, M56 HEI, and other Vulcan-compatible ammunition
Engine: General Motors/Detroit Diesel 6V53, 212 hp
Max speed: 64 km/h
Sources
- “Jane’s Land Based Air Defence 1992 93” by Tony Cullen and Christopher F Foss
- Vulcan Mk 149 stinger
- “M163 Vulcan Air Defense System” by the Federation of American Scientists, Military Analysis Network
- M163 Vulcan, WeaponSystems.net
- Air Defense Artillery, 1985
- “While Waiting on the LOS-F-H, Should We Replace PIVADS with the Bradley?” (ADA248511) by Major Jack E. Faires
- “Army Air Defense for Forward Areas: Strategies and Costs (ADA474791)” by the Congressional Budget Office
- “Bradley: A History of the American Fighting and Support Vehicles” by R. P. Hunnicutt
While doing research, I also referenced an operator’s manual for the towed M167A2 from 1987 at the Hathi Trust library. Unfortunately, despite being publicly available, its cover says that it’s export-restricted, so just to be safe I won’t be linking it here.
- Sources for the Mk 149 APDS:
- “400002570-20mm-Mk149-APDS” by General Dynamics
- Sources for the M940 MPT-SD:
- TM-43-0001-27 page 286
- “400000187-20mm-M940-MPT-SD-2023-09-V02” by General Dynamics
- “20mm M940 MPT-SD vs. M246 HEI-TSD Ground to Air Performance Comparison” at the 41st Annual Gun & Missile Systems Conference by D.E. Dillard, P.E. of General Dynamics
- “20mm x 102mm Suite of Ammunition Product Brochure” by Northrop Grumman
- Sources for the AN/VPS-2A: