The de Havilland Venom NF.3

The Venom was a two-seat "all-weather" or night fighter which in 1956 was the backbone of Britain's air defences. All night and every night, aircrews on QRA (Quick Reaction Alert) duty sat in their cockpits waiting, ready to fire the starter cartridges and be in the air within two minutes of the flash of the telebriefing lamp on the cockpit control panel.

There were in fact 1- and 2-seat versions of the Venom. The single-seat Venom FB.1 was a development of the De Havilland Vampire with the more powerful Ghost jet engine replacing the earlier Goblin; initially produced as the Vampire FB.8 it went into service for the first time in September 1949. Other single-seat fighter-bomber versions were produced through the 'fifties, and a modification of the FB.50, built under license, was still used by the Swiss Air Force as a single-seat interceptor well into the 'sixties. However a radar-equipped two-seat night-fighter series, beginning with the Venom NF.2, was ordered into production by the RAF in late 1950.

De Havilland's private-venture prototype of the NF.2 had been praised (A & AEE Report 868/2) for its excellent agility, its cockpit design and the good all-round view afforded by the framed bubble canopy. The radar operator sat to the right and slightly to the rear of the pilot with the radar equipment in front of him. The arrangement was considered relatively spacious, though in reality cramped, and good for vital team-spirit with its side-by-side seating. Initially the rate of roll was found to be poor and the aircraft a little unstable in certain flight attitudes. But these problems were designed out and after further lengthy trials at Boscombe Down the Venom NF.2 entered service in May 1953.

However when the first Venoms were delivered to 23 Squadron Coltishall in November 1953 further teething problems were encountered with turbulence and a worrying structural weakness in the wings near the junctions of the twin tail booms. There were a number of crashes during 1954 which led to the entire squadron being temporarily grounded, giving the new Venom a suspect reputation. But whilst 23 Squadron continued to operate the plane under height restrictions, not becoming fully operational with the Venom NF.2 until that summer, work went on to correct the problems leading to a new version with minor airframe and canopy modifications designated the NF.2a. And on April 18 1955 No. 253 Squadron, No 11 Group, Fighter Command, was reformed at RAF Waterbeach, near Cambridge, becoming the first operational QRA squadron to be fully equipped with the new Venom NF.2a.

The NF.2a was given a clear-view "clamshell" canopy affording even better pilot visibility, with a hydraulic jettison device for safer evacuation at high speeds, and was further improved by redesigned fins and a tailplane faring to reduce control-surface buffeting which had been a problem at high Mach numbers. The NF.2a was in many ways a superb and versatile aircraft, with a better rate of climb than the Gloster Meteor NF.11 and excellent high-altitude performance.

The core of each squadron was built from highly experienced nightfighter pilots from existing squadrons - a Squadron CO of the rank of Wing Commander plus two Flight Commanders already of the rank of Squadron Leader - which pointed up the significant role of these units in Fighter Command's growing all-weather air defence force. Considerable training was given before their crews acquired operational status, and Squadron operational training was ongoing, with frequent Bomex (simulated bomber attack exercise) drills, aerial gunnery practice, and practice interceptions (P.I.s) in which two Venoms would alternate as targets for each other under GCI control. Squadron establishment was 16 Venoms (plus some spares), a couple of Vampire T.11s for training and instrument check-out purposes, and one or two Meteor F.8s as hacks and for towing gunnery targets. The 16 Venoms made up two Flights of 8, one of which operated at night, the other by day, rotating weekly.

The NF.3 version came into service close on the heels of the NF.2a, the first few being delivered for trials in autumn 1954. The intended suite of improvements was trimmed back owing to the 1952 decision to adopt the Gloster Javelin as the standard RAF all-weather fighter by 1955, but it had an uprated Ghost 104 power plant, minor airframe modifications, much improved APS-57 AI radar mounted in its characteristic grey perspex nasal radome, and radar-ranged gunnery, all of which made it a noteably superior aeroplane.

A rare photograph of Venom #WZ315 F/23 Squadron RAF, flown by F.O. Les Arthur with navigator/radar operator F.O. Grahame Scofield on August 13 1956
(Eric Taylor, from R. Lindsay, De Havilland Venom)

Aside from its performance, enabling it to accomplish successful Bomex interceptions on Canberras operating at more than 40,000' and at speeds of over 550 mph, one reason for the Venom's popularity with aircrews was the side-by-side cockpit arrangement. Unlike in the Meteor night-fighter, an intercom failure in a Venom did not necessarily mean the end of a sortie, as the radar operator could shout instructions to the pilot. Another advantage over the Meteor was that the Venom's four Hispano cannon, each delivering 150 rounds of 20mm shells, were nose-mounted in a belly-pack close to the aircraft centre-line, which meant that a stoppage in a single barrel would not cause the aircraft to yaw. (A stoppage in one of a Meteor's wing-mounted cannon would at once cause the aircraft to swing off the target.) The Venom also carried a gun camera loaded with cine film mounted on brackets on top of the GGS.5 radar gunsight, which could be triggered either manually or automatically by the firing mechanism.

The first operational NF.3 squadron was 141 Squadron at RAF Coltishall, and the second, 23 Squadron at the same base, was equipped with the new planes a month later in July 1955.

The NF.3 reigned for about 18 months before the Coltishall squadrons began to be re-equipped with the new Javelins in February/March 1957, followed by other squadrons. Part of the reason for the relatively brief service life of the jet was conservative RAF air-safety policy. A standing presumption in favour of twin-engined aircraft dictated that Venoms were replaced with Javelins even before the older Meteors, despite the fact that the mature Venom had an excellent safety record. By September 1957, 89 Squadron Stradishall remained the sole Venom squadron, and by the end of the year they too were equipped with the more advanced Gloster Javelin.