RECENT reports of a day raid upon Eindhoven, Holland, mention for the first time the use of the Lockheed Ventura I. The R.A.F. type is presumably a development of the American machine, originally known as Lockheed Vega 27. This model is powered by two 2,000 h.p. Pratt and Whitney Wasp 18-cylinder radial engines, and has a speed of 275 miles per hour, with a range of 1,500 miles. It carries a crew of four or five, as necessary, and has armament of two movable and two fixed guns in the nose, a Boulton and Paul gun turret on the top of the body, and two movable guns underneath. It is probable that the improved version is superior to this in both performance and armament. The most significant point about the aircraft is that it is a further step towards completing a range of high-performance bombers and fighters that, in total, form a team for heavy day bombing, working upon the theory of smothering the defence when attacking. The Boeing Fortresses operate at great heights, Liberators at a little less, with Venturas, Mustangs and Mosquitoes lower down, even to ground-level. The high speeds and good manœuvrability of these machines make them able to take reasonable evasive action when attacked by anti-aircraft fire, their performance is comparable with British fighters, simplifying the question of their being escorted, and even unescorted their armament and manoeuvrability allow them to put up a good defence against enemy attacking fighters.