In-flight Refueling

From rec.aviation.military FAQ by Ross Smith

...The third refuelling system used is the "wingtip-to-wingtip" system, used only by older Russian bombers. In this system, a hose is unreeled from one wingtip of the tanker, and caught by a socket in the opposite wingtip of the receiver; the two aircraft then fly side by side, with the hose joining their wingtips (the length of the hose is comparable to the wingspan of the aircraft). The tankers are all converted bombers themselves, mainly the Myasishchyev M-3MS-2 "Bison-B". This system is very tricky to link up, occasionally dangerous, only usable with bombers (smaller aircraft can't carry the necessary receiving equipment on their wingtips), and gives flow rates even worse than probe-and-drogue; not surprisingly, the Russians have largely replaced it with the probe-and-drogue system, and it will probably become extinct with the retirement of the last M-3 tankers in 1994 or 1995.