Messerschmitt Me.262, part Twelve, Night Fighter variants

The field conversion kit, turned many Me.262B-1a into night radar-equipped night fighters. They were called Me.262B-1a/U1 and were equipped with on-board FuG 218 Neptun high-VHF radar, using hirschgeweih (stag's antlers) antennae with a set of dipoles shorter than the Lichtenstein SN-2 had used. It was also equipped with the Naxos centimetric-radar-homing gear and was armed with two 30mm Mk.108 and other two 20mm MG 151/20 cannons placed in the nose.
The prototype underwent trials in as late as October 1944 piloted by Hajo Herrman. It was found that the antennae system slowed the aircraft down, but, nonetheless, it was still faster than the British De Havilland Mosquito, the main night bomber of the RAF at the time, and the main adversary of the German night-fighters.
Not many of them were converted, just 26 of them, sixteen by Blohm & Voss in Hamburg from November 1944 until March 1945 and ten of them by the Deutsche Lufthansa, in Berlin-Staaken. All of them were assigned to the 10. Staffel / Nachtjagdgeschwader 11 (10th Squadron / Night-fighter wing 11), near Berlin, which was also equipped with many Me.262A-1a, serving also as night-fighters. Apparently these aircraft accounted for most of the 13 Mosquitoes lost over Berlin during the first three months of 1945. Another unit, named "Kommando Stamp" was initially equipped with Me.262A-1a day fighter, until they obtained some Me.262B-1a/U1s  in April 1945. Their tactics barely changed, as they still used Wilde Sau (Wild Boar) methods, rather than radar-controlled interception. The commander of the "Kommando Stamp" was Kurt Welter who, with 20 claimed kills, was, most probably the most successful Me.262 ace in history.
As the two-seat trainer was largely not available, many pilots had to pilot the Me.262 in any variant without any instruction at all.
There were plans for an improved Me.262B-2a dedicated night-fighter with an enlarged fuselage and increased fuel capacity. Initial plans were fitted with the Neptun radar, but it was expected to fit the Berlin centimetric radar, with improved range and resolutions and the radar's dish hidden in a radome placed in the nose, instead of the clumsy drag-inducing antennae configuration. There were also plans to fit this new, never-built variant, with upward-firing cannons, just like some Bf.110G variants had, called Schräge Musik. But that aircraft will come in another post.

Sources:
1. https://en.wikipedia.org/wiki/Messerschmitt_Me_262
2. http://www.airpages.ru/eng/lw/me262b.shtml
3. https://www.valka.cz/topic/view/15907/
4. Salamander Books - The Complete Book of Fighters