The record
The SB.401 is the Mark 4 member of the enclosed APV branch, and its designation follows the same company logic as the SB.301: 'SB' for Shorts Brothers, '4' for the Mark 4 family of Shorlands, '01' for the APV model. It is the personnel-carrying counterpart of the turreted Mark 4 Armoured Patrol Car — same generation, same engine, no turret. Short Brothers of Belfast (the company had reverted to that name in 1977) built it.
The SB.301's six-cylinder engine had been adequate rather than good; Bob Morrison, who has photographed these vehicles since the 1980s, describes it as "still a bit gutless in such a heavy vehicle, especially when fully crewed". The shortfall was answered by Land Rover's Stage One long-wheelbase Series III, introduced in the late 1970s, which carried the 3,532 cc V8 developed for the Range Rover. Shorts reworked the APV around it as the SB.401. Fitting the V8 required the radiator to be moved forward, which the Shorland Site calls the key recognition feature for the model; Morrison points instead to the angular front wheel arches as the easiest identifier of the newer body. The second substantive improvement was ventilation: an extractor fan in an armoured cowl mounted on the roof, which must, as the Shorland Site puts it, have improved crew comfort enormously over the SB.301's reliance on open gun ports. Smoke-discharger arrangements and public-address systems were offered as options, as on any Shorland, and vision blocks could replace the standard pistol ports in the rear.
The Royal Ulster Constabulary is the best-documented user. Five SB.401s came from a cancelled overseas order and were reworked in RUC workshops for internal-security duties; the two sources disagree by a year on when — Bob Morrison dates the purchase to 1985, the Shorland Site says they were supplied in 1986. Morrison photographed one of the five in the yard of Grosvenor Road police station in Belfast in 1988, and the Shorland Site publishes a comparison of two of the five, one as delivered by Shorts and one after RUC modification. At least one ex-RUC SB.401 had reached a Lincolnshire vehicle graveyard by 2011.
Production totals for the SB.401 are not published: the figures Shorts released in 1990 are broken down by turreted mark (Mk 1 100, Mk 2 50, Mk 3 500-plus, Mk 4 250-plus, over 1,000 in all with the Series 5) and do not separate the APVs. The design's afterlife was substantial, however. A coil-sprung development of the SB.401 was redesignated S-55 by Shorts and shown at Farnborough in 1988; Shorts' designer Eric Tuckey demonstrated what was probably an SB.401 prototype on the Kırklareli ranges in Turkish Thrace around 1988, and Otokar of Istanbul subsequently built it under a Land Rover agreement as the ZPT (Zırhlı Personel Taşıyıcı), procured in large numbers by the Turkish government and exported around the Middle East and North Africa. The complete Shorland design passed to British Aerospace Australia in 1996.
